Preface - ZTE...Executive Vice President of ZTE: Tian Wenguo January 1st, 2009 Preface Moving Steadily Through the Storm T he global financial storm caused by the U.S. subprime loan

Executive Vice President of ZTE: Tian Wenguo

January 1st, 2009

Preface

Moving Steadily Through the Storm

The global financial storm caused by the U.S. subprime loan debacle is leading to a global economic crisis. The telecom industry, which has been in steady growth since the dot-com bubble

burst in 2000, is more and more affected by the tempest. To cope with the turmoil, the first thing we need to do is

to identify the possible impacts resulted from the crisis, and then take active countermeasures to optimize the industry structure, products, and management.

Despite the heavy blow, the value chain of the telecom industry remains intact. ZTE, a leading global provider of telecommunications equipment and network solutions, has the confidence to weather the storm together with global telecom operators.

Many governments have launched various policies to protect the economy. The Chinese government has announced a 4-trillion-yuan stimulus plan, and the Ministry of Industry and Information Technology is going to initiate a policy package to revive crisis-stricken industries. Any advance in the telecom industry, a basic and pillar industry in China, will significantly stimulate the country’s overall economic growth. While the more developed European telecom market poses an anchor in the storm, the emerging markets are rising up as an engine, leading the global telecom industry through the wind.

Backed by strong government support, ZTE is determined to seek further development through relying on its technical innovations and enhancing its core competitiveness. In short, we are committed to providing custom-made products and services to telecom operators throughout the world.

Corporate culture is the cornerstone in the sustainable development of any business. ZTE TECHNOLOGIES works as a window of ZTE’s corporate culture as well as a bridge linking ZTE with its customers. I sincerely hope that in the coming year the magazine can reflect our new approaches and attitudes, focus more on customer demands and services, and provide more needed information to readers, hence contributing our bit to the telecom industry in battling the storm.

Vol. 11 No. 1 Issue 108 January/2009

A Monthly Publication

Interview

ZTE USA Strengthens Momentum in the U.S. Telecom Market―An interview with Anthony E Ortolani, President and CEO of Smart PCS

P8

Flexible Applications Enabled by ZTE’s OneNetwork SolutionZTE’s OneNetwork solution can meet different requirements of scenarios such as 3G/LTE, 2G/3G/LTE, and WiMAX/LTE

Research Note

P10

Rapid and Economical Deployment of Quality WiMAX Networks In the fiercely competed fixed and mobile markets, WiMAX has been more and more valued and adopted by carriers

P13

Cover Story

From a Follower to a Market Leader —An interview with Mr. Zhu Jinyun, General Manager of ZTE’s UMTS products

P5

www.zte.com.cn

The Development of SDR TechnologySDR provides a universal radio communication platform, based on which, new services can be delivered and new technology can be used through software update

P15

ZTE Unveils World’s First Next Generation PON Equipment

ZTE Wins CMPak US$100 Million Capacity Expansion Project

ZTE Secures 55% of China Unicom GSM VAS Deal

ZTE Shows Strong Confidence in Building 3G Networks for China’s Mobile Operators

Corporate News

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ZTE TECHNOLOGIESJanuary 20092

Editorial Board

Editor-in-Chief: Gu Yongcheng

Deputy Editor-in-Chief: Huang Xinming

Editorial Director: Zhao Lili

Executive Editor: Yue Lihua, Liu Yang

Editor: Olga Saprykina

Circulation Manager: Wang Pingping

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ZTE Profile

ZTE is a leading global provider of

telecommunications equipment and network

solutions. ZTE's product range is the most

complete in the world—covering virtually

every sector of the wireline, wireless, service

and terminals markets. The company delivers

innovative, custom-made products and

services to customers in more than 135

countries, helping them achieve continued

revenue growth, while shaping the future of

the world’s communications.

Solution

ZTE’s HSPA+ SolutionHSPA+ enables operators to achieve performance comparable to LTE at a relatively small upgrade cost, fully protecting operators’ investment

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28ZTE Assists Hong Kong CSL to Achieve ExcellenceCSL was in urgent need of reconstructing its four networks into a single network with good quality and continued evolution

26Moving Towards Convergence For operators who need to operate both CDMA and GSM/UMTS networks, ZTE’s convergent core network solution is an optimization scheme that can bring significant CAPEX and OPEX savings

Making a More Competitive CDMA2000Low peak data rate and poor service experience for edge users are major problems with EV-DO Rev.A

24

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Case Study

Third Eye

Overview of SDR MarketZTE is one of the first vendors to launch a SDR base station that can be upgraded to LTE though a baseband add-on and software upgrade

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ZTE TECHNOLOGIES January 2009 3

ZTE Unveils World’s First Next Generation PON Equipment

Corporate News

ZTE Wins CMPak US$100 Million Capacity Expansion Project

ZTE has rolled out the world’s first Next Generation PON equipment―the ZXA10 C300

multi-service access platform. The ZXA10 C300 was launched at EXPO COMM ITALIA 2008 where ZTE also

showed the rest of its range of Green Broadband solutions as well as the ZXMSG 6000 multi-service access gateway, the micro DSLAM ZXDSL9812 and the company’s Broadband Easyservice system.

The ZXA10 C300 i s a green , converged, future-proof, high-capacity, multi-service access platform. It is the world’s first unified platform supporting GPON, EPON and P2P as well as the emerging next generation IEEE 10G EPON and FSAN/ITU-T NG PON in a

single shelf. The ZXA10 C300 features high capacity, long reach and high integration, meeting the requirements of the largest central offices. It has been designed to support migration from existing 1G EPON and GPON systems towards IEEE 10G EPON and FSAN/ITU-T NG PON whenever operators are ready to migrate. The system supports a wide variety of legacy and next generation ONUs/ONTs, so it is ready for service in a wide range of FTTx scenarios.

(ZTE Corporation)

ZTE added another significant customer win to its growing list of service providers deploying

its GSM solution. The company recently announced the signing of a US$100 million contract with China Mobile’s Pakistan subsidiary (CMPak) to help them expand the capacity of their GSM infrastructure as part of its Phase 2 project.

The project covers central Pakistan,

where the highest GDP in the country is produced and more than half of the country’s population resides, hence becoming the main source of most operators’ voice data service profits. The central Pakistan territory comprises of eight cities and regions, including Multan, Faisalabad and Lahore, Pakistan’s second largest city.

Under the GSM infrastructure extension

project, ZTE will provide CMPak with its latest 8000 series of base stations using a unified total IP hardware platform. The solution allows operators to smoothly evolve their telecom infrastructure into total IP integrated mobile broadband networks, helping them reduce network evolution cost, lower their TCO, and continuously enhance their profitability.

(ZTE Corporation)

ZTE has clinched a 55% share in China Unicom’s 2008 bulk purchase of GSM Value-Added

Service (VAS) systems, according to the recently announced tender result. The China Unicom tender involves the provision of key service platforms of GSM network that will allow the operator to offer quality mobile services nationwide. By securing over half of

the tender bids, ZTE further proves its expertise and leading market position in the VAS technology arena.

As part of the contract, ZTE is providing the biggest number of nodes for China Unicom’s three major p roduc t o ffe r ings , Co lor Ring Back Tone (CRBT) platform, Multimedia Message Service (MMS) management p la t form and WAP

services management gateway, which contribute to the bulk of the operators’ VAS revenues. ZTE won 17, 14 and 12 nodes for the above three products respectively, in addition to providing telecom solutions to other key product areas and services such as authentication center, interconnection gateway and enterprise applications.

(ZTE Corporation)

ZXA10 C300

ZTE Secures 55% of China Unicom GSM VAS Deal


ZTE Shows Strong Confidence in Building 3G Networks for China’s Mobile Operators

Corporate News

China Mobile, was awarded a license for TD-SCDMA, the domestically-developed 3G standard. The other two main carriers, China Telecom and China Unicom, received licenses for the U.S.-developed CDMA2000 and Europe’s WCDMA, respectively.

“With the company’s comprehensive strengths in the 3G industry chain, from 3G network equipment to cell phones, ZTE wil l be devoted to backing China’s 3G service providers in the planning and construction of new telecom networks,” the statement said.

Echoing the Chinese Government’s expectation to boost mainland economy through new network constructions, ZTE aims to continue investing in the R&D of 3G technologies and recruit more employees, thus retaining its preferential position in competing with peer equipment and cell phone manufacturers.

ZTE expressed strong confidence in playing a big role in the follow-up for network constructions.

“With 10 years ’ e ffor t s , ZTE has achieved rich accumulations in the development and applications of al l mainstream 3G standards, including WCDMA, TD-SCDMA and CDMA2000. ZTE now is one of

the global mainstream suppliers of equipment for 3.5G HSPA/HSPA+/EV-DO, and leads the industry in SDR-based multi-mode platform and IP technologies. The company also keeps pace with the industry development in TDD LTE and FDD LTE. We are confident about the coming upsurge of 3G implementation,” said the company statement.

ZTE has ranked No.1 in global CDMA sales for two consecutive years, and its share in the recent procurement of China Telecom’s Phase 1 CDMA2000 network construction increased remarkably from the previous 32%. As for TD-SCDMA, ZTE maintains its role as the largest TD-SCDMA supplier with advantages in technology and commercial use. As for WCDMA, ZTE deployed its equipment in over 30 countries. Particularly, its HSPA/HSPA+ systems have seen rapid growth of commercial use; its new generation RRU+BBU base stations and SDR products have been highly recognized by operators in Europe, Hong Kong, South America and Asia Pacific. The new generation technologies enable ZTE and operators to work together for new opportunities with operable, profitable and evolvable 3G networks.

ZTE, a leading global provider of telecommunications equipment and network solutions, voiced

its strong support for the issue of third-generation (3G) mobile licenses in the Chinese mainland on January 7, 2009.

According to ZTE’s company statement, it is determined to provide customized 3G solutions to mobile service providers, hence playing a major role in the new service market.

The Minis t ry of Industry and Information Technology (MIIT), China’s telecommunications supervisor, issued long-awaited 3G licenses to three mobile operators on January 7, a move that is expected to lead to billions of dollars being invested in building new networks.

China’s biggest mobile operator,

January 7, 2009 (Source: www.c114.net)


e are confident that we can satisfy operators’ requirements. We are always ready to meet

Cover Story

—An interview with Mr. Zhu Jinyun, General Manager of ZTE’s UMTS products

From a Follower to a Market Leader

Zhu Jinyun joined ZTE in 1998 and now acts as General Manger of ZTE’s UMTS products. He served as Head of BSS Hardware Development Dept. in ZTE’s CDMA R&D Institute from 2000 to 2002, and General Manager of ZTE’s CDMA products from 2002 to 2007. As General Manager of ZTE’s CDMA products, he led the product line to make outstanding achievements one after another and drive market share growth year by year. During 10 years in the telecom industry, he has accumulated much technical knowledge and rich management experience.

market challenges and edge out other vendors in severe competition,” said Zhu Jinyun, General Manager of ZTE’s UMTS products, in a recent interview. Despite his mild tone, Zhu was very determined about ZTE’s success in the 3G market in China.

According to Zhu, ZTE set a strategic objective for UMTS products earlier this year, which is to be among the world’s top three in three years and the world’s No.1 in five years. “Guided by this goal, ZTE will invest heavily in the development of UMTS and Long Time Evolution (LTE) products,” said Zhu. Based on the accumulation of wireless technologies like GSM, TD-SCDMA, CDMA and WiMAX and an outstanding R&D team, ZTE will excel in the LTE field.

UMTS in 10 Years: From a Follower to a Leader

Journalist: ZTE has been involved in the research and development of UMTS products for 10 years since 1998. Could you give us a brief review of the development of UMTS products in the past 10 years?

Zhu Jinyun: The past 10 years wi tnessed the g rowth o f ZTE’s UMTS products from a follower to an industry leader. ZTE’s high management has been attaching great importance to the development of UMTS technologies and has been investing huge resources. Since we


property rights, which improved the power amplification efficiency to an industry-leading 33%. Technical breakthroughs in baseband and power amplification technologies in the two years significantly improved ZTE’s product strength.

In 2007, we continued our R&D in HSPA and passed the 5.76Mbps High Speed Uplink Packet Access (HSUPA) test. ZTE was also the first company that completed the Interoperability Testing (IOT) of Multimedia Broadcast/Multimedia Service (MBMS).

This year, we launched the Software Defined Radio (SDR) technology, which solved the problems concerning the coexistence of multiple frequency bands and modes and enabled smooth

network evolution.The improvement o f p roduc t

competitiveness led to many market breakthroughs. In 2007, ZTE entered the European market and cooperated with operators in Estonia, France, and Romania. In 2008, we deployed large-scale networks in Romania, Hong Kong, and Brazil.

Over the past 10 years, ZTE’s UMTS product line has been dedicated to providing advanced products and technologies. We have caught up with industry-leading vendors and surpassed them. In evaluating the technologies of new products, operators recognized that ZTE’s technologies not only had reached the same technica l level as traditional giant vendors, but had surpassed them in product customization and follow-up roadmap.

J: Could you please introduce the achievements made by ZTE’s UMTS product line in technical innovations?

Zhu: ZTE’s technical innovations in UMTS can be found in three t e c h n o l o g i e s . T h e f i r s t i s t h e BBU+RRU solution that leverages fiber-optic remote technology. This solution can effectively save resources and improve coverage, and has been widely used in building CDMA and TD-SCDMA networks.

The second is the SDR base station platform. In the early phase of network construction, a common concern will be smooth evolution to HSPA, HSPA+ and LTE. As the 2G network and the 3G network will coexist in the long term, operators are also concerned about the convergence and coexistence between 3G and 2G networks. The SDR base station platform offers effective solutions for such problems.

The third is the home NodeB, which will be put into commercial application

started UMTS development in 1998 till 2002, we were a follower after other vendors in the industry. In 2004, we launched the V3 series of products and a unified platform. Moreover, we originated the distributed “Operation and Maintenance Factory” networking concept, which helped us narrowing the gap with industry-leading vendors.

In 2005, ZTE launched its self-developed chips. This showed that we had caught up with, even surpassed industry-leading suppliers. In the same year, ZTE became the first supplier that enabled High Speed Downlink Packet Access (HSDPA) at 10.8Mbps.

I n 2 0 0 6 , Z T E l a u n c h e d t h e DPD+Doherty power amplification technology with its own intellectual

Cover Story

ZTE TECHNOLOGIES January 2009 �

in the second half of this year. Home NodeB effectively solves indoor coverage problem, hence supporting the provision of all services.

J: Just now, you have mentioned that ZTE was quite strong in product customization. Could you introduce some cases?

Zhu: Many cases can show our strength in product customization. Here I’ll give some typical examples. In implementing the project of Brazil Telecom, the largest operator in Brazil, we completed deploying 100 base stations in one month and finished Phase I network construction in three and a half months. The operator started network operations ahead of the schedule. In this case, the use of the BBU+RRU distributed base station enabled flexible, fast network deployment.

When cooperating with Romania Zapp, we provided the operator with the customized UMTS/CDMA convergent solution, which made UMTS and CDMA systems share the same site. With this solution, the operator can access the HSPA service while protecting existing CDMA investments. This case illustrates the flexibility and customization strength of our solutions.

In a project implemented in Hong Kong, our solution focused on future evolution and low Total Cost of Ownership (TCO). Our products feature low power consumption and small area occupation. We replaced the operators’ three big cabinets with one small frame, which saves a lot of expenses. The high-end, advanced market always has high Operation Expenditures (OPEX). Our solution can help customers decrease the OPEX and offer future evolution path. ZTE is

able to provide customized solutions to meet different operator requirements, in orientation to the characteristics of different markets.

Meeting the Development Opportunity in China’s 3G Market

J: The kickoff of the 3G market in China wi l l de f in i te ly a rouse compet i t ions among equ ipment vendors. How will ZTE meet this opportunity and challenge?

Zhu: The battle for the commanding heights is absolutely cruel. This can be seen from the mergers and regrouping of many international vendors. ZTE has been growing up in such an environment. Fortunately, we survive the competition and will continue growing. We are very confident.

Our confidence is supported by three facts. First of all, after 10 years of R&D, we are ready in terms of technologies and products. Now ZTE has industry-leading technologies, and we can quickly respond to customer needs and offer customized solutions.

The second fact is ZTE has proposed the distributed solution. This solution combined with the integrated indoor distribution system will help build a quality network for China Unicom.

The third fact is we have a deep understanding about China Unicom’s market needs, as ZTE’s core network and service network equipment had high occupancy in China Unicom’s 2G network.

These are our advantages. With such advantages, we are confident that we can satisfy operators’ requirements. We are always ready to meet the market challenges and win the competitions.

Taking over the Commanding Heights of LTE

J: So far, mainstream operators in

the world have selected LTE as the next evolution of mobile technologies. What has ZTE done in the LTE field? What plan does ZTE have for the future?

Zhu: ZTE began investing in the R&D of LTE in 2006. The company’s high management has attached great importance to LTE and has injected investments in the R&D. Our investments include not only manpower in the development of system equipment, but also a lot of funds in the development of the baseband technology and the chips. A lot of money was also invested in UMTS in order to continuously optimize and improve chip capabilities.

The baseband technology is the core of wireless technologies. Only by mastering the core technology can we meet the operators’ customized requirements l ike low TCO and environment protection, can we get an advantageous position in the industry’s value chain.

The development of both LTE and UMTS is based on the mature application of 2G technologies. ZTE’s R&D of LTE benefits from a rich accumulation of wireless technologies including GSM, TD-SCDMA, CDMA and WiMAX and is backed by an experienced R&D team. We started following competitors in GSM and WCDMA fields. In the LTE field, however, we surpassed our competitors from the very beginning, thanks to the previous technical accumulation.

In early 2008, ZTE set a strategic objective for UMTS products: to be among the world’s top three in three years and the world’s No.1 in five years. Guided by this goal, ZTE will invest heavily in the development of UMTS and LTE products. Such a grand objective will stimulate us in making continuous efforts.


Interview

ZTE USA Strengthens Momentum in the U.S. Telecom Market—An interview with Anthony E Ortolani, President and CEO of Smart PCS

In December 2008, Smart PCS, an unlimited no contract pre-paid carrier, selected ZTE USA, a subsidiary of ZTE Corporation,

as the key CDMA infrastructure and device vendor partner to support its initial service launch. ZTE USA’s mobile Softswitch equipment and All-IP CDMA2000 1xEV-DO base stations are being used to construct the networks in the initial markets the carrier will serve, which include northwest Georgia and Tennessee, as well as future markets to which the carrier will expand. Smart PCS also chose ZTE USA’s data cards and high quality, feature-rich handsets to offer to its new subscribers.

What are the major considerations that Smart PCS used in choosing ZTE as its network equipment partner?

How will Smart PCS develop its future network? With these questions in mind, the journalist of ZTE TECHNOLOGIES made an exclusive interview with Anthony E Ortolani, President and CEO of Smart PCS.

Journalist: It’s our great honor that you gave us the opportunity to interview you. ZTE TECHNOLOGIES is ZTE’s own magazine; our major readers include our 50,000 employees and telecom industry partners in 135 countries around the world. First of all, would you please give us a brief introduction of Smart PCS and your major business?

Ortolani: Smart PCS is a regional cellular carrier offering unlimited local, long distance and international wireless services including voice, text

and picture messaging, and Internet browsing.

J: As a fast growing and new

regional CDMA network provider, what are your strategies to compete with other operators?

Ortolani: Our strategy is simple. We offer customers the best wireless experience, which includes coverage, service and customer care. In addition, Smar t PCS is the only wire less provider within our network that offers an unlimited “all you can eat” program, and no contract is required.

J: What is your current network

coverage status? Could you please d e s c r i b e y o u r f u t u r e n e t w o r k development plan?

Ortolani: Our current network


Anthony E Ortolani currently serves as President and CEO of Smart PCS, a no contract, unlimited wireless telephone company based in Dalton, GA. Formerly he worked as President and CEO of Central States Tower (CST), a Chicago based Tower Holding Company, a national consolidator of wireless infrastructure. Prior to CST, Mr. Ortolani was Founder and Managing Operator of Communication Enhancement, which was one of the nation’s largest wireless infrastructure and network development companies, owning and operating over 200 towers.

coverage includes Northern Georgia and Southern Tennessee. However, strategic roaming agreements are in place, which allows our customers to use their wireless devices anywhere throughout the United States and parts of Mexico. Ongoing negotiations are underway to acquire additional frequency spectrum to further enhance Smart PCS’ network.

J: Regarding handset terminal, ZTE is No.1 handset manufacturer in China, and ranks top 6 worldwide; we just shipped our 100 mill ion handsets in September. What is your strategy in choosing your handset partners? What do you think about ZTE handset?

Ortolani: In choosing a handset provider, Smart PCS is aligned with

vendors who meet or exceed our expectations in terms of cutting-edge technology, quality products and delivery timetables. ZTE continues to satisfy these requirements.

J: As far as I know, Smart PCS

has partnered with ZTE to construct the network, what are your major considerations in choosing ZTE as your network equipment partner?

O r t o l a n i : A s a n e w c a r r i e r launching its service for the first time, we needed a vendor partner that would offer us mature, state-of-the-art equipment and devices, but at an affordable price point. Again, Smart PCS selected ZTE because of the state-of-the-art technology and equipment that has been provided at very competitive prices. In addition,

ZTE has stood behind its product by maintaining a full staff on site to ensure that our launch went smoothly.

J: As a leading Chinese telecom equipment vendor, ZTE has started to spread its wings in the United States since 2002. Would you please give us some suggestions about how we should develop the U.S. telecom market and how we can serve for U.S. carriers like you better?

Ortolani: Continue to provide the quality product and customer care that you now deploy and penetration into the United States will continue to grow. Our experience with ZTE has been very positive and we look forward to working with ZTE on all of Smart PCS’ future deployments.


Research Note

Li Liangbo

Flexible Applications Enabled by ZTE’s OneNetwork Solution

ZTE’s OneNetwork Solution ConceptWith many years of experiences in

wireless technologies, ZTE launches OneNetwork solution including unified RAN based on SDR technology, unified all-IP core network and unified OMC platform.

Z T E ’s u n i f i e d S D R s o l u t i o n can support multiple radio access technologies, for example, GSM, CDMA, WCDMA, TD-SCDMA, WiMAX and LTE. With SDR solution, one set of equipment can be software configured as dual-mode or multi-mode.

The BTS equipment generally consists of two parts: Baseband Unit (BBU) and RF Unit (RU). The BBU is based on the MicroTCA architecture and adopts SDR technology to support different technologies. The frequency of RU can be flexibly adjusted within 20MHz through software configuration in 900/1800/2100/2600MHz frequency bands.

The unified all-IP core network based on the ATCA archi tecture separates transmission from services and enables large-capacity transmission for mobile networks.

The Unified Element Management Platform (UEP) developed by ZTE serves as the operation and maintenance system, network element management system, network management system,


and service management system.Z T E ’s O n e N e t w o r k s o l u t i o n

can meet different requirements of scenarios such as 3G/LTE, 2G/3G/LTE, and WiMAX/LTE.

Evolution from 3G to LTE Some operators plan to launch 3G

as soon as they get 3G licenses. But they are not clear about how to evolve to LTE in the future. The traditional 3G solution only supports single-mode RAN and the core network. If operators want to upgrade from HSPA to LTE, they have to alter most of the hardware and even build a new network. This means investing more CAPEX in the network deployments and more OPEX in the network operation.

To transform the traditional network evolution concept, ZTE launches its OneNetwork solution, which can help implement a single RAN network and core network, paving the way for LTE.

ZTE’s OneNetwork solution can meet requirements of UMTS network deployments in 900/1800/2100MHz bands. After a UMTS network is built, some remaining frequency bands can be reused in the LTE deployment, or parts of UMTS frequency bands are refarmed to LTE. Below are some examples of such application scenarios.

Suppos ing ope ra to r s own ing

16MHz in 900MHz band want to firstly launch UMTS900 and refarm most of GSM900 frequency bands to UMTS900 usage. They can use ZTE’s OneNetwork solution (as shown in Figure 1) to realize the evolution: The first step is to launch UMTS900 S111 with HSPA support and attract some of the GSM subscribers. The second step is to upgrade UMTS900 network from S111 to S222 with HSPA+ support. In the future the network can evolve to LTE, requiring no massive hardware change. In order to reduce the initial investment, ZTE suggests deploying one RU per sector in the beginning. In the near future when LTE is ready for rollout, another RU will be added to support 2×2MIMO or 4×4MIMO.

evolution of the core network. All the elements in the core network are based on the ATCA platform. With a software upgrade, functions of one type of network element can be converted to those of another type of network element. The SGSN, for example, can be converted to the MME server by a software upgrade. The GGSN can be software configured to an SAE gateway.

If the operators only have 8MHz in 900MHz band, ZTE’s OneNetwork so lu t ion can be used to l aunch UMTS900 S111 network at first. After all the subscribers switch from 2G to 3G, the remaining spectrums can be refarmed to LTE usage. Therefore, in the near future, UMTS900 S111 and LTE 1.4M S111 or S222 will coexist.

If the operators have 15MHz in 2100MHz or 1800MHz bands, they can use ZTE’s OneNetwork solution to deploy UMTS S111, S222 or S333 networks initially. In the future, the operators can introduce LTE with only a software upgrade and a little hardware change.

Coexistence of 2G/3G/LTE The operators with outdated GSM

equipment face the h igh OPEX problem. They want to swap 2G equipment with evolvable equipment,

Figure 1 OneNetwork solution ensures that UMTS will evolve to LTE

UMTS900M S111 UMTS900M S222

UMTS

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2009 (UMTS)2009 (UMTS) 2010 (UMTS)2010 (UMTS) Future (U+L)Future (U+L)

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WiMAX TDD 2.5G(2570–2620MHz)

Choice BChoice BRe-farmingRe-farming LTE TDD

2.5GHz

WiMAX TDD 2.5GHz

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Choice CChoice CRe-farmingRe-farming

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Choice AChoice AWiMAX 16eWiMAX 16m

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2.5GHz

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LTE FDD2.6GHz

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WiMAX 16m2.5GHz

ZTE’s OneNetwork solution can also help operators achieve the smooth

12 ZTE TECHNOLOGIESJanuary 2009

that is, equipment that supports EDGE, HSPA and even future LTE. In this scenario, the SDR or multi-mode solution is the key to success. ZTE’s OneNetwork solution supports GSM/EDGE, UMTS/HSPA/HSPA+ and LTE. All the transformations from 2G to 3G and LTE are defined by software and need little hardware change.

Supposing operators owning 16MHz in 900MHz band will get 20MHz in 2600MHz band in the future. With an old GSM network, they have to swap GSM equipment with new kinds of SDR or multi-mode equipment. ZTE OneNetwork solution can meet the operators’ requirements and help them realize a step-by-step upgrade process. The first step is to launch GSM/EDGE network to replace the existing 2G network. After that, the operators can launch UMTS900 network with HSPA and HSPA+ support. In the future, when they gets 2600MHz spectrum, LT E n e t w o r k c a n b e l a u n c h e d requiring no massive hardware change. The evolution process is shown in Figure 2.

In the future when operators get 2600MHz spectrum, LTE can be launched in a new frequency band. Finally, three kinds of networks, GSM S222, UMTS S222 and LTE S111, will coexist for a long time. The radio access network will consist of one type of base station, and the core network will be unified.

Flexible Choices Between LTE and WiMAX

In some count r ies , 2500MHz spectrum licenses in the 2500 to 2690MHz range will be released for the mobile market. For the fixed operators who want to take part in the frequency auction and compete with other mobile operators, they will launch OFDM networks as soon as they get frequency licenses. Since the WiMAX ecosystem is more mature, the fixed operators will enter the mobile market by deploying WiMAX TDD.

If operators get TDD frequency band in the 2570 to 2620MHz range, they can deploy WiMAX TDD at first. Then, WiMAX 16m will be introduced when the ecosystem is mature and WiMAX 16e and 16m will coexist for some years. Finally, the network will evolve to WiMAX 16m. This evolution route is shown as Choice A in Figure 3.

Figure 3 Flexible evolution choices for WiMAX operators


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to evolve to LTE TDD (Choice B). WiMAX TDD will be refarmed to LTE TDD usage in the middle stage of the evolution. With ZTE’s OneNetwork solut ion, th is evolut ion needs a software upgrade and addition of some hardware.

When the opera to rs ge t FDD frequency band within the 2500 to 2570MHz range for the uplink and within the 2620 to 2690MHz range for the downlink, they can deploy WiMAX at first if the relevant auction sets no limits on the usage of TDD and FDD technology. After that, if operators want to transform from WiMAX to LTE, the WiMAX frequency bands can be refarmed for LTE FDD. With ZTE’s OneNetwork solution, the baseband unit and core network will be reused; the radio frequency units have to change to support FDD. This evolution rout is Choice C.

ZTE’s OneNetwork solution is also helpful to those operators who have already deployed WiMAX networks. When the network equipment can not smoothly evolve to WiMAX 16m, or operators want to convert to LTE, they can choose ZTE’s OneNetwork solution to enable a swap of the existing WiMAX network.

All in all, this solution can meet operators’ different requirements of conversion between WiMAX and LTE.

ConclusionZTE’s OneNetwork solution is

future proof as it can help operators achieve smooth evolut ion while reducing TCO. It is flexible enough to be applied in different scenarios. Up till now, ZTE’s OneNetwork solution has been successfully applied by China Telecom, China Mobile, Telstra, Brasil Telecom, and other operators.

Figure 2 Long-term coexistence of 2G/3G/LTE


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WiMAX 16m2.5GHzIn the first step, the GSM S444

network will be launched. Each sector has 20W transmit power on the top of cabinet. In the second step, the UMTS900 network will be launched, some of the 2G subscribers will switch to 3G, therefore the GSM capacity will decrease from S444 to S222.

In this evolution, the hardware has the highest utilization.

If the WiMAX 16m ecosystem comes of age at a much later time than LTE TDD, operators can choose

Research Note

13ZTE TECHNOLOGIES January 2009

Zhang Shizhuang

In the fiercely competed fixed and mobile markets, WiMAX has been more and more valued and adopted by carriers, because it not

only uses next generation core wireless technologies, OFDMA and MIMO, but also features a complete end-to-end industrial chain and promising market opportunities. Mohammad Shakouri, WiMAX Forum Board Member and Vice President of Marketing, noted that the number of WiMAX deployments had reached 305 in 118 countries/regions worldwide by July 2008. According to the empirical data from WCDMA 3G network construction, most of subscriber activities take place indoors, and problems related to indoor coverage of WCDMA have gradually been exposed and given rising concerns. WiMAX is now in a harsher situation, facing both competition from existing 3G technologies and challenges from next-generation LTE technology. Therefore, WiMAX network construction has to solve the problem of improving indoor coverage at the very beginning.

WiMAX Implementation Issues Faced by Carriers

WiMAX has to deal with a wide range of coverage scenarios such as outdoor macro BSs, office building, hotspots, underground, boundary of residential areas, mobile vehicles, etc. In most of these scenarios, the network quality is

improved by enhancing indoor coverage.Many types of carriers may implement

WiMAX networks: emerging carriers, fixed network carriers, cable carriers and traditional 2G/3G mobile carriers. The problems they are facing include:■ Minimizing the number of BSs for

indoor coverage: All carriers also have to improve the coverage quality of outdoor macrocell networks as much as possible.

■ Since WiMAX deployments usually use TDD, to reduce interference between BSs and terminals, it is imperative to ensure synchronization among systems. Currently, the most common approach is to equip each indoor BS with a GPS antenna system, which results in huge installation and construction work, and increases O&M costs.

■ In the early phases of network deployment, the primary goal is to improve coverage of WiMAX s ignals ; in some commercia l facilities, as users develop the habit of logging onto the Internet in the later phases, high requirements are put on the indoor coverage and capacity. It is impossible for traditional indoor distribution systems to solve such problems.

■ Diversified transmission resources available for indoor implementation: A fixed network carrier generally has Ethernet or fiber optical cables in a

building; a cable carrier generally has only cable resources in a building; it is hard for an emerging carrier to obtain wired resources for the last mile, particularly in a building; resources of traditional 2G/3G mobile carrier vary largely, some of them have partially available transmission resources, e.g. FE, E1/T1, at some BSs, and some has no sufficient resources for WiMAX data bearing.

■ Network planning should solve interference and network optimization problems. Requirements on network planning and optimization would lead to increased O&M costs.

Outdoor Networks with Good Coverage

Empirical data from mobile network construction indicate that the equipment cost at the wireless access side account for about 30% of the total network building cost; and the largest portion of investment goes to the supplementary transmission facilities, towers, power supply and engineering. Therefore, how to minimize the number of BSs is the focus of WiMAX network building. There are a number of ways to improve outdoor network rollout:■ Multi-antenna system: WiMAX

802.16e supports two mainstream technologies, Multiple Input and Multiple Output (MIMO) and Beamforming (BF), and the typical

Rapid and Economical Deployment of Quality WiMAX Networks


antenna configurations are 2T2R and 4T4R. In most of mobile usage, nomadic/fixed access scenarios, coverage is generally limited by the uplink; therefore, the key is to improve the uplink receiving capacity. The 2T4R and 4T8R configurations can be used to significantly reduce the number of BSs.

■ Introduction of Fractional Frequency Re-Use (FFR): Currently, frequencies available to some WiMAX carriers are 3×10MHz, 3×5MHz or even less. When continuous WiMAX coverage is implemented, there will be a notable inter-cell interference―the cell edge interference is increased by over 3dB. FFR features different frequency duplexing modes for subscribers located in the centers and edges of the sectors, as illustrated in Figure 1. Sector edges (in purple, green and blue) only allow users to operate with a fraction of all available sub-channels to reduce inter-cell interference, and sector centers (in white) allow users to operate with all available sub-channels, to improve spectrum usage.

indoor BSs. ZTE provides the following solution and technology to deploy WiMAX indoor coverage network at a fast speed and low cost.■ WiMAX indoor BSs offer flexible

transmission interface configuration: For fixed-line and cable carriers, the advantage of existing DSL, Ethernet, f iber opt ical cable and cable resources can be fully utilized, and the BSs directly support integration of the corresponding transmission interfaces. For indoor areas without cables or lines, the basic electric wirelines are used for transmission.

■ Considering that emerging carriers and some other carriers have no wired resources in certain cases, 802.16e BSs with self-backhaul and 802.16j-based relay stations are used.

■ Indoor pico BSs and femto BSs use Time over Packet (ToP) technology (see Figure 2), which, through packet transmission and recovery of GPS clock synchronization, solve the problems related to large scale indoor deployment of GPS and WiMAX signal coverage. IEEE1588 is the main industrial standard defining signal flows and the signal transmission framework; however, the clock recovery algorithm is the key to actual performance. The ToP technology has to be adaptive to characterist ics of different transmission media, to meet the synchronization needs of WiMAX.

■ In areas with a higher capacity requirement, multi-carrier pico BSs or distributed BBU and pico RRU combinations may be deployed, to solve network coverage in

early phases of network rollout; and the subscriber growth can be accommodated through baseband capacity expansion in later phases. In the in i t ia l phase , ne twork development will be uniformly planned and the network plan will be gradually implemented to meet user needs during different phases of network deployment.

■ Picocells for indoor coverage support flexible sub-carrier allocation and networking modes , FFR, measurement of signals from adjacent cells and frequency adjustment and optimization, to minimize the interference of indoor coverage.

ConclusionIn te r fe rence min imiza t ion in

combinat ion with mult i -antenna technology can improve outdoor network coverage, reduce the number of outdoor BSs, speed up network building, and ultimately lay a sound foundation for WiMAX development. The indoor network coverage solution takes full advantage of existing transmission resources; takes into consideration wireless self-backhaul and relay standards; solves the difficulties in GPS deployment through packet transmission networks; and reduces the engineering costs through interference minimization technology of macro BSs, which facilitates fast and economical deployment of quality WiMAX networks.

■ Introduct ion of BF: BF is an important technology to minimize uplink and downlink interference through spatial selectivity.

Fast and Economical WiMAX Indoor Coverage Solution

Transmission, timing and engineering deployment are the biggest challenges for 3G mobile carriers in deploying

Figure 1 FFR technology

Sector 1

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Figure 2 Fast and economic WiMAX indoor coverage solution

Research Note


Liu Ping, Lv Qianhao

The Development of SDR Technology

Origin of SDR

In May 1992, Joseph Mitola for the first time proposed the concept of “Software Radio”, also called Software Defined Radio (SDR) at the National Telesystems Conference of the U.S., in the hope to interconnect the multiple frequency bands and multiple operation modes adopted by radio stations of US Navy, Army and Air Force.


Table 1 Phases of SDR implementation

Phase Software Defined Radio Implementation

0 Fixed configured functions, including analog wireless (such as FM) and digital wireless (such as Beep-Pager)

1 Programmable Baseband (such as programmable digital wireless)

2 Programmable Intermediate Frequency (such as Speakeasy of American military)

3 Programmable Radio Frequency, ideal SDR

the hardware circuit. Such software radio station can easily interconnect with the existing or future radio stations.

How to evaluate the grade or phase of SDR implementation? At a SDR conference held in Europe in May 1997, Joseph Mitola raised an idea, which gained wide recognition. His idea is illustrated in Table 1.

SDR-based p roduc t s than f rom traditional ones.

Diversity of technical evolution leads operators into a maze: how to deal with the uncertain network development. Mobile network convergence faces many challenges like coexistence of multiple standards, configuring capacities for different standards, reducing TCO while operating 2G, 3G or B3G networks, and securing service continuity for subscribers. Confronted with these problems, operators find i t hard to work out a successful investment strategy. For operators, construction of a mobile network needs huge investment which involves big risks. SDR, however, can reduce the risks to a certain extent.

From the perspective of end users, SDR-based equipment provides subscribers with a universal terminal platform, which shall support most international standards. The SDR-based equipment can also be upgraded to support new standards with only a software upgrade, helping users achieve real international roaming and obtain new services.

In general, SDR would benefit t h e who le i ndus t ry cha in f rom technical research and development, to equipment manufacturers, telecom o p e r a t o r s a n d e n d u s e r s , t h u s drawing much attention from the telecom industry. The evolution from hardware defined to software defined communications is the third revolution in wireless communications field after the move from analog to digital and from fixed to mobile.

The Base of SDR Commercial Application

The following factors contribute to a natural birth of the SDR base station and open telecom platform.

The basic idea is to create an open, standard, modular, programmable hardware platform, based on which, radio station functions can be realized by adding corresponding software modules. On the universal platform, modification and extension of the radio station functions are done by modifying the software, with no need to redesign

Advantages of SDR The traditional way to develop

products gave rise to many problems. For example, product development was version specific within a specific standard. When a new technology, a new ve r s ion appea r s , o r new services are offered, new chips have to be developed for the production of new generation equipment. This c o n s e q u e n t l y i m p o s e s e i t h e r a restriction on the application of new technology and services, or greater investment risks on operators, and much inconvenience on subscribers.

Meanwhile, the unification of international standards is difficult as there is a variety of economic interests. The increasing standard varieties make frequency allocation and management more difficult as more frequency resource is needed. The production of multi-frequency and multi-mode

handsets is also becoming more difficult with increased costs. SDR, however, introduces a good solution to this problem.

SDR provides a universal radio communica t ion p la t form, based on which , new se rv ices can be delivered and new technology can be used through software update. This consequently results in a substantial reduction in the development costs and cycles and enables the product to keep up with the development of technology.

For equipment manufacturers, investing in a single product line has huge risks. SDR-based products have a lower material cost and a longer product life cycle compared with traditional products, which means less investment risks. Meanwhile, their standardized hardware makes production easy. Thus, manufacturers will benefit much more from producing

Research Note

1�ZTE TECHNOLOGIES January 2009

Presently, SDR is ready for large-scale commercial deployment.

Standard base: 3GPP R7 was official ly released in 2007. Key technologies of HSPA+ and enhanced EDGE were frozen, making it possible to smoothly migrate to OFDM-based 4G technology, which lays a foundation for development of SDR base stations. CPRI and OBSAI standards define an open base station architecture that is highly scalable.

Material base: Mult i -Carr ier Power Amplifier (MCPA) and high speed DSP, as representatives of radio technology, have a highly mature industrial chain after years of development. Meanwhile, extensive commercial applications of multi-carrier technology in WCDMA and CDMA further increase the popularity of MCPA. Thus, while the performance of these two technologies is getting better, their costs are getting lower. This lays the material foundation for the research and development of SDR base station and significantly decreases its cost, which speeds up its commercial development.

Theoretical base: SDR concept was brought forward as early as in 1950s and was extended from military application to civil use. With the speedy development of LSI, high speed DSP theory, and object oriented software architecture in 1980s, SDR exhibited a growing practicability. After 2000, with

theoretical and technical development in broadband MCPA, broadband filter, high speed DAC, universal signal and signaling processing, neural network and intelligence technology, as well as cost reduction, SDR stepped further towards practicality. Discussion over 4G after 2005 clarified the objectives for SDR development. All these provide a solid theoretical foundation for SDR base station development.

U n c e r t a i n t y o f o p e r a t o r deve lopment : Deve lopmen t o f standards provides operators with diversified evolution paths, but it also increases their evolution costs and uncertainty. IP-based services require higher, cheaper bandwidth from the network. Faced with this evolution trend in the industrial chain, operators have to adjust operating strategies and business models and optimize network architectures, so that they can maximally use network resources and agilely handle different service demands. The emergence of SDR makes it easy for operators to cope with uncertainties brought by standard evolution and challenges imposed by multi-service provision. Market demand and profit maximization is the biggest drive for SDR.

Change in competition pattern: Trad i t i ona l t e l ecom equ ipmen t suppliers dominate the present telecom market and act as standard drafters. Unwill ing to be led by vendors,

operators have set up the NGMN initiative to contend with the vendor community. In this sense, SDR is the golden mean concept acceptable by both parties. Furthermore, the camp of emerging vendors led by Intel and Microsoft uses open telecom pla t forms―SDR and ATCA―as powerful weapons to challenge the camp of traditional vendors headed by Ericsson. New forces in the traditional camp like ZTE try to change the present market territory; SDR is one of their forceful weapons.

ConclusionDriven by multi-service convergence

and high-bandwidth demand, mobile broadband convergence and migration to IP network have already become the consensus within the industry. IP-based bearer network and IP softswitch-based core network have been deployed on a massive scale. Presently, promoting commercial trials and deployments of broadband multi-carrier based SDR base stations has also become the consensus among vendors and operators. As to the development and commercialization of this new technology, the gap between different manufacturers has apparently been narrowed. It is foreseeable that development of SDR-based wireless equipment would bring about a more spectacular revolution in wireless communications.


October 2008, by Dimitris Mavrakis (Source: Informa Telecoms & Media)

Overview of SDR Market

Introduction

With the growing number of access technologies and a i r in te r faces , mobile operators are

faced with the daunting task of carefully deploying current networks but also maintaining compatibility with future standards that have not yet entered the market. In developed markets in particular, mobile operators may be faced with radio infrastructure lifecycles of a few years, making it extremely hard

to secure Return of Investment (ROI) for newly deployed equipment since marketing and user adoption always lags technology upgrades. Nevertheless, mobile operators follow predetermined technology evolution paths including GSM to WCDMA to HSPA to LTE, but as technologies evolve, existing hardware that has not been designed for future upgrades has to be replaced or additional overlays need to be added. Especially with LTE which aims to change the air interface from CDMA to

OFDM, existing equipment may have to be completely replaced. However, infrastructure vendors and operators are now looking at Software Defined Radio (SDR) as a way to minimize risk and costs regarding future infrastructure upgrades.

SDR is an umbrella term that covers a plethora of technologies and solutions, ranging from reconfigurable base stations to systems that can adapt to new technologies or new frequencies on the fly without the system suffering any

Third Eye


downtime or users experiencing service interruptions. Although SDR promises several benefits to mobile operators, a cost effective implementation is not without challenges. Indeed, true forms of SDR are only economically viable for military or government applications, but telecoms applications are starting to take advantage of the new concept to give mobile operators a guaranteed evolution path to future technologies.

The Need for SDR SDR presents a new concept for

mobile operators and allows them to have a simpler, more efficient network and in many cases, a guaranteed evolution path to future technologies. In most cases, current base stations need to satisfy several prerequisites to be considered for deployment. Base stations need to: ■ Be wideband enough to be able

to run several air interfaces in the same frequency band. For example, running GSM and UMTS simultaneously at the same frequency in the same hardware platform will provide significant cost savings for operators in emerging markets.

■ Not be constrained to a single waveform. Existing equipment must be upgradable to future air interfaces, either by software or by adding a new baseband processing card to the installed hardware platform. The majority of infrastructure vendors now claim to support LTE through a card addition to their baseband units.

■ Have upgradab le p rocess ing capabilities for future air interfaces. This is especially applicable to LTE, which is expected to require additional processing at the base station due to its low latency, higher bandwidth requirements. Existing

base stations need to be hardware upgradable to more powerful processors.

■ Be environmentally friendly. Power consumption is receiving increasing interest as operators aim to operate “green” networks. Moreover, savings power in the base station will result in far lower operational expenditures. Mobile operators have traditionally relied on running several independent equipment racks for different air interfaces. However, a single hardware platform that can run all of these simultaneously can limit power costs greatly.

In order to satisfy all of the above, base stations need to be reconfigurable and have flexible hardware platforms. A form of SDR is the only solution in the long term and operators are now coming to realize that they can benefit now and in the future by deploying a flexible base station.

Network evolution Mobile operators that have invested

in UMTS and other 3G technologies may now be reluctant to engage in a new round of investments to upgrade their networks to 3G+ or even plan a large investment campaign to rollout LTE on their networks. However, several mobile operators are now finding that their 3G networks are saturating due to increased mobile data usage and that they have to embark on a new upgrade campaign to satisfy existing and short term demand. Effectively, this means that additional hardware equipment will be necessary in base stations and operators must remain aware of new technologies and air interfaces.

Several operators that are now performing capacity upgrades are switching to software reconfigurable base stations in order to either maintain

compatibility with future standards or they have simply found out that an SDR base station will yield performance and financial benefits even in the current market status.

Benefits to mobile operators Desp i t e hav ing a gua ran teed

evolution path and not being tied in to a single technology, operators are presented with several advantages when choosing to deploy SDR. The following list summarizes key benefits for mobile operators. ■ Clearer and simpler network:

Instead of running separate hardware platforms for each technology, operators can have different air interfaces implemented in software on a single hardware platform. Fewer engineers are required since there is a single platform to manage, maintenance and service is also simpler and operational expenditures are kept to a minimum compared to running several hardware platforms.

■ Lower Total Cost of Ownership (TCO), even for existing technologies: Although SDR base stations are typically more expensive than a single technology equivalent, the TCO for a mobile network is many times lower than performing forklift upgrades or hardware upgrades for new air interfaces.

■ Lower investment r isk: Since hardware platforms can be reused, there is significantly less investment r isk for deploying hardware . Moreover, as the SDR market develops, it is expected that some form of standardization will occur, potentially allowing hardware to be reused between different vendors.

■ Competitive network evolution: Mobile operators that have invested in SDR can have a significant


advantage over their competitors that require hardware upgrades to implement a new air interface. Time to market for implementing a new technology is also minimized (assuming that the new technology runs on the same frequency as the hardware platform) since only a software upgrade is necessary to include the new air interface.

Future SDR trends The infrastructure market currently

indicates that additional cost savings and efficiency are required in networks; both are possible with SDR solutions. However, mobile operators are now seeking assurance that SDR base stations will require little capital to upgrade to future standards. Effectively, this means that current SDR solutions will need to evolve in technical efficiency in order for operators to truly regard SDR as a core component of their business model. Chipset manufacturers and infrastructure vendors are working to make SDR a better technology and are focusing on several issues, including:■ Higher bandwidth Power Amplifiers

(PAs) to allow amplifier reuse for several technologies: Current amplifiers are cost efficient up to 20MHz for commercial use, a figure which is far too low to be used for more than one air interface.

■ Higher computa t iona l power for baseband processing: Future technologies, particularly LTE will require higher bandwidth, faster data rates and lower latency, meaning that the computational burden on the base station will be several times higher than today’s implementations. Chipset vendors are now working on faster DSPs and FPGA chipse ts . A fas te r communication bus between these

hardware components is also being developed, as the communication between the hardware components is now proving to be the processing bottleneck.

■ Baseband processing to take place in RF: This is the ultimate SDR concept, meaning that all aspects of the base station are implemented in hardware and the power amplifier will be the only component that remains in hardware. This will mean total reconfigurability and upgradeability but is currently not possible for 3G frequencies and certainly not cost efficient. Research organiza t ions have performed this up to 800MHz but are now discovering that there is a critical limit in moving to higher frequencies, due to the unavailability of such high bandwidth RF components and the computational complexity required.

Evolution to LTE The majority of mobile operators

have now declared that they believe LTE will be the technology of choice for the future. The vision for the evolution of HSPA to Evolved HSPA and eventually to LTE is now dominating the market and it is clear that LTE will be the preferred 4G standard.

Mobile operators that are upgrading their networks to new technologies or adding further capacity will be aware that current hardware may have to be replaced in order for LTE to be deployed. Although SDR may alleviate some of these concerns, there are still issues to be resolved regarding LTE.

Firstly, mobile operators are not yet clear when LTE will be necessary in the market and secondly, it is unclear what spectrum will be used for the deployment of LTE. Nevertheless, it

is expected that 2009 will be integral for operator strategies, and 2010 will see initial networks being rolled out in small scales. SDR is expected to be a major component of mobile operator s t rategies for LTE, as operators will come to realize that a scalable and eff icient hardware platform i s necessary to main ta in fu ture compatibility, achieve lower TCO and remain competitive when air interfaces are updated.

SDR Value Chain The SDR value chain is characterized

by few p layers , mos t ly ch ipse t manufacturers and infrastructure vendors. Both are innovating in the evolution of the technology, but vendors usually provide the necessary expertise and manpower to package powerful hardware platforms into upgradeable base stations. The following diagram illustrates the SDR value chain.

Chipset manufacturers are providing faster DSPs and FPGAs that can run current and future algorithms. DSPs are usually used to calculate specific parameters which are fed through to FPGAs that actually run the algorithms. The latter are actually considered the most powerful computational platforms in 3Q 2008 and are expected to remain so in future SDR implementations.

Figure 1 SDR value chain

Source: Informa Telecoms & Media

Third Eye


Infrastructure vendors are using these components in a variety of hardware platforms in order to implement their versions of SDR base stations. The baseband processing is the heart of the base station and is usually based on a proprietary, vendor specific implementation that follows the standard dictating the air interface. Several Tier-1 vendors have started offering SDR base stations, including ZTE and NSN.

Infrastructure Vendors The majority of infrastructure

vendors have included reconfigurable b a s e s t a t i o n s i n t h e i r p r o d u c t lines, and are currently (during 3Q 2008) promoting their cost savings capabilities, more efficient operation of the network, environmentally friendliness and future upgradeability. The following table illustrates base station offerings by the top five infrastructure vendors that include some form of reconfigurability.

ZTE is one of the first vendors to launch a SDR base station that can be upgraded to LTE though a baseband add-on and software upgrade. Several other vendors have followed and are now launching or have already launched SDR base stations. The form of SDR implementation in base stations varies and each vendor may have

chosen a different level of commitment for software reconfigurability. ZTE and Huawei are the only vendors that support dual mode GSM/UMTS operation in their base stations; ZTE has released the platform first.

ZTE claims that its base station platform saves up to 40% on power costs by using a high efficiency power amplifier and has an almost 30% lower TCO for mobile operators that deploy a SDR solution rather than a standalone base station. ZTE is also planning to continuously evolve its product line to offer advanced base stations for mobile operators, inc lud ing dua l and mul t i mode products that operate several air interfaces in one hardware platform.

Operator Views

Several operators are currently assessing the feasibility and cost savings that SDR can offer to them and are starting to include the new concepts in their networks. Flagship network operators, including Vodafone Spain, Hong Kong CSL and others, are proving that SDR can increasingly save costs in the network and are acting as greenfield attempts for SDR. Although the majority of mobile operators are now deploying SDR fo r fu tu re upgradeab i l i ty, Hong Kong CSL has consolidated

hardware from several infrastructure vendors into a single platform and is now operating a much more cost effective network.

HK CSL case study CSL is the largest

operator in Hong Kong with more than 3 million s u b s c r i b e r s i n 3 Q 2008. It operates GSM

Table 1 Major infrastructure vendors' SDR products

Source: ZTE, Huawei, Ericsson, NSN

and UMTS networks under several commercial brands and is a subsidiary of Telstra, Australia’s leading telecoms operator.

CSL has been operating a large, complex network with over 2000 sites that were built on hardware from different infrastructure vendors. This has eventually resulted in a large scale complex network that was difficult to manage, required separate support and transport platforms, different radio access layers and a complex hardware infrastructure. Moreover, there were limited opportunities for network evolution, since network upgrades would have to rely on a multi-vendor effort that would be very expensive.

CSL has chosen ZTE to replace existing hardware with a single, expandable and efficient SDR platform that can be easily managed. CSL has replaced multi-vendor hardware with a single platform that runs both GSM and UMTS simultaneously, leading to a much more efficient and simple network. A single hardware platform was used, with different Radio Remote Units (RRU) for each frequency that were placed near the antenna (distributed base station) for additional RF cable savings.

Although CSL has made a large investment, it has thus ensured future compatibility with HSPA and LTE without compromising its current offerings. Savings in operational expenses are expected to offset the initial capital expenditures within a short timeframe. While SDR is deployed here as a way to save costs on the current network, the CSL deployment demonstrates that mobile operators wishing to make their current networks more efficient will be able to do so with SDR.


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ZTE’s HSPA+ SolutionZhang Yiqian

Solution

High Speed Packet Access E v o l u t i o n ( H S PA + ) refers to a set of HSPA enhancements specified in

3GPP R7 and beyond. It is a step in the evolution of WCDMA technology; it upgrades the HSPA network in an effort to be as close as possible to achievable LTE performance.

Principles of HSPA+ Different from LTE, HSPA+ does

not seek creating a brand new network using new technologies; instead it improves HSPA through introducing

new technologies, so that operators can continue to evolve after deploying HSPA. Before LTE technology becomes mature and commercialized, HSPA+ enables operators to achieve performance comparable to LTE at a relatively small upgrade cost, fully protecting operators’ investment. The key technologies of HSPA+ include higher order modulation, Multiple-Input Multiple-Output (MIMO), combination of 64QAM and MIMO, advanced receiver, Continuous Packet Continuity (CPC), Enhanced Cell Forward Access Channel (FACH) and access network architecture optimization.

ZTE’s HSPA+ SolutionZTE’s HSPA+ solution is able

to offer high performance HSPA+ processing capabilities with a software upgrade. It also supports the upgrade to LTE or UMTS/LTE dual mode, helping operators realize smooth evolution of network at a low cost. It has the following characteristics: ■ Smooth evolution with software

upgradeThe UTRAN equipment provided

by ZTE can be software upgraded to HSPA+ without hardware change, ensuring smooth upgrade for operator

10101010101010101R99/HSPA

64QAM HSPA+ or MIMO HSPA+

LTE or UMTS/LTE


while lowering CAPEX.For HSPA+ a t the f i r s t s t age

(64QAM), when the system does not provide the MIMO function, as shown in Figure 1, the base station system can be upgraded to 64QAM HSPA+ by upgrading the software of the baseband board. The 64QAM mode enables a maximum downlink rate of 21.6Mbps and a maximum uplink rate of 11.5Mbps.

For HSPA+ in the second stage, when the system provides MIMO function, the base station system can be upgraded to HSPA+ with 2×2 MIMO by upgrading the software of the baseband board and adding an RRU or RSU module to each RF sector. MIMO in combination with 64QAM provides a maximum downlink rate of 42Mbps, and the introductin of 16QAM s the maximum uplink rate to reach 11.5Mbps.■ A d v a n c e d S D R t e c h n o l o g y

supporting software upgrade to LTE or UMTS/LTE

power management technology, which faciliates more efficient power consumption of NodeB under different loads, perfectly satisfies operator’s demands for energy saving. Therefore, operator’s network construction cost and TCO can be effectively decreased.

ConclusionDuring the life cycle of 3GPP

standard, technologies keep developing, protocols keep evolving, and product functions keep upgrading. With the exponential growth of data traffic, operators with mature networks are eager to improve equipment capabilities, enhance wireless spectral efficiency and increase transmission bandwidth. However, due to the fact that mobile technologies develop rapidly, and that network upgrade or reconstruction will incur huge expenditure, operators are forced to lower the TCO within the life cycle of their equipment, and many high-end operators have very strong demands for the smooth upgrade of network. Therefore, HSPA+ will surely become a powerful weapon for operators in the 3G era to compete on data services.

ZTE’s HSPA+ solution is designed at the very beginning to provide o p e r a t o r s w i t h t h e m o s t c o s t -effective network deployment and evolution scheme. Its new generation base station products have higher performance, higher integration and higher expandability, and they can be software upgraded to support HSPA+ as well as upgraded to support LTE or UMTS/LTE dual mode, meeting opera tor ’s demands for smooth upgrade at a low cost , enabl ing operators to construct high-quality 3G networks as quickly as possible with reduced network CAPEX and OPEX.

Figure 1 Upgrade to HSPA+ at the first stage (64 QAM)

Software upgrade

R99/HSPA HSPA+(64QAM)

No change

WCDMA BP WCDMA BP

Software upgrade

R99/HSPA64QAM HSPA+ or2*2MIMO HSPA+ LTE or UMTS/LTE

No change Software upgrade

Add LTE BP

LTE BPWCDMA BP WCDMA BP

Figure 2 A single RRU software upgraded to support HSPA+, LTE or UMTS/ LTE

Software upgrade

R99/HSPA HSPA+(64QAM)

No change

WCDMA BP WCDMA BP

Software upgrade

R99/HSPA64QAM HSPA+ or2*2MIMO HSPA+ LTE or UMTS/LTE

No change Software upgrade

Add LTE BP

LTE BPWCDMA BP WCDMA BP

ZTE’s advanced SDR technology supports the software upgrade of HSPA+ (MIMO) to LTE or UMTS/LTE dual mode, meeting operator’s demands for smooth evolution to LTE. During the upgrade, it is only necessary to add new LTE BP boards.

Additionally, ZTE has planned a type of Radio Remote Unit (RRU) that supports 2T2R, which will be released in 3Q 2009. A single RRU can support MIMO. There is no need to replace any hardware for RRU in the upgrade from HSDPA to 64QAM, MIMO, LTE, or UMTS/LTE dual mode (Figure 2). With a mere software upgrade, operators get better network performance.■ New generation base stations,

effectively reducing HSPA+ network construction cost and TCO

The breakthroughs made in key technologies of base station, such as large-capacity baseband board, digital pre-distortion, power amplifier with 40% efficiency, and multi-carrier SDR RF module, enabled the new generation base station products of ZTE to have such advantages as smaller volume, lighter weight, better price peformance ratio, and stronger expandability, which help o p e r a t o r s a v e l a rg e a m o u n t o f investment in installing equipment room and supplementary equipment. Moreover, the unique intell igent


Solution

Huang Xuan, Xie Weihao

IntroductionC D M A 2 0 0 0 i s a 3 G m o b i l e

communications standard evolving from the IS-95A/B standard, and 3GPP2, one of the two international wireless technology standardization organizations, is responsible for its standardization. The development of CDMA2000 is divided into two stages: CDMA2000 1x (including Release 0 and Release A) launched at the first stage focuses on improving voice capacity and delivering relatively low rate packet data; CDMA2000 1xEV-DO, also called High Rate Packet Data (HRPD), launched at the second stage aims to enhance data services.

CDMA2000 1xEV-DO includes DO Rel.0 and DO Rev.A that have been put into commercial use, as well as the subsequently launched DO Rev.B and DO Rev C. Within the 1.25MHz bandwidth, DO Rel.0 provides a peak downlink data rate of 2.4Mbps and a peak uplink data rate of 153.6Kbps, while DO Rev.A delivers a maximum downlink data rate of 3.1Mbps and a maximum uplink data rate of 1.8Mbps. Moreover, DO Rev.A uses multiple techniques to increase radio capacity, lower system delay and introduce QoS management, thereby significantly improving user experience while supporting real-time services such as high-quality VoIP and Video Telephony (VT). Therefore, DO Rev.A has become a mainstream technology of choice in the CDMA2000 1xEV-DO market.

Problems Facing EV-DO Rev.AThe global 3G networks have

developed rapidly in recent years. The annual growth rate of network capacity from 2005 to 2008 is over 100%. The 3G technologies that are applied most extensively are 3GPP HSDPA and 3GPP2 EV-DO Rev.A, so in many countries these two networks are in a competition.

With many technical enhancements, DO Rev.A is capable of providing varieties of services including VoIP, VT and other real-time services. But the overwhelming applications of DO Rev.A still lie in the simplest wireless data services. According to the sampling statistics, web browsing, FTP and other data services account for 50%, 40% and 10% of its applications respectively, and this is the same case with HSDPA.

The two key indices of wireless data services are system delay and downlink rate. The average system delay of DO Rev.A is lower than 50ms and that of HSDPA is about 120ms, so in this aspect DO Rev.A is superior to HSDPA. However, DO Rev.A provides a maximum data rate of 3.1Mbps on the downlink, while, theoretically, HSDPA can provide downlink data rates as high as 14.4Mbps, so HSDPA has a great advantage over DO Rev.A, though currently it can only reach the peak data rate of 7.2Mbps due to the capability restraint of terminals. From the prospective of market development, high data rate is more attractive than low delay. Under

similar tariff conditions, users tend to choose the network with a higher data rate, and the higher data rate is convenient for telecom operators to offer flexible charging policies.

Besides, there is another important technical problem. Although both CDMA2000 1x and DO Rev.A belong to the CDMA2000 family of standards, DO Rev.A cannot implement soft handoff, that is, it cannot get a macro diversity gain in an intra-frequency network. In this case, intra-frequency interference between cells is relatively large, and the data rate in the edge of the cells will be greatly impacted. This is also the reason why intra-frequency networking is avoided in GSM system.

Enhanced EV-DO Rev.A SolutionLow peak data rate and poor service

experience for edge users are major problems with EV-DO Rev.A. To solve these problems, it is advisable to introduce the enhanced EV-DO Rev.A solution, which has the following attractions:

Multi-carrierIn the enhanced EV-DO Rev.A

solution, data can be segmented into multiple lower data rate flows and then re-assembled into a high data rate flow. As shown in Figure 1, the BSC divides the forward data into three channels, and sends them to one or multiple BTSs. Via the air interfaces, the BTS transmits the data over three carriers independently to

Making a More Competitive CDMA2000―An Enhanced EV-DO Rev.A Solution


Carrier 1Carrier 2Carrier 3 PDSN

Internet

FORWARD LINKMEDIA

SERVER

High Data Rate FlowBSC:

DEVICE:Re-assemble into

high data rate flow

PDSN

Internet

REVERSE LINK

BSC:

DEVICE:

HIGH DATA RATE FLOW

BTSBSC

Carrier 1Carrier 2Carrier 3

BTSBSC

MEDIASERVER

Segmentation into multiple lower data rate flows

Re-assemble intohigh data rate flow

Segmentation into multiple lower data rate flows

Carrier 1

Carrier 2

Carrier 3

Edge areas of Carrier 1 Edge areas of Carrier 2 Edge areas of Carrier 3

Figure 2 Interleaved coverage

Figure 1 Multi-carrier transmission of enhanced EV-DO Rev.A

the terminal. After receiving them, the terminal re-assembles the three data flows into a high data rate flow. In the reverse link, the principle is similar except that the BSC re-assembles the backward data.

Using such a multi-carrier transmission mode, the data rate for a single terminal user can be up to three times that of the original EV-DO Rev.A, with a peak data rate being increased to 9.3Mbps.

Interleaved coverageIn traditional CDMA2000 1x and

CDMA2000 1xEV-DO networks, there is a common concept that different carriers under the same cell provide the same coverage. Therefore, the relative standards, network planning and cell handoff are all designed in accordance with this concept. Such design has no

problem with CDMA2000 1x, because it has soft handoff function. But in order to bring better service experience to edge users in CDMA2000 1xEV-DO, it is necessary to challenge the conventional idea, that is, to allow different carriers to have different coverage.

As shown in Figure 2, different carriers adopt different coverage. The edge areas of Carrier 1 are not edge areas for Carrier 2; the edge areas of Carrier 2 are not edge areas for Carrier 1. In this way, wherever the terminal is located, it is always possible to choose the most suitable carrier that can deliver better service, thereby avoiding poor service experience for edge users.

Implementation The implementation of the enhanced

EV-DO Rev.A involves the network side and the terminal side.

The network side focuses on the upgrade to the enhanced EV-DO Rev.A. For a single-carrier EV-DO Rev.A network, it is necessary to add carriers and upgrade network software. The process of adding carriers can be completed simply by upgrading relative software, for most of the existing network devices are multi-carrier components; the network software upgrade is implemented in two parts: BSC and BTS. For multi-carrier EV-DO Rev.A network, it is only necessary to upgrade software. The interleaved coverage can be implemented in several methods, such as using the GSM frequency reuse networking mode, or adopting different carriers of different powers in some areas, or adopting different antennas for different carriers. Telecom operators can determine the specific methods according to their conditions, such as spectrum resources, equipment investment, and user growth.

The terminal side needs to support multi-carrier EV-DO Rev.A. As the enhanced EV-DO Rev.A is ful ly compatible with the original EV-DO Rel.0 and EV-DO Rev.A, the original EV-DO Rel.0 and Rev.A terminals can run smoothly under the enhanced EV-DO Rev.A network. In this case, multi-carrier terminals can be gradually introduced.

ConclusionIn today’s f ie rce compet i t ion

of wireless broadband business, CDMA2000 1xEV-DO Rev.A no longer has competitive edge. The enhanced EV-DO Rev.A solution is an ideal choice for telecom operators, for it can be implemented simply by upgrading software of the existing network and will greatly improve network competitiveness with a relatively small investment.


Moving Towards Convergence ―ZTE core network convergence solution

Pan Zhenchun

Solution

Problems Faced by CDMA Operators During Dual Network Operation or Migration

In the markets like America, South Asia and Africa, CDMA operators have captured considerable market shares, with fully developed

voice and EV-DO based data services. However, the CDMA networks do not have wide coverage and plenty of terminal types as GSM/UMTS networks. Therefore, many CDMA operators have chosen dual network operation, i.e. operating both CDMA and GSM/UMTS networks at the same time; or opted for the migration path from CDMA to GSM/UMTS. These operators may be confronted with the following problems:■ Building and maintaining two

sets of core network facilities for CDMA and GSM/UMTS networks r e s p e c t i v e l y r e q u i r e s m o r e

equipment room and consumes more energy.

■ Simultaneous management of two kinds of subscriber data requires two types of interfaces to OSS.

■ CDMA and GSM/UMTS subscribers can not share the same number segment. Number portability between CDMA and GSM/UMTS networks is a necessity and hard to implement.

■ Two network management systems and two teams of maintenance staff are required.

■ Two sets of service platforms including two SMSCs and two SCPs are required.

As the leading provider of CDMA and GSM/UMTS core networks and wireless equipment, ZTE has put forward the core network convergence solution (see Figure 1) to solve these problems.

Figure 1 ZTE convergent core network

All-IP Bearer Network

SCP MMS

VMS

VAS OSS

SMS

MSCS/MSCe ConvergentHLR/AAA uMGW

UMTS GSM CDMA

ZTE Core Network Convergence Solution■ Convergent MGW for resources

sharing and lower TCO ZTE’s Media Gateway (ZXUN

uMGW) supports simultaneous access to both CDMA and GSM/UMTS, implementing equipment resource

ZTE Core Network

2�ZTE TECHNOLOGIES January 2009

sharing of the two networks. The allocation of resources within MGW can be adjusted at anytime according to the network capacity of CDMA and GSM/UMTS networks, thus avoiding capacity expansion resulted from the migration of subscribers between two networks.

The ZXUN uMGW supports the codecs of both CDMA and GSM/UMTS networks. Accordingly, any of these codecs can be chosen for communicat ions among MGWs, reducing unnecessary codec conversion and saving transcoder resources.

MGW is the most common network element in the core network. It enables equipment resource sharing and reduces the amount of hardware, the space occupancy and power consumption of equipment. Moreover, one convergent MGW only needs one set of LMS and one set of IP networking equipment. All this will save TCO for operators.

■ Unified user data management and interface

ZTE convergent HLR is based on its proprietary USPP platform. The HLR with distributed architecture can realize N+K geographical disaster recovery. It adopts LDAP protocol to store and manage the CDMA and GSM/UMTS subscriber profiles at the same time. Moreover, it provides unified OSS interface. The transfer and modification of the CDMA and GSM/UMTS subscriber profiles use the same MML interface and the same MML commands. Operators do not have to develop or maintain two sets of OSS interfaces for CDMA and GSM/UMTS networks respectively.

In addition, ZTE USPP platform is a universal platform for user data management. The AAA functionalities o f C D M A s y s t e m a n d t h e H S S functionalities of IMS domain can also

be integrated into the USPP platform together with the HLR, thus further reducing the investment in equipment for operators and simplifying the network architecture.

■ Convergent HLR enabling free migration of subscribers

In the convergent HLR, CDMA and GSM/UMTS subscribers share the same MDN/MISDN number segment, and there is no need to use different number segments to differentiate network types of subscribers.

The convergent HLR supports the MAP protocol for CDMA and GSM/UMTS respectively. It also supports the switching between two MAP protocols according to network types of calling and called users, so it truly implements number portability between CDMA and GSM/UMTS networks. Subscribers who want to switch networks do not need to change their mobile phone numbers, so the user satisfaction is improved.

■ Unified network management system simpli fying network management and saving OPEX

Convergent core network requires unified network management. ZTE’s Ne tNumen cen t ra l i zed ne twork management system can manage all network elements in both CDMA and GSM/UMTS core networks at the same time, and provides all functionalities such as configuration management, fault management, performance management and security management. Furthermore, it can manage affiliated network equipment for networking, such as routers, firewalls and Ethernet switches.

The highly centralized network management reduces the manpower of network maintenance and management for operators, thus saving the operation and maintenance costs.

■ Convergent service platform for unified service provision and management

ZTE provides CDMA/GSM/UMTS operators with a convergent service platform, which includes facilities such as Short Message Service Center (S M S C) , S CP, and M u l t imed i a Message Service Center (MMSC).

The convergent SMSC supports MAP protocols for both CDMA and GSM/UMTS networks, and it delivers short message service to both networks. The convergent SCP supports two intelligent network protocols: WIN for CDMA network and CAMEL for GSM/UMTS network, and it provides intelligent services to both networks.

ConclusionFor operators who need to operate

b o t h C D M A a n d G S M / U M T S networks, ZTE’s convergent core network solution is an optimization scheme that can bring significant CAPEX and OPEX savings.

The solution provides multiple advantages: sharing of software and hardware resources within both CDMA and GSM/UMTS core networks, unified user data management and OSS interface, sharing of number resources to enable free migration of subscribers between both networks, unified network management to save costs, convergent service platform for unified service provision and management.

To sum up, ZTE core network convergence solution lowers the costs of dual network operation. In addition, it also provides a convenient way for operators to migrate from CDMA network to GSM/UMTS network, solving many problems confronted by operators during this process.


ZTE Assists Hong Kong CSL in Achieving ExcellenceHu Haosi, Yan Haibo

Case Study

Established in 1983, CSL is one of the leading mobile operators in Hong Kong with more than 2.65 million

subscribers. CSL is paying much attention to network construction so that user service experience is constantly improved by virtue of the most cutting-edge technology and outstanding engineering technology. CSL was the first mobile company in Hong Kong to launch GPRS services in 2000, and also the first to deploy EDGE technology in 2003. At the end of 2005, CSL acquired the Hong Kong-based operator NWM, and became the largest mobile operator in Hong Kong. This acquisition enabled CSL to not only have 2.65 million mobile subscribers in total but also inherit four original networks of the

former two companies, namely, one GSM900 network, two GSM1800 networks and one UMTS2100 network. The main objective of such acquisition was to make the new joint-venture company achieve cost reduction and gain stronger competitive edge. However, the four networks of dual modes and three frequency bands became obstacles that prevent further development of CSL.■ Overlapped resources: The two

GSM1800 networks resulted in high maintenance cost.

■ Poor upgrade: The 3G data services of existing networks provided only 1.8Mbps downlink data rate and could not support software upgrade. Higher downlink data rate can be only achieved with large investment

in hardware upgrade. ■ Complicated network architecture:

It is hard to implement network convergence and evolution due to the coexistence of multiple modes and multiple frequency bands.

CSL Selected ZTE as A Partner C S L w a s i n u r g e n t n e e d o f

reconstructing its four networks into a single network with good quality and continued evolution. After a period of market research, CSL finally selected ZTE’s convergence network solution based on SDR platform.

The biggest difference between SDR base stations and conventional base stations is that the Radio Remote Unit (RRU) of the former can be software programmable to implement intelligent


spectrum allocation and support various systems including GSM/WCDMA/LTE simultaneously. The Baseband Unit (BBU) adopting unified MicroTCA platform features small size, low power consumption, standard modules and strong scalability, and it can process various GSM/WCDMA/LTE baseband signals. ZTE proposed using one 2G/3G convergence network to replace the original four networks and to implement unified management. The convergence network can support HSPA+ through software upgrade and the evolution to LTE at low cost.

SDR-based Network Convergence Solution

Many skysc rape r s and dense population in Hong Kong resulted in complicated wireless environment; reconstructing of 2G/3G convergence network under such circumstances was a challenging task. The following solutions have been found:

BBU+RRU distributed networking to save equipment room

Being only 2U in he ight , the BBU can be mounted on the wall, or embedded in the transmission rack or GSM equipment rack. The RRU is the smallest and lightest one in the industry, with IP65 protection against harsh environments. It can be mounted on the wall, pole and tower top as required. Through the BBU+RRU distributed networking, ZTE made full use of the limited space of original sites, helping CSL save considerable rentals of equipment room.

Combination of multiple RRU cells to guarantee good user experience

The wireless environment in Hong Kong is very complicated. Due to the sheltering and isolation of high-

rise buildings, multiple directions of antenna coverage are required in many areas. To ensure good coverage, ZTE deployed multiple RRUs to provide independent RF signals and power amplification for each direction. Moreover, ZTE adopted the innovation technology of combining multiple RRU cells into one logical cell, thus greatly reducing handoffs in certain areas and effectively improving service experience of terminal users.

High-performance multi-band antenna to reduce O&M cost

Due to the complexi ty of the existing network structure of CSL, many sites had antennas of different modes. The isolation condition could hardly be satisfied as new antennas would be added, and CSL would pay considerable rentals for each additional antenna pole. Judging from this situation, ZTE proposed to use high-performance multi-band antenna (900/1800/2100MHz tri-band antenna) to replace the existing antennas of various networks. The application of high-performance multi-band antenna not only ensured good coverage, but also facilitated the subsequent network cutover. Moreover, it helped CSL greatly reduce Operation and Maintenance (O&M) cost.

Efficient and all-round service to improve customer satisfaction

As CSL leased the IP network provided by the third party for most of its transmission between the base stations and the Radio Network Controller (RNC), ZTE specifically customized the network management system by adding two functions: QoS monitoring of the third party’s IP network and remote management of Network Elements (NEs) via VPN. By using the NEs’ existing

functions and newly-added performance management and alarm management functions, the QoS of IP transmission network can be effectively monitored. Network management over VPN, an innovative feature developed by ZTE, guarantees security of management data and saves rentals of IP network as the NEs only occupy private IP addresses. In this way, the O&M staff of CSL can sit at home to control the indoor temperature of a certain remote equipment room. The highly personalized, unified and integrated network management system offered by ZTE significantly reduced TCO for CSL.

Recognition from CSLThe CSL network reconstructing

project was an arduous and complicated undertaking for it involved replacement of all existing network devices. CSL worked closely with ZTE to make a detailed implementation plan. ZTE set up a special project team consisting of over 300 engineers and technical professionals responsible for execution, monitoring and management of the project.

The success of HLR cutover on August 27, 2008 was the milestone that ZTE’s equipment officially began to serve CSL’s subscribers. At present, the construction of CSL Phase 2 project has been initiated.

ZTE took into consideration every detail of the implementation plan and won recognition from CSL in respect of QoS, O&M cost and technology evolution. Upon the completion of Phase I project, CSL held a celebration party to honor ZTE staff for their outstanding performance and all-round service. The two parties are expected to further their cooperation and jointly build a cutting edge 3G network.

Documents

Preface - ZTE...Executive Vice President of ZTE: Tian Wenguo January 1st, 2009 Preface Moving Steadily Through the Storm T he global financial storm caused by the U.S. subprime loan