SATTELITE COMMUNICATION TECHNOLOGY AND ITSRELEVANCE IN NATIONAL DEVELOPMENT

BY

KADIRI, KAMORU OLUWATOYIN

FEDERAL POLYTECHNIC, OFFA KWARA STATE NIGERIA.

DEPARTMENT OF ELECTRONICS/ELECTRICAL.

Kadiritoyin2007@yahoo.com

ABSTRACTThis seminar paper discusses Satellite Communication and it’s

relevant in National Development. It reviewed various satellite

communications connectivity and makes a comparison among the

three types of VSAT Satellite Communication services on C band,

Ku band and Ka band. Statistical methods of data collection such

as interview method, transcription from records were used to

gather information from the subscribers in order to know their

preference among these three frequencies.

KEYWORDS: C band, Ku band, ka band, microwaves, communication,satellite, VSAT

INTRODUCTION

Wireless Transmission

In wireless transmission, various types of electromagnetic waves

areused to transmit signals. Radio transmissions, satellite

transmissions,visible light, infrared light, X-rays, and gamma

rays are all examples ofelectromagnetic waves or electromagnetic

radiation. In general,electromagnetic radiation is energy

propagated through space and,indirectly, through solid objects in

the form of advancing disturbance ofelectric and magnetic fields.

The basic difference between various typesof electromagnetic

waves is their differing wavelengths, or frequencies

Terrestrial microwave

Transmit tightly focused beams of radio signals from one-ground-

basedmicrowave transmission antenna to another. The two most

commonapplication areas are telephone communications and

businessintercommunication. The approximate distance between

towers isbetween 20 -30 miles. The higher the tower, the farther

the possible transmission distances. It is to be noted that

signals will not pass throughsolid objects. Terrestrial microwave

transmits data at hundred of

millions of bits per second. Microwave antennas use line-of-

sitetransmission, which means that to receive and transmit a

signal, eachantenna must be in sight of the next antenna as shown

in figure 2. Thedisadvantages of terrestrial microwave can

include loss of signalstrength (attenuation) and interference

from other signals(intermodulation), in addition to the costs of

either leasing the service orinstalling and maintaining the

antennas.

Satellite microwave transmission

These transmission systems are similar to terrestrial microwave

systemsexcept that the signal travels from ground station on

Earth to a satelliteand back to another ground station on Earth,

thus achieving muchgreater distances than Earth-bound line-of-

sight transmissions. One way

to categorizing systems is how far the satellite is from the

Earth. Thecloser a satellite is to the Earth, the shorter the

times required to senddata to the satellite(uplink) and receive

data from the satellite(downlink) .This transmission time from

ground station to satellite andback to ground station is called

propagation delay. Satellites can beclassified by how far out

into orbit each one is (LEO, MEO, GEO, andHEO). LEO –Low Earth

Orbit --100 to 1000 miles out. Used for

wireless, e-mail, special mobile telephones, pagers,

spying,videoconferencing. MEO -Middle Earth Orbit -1000 to 22,300

miles.Used for GPS (global positioning 'systems) and government.

GEO-Geosynchronous Earth Orbit -22,300 miles. Always over the

sameposition on earth (and always over the equator).Used for

weather,television, government operations.HEO -Highly Elliptical

Earth orbit.

Fig. 1 Satellite Communications

VSAT Satellite Communications Connectivity

VSAT stands for Very Small Aperture Terminal which is basically a

small satellite antenna (less than or equal to 4.5m diameter) as

opposed to a large antenna. The word terminal refers to the fact

that the antenna is attached to a system that can transmit and

receive through the antenna to and from a satellite. This seminar

paper presents satellite communications and its relevant to

National development [9]

Ku Band versus C Band Satellite Service

Ku-band

The Ku frequency is designated solely for communications use via

satellite. That means no competition or signal interference from

other communications systems.

Typically, the Ku band operates at a higher frequency (11.7 -

12.2Ghz) for downlinks and (14.0 - 14.5Ghz) for uplinks. This higher

frequency produces a signal with a shorter wavelength that's more

powerful and focused.

With greater power and a more focused signal, a smaller satellite

dish can be used to receive service. Usually all that's needed is

a 1.2 or 1.8 meter dish for most locations. That's about 4 or 6

feet in diameter, depending upon the service location in relation

to the satellite delivering the signal.

Consequently, the ku-band is excellent in delivering spot beam

coverage from the satellite. The downside is the service coverage

area is not as broad as C-band. Additionally, the higher

frequency spectrum of Ku band operation makes this service more

likely to be affected (usually from atmospheric conditions) by signal

degradation than C-band satellite service.

Ku-band satellite equipment costs about half as much as C-band

equipment. Also, because Ku service utilizes more powerful

transponders on the satellite for operation, bandwidth capacity

is more expensive which means that ku band service packages

generally cost more.

C-band

C-band, on the otherhand, operates at a much lower frequency (3.7 -4.2 Ghz) for downlinks and (5.9 - 6.4Ghz) for uplinks offering a wider coverage area.

One disadvantage of C-band satellite service is that it shares the same frequency as terrestrial microwaveradio systems. As a result, some VSAT locations may be restricted so as not to interfere with these radio systems (i.e.- mobile phones).

The C-band frequency employs a larger satellite dish. For most locations, usually 2.4 meters (about 8 feet in diameter), is sufficient to receive service. But ...for some locations around the world, antennas as large as 3 to 3.7 meters (about 10 to 12 feet in diameter) maybe required to receive C-band satellite service.

Two factors are considered in this determination, geographic location in relation to the servicing satellite and local atmospheric weather conditions. As a rule of thumb, locations subject to heavy rains or snowfall usually require larger dish antennas.

The biggest advantage of a larger dish is that it offers minimal interference from severe weather conditions resulting in consistent, reliable service for practically any location. The downside - how do you make a satellite dish this large look inconspicuous? [9]

KA band   The focus of KA focus is to provide a comprehensive range of

flexible Broadband service packages with Hight-speeds, best

prices and excellent service levels tailored to meet individual

user and market conditions.

The Ka band (Pronounced: "Kay-Ay Band") covers the frequencies

of 26.5–40 GHz, i.e. wavelengths from slightly over one

centimeter down to 0.75 centimeters. The Ka band is part of the

K band of the microwave band of the electromagnetic spectrum.

This symbol refers to "K-above" — in other words, the band

directly above the K-band. The 30/20 GHz band is used in

communications satellites, uplink in either the 27.5 GHz and

31 GHz bands, and high-resolution, close-range targeting radars

aboard military airplanes. Some frequencies in this radio band

are used for vehicle speed detection by law enforcement. [12]. 

Some of the VSAT Applications

BANKING

Applications

ATM Teller Services Branch Bank Automation Transaction support File/Software updates Electronic Benefit

Transfer Employee Training

Benefits

Superior Availability Single Platform for

Multiple Applications Easy Installation Supports Growth Acquisition Quick ATM Response Full Time Connectivity Trained Staff

ENERGY

Applications

Pipeline Monitoring Powerline Monitoring SCADA Communication to

Drilling Sites

Benefits

Superior Availability Reduced Data

Acquisition Cycles Easy Installation Minimal Maintenance Secure Transmissions Links Inaccessible

Sites Extremely Cost

Effective

FINANCIAL SERVICES

Applications

Brokerage Service On-Line Trading Trade Settlements Bank Branch Automation ATM Teller Services Electronic Payment

Transactions File/Software Updates

Benefits

Superior Availability Quick Execution of

Orders Shorter Settlement

Cycles Faster Credit

Authorization Quick ATM Response Secure Transmissions Full Time Connectivity Anywhere

HOTELS

Applications

Credit Authorization Reservations Property Management Inventory Control Frequent Traveller

Programs E-mail

Benefits

Improved Customer Service

Supports Multiple Payment

Options Improved Asset

Management Additional Revenues Improved Yield

Management Supports Growth &

Acquisition

RETAIL STORES

Applications Benefits

Credit Authorization Point-of-Sale Pricing Updates Frequent Buyer Programs Inventory Control Video Promotions Video Training

Speeds Up Payment Time Supports Multiple

Payment Options Accurate Price Updates Improved Customer

Service

TRANSPORTATION

Applications

Inventory Control Fleet Management Shipment Tracking Inventory Control Invoicing Delivery Reconciliation Credit Authorization Order Entry

Benefits

Improved Customer Service

Effective Inventory Control

On-line Shipment Tracking

On Time Deliveries Manage Rental Fleets Full Time Connectivity Superior Availability

SCOPE OF THE STUDY

This seminar paper is concerned with the relevance of satellite

communication in national development.

STATEMENT OF PROBLEM

A satellite can be defined as an artificial body or object placed

in orbit around the earth or another planet in order to collect

information, or for communication.

RESEARCH QUESTION

1. Is satellite communication relevant to national development?

2. What isthe usefulness of satellite communication in the

banking industry?

3. What are the people’s opinion concerning the impact?

4. What are the advantages, disadvantages, differences and capabilities of ku-band and C-band satellite services?

OBJECTIVES OF THE STUDY

The purpose of this seminar paper is to know why Satellite

communication is accepted generally and widely used worldwide.

Also to presents its contribution to national development and

also determine which of the frequencies is better by sampling the

openion of the subscribers.

METHODOLOGY

In this seminar paper the following statistical method are used

in gathering the information, transcription from records, random

sampling method and interview method are used in gathering the

data used in data analysis and presentation. The user of VSAT

satellite communication equipmentwere interviewed on the type of

VSAT equipment they are making use of. Some make use of C band

VSAT while some prefer ku band, and few are aware of ka band

which is the most recent VSAT equipment type. Below are the

responses from the interview.

Table 1: Number of subscribers and the type of VSAT they are

making use

Cities C band Ku band Ka band Total

Lagos 10 7 3 20

Ibadan 11 8 1 20

Osogbo 13 7 0 20

Ilorin 11 9 0 20

Benin 9 8 3 20

Abuja 9 9 2 20

 Grand Total 63 48 9 120

Chart 1: Number of subscribers and the type of VSATused

Lagos Ibadan Osogbo Ilorin Benin Abuja0

2

4

6

8

10

12

14

C bandKu bandKa band

Table 2:Percentage Number of Subscribers and the type of VSAT

used

Cities C band Ku band Ka band Total %

Lagos 50% 35% 15% 100%Ibadan 55% 40% 5% 100%Osogbo 65% 35% 0% 100%Ilorin 55% 45% 0% 100%Benin 45% 40% 15% 100%Abuja 45% 45% 10% 100%

Chart 2: Number of Subscribers and the type of VSAT used

Lagos Ibadan Osogbo Ilorin Benin Abuja0

10

20

30

40

50

60

70

C bandKu bandKa band

DISCUSSION OF RESULTFrom the analysis of data shown in table 2 above a total number

of 60 subscribers wereinterviewed in six urban cities in Nigeria

namely; Lagos, Ibadan, Osogbo, Ilorin, Benin and Abujato know

what type of VSAT satellite communications they use. The number

of people making use of C band, Ku band, and Ka band are shown in

table1. Table2 showsthe percentage responses. While chart 1 and

chart 2 diagrammatically represent the responses.

.

Prospects of the Satellite communication technology in Nigeria,

Africa and the rest of the world towards development

Satellite communication would impact national development ICT

development in thefollowing ways.

i. Boost the country’s knowledge economy drive. This involves

creatinghumans with knowledge, i.e. the development of highly

skilled workersthat can create products that will be competitive

in the global market.

ii. Facilitate access to education, through e-library and online

collaborationamong the tertiary institutions within and outside

the country.

iii. Facilitate the Central Bank of Nigeria’s pursuit of a

cashless economy.

iv. Boost the government’s e-government initiative, by reducing

the cost ofbandwidth for government ministries, departments and

agencies (MDAs),which according to Ahmed (2012) is costing the

Federal Governmentabout N75 billion yearly.

v. Boost the development of indigenous software applications,

thereby aidingNigeria’s quest for a knowledge driven economy.

vi. Facilitate the nation’s telecommunications services delivery

bycomplementing the existing terrestrial infrastructures

vii. Facilitate cheaper access to the Internet, and by so doing

help bridge thedigital divide between the urban and the

predominantly rural communities,thus help to bring the government

nearer to the grassroots

viii. Promote ICT usage and ICT skills by providing affordable

high speedbroadband Internet and telecommunications services for

videoconferencing, voice over internet protocol (Voip); Tele-

presence such asDistance Learning, tele-medicine, tele-health, e-

commerce, e-agric, ehealth,e-learning, etc

ix. Help in the development of indigenous competence in the

managementand operations of satellite and related technologies in

the country. In thisregard, Ahmed (2011) stated that NigComSat

Ltd has over 200 trained andequipped indigenous engineers in

their employment for the spacecrafttracking and control,

technology customization and domestication.

x. Boost Television and Cable television broadcasts penetration

into all areasof the country, especially the inaccessible remote

areas.

Advantages of communications satellites

i. Available everywhere - Satellite communication is

availableeverywhere where it has a footprint. This implies

uniform services for alllocations where there is satellite

footprint and a clear sky view.

ii. It is simpler and cheaper, since there is only one point of

contact for alllocations, unlike a situation where there are

multiple local serviceproviders.

iii. Security – Satellite systems/networks are more secure and

enhanceprivacy of individuals, government, military,

organizations and businessesthan the alternative terrestrial

technologies. Data are usually encryptedusing the most advanced

algorithm during transmission to ensure that it isnot

compromised.

iv. Reliability – Satellite networks / systems have fewer

potential points offailure than the terrestrial networks. It has

some built-in redundancy atevery level as backup in case of

failure or problem. It can assure 95%availability to all sites

regardless of location.

v. Multicast content distribution – Satellite communication,

through the

use of VSAT is very ideal for the distribution of bandwidth-

intensive

information like video and audio to a large number of remote

locations

simultaneously.

vi. Satellite networks are less costly to deploy, install,

maintain and operate,

because it does not require cabling (like copper wires, fibre

optics cable).

VSATs can penetrate areas not accessible to cables.

Disadvantages

i. Satellite receptions are badly affected by bad weather since

there must be

clear sky view for reception to take place.

ii. Obstructions such as tall buildings can cause problem for

satellite

operation because satellite systems follow line-of-sight to

communicate

iii. There can be problem of monopoly, especially in the case of

NigComSat-

1R, since it is only one company that will be licensed to deploy

theinfrastructure to the clients across the country.

Challenges of Satellite Communications

i. Inconsistency in government policy - The biggest

challengeNigComSat Ltd will face, especially in Nigeria is

inconsistency ingovernment policies, which is capable of ruining

or boosting the companyin its delivery of satellite services to

the world.

ii. Power supply - Another major concern is inadequate supply of

electricityto the expected users, especially in Nigeria, where it

is not possible to havea steady supply of the resource for

consecutive two days. Most ruraldwellers in Nigeria have no

access to electricity at all.

iii. Security of infrastructures – Because of the current spate

of insecurity inthe country, NigComSat will go an extra mile in

providing adequatesecurity for their systems, and this will

eventually translate into higheroverhead operating costs.

iv. Co-operation of other stakeholders in the telecom industry –

Cooperationof other major players and stakeholders in the telecom

industryis very essential for the success of satellite services

v. Backup satellite – To forestall the chances of failure of the

satellite andavert its adverse grave consequences to the users of

the satellite, there isthe need to have backup satellites in the

nearest future.

vi. Public awareness & deployment of services – It is not always

easy forpeople to change from the old system of doing things to a

new one,especially in an area where he/she is not knowledgeable

enough.

Therefore, for the efficient utilization of Satellite

communications, there isneed for adequate public awareness. This

will go along with immediatedeployment of the infrastructure [7]

ConclusionGenerally, Sattelite communication systems operate in the Ku-

band, C-band and, most recently, Ka-band frequencies. As a rule

of thumb C-band (which suffers less from rain attenuation, but

requires larger antennas) is used in Asia, Africa and Latin

America whilst Ku-band (which can use smaller antennas, but

suffers from rain fade in a monsoon-like downpour) is used in

Europe and North America. Typically, interactive Ku and Ka-band

antenna sizes range from 75 centimetres to 1.8 metres and C-band

from 1.8 metres to 2.4 metres. One way systems can use antennas

as small as 45 centimetres.

It can be concluded therefore that C-band satellite service is

better suited for subscribers with large bandwidth requirements.

This is because it easily supports Enterprise levelconnectivity

featuring dedicated CIR bandwidth with an SLA and guaranteed

uptime included. Also, C-band is very dependable and less

susceptible to weather related service outages.

Conversely, Ku and kaband operates with a smaller satellite dish

antenna and less expensive equipment which makes it more

attractive for small networks seeking shared bandwidth service

solutions. It should be noted that, in my opinion, one service is

not necessarily better than the other. Actually, both frequency

bands deliver a high quality satellite signal that will

adequately satisfy any communications needs.

If you have a choice, it should be a decision of what frequency

band will be most appropriate for your service location and

needs. Essentially, each frequency excels in delivering optimum

operations for different service situations. For service in the

Middle East, the ku band is very dependable and efficient. It'smore appealing, especially for military personnel deployed throughout the

Middle East. This is because the ku satellite system is less expensive, and

the smaller dish size makes it less conspicuous and easier to transport if

your deployment location changes.

REFERENCES[1] Brightman, R. W. et al (1996) Using Computers in an Information Age. New York. Delmar Publications.

[2] Gbenga O. (2011) NigComSat-1R arrives orbital home. The Nation Newspaper, December 30, 2011.

[3] O’Brien, James A. (1997) Introduction to Information Systems (8 edition). New York, Irwin/McGraw-Hill[4] Osuagwu P.(2011). How NigComSat-1R will impact Nigerian economy.Vanguard Newspaper, Dec 14, 2011.

[5] Osuagwu P and Akinhoade L (2011) Nigeria returns to space with NigComSat-1R launch. Vanguard Newspaper, Dec 20, 2011.

[6] Atili A (2012) NigComSat-1R connect 60% MDAs. The Nation Newspaper,January 3, 2012

[7] Nwajiobi, Emmanuel Nnamdi (2012), The Nigerin Communications

Satellite (NIGCOMSAT-1R): Relevance and Impact on Information and

Communication Technology (ICT) development in Nigeria and Africa.

Journal of Research in Pure and Applied Sciences Vol 1 No 1 June 2012

[8] http://www.comsys.co.uk/wvr_info.htm

[9] http://www.satelliteinsight.com/c-band-satellite.html

[10] http://www.satelliteinsight.com/satellite-dsl-blog.htm7

[11] http://www.linksystems-uk.com/index.php/vsat-technology-

features

[12] http://en.wikipedia.org/wiki/Ka_band