129281009 1 OEP100310 LTE Radio Network Coverage Dimensioning ISUEE 1 03

7/30/2019 129281009 1 OEP100310 LTE Radio Network Coverage Dimensioning ISUEE 1 03

1/58

LTE Radio Network Coverage Dimensioning

Confidential Information of Huawei. No Spreading Without Permission


2/58




3/58




4/58

LTE radio network planning can be divided into three phases. They are shown in above

figure, and consist of dimensioning, nominal planning and cell planning.

According to the above figure, the output result of radio network dimensioning stage

serves as the input condition of the nominal planning, and the nominal planning is based

on the network dimensioning and also checks the network dimensioning result. The site

quantity can be adjusted according to the nominal planning result in order to obtain the

reasonable sites. If the existing sites are considered in the selection of theoretical sites

during the nominal planning, the nominal planning result will be more practical, thus

facilitating the cell planning.




5/58

Radio Network Dimensioning is a simplified analysis for radio network

Dimensioning provides the first and most rapid evaluation of the network element numberas well as the associated capacity of those elements. The target of dimensioning phase is

to estimate the required site density and site configurations for the area of interest.

Dimensioning activities include radio link budget and coverage analysis, capacity evaluation

and final estimation of the amount of eNodeB hardware, cell average throughput and cell

edge throughput.

Objective:

To obtain the network scale ( approximate eNodeB number and configuration)

Method: Select a proper propagation model, traffic model and subscriber distribution, and

then estimate the eNodeB number, coverage radius, cell throughput, cell edge

throughput and so on.




6/58

Wireless network dimensioning intends to obtain the approximate EUTRAN scale. Based on

the network dimensioning, geography and traffic distribution, the network is pre-planned

in detail by using planning software and digital map.

Based on the network dimensioning and site information, the initially selected LTE site is

imported into the planning software, and coverage is estimated by parameters setting.

Then an analysis is made to check whether the coverage of the system meet the

requirements. If necessary, the height and tilt of the antenna and the eNodeB quantity are

adjusted to optimize the coverage. And then the system capacity is analyzed to check

whether it meets the requirement.

Plan implementation parameters, such as antenna type / azimuth / tilt / altitude / feeder

type / length

Plan cell parameters, such as tracking area planning, PCI planning, Neighbor relation

planning, PRACH configuration planning




7/58

We should consider other factors when we select the backup sites

Commercial factor: rent Radio propagation factor: situation / height / surrounding /

Implementation factor: space / antenna installation / transmission / power supply




8/58




9/58


10/58




11/58

Generally, LTE has the same dimensioning procedure as the other wireless system

In the coverage dimensioning, the link is estimated according to elements such as plannedarea, network capacity, and equipment performance in order to obtain the allowed

maximum path loss. The maximum cell radius is obtained according to the radio

propagation model and allowed maximum path loss. And then the site coverage area is

calculated. Finally, the site quantity is calculated. Of course, the site quality is only for the

ideal cell status, and some additional sites will be needed in actual terrain environment.




12/58




13/58

The main goal for coverage dimensioning is the estimation of the site coverage area, i.e.

identify the number of sites for a given area. This is achieved using a link budget

calculation which provides an estimate on the maximum allowed PL (Path Loss) in the

downlink and uplink. Once the maximum Path Loss is identified it can be used to calculate

cell range, cell area and site area.




14/58




15/58




16/58

1.03bug




17/58

EIRP, Equivalent Isotropic Radiated Power




18/58




19/58




20/58

The type of area will affect the pass loss during the link budget, including

Channel mode Indoor penetration loss

Standard deviation of shadow fading margin

Path loss factor

Morphologies determines the propagation model formula using in cell radius calculation,

as well as other parameters such as eNodeB antenna height and penetration loss

Channel model has effect on the demodulation threshold and lead to difference cell radius

ETU: Extended Typical Urban model

EVA: Extended Vehicular A model




21/58




22/58

EIRP, Equivalent Isotropic Radiated Power




23/58

In LTE system, OFDMA is used for resource allocation. For different BW, receiver sensitivity

is different, so during the link budget, we should take the single RE as a uniform standard

for calculation




24/58




25/58




26/58




27/58




28/58




29/58




30/58

The ratio of useful signal to noise, is the key parameter in Rx sensitivity calculation and the

representation of equipment performances of features.

MCS = code bits * code rate




31/58




32/58




33/58

Service rate is the transmission rate after Layer2 process but without

adding CRC

CRC=24

DL:

Every two RBs(1ms sub frame) include RE=1214168.If

the control channel use 3 symbols, RE=312.If RS use 1

symbol, RE=112

UL:

Every two RBs(1ms sub frame) include RE=1214168.If

the control channel use 2 symbols, RE=212.

MCS = code bits * code rate

From service rate and protocol 36213 table 7.1.7.2.1-1,the different RB

number and ITBS will be found. From protocol 36213 table 7.1.7.1-1, the IMCS

will be found.




34/58


35/58




36/58




37/58

The IM is added to the link budget to compensate for the loading of the cell, i.e. the

higher loading allowed, the larger is the interference margin specified.




38/58



Sometimes during the planning, coverage probability also has to be considered.

And for high coverage probability, high shadow fading margin reserved. Normally,

there are two types coverage probabilities: area coverage probability and edge

coverage probability.

According to the standard deviation of the shadow fading and the requirements

for the border coverage probability (determined by the operator), we can calculate

the edge coverage probability by formula.


39/58




40/58




41/58

According to the standard deviation of the shadow fading and the requirements for the

border coverage probability (determined by the operator), we can calculate the shadow

fading margin by:

Mf (dB value)= NORMSINV (Border coverage probability) x r where

NORMSINV () is the inverse function of the standard normal distribution

accumulation function. The 75% border coverage probability is corresponding to

0.68.




42/58




43/58

SFBC: Space Frequency Block Coding

MCW: Multiple Code Word




44/58




45/58




46/58




47/58




48/58




49/58


50/58




51/58




52/58




53/58




54/58




55/58




56/58




57/58




58/58


Documents

129281009 1 OEP100310 LTE Radio Network Coverage Dimensioning ISUEE 1 03