GSM network planning

7/28/2019 GSM network planning

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RF SurveyP o in t s To be Con s ide red i n Su rvey Most populated areas.

Business Centers.

Developing areas.

W ha t To P l an No. of Sectors required. Type of Antenna & Height.

Capacity Required.


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Planning a Fill In Site.


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After Integration of the Site.


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Frequency Planning.

Frequency Reuse Concept.

Use of same frequency at differentplaces.

Co Channel Interference.

Adjacent Channel Interference.

Use of Map Info.


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Frequency Planning Using

MAP INFO.


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BSIC Planning.

BSIC = NCC + BCC.Base station Identity Code.

NCC.(NETWORK Color Code).

BCC.(Base Station Color Code).Values Range From 0..7.


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Importance of BSIC.

Identify the BTS.

Used to reduce DROP Calls during Co ChannelInterference.

Mobile cant understand co channel & identifyno difference between same frequency signal

coming from two sites & so DROP Call. BSICis the parameter that helps the mobile toidentify the different BTS.


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Drive Test.On Field Optimization

Include four tests

Verification

Drive in dedicated mode

Foot print

Hand over test


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Verification

MOC Test

MTC Test SMS Test

GPRS Test

Drive in dedicated mode

Checking signal strength in the entirecoverage area.

Checking C/I, C/A.


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Foot print

Checking the shooting distance of each

sector. Results of footprints are used in predicting

interference in neighboring cell due toovershoot or similar problems.

Hand over test

Intra cell hand over

Inter cell hand over


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Current Channel

Definitions:

1. Time: It is system time of computer.

2. Cell name: It displays the name ofthe sector which is serving according

to the cellfile that is loaded in TEMS.3. CGI : It stands for the Cell Global

Identity which is unique for everysector of the site. It consists ofMCC,MNC,LAC,CI.

MCC: Mobile Country Code 0 999(e.g. 404 in India), MNC: Mobile

Network Code 0 99 (e.g. 98 forAirtel in Gujarat) LAC : LocationArea Code 0 -65535 (e.g. 5101 inGujarat) CI: Cell Identity 0 65535(e.g. 11001)


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Current Channel

Cell GPRS Support: Tells sector is

having GPRS or not. Values are Yes orNo .

Band : It tells in which Freq. Band mobile

is operating e.g. GSM 900/ 1800.

BCCH ARFCN: It tells by which BCCH

is the mobile station getting served.

TCH ARFCN: On which Traffic Freq.call is going on.

BSIC (Base Station Identity Code) : It is

combination of Network Color Code

(NCC) (0 7) & Base Station Color Code

(BCC) (0 7). e.g. 62. It is decoded by

mobile on every Sync. Channel Message.

Mode: It is shows in which state is mobile

operating, Idle, Dedicated & Packet.

Time slot: On which time slot of current

TCH call is going on. Viz. time slot no. of

TRX.


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Current Channel

Channel Type: Type of channel mobile isgetting now. Like BCCH / SDCCH/8 +SACCH/C8 or CBCH / TCH/F+FACCH/F +SACCH/F.

Channel Mode : Shows mode of codinglike Speech Full Rate of Half Rate.

Speech Codec: It shows FR for Full Rate,HR for Half Rate & EFR for Enhanced

Full Rate. Ciphering Algorithm : It shows ciphering

algorithm used by the system to protectdata for privacy. E.g. Cipher by A5/2.

Sub Channel Number: It is displayed ata time when mobile is on dedicated modeat time of call setup when it is getting

SDCCH at that time it shows whichSDCCH it is getting out of 8 available.E.g. 2.


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Current Channel

Hopping Channel : It shows that current

sector is having hopping feature or not.Values are Yes or No.

Hopping Frequencies : It displays no. of

freq. on which mobile is allowed to hop.

viz. MA List for hopping of that sector.

Mobile Allocation Index Offset (MAIO):

It is the number which tells from which

freq. from given MA list for sector

hopping has to be started. E.g. 0 means

sector will start from first freq. to hop.

Hopping Sequence Number (HSN) :

Indicates sequence in which frequencies

are allowed to hop from the MA List. 0-

63. 0 for Cyclic Hopping, 1 63 randomhopping sequences.


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Radio Parameters

RxLev : Receiving level in terms of dBmthat mobile is receiving from the site.

Range of -30 dBm to -110dBm. RxQual : Quality of voice which is

measured on basis of BER. Range ofRxQual 0 -7.

FER : Frame Erasure Rate it representsthe percentage of frames being droppeddue to high number of non-corrected biterrors in the frame. It is indication of voicequality in network.

BER Actual : Ratio of the number of biterrors to the total number of bitstransmitted in a given time interval. BERis a measure for the voice quality innetwork.. Depending on BER RxQual ismeasured. E,g, BER 0 to 0.2 %corresponds to RxQual 0. Max. BERcountable and useful is up to 12.8 % whichcorresponds to RxQual of max. 7.


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Radio Parameters

SQI : SQI is a more sophisticated measure

which is dedicated to reflecting the qualityof the speech (as opposed to radio

environment conditions). This means that

when optimizing the speech quality in

your network, SQI is the best criterion to

use. SQI is updated at 0.5 s intervals. It is

computed on basis of BER and FER. For

EFR 30, FR 21 & HR 17 arerespectively ideal values.

C/I : The carrier-over-interference ratio is

the ratio between the signal strength of the

current serving cell and the signal strength

of undesired (interfering) signal

components. It should be atleast > 9 . MS Power Control Level : Displays

range of power control from 0 to 8

depending upon network design. E.g. 0

means no power control and 1 means

level that is defined by operator viz. 2

dBm less acc. To airtel.


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Radio Parameters

DTX :Discontinuous transmission (DTX)

is a mechanism allowing the radiotransmitter to be switched off during

speech pauses. This feature reduces the

power consumption of the transmitter,

which is important for MSs, and decreases

the overall interference level on the radio

channels affecting the capacity of the

network..

TA : Value that the base station calculates

from access bursts and sends to the mobile

station (MS) enabling the MS to advance

the timing of its transmissions to the BS so

as to compensate for propagation delay.

Value of 0 means MS in radius of 550mt.From BS.


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Radio Parameters

RL Timeout Counter (Cur) : This

parameter define the maximum value ofthe radio link counter expressed in

SACCH blocks. Range of 4 64 in step

size of 4. it shows current value of RLT.

Decrease by 1 but increase by 2. When it

reaches zero it results in normal DROP

Call.

RL Timeout Counter (MAX) : This

parameter define the maximum value of

the radio link counter expressed in

SACCH blocks. Range of 4 64 in step

size of 4. it shows current value of RLT.

Normally 16, 20, 24.

MS Behavior Modified : This windowshows current settings for the mobile

station, for instance whether handover is

disabled or multiband reporting enabled.


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Serving + Neighbor

Cell Name :Name that describes the neighboring cell as per the cellfile.

ARFCN : Channel number mobile receives as neighbor.

BSIC : BSIC of the neighboring cell.

RxLev : Receiving Level in dBm of neighboring cell.

C1 & C2 : These are the cell path loss criterion and cell reselection criteria. Valid during idle modeof mobile station.

C31 & C32 : GPRS signal strength threshold criterion C31 and GPRS cell ranking criterion C32.Valid both in packet idle and packet dedicated mode.


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Other Useful Parameters.

Adjacent ChannelSignal Strength.

Carrier to InterferenceRatio.

Value of C/I range from -5..25. It should be more than 9.


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C/I Values

C/I Values Shown using line chart.


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Rx. Level, SQI, FER.


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Example


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Drive in Dedicated Mode.


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Foot Print.


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Signal Quality.


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In Building Solution.

NECESSITIES:

Low in building coverage.

More No. of users in a Business

Center having less coverage.


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Planning an IBS.

Check for the Coverage in the building.

Make Floor plan.

Plan different type of antennas according toneed.

Prepare Routing Diagram.

Prepare Link Budget. Accordingly plan Ultra or Metro Site.

After Integration do Walk Test.


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Floor Plan.


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Cable Routing.

This Diagram showsthe length of the cables& Splitter or Couplerthat is used forPreparing Link Budget.


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Link Budget.


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Walk Test.


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THANK YOU

By- Toshniwal Enterprises Controls Pvt.Ltd.

GSM network planning

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