2G Main Data

7/25/2019 2G Main Data

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2G DATA

Parameters regarding in windows like:a) Current Channelb) Radio parametersc) Serving + Neighbors

Current Channel:

Time: It is system time of computer.

Cell name: It displays the name of the sector which isserving according to the cell le that is loaded in TEM.

CGIIt stands for the Cell !lo"al Identity which is uni#uefor every ector of the site. It consists of MCC$ M%C$ &'C$and CI.MCC: Mo"ile Country Code ( ) *** +e.g. ,(, in India-$M%C: Mo"ile %etwork Code ( ) ** +e.g. * for 'irtel in


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!u/arat- &'C: &ocation 'rea Code ( 012232 +e.g. 24(4 in!u/arat- CI: Cell Identity ( ) 12232 +e.g. 44((4-.

Cell G!RS SupportTells sector is having !P5 or not. 6alues

are 7es or %o."andIt tells in which 8re#. 9and mo"ile is operating e.g. !M*(( 4((.

"CC# AR$CN: It tells "y which 9CC; is the mo"ile station gettingserved. +


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Channel %ode:hows mode of coding like peech 8ull5ate of ;alf 5ate.

Speech Codec It shows 85 for 8ull 5ate$ ;5 for ;alf

5ate A E85 for Enhanced 8ull 5ate.'M5: 'daptive Multi 5ate

Ciphering Algorithm:It shows ciphering algorithm used"y the system to protect data for privacy. E.g. Cipher "y'2B.Sub Channel Number: It is displayed at a time whenmo"ile is on dedicated mode at time of call setup when it

is getting =CC; at that time it shows which =CC; it isgetting out of availa"le. E.g.B.

+


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If ;% is Gero$ the fre#uency hopping se#uence is cyclic$i.e. without changes.

If ;% is greater than Gero$ then fre#uencies vary pseudo0randomly;% is used to avoid correlation "etween the closelyrelated cells.

5adio Parameters

R( ,ev5eceiving level in terms of d9m that mo"ile isreceiving from the site. 5ange of 03( d9m to 044(d9m.EHCE&&E%T: 03( to 01(6E57 !


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'CCEPTE=: 0( to 0*(9'=: 0*( to 044(R( -ual:uality of voice which is measured on "asis of9E5. 5ange of 5F ual ( 0@.

EHCE&&E%T: ( to B!


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4 1.6% < BER < 3.2%

5 3.2% < BER < 6.4%

6 6.4% < BER < 12.8%

7 12.8% < BER

S-I peech #uality indeF is a parameter to rate thevoice #uality on a particular call.I is updated at (.2 sintervals. It is computed on "asis of 9E5 and 8E5. 8or E853($ 85 ) B4 A ;5 ) 4@ are respectively ideal values.!


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The timing advance ensures the "ursts arrive at theirdestination in the appropriate time slot. The mo"iletransmits a random access "urst in the uplink$ and the9T will make measurements$ sending an ad/ustment on

the downlink. Timing advance is measured in "its and can"e ad/usted up to 13 "its$ with each "it lasting 3.1* ms.

Radio ,in5 Timeout R,T) Counter: It is a "idirectionalcounter and is set as per parameter when call started indownlink in mo"ile and uplink at T5H in the particulartimeslot.5&T is applied only when call is on TC;$ =uringcall in TC;$ in downlink network send system info 2 and 1

which is carrying very important information a"outneigh"or$ cell$ power control related in every ,(ms+ 4complete 'CC; 5adio "lock-$If Mo"ile cannot a"le todecode 4 'CC; "lock then 5&T will reduces "y 4 and if itdecode ''C; 9lock then it will increase "y B and if it"ecome ( means call is drop due to some down linkpro"lem.

L This parameter indicate how much time callmaintained when radio environments is "ed.L If 5&T value is high then call is sustain longer time.L ;ighway and in "uilding cells have higher value of5&T parameter and it is give "etter improvement of calldrops.

%S "ehavior %odi6edThis window shows the current

setting for a mo"ile station$ for instance whetherhandover is disa"led or multi "and reporting ena"led.

erving D %eigh"or "y "and


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Cell Name%ame that descri"es the neigh"oring cell asper the cell le.

AR$CN:Channel num"er mo"ile receives as neigh"or.

"SIC:9IC of the neigh"oring cell.

R( ,ev:5eceiving &evel in d9m of neigh"oring cell.

C4 7 C2:These are the cell path loss criterion and cellreselection criteria. 6alid during idle mode of mo"ilestation.C 4: Cell election uantityCB: Cell 5eselection uantity.

C84 7 C82:C34: !P5 signal strength threshold criterion.C3B: !P5 cell ranking criterion.6alid "oth in packet idle and packet dedicated mode.

C9/RAG/ ISS./S


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R/ASN $ CA,, DR!

a. 9ad uality & or =& or 9oth.". 9ad #uality due to interference.

c. &ow ignal trength & or =& or 9oth.d. Timing 'dvancement limit reached.e. 5adio link Timeout +5&T- Counter reached to its

maFimum value.f. TC; activation failures during call.g. Missing neigh"ors +handover not dened-.h.=elayed ;andover due to lack of capacity in

target cell.

i. If the 'CC; frame is not received$ then it isconsidered to "e dropped call./. 8aulty T5H.k. Transmission pro"lem.l. ;ardware Pro"lem +9T related-.

Calls can drop in the network due to #uality degradation$which may "e due to many factors such as capacitylimitations$ interference unfavora"le propagation

conditions: bloc5ing: etc;$ault& DTR.%oticing "ad 5F0&evels for specic TC;s in!M hopping channels window while under site$ this may"e due to ca"inet T5H0=T5 card hardware pro"lemwhich generates power for these TC;s.

NT/t bad because o? cross ?eeder problemthat these TC#s po1er are not being transmitted in


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another region 1ith good levels be?ore decidingthat it is DTR. card hard1are problem;

R/ASN $ #AND9/R $AI,.R/

;< failure means that M fails to reach the target cell dueto "ad #uality or "ad coverage or congestion$ so it returnto the old cell

a. uplink interference". downlink interferencec. neigh"ors not well denedd. %on ymmetrical +


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4=Congestion In B! there are B types of congestion

SDCC# congestion problem Ono =s availa"le for you

to perform call0setup procedureQ and it appears on TEMin &ayer 3 messages as ONo Immediate AssignmentQmessage.

TC# congestion problem Ono Tra?c channels availa"leto perform your call0setup procedureQ and it appears on

TEM in &ayer 3 messages as ONo Trac ChannelAssignmentQ message.

NT/ It>s normal that vershooting site to &ouma& su*ers congestion as it 1ill be carr&ing tracand serving users in its region and other users in&our ?ar a1a& serving region;

2="ad radio conditions7ou then suRer from "ad 5F&evel or "ad 5F uality so you cant communicate with

your serving cell or decode any of its =& messages

09ad 5F &evels can "e a result of "ad B! coverage wherethere is no dominant server eFists in the area.

09ad 5F uality can "e caused "y "ad coverage O"adlevels results "ad #ualityQ or due to a high level ofinterference Op0link or =own0link interferenceQ on eitheryour M or your serving cell and it appears on TEM in&ayer 3 messages as BNo ServiceQ message.

".T ho1 to di*erentiate that bad 'ualit& is due tobad coverage R( levels or due to inter?erence


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09ad uality in case of "ad levels is normal as "ad levelswill normally causes "ad #uality hile09ad uality in case of good levels$ so for sure there is

interference.

8=#ard1are problem in %/ handsetometimes yourtest mo"ile suRers temporary sudden errors due toeFcessive usage$ so it reports "locked calls with noapparent reasonQ and it may appears on TEM in &ayer 3messages as ONo Alert or ConnectQ message.

INT/R$/R/NC/hen noticing that #uality in B! GS% Radio!arameters window OR( -ualQ and value of C0I in GS%#opping Channels window are "ad for specic '58C%swhile levels of B! coverage for the same '58C%s aregood$ where

There eFist B types of interference:4. p0link interference.2;=ownlink interference.

4=.p=lin5 inter?erence+Mo"ile to 9T-

7our serving cell will not "e a"le to decode any of yourup0link messages if your M suRers any up0linkinterference.p0link interference is interference on your M mo"ilehandset$ causes "ad #uality in up0link "etween your Mand the network$ where an eFternal system transmits


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power on a specic fre#uency '58C% which is the sameas the fre#uency you are using to communicate with yourserving cell. o$ any message or information you aretransmitting on this '58C% may suRer high amount of

errors due to interference causing high 9E5 O9it Error5ateQ so #uality turned "ad "y time.

2=Do1n=lin5 inter?erence+9T to Mo"ile-7our mo"ile will not "e a"le to decode any of the networkdown0link messages if there is any down0link Interferenceon the serving 9T.

There are B imp. Types for the down0link interference:Co=Channel Inter?erence7ou nd a "ad #uality and"ad CI pro"lems for a specic '58C% in good 5F levels.


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hen we get the signal from an away site that not closeto the current area of drive test$ whether this site was

serving you or /ust appears as a neigh"or with good 5Flevels to you.sually we get "ad OR( -ualQ due to down0linkinterference from neigh"oring cells with Co. or 'd/acentchannel 9CC; and large value for TA OTime AdvanceQalso it may causes call drop "y the time as you will not "ea"le to perform handover "ecause all the neigh"oringsites to you will "e missing neigh"ors for it Onot in yourserving site 9' listQ$ you will remain on serving site untilcall drops due to "ad radio conditions. It may also causeOcongestionQ pro"lem under this overshooting site as itis now serving away from its supposed coverage regionso the site near0"y users may found no resources to useD levels under site may "e "ad causing coveragepro"lems specially indoor.

NT/ An& sites near 1ater ma& overshoots due to

the ducting phenomena in 1ater that it couldtrans?ers signal ?or a large distances;

"loc5ing0ReEectionsCauses temporary "ad levels pro"lem


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hen 5F levels from your serving site suddenly drops tothe 0*(s04((s d"m which is very "ad Ohile it was verygoodQ in the 01(s during =T$ while you are near to siteand its levels to you was supposed to "e very good "ut it

suddenly turned "ad for a while then while moving levelsturned very good again OTemporary "ad levelsQ.

In reality eld you nd a "ody O"uilding0metal0trees0mountain or hill0etcSSQ which eFisted in the "ad levelsregion "etween you and serving site$ this o"stacle:0hether "locks &


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4= #igh SDCC# congestion causing bad @!I>s in C"RCall "loc5 Rate) due to high utiliFation on SDchannels;

2= Temporar& hard1are problem;

#andover !ing !ongRepeated)May causes call drop pro"lemIn very small arearoute also in a very small time period

you perform many #uickly handovers among B or morecells all are with high levels "ut none of them is highenough to "e the only dominant serving cell in the area.hile testing$ you are performing many handovers"etween your serving cell and neigh"oring cells all aretransmitting power in the area with very good levels.

1. Lack of dominance

2. Poor quality (due to poor frequency, HSN/MA! plan etc"

3. Poor parameter #alue in $%% (&uc' a& ron) 'ando#er

'y&tere&i& #alue or penalty timer after emer)ency H!"

9SR=#ard1areproblem

Causes bad levels or even gaps under site5ight under a site on TEM map or very near to it "ut the5F levels from it is very "ad$ so coverage under the sitewill "e "ad that it may causes calls to "e dropped rightunder serving site due to "ad levels.


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65 may "e due to a pro"lem in feeders$ /umpers orconnectors connecting the ca"inet to sector antenna alsoit might "e an antenna or a =T50card hardware pro"leminside ca"inet.

NT/ 9SR B9oltage Standing ave RatioH issimpl& means that the ?ull /IR! that is generated?rom cabinets are not ?ull& reaching sector antennaso levels under site turned ver& bad;

/IR! /$$/CTI9/ ISRTR!IC RADIAT/D !/R' measure of the power in the main "eam of an antenna

relative to an isotropic radiator.

No or ,ate #andover,eads to call dropped due to bad radio conditionsIn window O!M erving D %eigh"orsQ $ you nd a "etterneigh"or in level which is "etter than your now0servingcell "ut no or late+takes a while and not #uickly- handoveroccurred to this neigh"or which leads to "ad radioconditions from your serving now cell "y the time andmight cause call dropped.%o or late handover can "e due to:

4. TC; congestion.B. Poor0wrong ;.< parameters.

4=TC# congestionThis "etter neigh"or in level "ack then it may wassuRering from TC; congestion$ so it has no TC; resources

left to "e assigned to new users$ so no ;.< occurred to ituntil call is dropped.2=!oor #; parametersImagine you were served "y Cell 4 with "ad levels due tolarge distance away from it$ you see cellB as neigh"or


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with "etter levels "ut no ;.< occurredUUU sually due tolarge value of #; margin bet1een 2 cells;

NT/ #; margin is a 2G cell parameter: this

parameter determines 1hen to leave &our servingcell 4 and per?orm #; to the better neighbor cell2: in another 1ords I should per?orm #; to theneighbor cell 2 1hen its level is better than cell 4b& ho1 man& d"s

In some cases li5e this one #; margin o? cell 4 islarge so ho1ever cell 2 level 1as better than cell 4

but no #; occurred to cell 2 as its level is notreached &et the margin threshold o? #; to cell 41hich causes the dela& in #; bet1een the 2 cells;

rong #andoverhen a handover procedure occurs from a "etter 5F0levelserving cell to a lowerworse 5F0level neigh"or cell Ooccurwhen ;.< target cell is lower in level than serving cellQwhich is wrong.


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Data lin5 ?ailureM connection with the mo"ile network is esta"lishedupon layers connection$ so in order for M to esta"lishconnection with the new target ;.< cell to completehandover process$ M should esta"lish a transmissionlayer B O=ata link layerQ with the new 9T. hen M failsto any reason to esta"lish layer B with new 9T$ ;.< failsand M returns to old serving 9T 5


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information type 20terQ for other "and 9CC;s to see alldened neigh"ors 9CC;s to your serving cell.erved "y cell 42238 9CC;: J while radio conditionswas getting "ad$ noticed B near0"y cells O9CC;s: K8$L2KQ

"ut there 9CC;s dont eFist in GS% Serving +Neighbor window$ they may "e missing neigh"ors.

To con6rm that$ we checked "oth S&s;In?o T&pe M andS&s;In?o T&pe M=ter in la&er 8 messages and "oth9CC;s were not dened to serving cell 9CC;.

Good R(=,evels in 4 direction ".T turned bad inopposite direction

hen performing =T for a route$ moving from Cell 4towards Cell B hile served "y Cell 4$ you notice normalgood 5F0&evels on TEM map 9T when moving"ackwards on same route from Cell B towards Cell 4 you

notice that 5F0 &evels turned "ad on TEM map.


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This pro"lem may occur due to 4 of B possi"le reasons:

4;Served b& DCS o? Cell 2;2;Dela& #; ?rom Cell 2 to Cell 4;

4=Served b& DCS o? Cell 27ou were served "y Cell B =C "and with "ad levels as=C has high serving priority over !M even if it wasserving with "ad levels and !M levels were "etter "ackthen.

4=Dela& #; ?rom Cell 2 to Cell 47ou performed late ;.< to Cell 4 may "e due to poor ;.

2G Main Data

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