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HI HASHEM,
THIS IS SRIKANTH .
THANKS FOR GIVING THE WEB SITES THOSE ARE VERY GOOD.
KEEP IN CONTACT.
URS,
SRIKANTHhi srikanth
ur wellcome
i am here and always in contact ,
BR
hashem@korektel.comHi ALL
iam having SD_Drop and low CSSR on the 1800 sectors and 900 sectors are okey,what could be the problem.Nachi,
If you are using dualband cells (1 BCCH for both 900 cells and 1800 cells), you shouldn’t have SDCCH set on the 1800 cells.
Mobile located far away, without 1800 coverage, might set their call on the BCCH and then be directed towards the 1800 SDCCH to finish the call setup. The RxLev drops, therefore creating SDCCH drop…
Cheers,
Pixanyone who can give me the parameter values of drive test in gsm, and what r the things to note down and find out in mw survey and rf survey.
thanksajay,
drive tests parameters : define one typical route on a map that you’ll follow for each drive test, drive during busy hour and during night hour (to compare).
ajay,
drive tests : drive slow in cities, and at limit on intercities roadsMW survey : antenna support (height, type), coordinates, equipment location, pictures, sketch, and line of sight with other equipments.
RF survey : antenna support, antenna type, height, coordinates, azimuth, tilt, pictures of the site + pictures of landscape facing each azimuth, sketch of ground, where to put the BTS, cable length, building or area owner, details of contact person.
It is important to document all your “feelings” and rank several possibilities (= candidates) for one site. You have to be precise and update your files and photos everyday on your computer, or you’ll be lost at the end of the site surveys.
Can anybody explain me the C2 criteria in cell reselection.
Hi Nishant,
Actually in idle mode, the mobile always prefers to remain with or move to the best serving cell. The best cell is decided on the basis of uplink and downlink path balance in the cells. This balance is calculated by GSM defined C1 calculations. C1 calculations force the mobile to move to the strongest cell. In certain cases, such as macro-micro cell architecture, optimisation may require that in certain areas the mobile not remain in the best cell, but instead remain in a cell depending on traffic loading. C2 parameters provide the option of adding fixed positive or negative offsets to the C1 calculation in each cell. So, although C1 might be better for a neighbour cell, the application of C2 parameters could delay reselection. C2 parameters also allow the mobile to apply temporary offsets for a period known as penalty time, which helps reduce Ping-Pong effects. With the help of carefully done drive test these parameters like offset or penalty time for handovers can also be checked and verified.
BR//
Yogesh_rfHi PIX
im not currently using the multiband cells,the 1800 has its own BCCH and SDCCH,so does the 900,in my case what do i have to do to counter the same.I have noticed that the is a corresponding low CSSR and the SD traffic has increased on 900.
rgds
NachiHI ALL
I WANT TO KNOW ABOUT LARGE VARIATION IN Rx LEVEL IN G.S.M NETWORK.nachi,
your explanations are not very clear for me.. as far as i understand, you have low CSSR (high SDCCH drop) in the DCS1800 band and a longer SDCCH duration in the GSM900 band.
this is occuring on all cells ?
i would need to know your cell planning topology, your parameters and other KPI.. I need to know about the handovers 900/1800, call setup, layer definitions, frequency planning… basically, you need to offer me a trip to your country so I can have a good look to it 🙂 i sincerely doubt I can solve this over the internet… maybe someone else can.
nc modi,
large variations in a very short time can be due to
… DL power control + baseband frequency hopping : “bcch frame” rxlev will be high, whereas other frames will be low level.
… a faulty TRX or a faulty ANC (amplifier)
Now, you have to tell us what do you consider as a “large” variation (how many dB ?) and in what kind of time intervals they occur. Does the MS ping-pong between different cells ?
Can anyone explain how a number of sites are imported into TEMS cell planning?
sir. even if the sub.is in coverage area,sometimes we r geting “out of coverage area”
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