CrossTalk

[justdream]

Dears,

what's crosstalk exactly? I think I've detected one in my network as I received a call from a friend then ince I answered I found my-self speaking with unkown guy...
in the other side, my friend was not hearing anything 'silent'

how to sort out this issue????

[sarojmishra05]

Hopefully ckh fr interference... Im nt very sure.

[zhanglw268]

There are serveral crosstalk scenarios which I know.

1. at least 2 pair E1s cross wired, i.e. One E1's TX connect to another pair's RX, so the E1s looks normally, but the data is physically crossed to different E1 pair, so cross talk
2. 2 GSM cells facing each other or near each other with same frequency and BSIC, you will see cross talk
3. MSC side's transimission handling fault, so cause the cross talk.

You can narrow down the problem by check whether the problem happens in several cells, or several sites, in one BSC/RNC or whole MSC area, then you can tackle it more wisely.

What technology(GSM/WCDMA) you used?

Regards

David

[Cesarus_m]

Cross talk happen mainly when:

1. E1s on A interface are mixed up
2. Or CIC definition on both BSC and MSC are wrongly defined.

Br,

Cesarus

[telwind]

MW link interference may cause the cross talk as i have faced

[sarojmishra05]

Thnks all for r valuable posts!!!

BR/ Saroj

[leelio]

in GSM; sometimes cross talk happens differently from silent calls.

->cross talk mostly caused by cic mismatch between MSC and BSS, a call is assigned wrong CIC; this can be cleared by reconciliation of CICs between MSC and BSS at which problem appear mostly.
cross talk can also caused by cross connection of XCDR links to MSC; one have to check phsically if connection match with database.

->silent calls can be caused by faulty GDP,DIU; or any h/w that supports xcdr/msc functionalities;as it may cause sleeping cells

[justdream]

friend, what's the meaning of CIC?
how to perform this test? do you have some documents about it?

please share and many thanks :hug:

[zhanglw268]

friend, what's the meaning of CIC?
how to perform this test? do you have some documents about it?

please share and many thanks :hug:

CIC - Circuit Identity Code

The Circuit Identity Code is used to identify the trunk circuit to be connected between BSC and MSC which people call it A-interface for the C7/SS7 in GSM network. It is not practical to do the CIC test in the live network except that the BSC/MSC is brand new at the very beginning. It is better to let the BSS database engineer to work with MSC engineer to check their database, then do some basic check on the E1s in the maintenance hours.

Hope this helps.

[plannerguy]

RF part -can check for BSICs

Regards'
Plannerguy

[pamungkas]

hi, is it possible that croostalk occur in UMTS technology? since the connection between RNC and MGW using optical and ATM.