- This topic has 15 replies, 1 voice, and was last updated 9 years, 7 months ago by pix.
27th February 2012 at 22:28 #67921pritam chatterjeeGuest
how to counter jammer issue(jammer installed at jail).bts is generating alarm like mean holding time,excessive tch interfence .their is call muting,call craking,droping also.
pchatterjee28th February 2012 at 09:56 #67922pixGuest
the jammer is designed to destroy your gsm signal, you can’t do anything. if you want to improve your kpi, focus your cell coverage to other areas than the jail. In other words, re-azimuth your antenna to other directions.
if you think the jamming device is creating problems outside the jail, then contact the jail IT and ask them to reduce the jammer power.28th February 2012 at 20:04 #67923paraHOGuest
Send an email to me for a discussion on how to handle your problem of jammer.29th February 2012 at 12:20 #67924pixGuest
why not here ?29th February 2012 at 14:58 #67925RexGuest
Yes, why not here. I’m interested to know how to handle that problem.
Rex2nd March 2012 at 19:51 #67926pritamGuest
dropped the mail
please check2nd March 2012 at 19:51 #67927paraHOGuest
Hi pix, Rex
Wanted more detail from pchatterjee before postng any reply. It is not clear country where jammer being used. Maybe only interference (may not mean jammer involved). If local government using jammer in jail what legal issues involved.
How many Erlang forum members have problems with jammers?31st May 2012 at 17:07 #67928RexGuest
We have jammer issue in a specific area. UL interference increased, we have a lot of samples in interference band 5. And what is interesting in this case, channels from 1 to 71 are interfered and from 72 and up are Ok (competitors frequencies). I didn’t hear about a jammer that can be tuned for specific range of frequencies. In that area there are some foreign offices, is it possible that metal detectors and various appliances can cause interference in UpLink for a specific range?
Rex31st May 2012 at 18:54 #67929pixGuest
i looked at how gsm jammer works (and jammers in general) : they pollute the DL signal, not the UL.
So if you see UL noise in your qos, it means it is probably another device. The best step now is to go around the area with your frequency scanner, measuring the UL band power. You will quickly localize the interferer.
Why is it localised in your band only ? I don’t know. How did you measure that ?
pix1st June 2012 at 03:27 #67930dinendranGuest
i do have an issue with excessive tch interference with nsn bts near the secretariat.
I have suspected jammer in that area. But i too have heard that jammer has influence in ul quality so that person near the jammer cant transmit without interference. More over jammer is easly designable for low freq ul than high freq dl signal
expect ur response on this as im novice in this
dinendran1st June 2012 at 12:24 #67931RexGuest
we’ve tested channel by channel and from 72 to 124 there was no interference. Another indication that tells that interference is in UL is when we make a call we can hear the other party but they can’t hear us.
Rex2nd June 2012 at 07:31 #67932paraHOGuest
pchatterjee sent email back early March. You going to send email showing google maps reference for your masts and where the jail located where jammer sited. You never reply.3rd June 2012 at 02:01 #67933LexGuest
Kindly check is there any repeater used in that area is malfunctioning.
Let us know which make BTS you are using.3rd June 2012 at 06:37 #67934pixGuest
i was saying that jammers seem to be designed to transmit extra-noise in the DL band.
A jammer would be seen in DL only, no in UL.
(as far as i have seen !!!)
UL interference can be seen by looking at indicators named “idle ts interference band” (approx.)
DL quality can be quickly seen by doing a drivetest.
Radio measurements collected by your optim tool shows the rx quality of your cell in each direction.
Pix3rd June 2012 at 17:47 #67935paraHOGuest
I agree with your identification re: DL interference. I set out a test for pchatterjee in my email and not seen any test results come back.
If the email I sent of previously used and successful solutions work for pchatterjee then I will post them for everyone, but I had no response.