- This topic is empty.
23rd July 2006 at 17:43 #39545BradlingtonGuest
Motorola 2G question:
We in the GSM engineering GSM field are required to calibrate the gclk’s annually.
I am under the impression that this is a waste of time as far as I understand how GCLK’s work , the longer one leaves them the more stable they should become.
I would like to hear from anyone who knows these GCLK’s very well and have any statistical data to back the comments.
We have stable E1 links and phase lock to the incomming E1 on the primary link port.
Brad23rd July 2006 at 19:21 #39546Iftikhar AhmadGuest
Please ask me your questions in details about CDMA or GSM then I will answer you. But if you want total details of CDMA then I will recommend you the website of qalqam.25th July 2006 at 09:36 #39547Michala MackayGuest
location of bts sites – any international regulation prescribing the minimum distance to exist between bts sites of different operators?
disadvantages of building a site less then 100m from an already installed bts site.
grateful for any assistance.
Best Regards8th August 2006 at 07:17 #39548MannGuest
Hi all, m working as FLM engg with nokia BTS. recently I have faced a problem where calls cannot be completed. everytime we dial a no, we get “call disconnected” without any reason.
The BTS is not having abnormal VSWR. Can nyont tell the reason?8th August 2006 at 14:53 #39549PixGuest
it might be a sector inversion, or a hardware failure from a TRE or ANC (combiner), or a hardware failure from the transcoder,
You ought to perform some detailed Abis traces :
when does the call stops ? (AGCH, SDCCH, TCH phases ?)
on which TRE are you on ?
does it drop on all TRE ?
does it drop on the other sectors too ?
are the other BTS on the same Abis link impacted too ?
on the whole transcoder ?
on all the BTS of the same transcoder’s TCU ?
I hope it can help… those are just possibilities. Try also to go in the cell with an handover, instead of a call setup. And check out your QoS indicators, what are they telling you ?9th August 2006 at 06:41 #39550MannGuest
I’ll try wid wat u have suggested. I had already checked on which TRXs and sectors the pro is. And its not trx or sector specific. Calls are getting disconnected in every sector.
But, its happening only in one particular BTS of the transcoder. Even i suspect a faulty combiner and replacing it 2day. lets hope the prob sees off.12th August 2006 at 06:32 #39551anant aggarwalGuest
I want to know about different of anteena and their gain used in GSM? and the manufacturing detail of anteena?13th August 2006 at 05:28 #39552yellaiahGuest
hai , can any help on Diversity principle used in GSM.
with regards14th August 2006 at 17:49 #39553oscarGuest
I am new in this area, for this a need information about BTS Ericcson.
Oscar15th August 2006 at 07:02 #39554rafiGuest
BTS(Base transceiver System)is a set of equipment to handle a cell in GSM. BTS consists of transmitters, receivers, CDUs,power supplies and antennae. Each GSM site may be configured in two or three sectors and each sector is provided with four hannels.For GSM, RBS200 series and 2000 series were used. Now 2206 is extensively used. For WCDMA RBS300 series is introduced.15th August 2006 at 08:35 #39555RafiGuest
GSM is an old version of mobile communication where TDMA is utilised while CDMA is new one where codes are allotted to each mobile user.3G is WCDMA(Wideband code division multiple access, BW=5MHZ)is a further development of CDMA(BW=1.25MHZ)having a number of applications.Capacity of CDMA is much more comparing to GSM and it is flexible.If a channel accomodates 80 users in CDMA, it can accomodate further more at the cost of quality and coverage.As number of users increase noise
increases and coverage reduces due to a phenomena called cell breathing.Unlike GSM where frequency planning is required using a number of frequencies, code planning is required in CDMA using same frequency in adjacent cells without any interference.15th August 2006 at 12:57 #39556ArnGuest
I am electrnic and communication engr, i want to enhanced more my knowledge regarding GSM networks, like MIcrowave installation, BTS intallation, Integration and others. Anyone can help me and send me data to be read…
thanks to all
hoping for your respond15th August 2006 at 13:44 #39557rafiGuest
In Wireless communications, two types of diversities are used.
1 . Frequency Diversity: Here signal is transmitted on two different frequencies and signals from both carriers combined at receiver end to recover it. Space attenuation is different for different frequencies. If one frequency is attenuated, the other one is strong enough to be used at receiver end and addition of two produces good signal.
2 . Space Diversity: Due to changes in the environment, signal is bent in the vertical direction. On receiver side two antennae are installed on tower with a space between them receiving same frequency and their signals are combined together for good quality.16th August 2006 at 10:43 #39558123Guest
any one knows how to measure signal strength using mobile? and what mobile can be use to measure the signal strength in decibels17th August 2006 at 12:18 #39559yellaiahGuest
thanks for ur suggestion regarding Diversity..