- This topic has 409 replies, 1 voice, and was last updated 14 years, 6 months ago by Dude.
25th April 2003 at 15:17 #33828NickGuest
if you can send your answer for AT’s question to the forum, we can also learn sth. Thanks.6th May 2003 at 10:22 #33829RikiGuest
I need specification about BTS or RBS antenna for GSM. Could anyone help me ?7th May 2003 at 04:42 #33830PaulGuest
There are various anntenna models available from Kathrein or Algon that have an adjustable electrical tilt. I haven’t seen one that you have to change ports to effect the change. Most come with the a adjustment knob/dial on the bottom or back of antenna.
The Kathrein 742 047 is an example of a dual band, 4 arrays ( 2 +45 degree and 2 -45 degree ) where the 900 array can have it’s elec tilt adjusted.
As for horizontal or vertical polarisation, it’s not correct to say that hp is more attenuated than vp.
Consider that in space there is no such think as vertical or horizontal and no matter how you rotate the antenna it will propagate the same.
However because of different effect that V and H polarised waves encounter when being reflected off the ground and other objects, V waves tend to keep their polarisation, while H waves then to get rotated and suffer higher relection losses.
To Rachid and Mostafa:
E///’s definition for Sudden Loss is compatible to Mostafa’s definition of “other”.
However please not that the “due to” is not exactly correct. The statistics only tell you that at the time of the drop there was a Bad Quality, Low Signal Strength, or exessive TA urgency state (or none in the case of other or sudden loss).
Depending on the thresholds you set for what is low SS or bad Qual or excessive TA, the validity of these stats can be questioned.7th May 2003 at 19:14 #33831MostafaGuest
I think /due to/ is correct for the reason that all the definition is taken from :”Network performance improvement description for the area dropped calls” Document ID :”LVR/P-97:0437 Rev B 1999-14-02″ delivred by Ericsson to customers.
Friendly.20th May 2003 at 16:50 #33832sadieGuest
has anyone come across the tool ASSET from AIRCOM if so, have they come across the problem with the discrepeny table report discepencies across a 900/1800 dual band network. From what I know these tables should be sperate28th May 2003 at 21:48 #33833BruceGuest
Could you please tell me what is difference between Rxlev(Full) and Rxlev(Sub).
Regards29th May 2003 at 01:14 #33834SatishGuest
In GSM, there are two types of values presented for RXQUAL, namely RXQUAL FULL and RXQUAL SUB, RXLEV, the parameter representing the signal strength also has similar FULL and SUB values.
The FULL values are based upon all frames on the SACCH multiframe, whether they have been transmitted from the base station or not. This means that if DTX DL has been used the FULL values will be invalid for that period since they include bit error measurements at periods where nothing has been sent resulting in very high BER.
In total, 100 bursts (i.e. 25 blocks) will be used for the FULL values.
The SUB values are based on the mandatory frames on the SACCH multiframe i.e. frames that always must be transmitted. There are two frames fulfilling that criteria and that is SCACCH block and the block holding the SID frame. If DTX DL is not in use, the SID frame will contain an ordinary speech frame and then this is included instead. In total 12 bursts (2 blocks) will be used for the SUB values (4 bursts SACCH and 8 halfbursts SID (or speech) information).30th May 2003 at 00:51 #33835SatishGuest
Can any one tell me how to change the encryotion from A 5/1 to A 5/2 in Ericsson RBS2302.
Is it just a software change or hardware change ?
Regards30th May 2003 at 13:16 #33836BruceGuest
Can any one tell me if a high rate of VSWR on antenna system may cause drop call?
Thanks.30th May 2003 at 16:12 #33837JoeGuest
I’m looking for someone with Motorola GSM BSS experience. In particular, I’m looking for the correct definition of the dropcall rate formula for the Motorola system. Also how is this formula kept accurate when a dropcall happens when moving from one BSC to another?
Joe30th May 2003 at 19:24 #33838MostafaGuest
I think taht TRXs are designed for a special encryption algorithm, so its hardware definiton.8th June 2003 at 10:05 #33839Imran IdreesGuest
I have been working on SIEMENS d900 mobile switching center for the last four years. I can help you guys in any related field inmcluding NSS planning.9th June 2003 at 10:17 #33840ATGuest
whats ur email address. send it to me on firstname.lastname@example.org… i wud like to discuss with u few issues on siemens NSS planning. i have also been discussing it with amin sudhir on this forum and wud like to discuss some issues amongst us
at9th June 2003 at 11:30 #33841SachinGuest
i am working on lucent BTS(modcel 3.0) for CDMA network. i am facing echo problem during the call.
plz tell me how i cam overcome this prob.
sachin18th June 2003 at 15:21 #33842Hi IMRAN…and ATGuest
I am not working in D900 but worked for some time…one month but never touched..
But I like to have some basic knowledge through you guys .
mail me your mail ids….