- This topic has 4 replies, 1 voice, and was last updated 7 years, 6 months ago by pix.
26th March 2013 at 15:36 #68973JamesGuest
by shifting SD from CHGR 1 to CHGR0 giving improvement.
Try understand logic behind that. Like if the SDCCH were put on the BCCH frequency and the frequency plan were different for the BCCH than for non-BCCH frequencies. It is possible that the interference situation is worse on the BCCH, thereby causing a relatively high percentage of drops on SDCCH compared to TCH.
Kindly share our views & try this.
You will get very good improvement in CNDROP.14th August 2013 at 16:03 #68974JamesGuest
Still waiting for your expert comments.15th August 2013 at 17:05 #68975pixGuest
the CHGR0 is on the BCCH frequency, which is usually using a frequency plan a little cleaner than the CHGR1.
As a result, it is not surprising to have better QOS on CHGR0 than on CHGR1.
I’ve heard that we have noticed that on our network too, but I didn’t work on it myself.
What’s sure is that if there is a SDCCH ts on CHGR1, then it will be the one that will be used first. Once this SDCCH is full, then the one on CHGR0 will be used.
See if the SD Drop rate occurs for LU or for non-LU. If mostly for LU, then consider than MS are right at the cell border, therefore any slight change in interference will have a big impact.
Pix16th August 2013 at 11:55 #68976JamesGuest
Many Thnx Pix,
For my cases i have massive improvement in SD Drop,CNDROP by SD shifting. What i know that BCCH TRX is always clean & tx on max power so impacting better on SD.Also let me know parameter to be use for SD Drops improvement other than normal ones for ericsson. C/I,overshooting,HW issue all checked.16th August 2013 at 17:30 #68977pixGuest
can you quantify the SD DROP% improvement ?
also, how many frequencies are allocated for BCCH band, and for TCH band ?
What hopping type are you using on CHGR1 ?
how hopping frequencies ber MA list ?
how many TRX per cell, in average ?