SDCCH blocking is high

anit
increase the TX-integer so that the collision will be reduced.

Hi aso ,

if u have tx integer 10 and if u increase upto 50 then i think is there any chance to increase the call set up time? and by increasing the tx rach failure will be decrease?

i want to clear the meaning of tx = its time between rach retransmission. ok is it right?

Hi Krish
There is a subtle difference between Max. no. of retransmissions & Tx-Integer.
Tx: It indicates the number of time slots in an interval when an MS sends continuously multiple channel requests.To reduce the collisions on the RACH and to raise the efficiency of the RACH, access algorithm is defined This parameter works together with the configuration of the CCCH(parameter S)When T increases, the interval between two adjacent channel requests increases, and RACH conflicts decrease.

When S increases, the interval between two adjacent channel requests increases, and RACH conflicts decrease, thus improving the usage of AGCH and SDCCH.

The access time of the MS, however, is prolonged and the network performance is threatened when T and S increase. Thus, an appropriate T value should be adopted to ensure that S is as low as possible, and that AGCH and SDCCH are not overloaded

the analysis of QoS KPI SDCCH always read between 0.6 t0 0.86 % on the average.
pls what is responsible for this high value

Hi Yogesh,

Here are some possibilities:

1. Check your frequency plan and make sure it’s good…this is fundamental.

2. Check your hopping parameters (HSN and MAIOs, hopping reuse pattern, etc)

3. Make sure you use regular antenna azimuths throughout the network as much as possible. Also make sure your cells are not overshooting.

4. Activate power control and DTX if you haven’t done that already.

5. Check for faulty TRXs.

6. Check your network synchronisation

7. Check for external interference.

Regards,
SHELDON

Hi, this is santhakumar..how to reduce penetration of side lobe of an antenna?
other then applying electrical tilt and POC value?

hi santakhumar,

there are some metallic devices that can be used to reduce the side lobes (like deflectors panels on each side of the antenna)… but i never saw that on the field. It probably works only on very specific antenna models.

If you don’t want the electrical tilt then the only other solution is to change the antenna. Buy one which has a narrower Horizontal-HPBW.

Regards
pix

What is Side Lobe Attenutaion in Antennas?. How to calculate it?