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RF engineer
2009-03-26, 05:14 AM
Can any one help more about 4way diversity and transmit diversity , already i attached the trial doc but i would like to have more opinion on this issue especially how to configured in the network ( huawei vendor)
Thanks for your help

giegala
2009-03-26, 06:58 PM
Hi,

I have seen those E/// presentations on 4-way GSM RX diversity and I did not like them. This document looks like just an article on the same trial.

4-way diversity gives rather small gain (0-2dB) over 2 way diversity. If you have TMA installed then they give you 10dB gain. If you look from UL-DL balance perspective, is that 4-way diversity gain realy worth it? Mostly likely UL budget will be much bigger that DL.

To implement 4-way diversity, you will need spacial antenna separation. This gives you most of the gain only on the main beamwidth (only the central part of it) but not sideways.

Considering TX diversity, e/// provides some signal boost by operating 2 sinchronised TRX. If they are configured on different antennas, this will provide some sort of ISI (signal self-interference) and there's a big gamble if handsets can properly equalise signal and combine the energy from different paths. I think better gain could be acheived by putting DL signal booster (TMB) on top of the mast.

I have no idea on how to configure Huawei, as I never worked on that equipment.

Good luck with trials!

RF engineer
2009-03-26, 07:37 PM
Dear giegala
Thanks for your support and do you have any technical doc for any other vendors to describe the 4 way diversity

sanjay
2009-06-01, 03:46 AM
Hi

can u pls give access to dowload the 4 way diversity doc .

thnks
sanjay

RF engineer
2009-06-01, 07:56 PM
I think you have problem in your balance send me your mail to send you

destny6969
2009-10-27, 07:04 AM
thank for sharing bro 's