Is there any correlation between SSF and interference in TDD?

gdtelecomm · February 12, 2022, 3:00am

Dear Experts.

By changing SSF interference issue can be mitigated?

Saurabh63 · March 22, 2022, 5:28pm

Yes, there is.

vikram · March 22, 2022, 5:29pm

Yes, we have seen this.
We reconfigured ssf from 7 to 5 for hilly areas like Himachal and Utrakhand (in India), and this brings improvement in RSSI.

gdtelecomm · March 22, 2022, 5:30pm

How does it improve? Can you elaborate please?

vikram · March 22, 2022, 5:32pm

As per my understanding it’s because of allowing greater guard period in ssf5 compare to ss7.

There could also be many more things which will come into picture. (I am sorry I am not aware about them as of now).

gdtelecomm · March 22, 2022, 5:32pm

Thanks a lot!
So basically higher GP mitigates interference issue.

vikram · March 22, 2022, 5:33pm

Yes, I believe so.

Saurabh63 · March 22, 2022, 5:34pm

Yes that’s correct.

I have seen same thing in UP west region having high UL interference in complete area.

That time SSF7 was changed to SSF5 and complete area UL interference was gone.

onkar.ghatpande · March 22, 2022, 5:37pm

Yes only from aggressor from distance 42 km to 192 km.

For less than 42 km distance, 2 symbols GP gap won’t allow aggressor interfere with victim and for greater than 192 km, even though we convert ssf7 to 5 to make GP of 9 symbols, aggressor start to hit 1st symbols of uwpts of victims.

Also ssf conversion must be done at aggressor, not at victim but finding victim is very easy from rssi counters, finding correct aggressor is tough job.

gdtelecomm · March 22, 2022, 5:38pm

Thanks!

Normally how do we find correct aggressor?