Subband CQI and Wideband CQI

Dear Experts,
Regarindg subband cqi and wideband cqi lte and periodiccqi and apperiodiccqi.
Why mostly subband cqi is preferred and why both periodiccqi and aperiodiccqi selected? .
In good cqi cells, can’t apperiodic cqi be deselected for improving throughput?

Most of time wideband cqi preferred.

But it needs entire bandwidth for UE, for estimation.

Yes, but cqi reporting and estimation can be done in better way at eNodeB.

Yes, but subband can check interference too in a proper way.

For periodic /aperiodic we have parameter to control…observed some devices having issue with aperiodic cqi reporting.
In my view it can set to false.

As compared to wideband.
But poor RF conditions will need apperiodic cqi or else there can be issues.
Does high utilized sites can be done wideband cqi and less as subband cqi?

I will tell you issue observed: it’s with tm8 mode.

If RF is good, tm8, subband cqi is frequency selective scheduling.