Well, SFN only works properly if the transmitter clocks (on the same frequency at least) are in perfect sync and the CP is configured properly for all transmitters. If any transmitters clock is out of line or the CP is incorrect/not sufficient, you will have severe interference. I assume the CP is set correctly on all transmitters.
What type of sync solution are you using? GPS, SyncE, 1588 V2?
Be careful during the measurement, as the R&S analyzers clock needs to be synchronized to the same source as the transmitters, otherwise you will measure false results. The clock/timing accuracy needs to be measured one by one (every time the analyzers clock needs to be on the same source as the transmitter), and you will find which transmitter's clock is out of line. I would also do measurements on the clock sources separately as well, to see if the source itself is at fault/out of line, or the transmitter's PLL/OCXO is at fault.
I dont know at which part, but the maximum allowed frequency and timing errors can be found in the DVB-T2 specifications for sure.
If you have better resolution images, that would be awesome.
Bookmarks