Timing/preamble trigger output from the OFDM receiver

Hi there,

I am logging the output 1 of the ofdm_sync block (i.e., the timing
triggers after the timing synchronization) and the output 1 of the
ofdm_frame_aq block (i.e., the preamble triggers after both fine and
coarse frequency synchronization). I saw varied gaps between adjacent
values in these two streams.

For example, using the default OFDM sender/receiver parameters (pkt
size=90 bytes), in one run, I got gaps in the former stream like these:
3200 3199 3200 3200 3200 3199 3200 3199 3202
3198 3201 3197 3200 3202 3200… The gaps in
the latter stream like these: 1000 1000 1000 1000 1000
1000 1000 1000 1200 1000 1000 1000 1000 1200
1000 1200…

I wonder why the gaps are not the same.

Note that I modified the latter stream so that it contains zeros and
ones for each ‘occupied bin’ rather than each ‘OFDM symbol’.

Thanks
Tianji