How to reduce data rate in OFDM

GNU Radio
1

Hi all,
My current equipment seems can’t handle normal parameter setting
for
OFDM test. The receiver can only receive very small number of packet
correctly. One possible reason maybe because the host can’t catch up the
process speed. So, I would like to modify some paramters and reduce the
process burden on the cpu side. I noticed the bandwidth can be reduce by
given maximum interpolation/decimation numbers. If I reduce fft-length
it
might also make the cpu easy. However, even after I tried the following
parameters, the output is still very bad. Does any one have any
suggestion?
./benchmark_ofdm_rx.py -f 40M -d 256 --fft-length=32 --occupied-tones=16
–cp-length=2
./benchmark_ofdm_tx.py -f 40M -i 512 --fft-length=32 --occupied-tones=16
–cp-length=2

Thanks,
Bin Zan

2

correctly. One possible reason maybe because the host can’t catch up the
process speed. So, I would like to modify some paramters and reduce the
process burden on the cpu side. I noticed the bandwidth can be reduce by

A few questions:

  1. What radio hardware are you using?
  2. What PC hardware are you using?
  3. Are you seeing output similar to the following
    “uUuUuUuUuUuUuUuUuOuOuUuOu” ?
  4. Are you using 2 separate PCs for the tx/rx?

Jason

3
  1. What radio hardware are you using?

Just Basic Tx/Rx

  1. What PC hardware are you using?

PC with a 1 GHz VIA C3 processor, 512 MB of RAM, 20 GB of local disk

  1. Are you seeing output similar to the following
    “uUuUuUuUuUuUuUuUuOuOuUuOu” ?

Yes, uOuO

  1. Are you using 2 separate PCs for the tx/rx?

I have two PCs, one was transmitting, and the other one was receiving.