Very low packet loss rate for the discontinuous BPSK communications- the analysis and looking for so

Hello,

In the current gr-digital/narrowband, I am using the benchmark_tx.py and
rx.py to test the bpsk communications.
It is found that the packet loss rate is very high (70% loss) in
discontinuous mode where every 5 packets are in a burst. But in
continuous
mode, the paket loss rate is less than 10% for the same point to point
link.

I captured the waveform data. From the observed result, it seems that
for
each burst (5 packet), the bpsk receiver needs to re-do the
frequency/time
sync. This will directly causes that the first packet of each burst will
definitely be crashed. Also, some burst can not be demodulated correctly
at
all. For the same reason, even in the continuous mode, the very first
packet is also crashed at the receiver.

I have tried to add very long preamble for each packet to ensure the
data
part of the packet can be received in well sync status. But the result
is
not very good.

Before I get further investigation on the solutions, just wondering if
any
ideas or existing work within this community.

Alex,
Dreams can come true just believe.

Seems no one can shed a light on this topic?

On Thu, Feb 28, 2013 at 10:25 PM, Alex Z.
[email protected]wrote:

each burst (5 packet), the bpsk receiver needs to re-do the frequency/time
ideas or existing work within this community.

Alex,
Dreams can come true just believe.

Alex,
Dreams can come true just believe.