[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Discuss-gnuradio] QPSK phase noise
From: |
Paco Garcia |
Subject: |
[Discuss-gnuradio] QPSK phase noise |
Date: |
Tue, 7 Apr 2009 11:07:54 -0700 (PDT) |
Dear All,
I am trying to demod a qpsk from another USRP but with the setup below I get
a really noisy constellation:
http://img231.imageshack.us/img231/2465/screenshotysh.png
The 2 USRPs are connected via a SMA cable with 40 db attenuators and DC
blocker.
I have also played with the costas alpha, samples per symbol, gain mu,
frequency fine tunning and this is the best result I can get.
./benchmark_tx.py -m dqpsk -f 1.25G -m dqpsk --tx-amplitude=10000 -r 1M -M
99999999 --excess-bw=0.35
./benchmark_rx.py -r 1M -m dqpsk --log --costas-alpha=0.05 -S 4 --verbose -r
1M --gain-mu=0.01 --excess-bw=0.35 -f 1.25G
Thanks for your help.
--
View this message in context:
http://www.nabble.com/QPSK-phase-noise-tp22934944p22934944.html
Sent from the GnuRadio mailing list archive at Nabble.com.
- [Discuss-gnuradio] QPSK phase noise,
Paco Garcia <=