[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] Run USRP at alternate clock frequency?

From: Lee Patton
Subject: Re: [Discuss-gnuradio] Run USRP at alternate clock frequency?
Date: Thu, 06 Apr 2006 18:22:35 -0400

> > Reran my custom dbs program and it worked fine EXCEPT:
> > The default decimation is 4 so I'm recording at 11 megasamples per 
> > second. (oddly enough I'm still able to demodulate my 802.11b packets 
> > fine even though the chip rate is 11 mcps!?) When I try a decimation 
> > rate of 2 I get the message:
> Will you be sharing this code?
> I think more people will be interested in doing 802.11b.

Count me as interested!

> > If necessary I will go modify that fpga to just have a halfband so I can 
> > record at 22 complex megasamples per second which is enough bandwidth to 
> > support 802.11a/g. Can't beat more bandwidth at less power.:)
> It will be interesting to see if you will be able to get complex 8 bit 
> samples over the bus with decimation 2.
> This will be 44 Mbyte/sec over the usb bus. This is within the theoretical 
> limits of usb2 but until now I have not heard of anybody being able to 
> sustain more 
> then 32 Mbyte/sec over the bus using the usrp.

Martin, you gave us the -8 option did you not? How about a -6 option so
we can squeeze the data over the bus?  Think SNR will be degraded too
much in that case?

Disclaimer: I know nothing about verilog/FPGA, and may have just asked a
very stupid question. 8 bits sounds like a nice number, and 6 sounds
less than convenient, but maybe it doesn't matter if it is truly a bit

 - Lee

reply via email to

[Prev in Thread] Current Thread [Next in Thread]