Re: [Discuss-gnuradio] Designing a good receiver

[Brian Padalino]

On Thu, Jun 2, 2011 at 7:10 AM, Mike Clark <address@hidden> wrote:
> This comes from a discussion over on the USRP-users mailing list, but
> I felt it would be more appropriate to post here. Over on that list,
> someone was asking about problems they were having consistently
> receiving data on their USRP. My background is in CS, not RF comms, so
> please forgive me as I'm sure the answer will be fairly standard :)
>
> Anyways, the question I have is, is there a general procedure one can
> follow to design a decent receiver in gnuradio? For example, I have a
> project that I'm using for experimentation where my receiver looks
> like this: USRP Source -> GMSK Demod -> Packet Decoder -> File Sink.
> This works well when I have the USRPs cabled together and even when I
> have antennas with line of sight (I haven't checked max distance).
> When I don't have line of sight, however, I stop receiving packets.
> Are there any other gnuradio blocks I can add in to my setup which
> will help get better performance when there is no line of sight? I
> haven't tested it, but my guess is that when there is no line of
> sight, there must be a frequency shift or something of that nature
> happening which ruins the connection.

Transmitting is the easy part, it's the receiving that is difficult.

Recently, there were some articles printed by EE Times about propagation:

    http://www.eetimes.com/ContentEETimes/Documents/McClaning_3_pt1.pdf
    http://www.eetimes.com/ContentEETimes/Documents/McClaning_3_pt2.pdf

They are from the book Wireless Receiver Design for Digital
Communications, 2nd Edition, by Kevin McClaning.  This is probably
good reading in general.

Good luck.

Brian