discuss-gnuradio
[Top][All Lists]
Advanced

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

Re: [Discuss-gnuradio] What happens to incoming data if a block is too s


From: Johnathan Corgan
Subject: Re: [Discuss-gnuradio] What happens to incoming data if a block is too slow?
Date: Mon, 13 Jun 2011 17:23:30 -0700

On Mon, Jun 13, 2011 at 17:06, Marcus D. Leech <address@hidden> wrote:
 
As long as overruns aren't happening *frequently* (like more than once every few dozen higher-layer-data-frames), then one can regard
 such interrupts in data flow as equivalent to channel noise, which is something you have to cope with *regardless*--even if your
 sample stream is "perfect".

In fact, if your channel model makes brash assumptions like the only "noise" will be from the "natural physics" of the channel, then you've
 already entered a state of sin.  In general, radio channels aren't well-behaved with regard to "goop" on the channel, and I regard sampling
 overruns, at a 10,000ft level, as broadly-equivalent to "channel goop".

To a receiver, these appear as instantaneous phase jumps--which can, for some modulations, take a long time to recover from.  At least now with UHD one can update the receiver's notion of sample number/timebase accurately when such a gap occurs.

Johnathan

reply via email to

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