Re: [Discuss-gnuradio] Gnuradio Mode S project released

[Nick Foster]

On Sun, 2010-10-24 at 19:22 +0200, Andrea Montefusco wrote:
> Nick,
> 
> is it thinkable to operate the decoder at a lower sample rate ?
> (e.g. at 2 MS/s or even less)

Mode S operates at 1Mbit/s bit rate, and being pulse-position-modulated
the data rate is effectively 2Mchips/s. In order to guarantee at least
one sample falls reasonably close to the center of the chip you have to
sample multiple points per chip. If you could ensure somehow that your
samples were aligned with the chip centers, you could sample at 2Msps.

Nick

> 
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