Re: 60CX / 76CX and WAAS

Wolfgang S. Rupprecht wrote:
. . .
They may be doing more than just cranking up the RF gain. From
reading the one-page pdf "glossy" at
http://www.sirf.com/products-ss3.html (see "For more information"),
the sirf-III chip has a massive correlator. That might allow it to
process a signal out of the noise without cranking up the gain.

Increasing gain is trivial to do but does nothing to improve reception. What you need to do is increase the signal/noise ratio. A lower noise front-end amplifier will help; one with the same noise figure but greater gain doesn't help at all -- it just makes both the signal and the noise bigger. There are of course other ways to improve the signal/noise ratio, like more advanced processing. Sounds like that's the main technique they're using.

Roy Lewallen
.

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