One reason to use an offset might be that some algorithms don't work
well near DC. If I remember correctly, an example of this would be
the Hilbert Transform. I don't know the internals of Flex so I've no
idea if they do it this way or not.
I believe that thresholding a sine wave would increase jitter rather
than decrease it.
ward
On Oct 22, 2009, at 11:51 AM, Randy Rogers wrote:
my question was why the flex-radio system is offset from the lo by
11Khz.
if there is clock jitter in the sampling system that same jitter
would also be present at the offset.
From: Guido <[email protected]>
To: [email protected]
Sent: Thu, October 22, 2009 11:46:34 AM
Subject: Re: [soft_radio] Quadrature Sampling Detector Questions
On Thu, Oct 22, 2009 at 7:34 PM, Alberto I2PHD
<[email protected]> wrote:
ad7zu wrote:
Although I would not expect phase noise to be a factor since
the bus switch does not turn on until the enable signal is above 1v.
Phase noise translates into timing jitter, so you cannot have hopes
to avoid it
by simply thresholding the amplitudes....
Wonder if thresholding a sine wave is increasing the phase noise.
When thresholded the period jitter is soley based on a single
instance of the amplitude transition, while phase errors during for
the full sine period could average out period jitter. Or is this not
the case?
73, Guido
PE1NNZ
