27 Jun
2011
27 Jun
'11
12:01 a.m.
On Sun, 26 Jun 2011 14:54:48 -0400
gene heskett <gheskett(a)wdtv.com> wrote:
I do not see how a repeatable, and therefore
measurable quadrature
component can be developed in a complex, multi-frequency waveform since the
quadrature component is just as frequency dependent as any other method of
measurement.
Really? Because I'm generating some quadrature samples right now - they're how
software-defined radios work. In this case you generate two local oscillators 90 degrees
apart and use them to switch a pair of synchronous detectors. The resulting downmixed RF
is now at audio frequencies (just like a direct-conversion receiver) and can be passed to
a soundcard, then processed on the PC to extract a particular signal.
See https://github.com/gordonjcp/lysdr if you want to play.
Gordon MM0YEQ