The Weaver method is sometimes called the third method
of generating SSB. Phasing and filtering being the
other two. In a weaver you down shift the baseband
signal so that the center is at DC and then put the
signal through low pass filters which are easier to
build digitally. The system then upshifts the signals
back to IF and adds/subtracts them to get IF output.
Weaver wrote a paper on this in 1956. The appeal of
the Weaver is the low pass filters in lieu of bandpass
filters which are used is a normal phased system.
Smith shows one in block diagram form in his book
"Digital Signal Processing" on page 5-10.
73,
John NA9U
--- Ron Castro <ronc@sonic.net> wrote:
> That info came from a reader of this reflector who
> e-mailed me yesterday
> off-list after seeing our discussion. He went on to
> say that the Weaver
> method uses low pass filters instead of band pass
> filters, which are easier
> to implement in DSP. I honestly don't know how that
> works, but if I take
> the time to read and really understand the articles
> on Doug Smith's website,
> I might get a little more informed.
>
> Ron N6AHA
>
>
> ----- Original Message -----
> From: "Martin, AA6E" <martin.ewing@gmail.com>
> To: "Discussion of Ten-Tec Equipment"
> <tentec@contesting.com>
> Sent: Friday, April 07, 2006 2:11 PM
> Subject: Re: [TenTec] "The Bug" a/k/a Orion II Audio
>
>
> > On 4/7/06, Ron Castro <ronc@sonic.net> wrote:
> >>
> >>
> >> * Audio problem that was apparently caused
> by a change in the DSP
> >> from a filter method to the "Weaver Phase
> Difference" method.
> >
> >
> > I was interested in that remark about the "Weaver
> Phase Difference"
> > method.
> > How do we know what algorithms are in use in the
> Orion? I think Bill W4ZV
> > made reference to this a while back. [I'm not
> familiar with this technique
> > -- does it intrinsically have more trouble
> delivering hi fi results for a
> > given CPU power?]
> >
>
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
>
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