Re: [Discuss-gnuradio] pll_refout_cc - finding optimum alpha & beta ??

[ldoolitt]

On Fri, Mar 17, 2006 at 05:32:20PM -0500, Charles Swiger wrote:
> On Fri, 2006-03-17 at 14:46 -0500, Charles Swiger wrote:
> > There must be a trivial way to change +7.5kHz to -7.5kHz so we can use
> > complex mixing...
> > 
> 
> Ah ha - it's invert either I or Q.
> 
> c2f = gr.complex_to_float()
> phase1 = gr.multiply_const_ff(-1)
> phase2 = gr.multiply_const_ff(1)
> f2c = gr.float_to_complex()
> 
> fg.connect((c2f,0),phase1,(f2c,0))
> fg.connect((c2f,1),phase2,(f2c,1))
> 
> f in, -f out.

A mathematician calls this operation "complex conjugate".
If it's not already in the gnuradio toolkit, it should be.

    - Larry