Re: [Discuss-gnuradio] implement d8psk on benchmark_tx.py

[David I. Emery]

On Mon, Feb 16, 2009 at 08:30:26PM -0800, Firas Abbas wrote:
> Hi,
> 
> > On Tue, 2/17/09, George Nychis <address@hidden> wrote:
> 
> > Hello, Tianning/Bill/Daniel!
> > 
> > The performance of 8PSK matches pretty similarly to 16-QAM.
> >  So, 8PSK is usually never used in a real system as you get
> > better spectral efficiency with 16-QAM without taking a huge
> > hit in required SNR.
> > 
> > - Rick Stevens
> 
> 8PSK modulation is widely used by VSAT modems for SCPC-SCPC links.

        And for both DTH (DirecTV and Dish HD) and broadcast/cable
satellite signal distribution... witness the DVB-S2 8PSK modes being
rapidly deployed and the older DSNG-trellis 8PSK.

        It is prefered for the non-linear environment of satellite
transponders with significant HPA compression... 16-QAM takes better
linearity... and many satellite channels are power rather than BW limited.


-- 
  Dave Emery N1PRE/AE, address@hidden  DIE Consulting, Weston, Mass 02493
"An empty zombie mind with a forlorn barely readable weatherbeaten
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