patrick.melet@dmradiocom.fr wrote:

> Hi,
> 
> Is it possible to demodulate the 8 PSK modulation with a differentiel
> demodulator and without a Costas Loop ?

Yes. If the loss of ~3dB in the SNR is tolerable.

Vladimir Vassilevsky

DSP and Mixed Signal Design Consultant

http://www.abvolt.com

patrick.melet@dmradiocom.fr writes:

> Hi,
>
> Is it possible to demodulate the 8 PSK modulation with a differentiel
> demodulator and without a Costas Loop ?

You must have timing, i.e., Costas loop or somesuch.

You can use a differential demodulator if you have a reference
sequence to get back the absolute phase, but why do this? You
lose 3 dB in performance.
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Hi,

Is it possible to demodulate the 8 PSK modulation with a differentiel
demodulator and without a Costas Loop ?

thanks...