after copy–> paste the code you should change the ‘ ‘ sign because it will not paseted in the correct shape.( i.e randn(’state’,200) ), and the all commas shall be changed

The third demod method (c) seems to refer to the OPTIMUM NON-COHERENT (or, as some authors define it, the optimum differentially coherent) dbpsk demodulation method (and its theoretical performance)

(a) and (b) requires phase tracking since thay can merely tolerate phase errors and can not tolerate any frequency errors (except for very short bursts)

(c) on the other hand, can tolerate a limited amount of frequency error and is not affected by phase errors at all. In (c) receiver produces a random phase copy of the carrier tone (not necessarily phase matched to received signal’s tone). Hence, it requires only a frequency estimator. Tracking is optional, and one can use a simpler tracker, with a first order loop filter without any cost, (whereas first order loop filtered tracker will cause phase bias and performance degradation in (a) and (b))

All these are fine, but I would like to compare the effect of Phase Jitter and/or the timing jitter of the ADC used in the receiver. (c) is not necessarily more immune to jitter than (a) and (b). Or is it?

There is also a fourth option, using a sub-optimum non-coherent receiver (as is defined in “Digital Modulation techniques” by Fuqin Xiong, Chapter 4.2) that does NOT produce a copy of the carrier tone (phase matched or otherwise). This receiver merely band pass filters the incoming IF (intermediate frequency) signal and multiplies with delayed version of itself, then integrates for the symbol period to get detector outputs. Theoretically, the cost in performance is about 1 dB.

My question is: How does the tolerance of this fourth option to ADC timing jitter, compares to other types of receivers? Does the fourth method have significantly more tolerance to jitter than (c) ? Does anyone have any experience on this type of system?

Best Regards