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I am Modulating the bits using FSK and PSK modulators and sending them to the demodulator and the demodulator is using simple zero crossing detection to detect the bits.

But the problem is, when I introduce a chennel between the modulator and demodulator, the channel output has many transitions going on and the detection fails some how.

So I am looking for any detection algorithm in Matlab, that does the perfect detection in a lossy and delay induced channel.

PS: When we calculate the BER of this communication system, we calculate irrespctive of out detection method ? I mean like, if my detection method is powerful then Bit Errors prone to happen more, and then should I blame that on that channel performance ? that is absolutely wrong I guess. So How can one know that he has the better detection algorithm in place before calculating the BER.

Hope I made my points clear, please let me know if you need more explanation, I am happy to provide.

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    \$\begingroup\$ analog demodulators use the entire phase amplitude cycle and not just the edges and often shown as multipliers. One the signal is digitized or converted to digital phase or sliced with a comparator the noise spectrum or slope of SNR to bits of bandwidth is used to extrapolate BER for longer intervals. For PSK coherent detection is required derived from clock recovery, for complex PSK, like trellis coding, phase estimators limit options for next phase, multiple FEC is also possible with digital radios \$\endgroup\$ – Sunnyskyguy EE75 Oct 8 '16 at 13:57
  • \$\begingroup\$ consider also the concept of the ideal receiver that uses an IF filter where the shape matches the spectrum of the signal for optimal SNR with minimal ISI \$\endgroup\$ – Sunnyskyguy EE75 Oct 8 '16 at 14:06
  • \$\begingroup\$ @TonyStewart.EEsince'75...I will try to go through the suggestions you made. May I know what is your take on the post script in my question. i would like to know in general, How can one know he has reached the optimal detection strategy and at what point he can test the BER. ? \$\endgroup\$ – gocjack Oct 8 '16 at 14:20

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