GMSK with frequency-selective Rayleigh fading and cochannel interference

The author derives a formula for error probability of partial-response continuous-phase modulation with differential phase detector and limiter discriminator detector in a multipath Rayleigh fading channel, taking into account frequency-selective fading, cochannel interference, Doppler frequency shift, and additive Gaussian noise while the receiver rejects a specified amount of adjacent channel interference. A formula for the error floor is also presented. Numerical results are presented for Gaussian minimum shift keying with a premodulation normalized filter bandwidth of 0.25. Under mild channel conditions and low energy-to-noise ratios, the best detector is an optimized two-bit differential detection; otherwise the best detector is the limiter discriminator detector