Noncoherently detected trellis-coded partial response CPM on mobile radio channels

This paper presents a noncoherent receiver for partial response trellis-coded continuous phase modulation (TC-CPM) on interleaved flat Rician fading channels. By using a multiple-symbol observation interval and a simple metric calculator, the power efficiency is improved as compared to the conventional single-symbol observation interval, without significantly increasing the receiver complexity. Performance bounds on the bit error probability are derived, by defining a set of characteristic distances for CPM signals and showing that TC-CPM is equivalent to a TCM scheme. Our results show that, with the same observation length, the proposed receiver is less than 0.5 dB inferior to the coherent receiver for which perfect channel information is needed. We also conclude that in terms of joint power-bandwidth-complexity, 2RC is the best candidate for rate-1/2 TCM codes