Turbo Trellis Coded Modulation (TTCM) with Imperfect Phase Reference

ABSTRACT In this paper, we investigate the performance of Turbo Trellis Coded Modulation (TTCM) over AWGN, and Rician channels and assume that phase disturbance is available. As we know Turbo Trellis Coded Modulation (TTCM) is similer to binary turbo codes, but employs Trellis Coded Modulation (TCM) codes which include multi-dimensional codes. The combination of turbo codes with trellis codes leads to a strigthforward encoder structure, and allows iterative decoding as binary turbo decoder. However, iterative Turbo Decoder needs to be adapted to the decoding of TCM codes. Here, we investigate TTCM for 8PSK for several Rician parameter K and effective signal-to-noise ratio in the carrier tracking loop a. Thus, our results will reflect the degredations both due to the effects of the fading on the amplitude of the received signal and of a noisy carrier reference. Keywords- Turbo Trellis Coded Modulation, Rician Channel, Imperfect Phase Reference OZET Bu makalede Turbo Kafes KodlamalA½ (TKK) sistemlerin AWGN ve Rician ortamlarda faz bozulmasA½ durumunda hata baA¾arA½mA½ elde edilmiA¾tir. TKK yapA½sA½ ikili Turbo modulasyonu gibidir ancak TKK cok boyutludur. Turbo kodlamanA½n Kafes Kodlama ile birlikte kulanA½mA½ kodlayA½cA½ yapA½sA½nA½n deA°iA¾imini gerektirir. AlA½cA½da ise ikili kodlayA½cA½larda olduA°u gibi iteratif kod cozucu yapA½sA½ vardA½r. Burada 8PSK modulasyonda TKK farklA½ Rician katsayA½sA½ K, faz bozulma katsayA½sA½ a icin benzetim sonuclarA½ elde edilmiA¾tir. Elde edilen sonuclar hem genlikte hem de faz daki bozulmayA½ icermektedir. Anahtar Kelimeler: Turbo Kafes Kodlama, Rician Kanal, Faz BozulmasA½