ÇOKLU KAFES KODLAMALI MODÜLASYONUN TOPLANABÝLÝR BEYAZ GAUSS GÜRÜLTÜLÜ KANAL VE YAVAÞ SÖNÜMLÜ RÝCÝAN KANAL ÝÇÝN PERFORMANS ANALÝZÝ

Bu çalýþmada, sistem performansýný arttýrmanýn bir yolu olarak literatürde bulunan çoklu kafes kodlamalý modülasyon (MTCM) tanýtýlmýþtýr. MTCM sistemi, sistemin band geniþliðini ve karmaþýklýðýný arttýrmaksýzýn, karþýlýðý olan TCM sisteminden daha iyi performans saðlar. Bu, 1/2 oranlý TCM ve 2/4 oranlý MTCM þemalarý örnek verilerek gösterilmiþtir. AWGN ve yavaþ sönümlü Rician haberleþme kanallarý üzerinden iletildikleri kabul edilerek bit hata olasýlýklarýnýn üst sýnýrlarýný veren eþitlikler deðerlendirilmiþtir. Bu eþitlikler kullanýlarak bit hata olasýlýklarýnýn üst sýnýrlarý Eb/N0’ýn fonksiyonu olarak çizilip karþýlaþtýrma yapýlmýþtýr. Karþýlaþtýrma her iki durumda da 2/4 oranlý MTCM þemasýnýn bit hata olasýlýðý üst sýnýrýnýn 1/2 oranlý TCM þemasýnýnkinden daha düþük olduðunu göstermektedir.

PERFORMANCE ANALYSIS OF MULTIPLE TRELLIS CODED MODULATION FOR AWGN CHANNEL AND SLOWLY FADING CHANNEL

In this work, we study briefly on the multiple trellis coded modulation (MTCM) which is found in literature as a way of increasing the performance of the system. An MTCM system provides better performance than a TCM counterpart without increasing the bandwidth and complexity of the system. This is illustrated by giving the rate 1/2 trellis coded modulation (TCM) and the rate 2/4 MTCM schemes as examples. Equations of upper bounds on their bit error probabilities are evaluated by assuming that they are transmitted over an AWGN and a slowly fading Rician communication channels. A comparison is made by plotting upper bounds of bit error probabilities as functions of Eb/N0. by using these equations. The comparison yields that the upper bound on the bit error probability of the rate 2/4 MTCM scheme is lower than that of the rate 1/2 TCM scheme for both cases.