PERFORMANCE ANALYSIS OF TURBO CODES IN FADING ENVIRONMENTS

Abstract

Turbo codes belong to the class of convolutional error correcting codes used in wireless data transmission applications like mobile communications, deep-sea communications, satellite communications and other power constrained fields. Turbo Decoder consists of concatenation of decoders based on Maximum a posteriori algorithm. Turbo decoding is an iterative principle where the constituent decoders pass extrinsic information to each other with an interleaver or deinterleaver in between. The performance of turbo codes approaches the Shannon limit making them most sought after in current wireless applications. Simulations of Turbo code performance under different parameters and different situations like number of iterations, different encoder structures, interleaver types, puncturing has been done. The performance of turbo codes was simulated in Rayleigh and Rician fading channels. The turbo codes have shown a considerably remarkable performance with variations in parameters and environments.