An Improved Method for the Convergence of Iterative Detection in SCCC System

Concatenated coding schemes with interleavers consist of a combination of two simple constituent encoders and an interleaver. The parallel concatenation known as "turbo code" has been shown to yield remarkable coding gains close to theoretical limits, yet admitting a relatively simple iterative decoding technique. Serially concatenated convolutional code (SCCC) proposed by S.Benedetto may offer performance superior to that of turbo codes. In order to solve the problem of positive feedback during iterative detection of short data frame SCCC system, a method based on weighed extrinsic information exchange is proposed. Theoretic analysis and simulation results in additive white Gaussian noise (AWGN) show that the proposed method can prevent the phenomena of positive feedback from taking place, reduce the error floor, and improve the convergence of iterative detection and the performance of bit error rate (BER).