Study On Receiver Algorithm Of Bit-interleaved Coded Modulation Iterative Decoding System

Bit-Interleaved Coded Modulation iterative decoding (BICM_ID) was proposed based on Trellis Coded Modulation (TCM). It is not only in the AWGN channel and Rayleigh channel can achieve a reliable transmission. Motivated by its low complexity, strong agility, high spectrum efficiency, and excellent performance, bit-interleaved coded modulation with iterative decoding (BICM_ID) has been a key technique of next generation of wireless communication. The research on the modulator of BICM_ID and bit-interleaved space-time coded modulation with iterative decoding (BI-STCM-ID), which combines BICM-ID with multi-antennas and space-time codes, mainly focuses on FEC, bit interleaver, and labeling maps etc., and the design of the corresponding demodulator includes joint iterative equalization and decoding, soft in soft out (SISO) demapper etc. There are still many problems to be resolved, such as optimized labeling mapper, low-complexity SISO demapper etc. So we try to get some improvement in these fields. The main content is displayed as follows.1) Analysised and summaried the structures, principles and technical characteristics of the BICM_ID system. On this basis, analysised the basic modulation and demodulation programs and comparised the performance border. And it is used for the design of the system.2) After analysised the basic principles and the performance of the SSD technology and the BICM_ID system's deficiencies, construct a program combined SSD and the BICM_ID.Starting from the diagram, the paper had a deep research on its key technology.3) To optimizing the design of the receiving part, the paper researched the iteratice decoding algorithm. To optimize the algorithm on the aim of reduce the complexity and improve the system performance. Choose a suitable iterative decoding algorithm, without reducing system performance under the premise of reducing decoder complexity.4) Studied the demodulation algorithm of the BICM_ID system. Analysis and comparison of the VGA (vector Gaussian approximation), SGA (scalar Gaussian approximation) and the MMSE (Minimum mean square error) algorithm's performance.5) By setting different system parameters, using different detection algorithms and different number of antennas, analysis and simulation the performance of BICM_ID_SSD system.