Interleaver Design Based On Linear Congruence

The emergence of Turbo codes is a milestone in the development history of the channel coding theory. With the performance of approaching the Shannon limit, turbo code has changed the people’s designing idea of the encoding method. The design method of channel coding has been changed from increasing the minimum hamming distance to reducing the number of low weight code word. Right now, how to improve the performance of Turbo codes is a hotspot of research on coded information industry. And the designing of interleaver is one of the numerous breaches.Interleaver Design has a significant impact for the systems performance of Turbo code. It affects directly the quality of encoding and decoding system performance. Different design strategy for interleaver reflects different performance in different coding environments. In order to get better performance, an appropriate strategy should be chose in the numerous interleaver design strategy. Based on the depth analysis of the interleaver’s role and principles, this article analyzes systematically and compared some typical interleavers. Improve appropriately the linear congruential interleavers, and proceed with the simulation analysis and theoretical studies.The paper mainly includes the following aspects for the linear congruential interleavers study:1. Analyze the basic components of Turbo Codes, and describes the main working mechanism of Turbo codes. Research the characteristics of Turbo codes encoding. Select the appropriate coding strategy for different coding environment.2. Research the working principle of encoding and decoding of Turbo codes. For several typical decoding algorithms, demonstrate the influence of the main parameters for Turbo code decoding by detailed analysis. Explore respectively the important part of Turbo code encoding and decoding system. Relate and analyze the characteristics of the different convolutional codes, and the select strategy of convolutional code under different coding environment.3. State the interleaver principles briefly. Introduce several commonly interleaver, zero processing and delete more processing in coding system. Introduce the two kind algorithms: MAP and Viterbi algorithm briefly. Compare the complexity and the application range of different decoding algorithm. Introduce the selection strategy of the decoding algorithm briefly.4. Detailed introduce several typical interleaves, and analyze their features. Discuss the properties and design principle of interleaver. Analyze and compare the advantages and disadvantages of different interleaver, and the selection strategy of different coding interleaver under the different environment.5. Mainly research the random interleaver, linear congruential interleavers. Build AWGN channel model on the software of MATLAB to implement the simulation experiment of random interleaver, linear congruential interleaver under certain coding environment.Explore the effects of the interleavers for Turbo codes.6. Improve the interleavers for the short frame data transmission based on insurance parity sequence. Process the data with the insurance parity sequence before the transfer sequence interleaving, which disorder the original data sequence. Analyze the characteristics and advantages of the interleaver for short frame data transmission with the simulation experience. Compare and analyze the impact of the three interleavers on the Turbo code performance according to the basic structure of the three interleavers. Discuss in detail the advantages and disadvantages of linear congruential interleaver and random interleaver. Analyze the feasibility with the simulation experience data. Prove that the improved interleaver has a better performance in the short frame data transmission. And it is easier to implement than the relatively random interleaver.