Self-Adaptive Unequal Error Protection Algorithm Based On Prioritized LT Code

The popularity of wireless communication technology grows day by day. When an individual or a group sends and receives documents, they are requiring higher quality and efficiency. However, the bad radio channel situation for wireless communication presents problems for us. Fountain code, which performance well at the Binary Erasure Channel(BEC), is a kind of sparse matrix code. The LT code, a kind of fountain codes, is a typical pattern has superior properties. It plays a good performance under various of situations. Unequal error protection (UEP) is to improve the transmission efficiency to the maximum extent of source coding, which has been widely used in joint communication channel source methods.This paper firstly work on the joint source-channel coding knowledge and unequal error protection coding ideas. Several joint source-channel coding methods will be introduced. Article will focus on the unequal error protection method based on wavelet transform. Wavelet transform can analyze the signal in multi-scale analysis, for frequency analysis is often used in the field of information, signal processing, image processing and other aspects for its superior performance. Then this paper will mention a way to join these two algorithms, and will try to work out a way to improve the degree distribution function for the UEP method.What’s more, this article will describe the coding principle of LT codes, LT codes degree distribution function and the application of LT codes. Because of the distribution function always determine the key parameters of various types of fountain coding performance, we will focus on the design of degree distribution function of LT codes. Distribution function optimization design will bring better coding gain. On this basis, the article proposed an improved degree distribution function to achieve the unequal protection algorithm according to the different importance degree of the source code. Meanwhile, this paper suggest an adaptive system that designed for some practical application scenarios demand. After simulation and theoretical validation, the proposed method can indeed improve the quality and efficiency of coded transmission under poor channel conditions, and can give important information section priority during the protection.This paper can be divided into four sections, corresponding to the research focus mentioned above. Simulation are done with MATLAB.