Research On Soft Decision Decoding Of RS Code

Joint Tactical Information Distribution System (JTIDS) is a kind of information distribution system with big capacity,security,anti-jamming and of time division multiple address. It has integrated the capabilities including the communication,the navigation and the recognition. It also can offer the service to armed forces unity. The system of this paper based on the JTIDS system, which was directed against air to ground. Nowadays encoding and decoding methods are widely used in communication and computer territories. Among these, RS is one of the most outstanding methods. So the RS code is used in this system to satisfy the requirement of channel reliability.Firstly, this paper deals with RS code's encoding/decoding principle, particularly describes the method of soft-decision decoding of RS code. Soft-decision decoding can make use of the output information, and substantial coding gain can be gotten, which has been observed early. Since soft-decision decoding needs much more computation, it is so complex as to be infeasible in many applications. Though some soft-decision algorithms used in binary finite field have existed, non-binary is seldom concerned. An algorithm for soft-decision decoding RS (15, 9) is presented, which refers to the generalized minimum distance (GMD) decoding algorithms. And it gives an improved algorithm, which developed for the fast GMD decoding of RS codes. Finally, we give its hardware implementation, a TDM technique based on Modified Euclidean iterative algorithm and fast GMD iterative algorithm are proposed, meanwhile, the Chian search progress has been improved in this paper.