Method for decoding tail-biting convolutional codes

Abstract

A method for decoding tail-biting convolutional codes is disclosed. In the method, all beginning states of a trellis diagram are initialized. Forward Viterbi metrics are calculated for the trellis diagram. A trace-back process is performed from an ending state of the trellis diagram at a first time instance to a first state where all surviving paths converge at a second time instance. Backward Viterbi metrics are calculated for a predetermined period of time from the first state at the second time instance to a second state at a third time instance. A trace-back process is performed from a designated state, which is equal to the second state, at the first time instance to determine a most likely path for the convolutional codes in the trellis diagram.

Description

[0001] cross reference [0002] This application claims U.S. Patent Provisional Application No. 60 / 674,776, filed April 26, 2005, entitled "Low Complexity Decoding of Tail-Biting Convolution Codes," and filed April 21, 2006, entitled "Method for Decoding Tail-Biting Convolution Codes." Priority of U.S. Patent Nonprovisional Application for Biting Convolutional Codes. technical field [0003] The present invention relates generally to digital signal communications, and more particularly to methods for decoding tailbiting convolutional codes. Background technique [0004] Signals transmitted on a communication channel between a sender and a receiver may be affected by noise, or interfered with by adjacent channels. One purpose of channel coding and decoding is to protect signals from errors due to noise or interference. Convolutional codes have been widely used in digital communications in order to incorporate forward error correction into sent messages. figure 1 A typica...

AI Technical Summary

Problems solved by technology

However, the computation of tail bitcodes can be complicated because of the uncertainty of the start and end states

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