New Methods to Reduce Turbo Decoding Latency and the Complexity of Bit Insertion Techniques
Mohammed AlMahamdy · OhioLink ETD Center (Ohio Library and Information Network) · 2017
The turbo code has been adopted in many cutting-edge systems for its outstanding error correcting performance.Since its invention in the early 90s, researchers have been working to improve and optimize its performance.Among these efforts, the reduction of the decoding latency and the improvement of the BER performance are the scope of interest in this dissertation.Early stopping (ES) rules are deployed within the turbo receivers to reduce decoding latency and save resources.The aim of these rules is the reduction of the average number of iterations at a tolerable performance degradation.They monitor the generated output along the iterations to terminate the loop once the output reaches a satisfactory level of reliability.In this dissertation, the researcher proposes two novel ES methods to improve the performance of previous methods.The first method optimizes the operation of almost any conventional ES method.It is the norm among the published ES methods to be applied after the output of the second decoder becomes available.The proposal is to execute almost any ES check twice per iteration instead of once.This increases the chance of catching the convergence point sooner.The second method presented in this dissertation is designed to target the "undecodable" blocks for early termination.This method is designed to be incorporated with any other early terminating method that works with the converging