Performance Analysis of Symmetric and Asymmetric LTE Turbo Codes with Prioritisation and Regression Based Scaling

Abstract

Standards like Long Term Evolution (LTE) employ Turbo coded QAM systems in order to achieve high data rates. Despite the fact that several mechanisms have been proposed in order to enhance the error performance of Turbo coded QAM systems, there is still the need to come up with novel or hybrid systems which can contribute towards further improved error performances. In this paper, a comparative analysis has been performed between symmetric and asymmetric LTE Turbo codes with the incorporation of techniques such as prioritization and regression based extrinsic information scaling. Results demonstrate that significant enhancement in the error performance throughout the whole Eb/N0 range can be obtained with high order modulation when these techniques are used. With both symmetric and asymmetric LTE Turbo codes employing 64-QAM and a code-rate of 1/3, an average gain of 0.3 dB below BERs of 10−1 is obtained over symmetric and asymmetric LTE Turbo codes.