Adaptive modulation and coding for efficient wireless channel capacity utilisation

Abstract

Wireless technologies seek to utilize the available channel bandwidth to the maximum but with less error in the data transmission. Channel conditions are mostly unstable, impacting negatively on the data it carries. Adaptive Modulation and Coding (AMC) has been adopted for use in technologies such as WiMAX and LTE to combat the effects of unstable channel conditions. Basically, the AMC technique began with the use of thresholds in the channel's Signal to Noise Ratio (SNR) to select the best fit Modulation and Coding Scheme (MCS) that will incur the least allowable errors and achieve the best data throughput. Over the years, there has been a lot of study in the enhancement of AMC systems in predicting the most current channel conditions. This work seeks to compare some channel path prediction methods. The work models Order-1 and Order-2 Markov models and compares with the threshold established using AMC. This work shows Order-2 Markov AMC as more spectrally efficient in mitigating the effects of fading under different wireless channel conditions such as, flat fading and dispersive fading channels. Copyright ISCA, CAINE 2014.