Coding Rates and MCS using Adaptive Modulation for WiMAX in OFDM Systems using GNU Radio

Various wireless technologies have been emerging with ever increasing demand for higher data rates along with low bit error rates (BER's). Adaptive modulation and coding (AMC) schemes, when incorporated into WiMAX helps the system to react dynamically to the channel variations thereby providing higher data rates and improve BER performance. Based on the channel state information, both the modulation and coding rates can be varied so as to achieve higher throughput and improve spectral efficiency. This work proposes an efficient adaptive modulation coding technique, which maximizes the throughput, while maintaining a target BER. It proposes to select a particular modulation coding scheme along with the corresponding coding rates based on the given threshold. The parameter values, such as SNR, BER, CINR, BLER channel attenuation factor, are accepted and then the modulation schemes with an appropriate coding rate are selected for the operation of a OFDM system in GNU Radio.