Adaptive modulation coding in MIMO-OFDM for WiMAX using GNU Radio

Abstract

Mobile WiMAX is a broadband wireless access based on OFDM/OFDMA technology which employs Adaptive Modulation and Coding (AMC) scheme to attain higher data rates. In this paper, a selection strategy is incorporated with GNU Radio for the determination of Modulation and Coding Scheme (MCS) level dependent upon channel estimation parameter over AWGN and Rayleigh fading channels. MCS level choice has been done for different threshold values by varying channel model and FFT size. BER (Bit Error Rate) execution of WiMAX physical layer is investigated utilizing Convolutional coder, RMG (Reed-Muller-Golay) coder and RM (Reed-Muller) coders over AWGN and Binary Symmetric Channels by changing number of bits for every byte and modulation schemes in GNU Radio Companion. In this paper, various 2x2 MIMO frameworks are analysed under digital modulations and Convolutional code rates. The aim of this paper is to provide a thought about the benefits of multiple antenna systems over single antenna systems deployments using GNU Radio. keywords- AMC, GNU Radio, MIMO, OFDM, STBC, WiMAX.