An Improved Adaptive Modulation and Coding for Cross Layer Design in Wireless Networks

Abstract

Recent research in cross layer design focuses on a number of integration techniques with physical layer to maintain a strategic distance from the shortcomings of Open Systems Interconnect (OSI) layer and also to guarantee the Quality of Service (QoS) in heterogeneous systems. Amongst the integration techniques, the Rate-Adaptive Modulation and Coding draws more attention of the researchers. In this paper, an improved Adaptive Modulation and Coding (AMC) scheme for Cross layer approach has been proposed with slight modifications in the existing AMC scheme that considerably improves the spectral efficiency of the transmission framework for time varying channels. The existing AMC conspire uses the well-known modulation techniques like Binary Phase Shift Keying, Quadrature Phase Shift Keying and Quadrature Amplitude Modulation with different rates that yield low spectral efficiency. This paper presents an improved AMC with the Gaussian Minimum Shift Keying (GMSK) modulation that yields a spectral efficiency of 35% more than the traditional AMC. Proposed method also results in a maximum throughput of 20–50% more than the traditional AMC. The evaluation of performance metrics like Signal to Noise ratio and error rate clearly depicts that the proposed approach significantly outperforms the traditional AMC.