Empirical Mode Decomposition Based Two-Way Hybrid Decode Amplify and Forward Cooperative Relaying Protocol

Abstract

In the recent year, wireless communication system has experienced a tremendous growth and happened to be one of the most active areas of technology that covers all aspects of everyday life. However, the system is characterized with multipath fading resulting in variability of the received signal that affect overall system performance. Existing Hybrid Decode Amplify and Forward (HDAF) cooperative relaying protocol used to address the problem suffers from signal outage and fluctuation in the amplitude of the received signal at the destination. Hence, in this study, two-way HDAF (2-HDAF) cooperative relaying protocol is proposed using Empirical Mode Decomposition (EMD) and angular beamforming technique. The multiple copies of the transmitted signals were decoded at the relay node by selecting signal that is greater than the set threshold of 2.5dB. The decoded signal was amplified by multiplying with the relay gain. However, if the channel between the source and relay is corrupted and relay cannot decode the received signal, the received signal was made to pass through EMD technique to attenuate the noise that might present before signal amplification. The amplified signal was beamformed using angular beamforming and propagated to the destination during second hop transmission. The proposed technique is evaluated using TP and BER by comparing with the existing HDAF technique. The proposed EMD-2HDAF gave better performance with 67.3% reduction in BER and 42.34% increase in TP. The proposed technique can be deployed to improve the performance of cooperative diversity in wireless communication system.