Performance Analysis Of Low Density Parity Check (LDPC) Encoded Cooperative Communication System With Implementation Of Orthogonal Frequency Division Multiplexing

摘要

Cooperative communication is a new paradigm that draws from the ideas of using the broadcast nature of the wireless channel to make communicating nodes help each other, of implementing the communication process in distributive fashion. Due to the requirement of ubiquitous coverage for wireless broadband services, demand for high data rate is increasing rapidly for the future wireless generations. More base stations are needed to deliver these services, in order to cope with the increased capacity demand and inherent unreliable nature of wireless medium. Usually wireless communication performance is badly affected by channel fading, noise, attenuation, crosstalk, less signal quality etc. This paper presents performance analysis and comparison of a three node cooperative communication system with orthogonal frequency division multiplexing (OFDM) and low-density parity check matrix (LDPC) encoded system. The simulation results show that the system performance can be improved by using cooperative communication techniques even when the inter-user channel is not good. The performance metric used for analysis is BER at a particular direct link SNR. In this thesis work we examine the performance of a cooperative communication system and its ability to realize the advantages and the ideas behind its invention. We model a simple amplify and forward, decode and forward repletion based cooperative communication system. To evaluate the performance of cooperative communication system using computer simulation. We focus on Bit Error Rate (BER) performance analysis of cooperative communication system with either an amplify-and-forward (AF) and decode-and-forward (DF) cooperation protocol using MATLAB. Our results shown that a better performance of a communication system could be achieved by allowing wireless network partners to communicate cooperatively.