Effect of cyclic prefix on data rates in WiMAX system with variation in delay vector, gain vector, signal to noise ratio and coding rates for different modulation techniques

In WiMAX technology: orthogonal Frequency Multiplexing (OFDM) can provide large data rates with sufficient robustness to multipath fading. A guard time, in the form of cyclic prefix (CP) is inserted between OFDM symbols to eliminate both the inter-symbol interference (lSI) and the inter-channel interference (ICI). This paper aims to implement a WiMAX system using Simulink of MATLAB. The simulation is used to study the effect of the cyclic prefix on the bit error rate (BER) with different types of modulation techniques (BPSK, 4QAM, 16QAM, and 64QAM) based on the variation in gain vector, delay vector, and signal to noise ratio (SNR). The simulation results of all cases are compared to specified the values of cyclic prefix, gain vector, delay vector, and modulation technique that give the lowest values of BER. Based on these values the performance evaluation of WiMAX communication is done.

I. Introduction

WiMax is a wireless broadband technology based on IEEE 802.16 standard; This system is based on the Orthogonal Frequency Division Multiplexing (OFDM) and realized broadband data transmission by using a radio-frequency range of 2–11 GHz and 10–66 GHz. WiMax system is a telecommunications technology which enables wireless transmission of voice and data and provide wireless access[1].