Wireless Communication Case Study

CHAPTER-1

INTRODUCTION

1.1 Introduction of Wireless communication

Pursuance for better ways of living has been instrumental in advancing human civilization. The communication services available at any time and place free people from the limitation of being attached to fixed devices. Nowadays, thanks to the remarkable progress in wireless technology, affordable wireless communication service has become a reality. Mobile phones hook people up whenever and wherever they want. Digital audio and video broadcasting offers consumers high-resolution, better-quality and even interactive programmers. The devices are now thin, light, small and inexpensive. Furthermore, smart mobile phones capable of multimedia and broadband internet access are showing

In this case, the signals on each subcarrier can be easily detected by a one-tap frequency domain equalizer (FDE). In cases where a short CP is inserted for increasing bandwidth efficiency, or because of some unforeseen channel behavior, the effect of frequency-selective fading cannot be completely eliminated, and inter carrier interference (ICI) and inter symbol interference (ISI) will be introduced. In this case, the signals on each subcarrier can be easily detected by a one-tap time domain equalizer (TDE). Equalization techniques are thus important in MIMO-OFDMA

In this probabilistic approach certain schemes have been proposed by researchers. These include clipping method, coding and signal scrambling method. Under the heading of signal scrambling techniques there are two schemes included. Which are Partial transmit sequence (PTS) and Selected Mapping (SLM). Although some techniques of PAPR reduction have been summarize, it is still indeed needed to give a comprehensive review including some motivations of PAPR reductions [4], to compare some typical methods of PAPR reduction through theoretical analysis and simulation results directly, and such as power saving. An effective PAPR reduction technique should be given the best trade-off between the capacity of data rate loss, PAPR reduction and transmission power, implementation complexity and Bit-Error-Ratio performance.

1.6 Objective

In this thesis MIMO-OFDM system is simulated over Rayleigh Fading channel using 64-QAM modulation technique. The main objective of the thesis is to reduce both Peak to Average Power Ratio & Bit Error Rate in MIMO-OFDM system simultaneously using a single scheme with the use of Alamouti based MIMO scheme and Low Density Parity Check code. 1.7 Organization