8.1 Introduction

At present wireline and cellular systems are suffering from a capacity and bandwidth crunch due to various economic, legal, and political causes [1, 2]. The delay in the deployment of 3G systems makes the situation even worse. Various technologies are being developed to fill the void of "last mile/hotspot" coverage based on fixed broadband wireless technology. These networks are typically configured in a cell-based point-to-multipoint topology. The deployment of these networks requires a high initial up-front investment to pay for base stations and backbone networks. Additionally, a significant number of potential subscribers may not be reached due to LOS constraints. This chapter proposes a solution based on OFDM wireless communication techniques to resolve the issue of coverage and capacity. The solution is based on proven technology and an offshoot of existing standards so that it is cost-effective to implement without much of an upfront cost in engineering and production. The proposal utilizes the existing IEEE 802.16 standard for WirelessMAN MAC and higher-layer interfaces to minimize non-PHY development costs [1-34].

The IEEE standards committee has recently standardized the IEEE 802.16 WirelessMAN air interface based on OFDM techniques to serve the needs of the BWA scheme primarily to build a metropolitan point-to-multipoint communications infrastructure. The air interface is designed to carry any type of data or multimedia traffic with full QoS support. The MAC supports burst FDD and TDD in a consistent framework. The application of OFDM technology in wireless applications has continued to grow and has become the forerunner...