Chapter 2 Propagation Fundamentals & Literature Search

The performance of wireless communication systems depends on the radio wave transmission path between the transmitter and the receiver. Unlike wired channels that are stationary and predictable, radio channels are extremely random. In addition, electromagnetic wave propagation characteristics vary significantly over different frequency bands. Therefore it is vital to thoroughly understand the propagation characteristics and develop a channel model for the proposed wireless communication system before site-specific planning and deployment can be initiated. This chapter introduces radio propagation mechanisms and principles, primarily for LMDS applications. Impairments to the radio propagation, path loss model and small-scale fading effects are discussed. Issues pertaining to propagation of millimeter waves are also presented. Finally, the chapter elaborates on the effects of rain on radio wave propagation. The concepts and models presented are essential for understanding propagation measurements and results in Chapters 3 through 5 of this dissertation.