Abstract :
The unique characteristics of wireless in-building network (WIN) systems based on microwave radio technology are addressed, focusing on the multipath propagation problem which most distinguishes radio from wired LAN media. This is followed by a discussion of the three principal techniques that have been developed within the radio communication industry to deal with this multipath problem: adaptive equalization, spread spectrum, and antenna diversity. A review of the strengths and weaknesses of each of these techniques reveals that antenna diversity is clearly the preferred choice for use in WIN systems operating in the recently allocated spectrum near 18 GHz. An example of such an antenna system is examined. It is shown how these multiple, directional antenna systems function in three types of environment.<>
Keywords :
cellular radio; directive antennas; diversity reception; local area networks; microwave links; radio networks; radiowave propagation; spread spectrum communication; 18 GHz; SHF; adaptive equalization; antenna diversity; antimultipath techniques; directional antenna systems; microcells; microwave radio technology; multipath propagation; radio communication industry; radiowave propagation; spread spectrum; wireless LAN; wireless in-building network; Adaptive arrays; Adaptive equalizers; Communication industry; Local area networks; Microwave propagation; Microwave technology; Radio communication; Radio propagation; Spread spectrum communication; Wireless LAN;
