Overview

This chapter will briefly discuss some of the more important issues associated with an antenna system regarding 3G applications. The selection of the antenna type to utilize for base station whether it is for a macro, micro, or pico cell is similar for all the technology platforms. There are of course some differences related to the different design issues associated with a 1G, 2G, 2.5G, or 3G system. The key difference in the antenna design issues lies in the desire to keep the systems either separate or unified depending on the underlying technology platform the new system is being overlaid upon.

The antenna system for any radio communication platform utilized is one of the most critical and least understood parts of the system. The antenna system is the interface between the radio system and the external environment. The antenna system can consist of a single antenna at the base station and one at the mobile or receiving station. Primarily the antenna is used by the base station site and the mobile for establishing and maintaining the communication link.

There are many types of antennas available, all of which perform specific functions depending on the application at hand. The type of antenna used by a system operator can be a collinear, log periodic, folded dipole, or yagi to mention a few. Coupled with the type of antenna is the notion of an active or passive antenna. The active antenna usually has some level of electronics associated with it to enhance...