An adaptive antenna selection scheme for hybrid diversity combining

Antenna diversity has long been one method of increasing gains and enhancing performance in wireless systems. Such diversity provides a means to overcome the effects of signal multipath and fading in realistic RF channels or propagation environments. The design proposed here uses hybrid combining of two types of antenna diversity, spatial and polarization, to provide a consistently better received RF signal. The design is adaptive in that it periodically tests signal strength on a number of channels, and selects those which provide the best signals at that time. With a four-choose-two system, about 5 dB in power gain over the reference non-hybrid system is achieved. A significant reduction in signal power variance (about 2.3 dB) was also observed experimentally.