Angle diversity at 6 GHz: methods of alignment and test results

A synopsis is presented of performance data for a single aperture dual beam antenna operating with a 6 GHz 135 Mb/s 64-QAM digital microwave system. Three tests, spanning 19 months of operation, with over 2.67 million seconds (742 hours) of clear-air fading greater than 10 dB, are described. The general conclusion is that angle diversity shows promise for paths with a history of pure multipath problems and locations where space diversity is impractical or impossible. However, angle diversity should not be looked upon as a cure-all for propagation problems, and caution should be used in selecting paths to be equipped with angle diversity. An understanding of the prevalent fade mechanisms to be encountered is necessary to correctly apply single aperture dual beam antennas