DIGITAL RADIO PROPAGATION EXPERIMENTS AT 6 GHz PART Ⅱ

摘要

Tne principal objectives of this propagation testing program are threefold: First, to understand the physical and meteorological causes of multipath. Second, to measure the quantity and basic characteristics of muItipath propagation on a reasonably active path,and thirdly, to measure the effects of multipath conditions on various receiver configurations and evaluate multipath countermeasure techniques.Results are presented for a 226 day test period of which 75 days had multipath fading greater than 10 dB. Data is presented for five receiver configurations measured simultaneously during multipath propagation conditions.It is concluded that a 90 Mbit digital microwave system operating on a reasonably well designed path which employees space diversity receivers and baseband data switches can meet long haul outage objectives, even if the path has significant amounts of multipath fading.