Field tests designed to demonstrate increased spectral efficiency for personal communications

Field tests were conducted to test whether a broadband code division multiple access (CDMA) network can be overlayed on the 1850-1990-MHz band which will not interfere with existing FSM (fixed site microwave) users of that band and will itself function properly. The test demonstrated that, on the average, even without the use of a notch filter and without voice activity, there will be no significant interference to microwave receivers under EIA specification 10E when 50 users are located in single cells of diameter 1200 ft. The CDMA system functioned with excellent voice quality at mobile power levels of 100 μW or less, and the microwave signals caused no significant effect on performance. Additionally, the tests obtained data on propagation conditions in the 1850-1990-MHz band in urban, rural, suburban and in-building areas