D-AMPS performance in PCS bands with array processing

Cellular systems that are upbanded from 800 MHz to 1900 MHz for PCS deployment will have to contend with additional path loss (6-7 dB), and faster fading, in addition to time dispersion and co-channel interference. On the downlink, additional power can be used to compensate for the path loss. On the uplink, increasing the power output from the hand portable is not possible from regulatory and battery life considerations. Faster fading further complicates adaptive equalization as well as adaptive interference mitigation techniques. For the digital-AMPS (D-AMPS or IS-136) standard, these impairments can be overcome through a combination of array processing and adaptive equalization using MLSE techniques.