Path loss and multipath delay statistics in four European cities for 900 MHz cellular and microcellular communications

摘要

Typical and worst case channel path loss, RMS delay spreads, and excess delay spreads (10 dB down) at 900 MHz in four European cities using typical cellular and microcellular antenna locations are presented. It is shown that a change in reference distance from 1 km to 100 m can change the perceived propagation power law exponent from 3.0 to 2.7, where free space propagation is assumed from the transmitter to the reference distance. This is a significant result, since the path loss directly affects the frequency reuse efficiency in CDMA spread spectrum systems. Measured data show that for microcellular sites, RMS delay spreads are less than 2 mu s, with excess delay spreads (10 dB) less than 6 mu s. At typical cellular locations with high base antennas, RMS delay spreads are generally less than 8 mu s and excess delay spreads (10 dB) are less than 16 mu s. Worst case measurements resulted in a RMS delay spread of 19.6 mu s and an excess delay spread of 51.3 mu s.