Assessment of base station antenna diversity efficiency in frequency selective μ- and pico-cell environments

A large measurement campaign is performed in both in- and outdoor environments, covering μ- and pico-cells. A dual-correlation sounder with 40-MHz chip rate at 1845 MHz is used for simultaneous recording of two diversity channels. It is shown that compact space diversity antenna systems will provide worthwhile diversity gain in the considered environments. Only a modest degradation in diversity power gain is found between the up- and downlink situations for a time division-duplex (TDD) system, thus providing comparable power link improvement at both base and mobile with base station diversity alone. The instantaneous frequency selective fading fluctuates very fast. Thus, the diversity dispersion suppression in the uplink is limited when using base station diversity