Handover criteria for city microcellular radio systems

1700 MHz attenuation and bit error rate (BER) measurements were conducted at the center of a major urban area in southern England in order to compile a radio propagation and BER database for handover criteria study in city microcellular radio systems. The focus of the experiments was to provide realistic data for handover simulation in typical city microcell environments, thus minimizing inaccuracies due to the inadequacies in propagation modeling. Results revealed the path loss followed the inverse third to fourth power law in majority of the cases using simple regression fitting. The short-term signal fading statistics varied with Rice factors in excess of ten down to zero, as the distance between the mobile unit and the microcellular base station increased. Computer simulation indicated that both RSSI (received signal strength indicator) and BER could be used as handover criteria. The optimal threshold level for handover request, however, differed from location to location