Mobile propagation loss and delay spread characteristics with a low base station antenna on an urban road

Propagation loss and delay spread were studied experimentally, in order to design digital mobile communication systems. For propagation loss, the results were as follows, (i) When there are no obstacles on the road, the distance over which a radio wave propagates with only free-space loss increases with frequency. (ii) When there are obstacles (trucks and buses). and when the base station antenna heights are 5 and 15 m. the loss in excess of the free-space loss is 15 and 10 dB, respectively, at 1 km, (iii) Frequency dependence of this excess loss is not significant. (iv) On a cross road. the loss increases rapidly traveling away from the intersection. For the delay spread. the results were as follows. (i) The delay spread increases slightly with distance (less than 0.3 mu s within 1 km). (ii) The standard deviation of the delay spread increases slightly with distance (less than 0.2 mu s). Using the above results. a service area that extends along the road on which the base station is located and is limited in distance along cross roads can be predicted.>