Attenuation of 400 MHz signal in a metropolitan city

A theoretical model for studying the behavior of incoming UHF signals at various spots in regions containing numerous physical structures (i.e. hills and buildings) is presented. The model accounts for losses of the transmitted signal strength due to diffraction/reflection from the structures. The theoretically calculated values of the received field strength are compared with the experimentally observed values at various measuring spots, and a close agreement between the two is found. The experimental results show that in a quasismooth terrain (where there are no obstacles) the received field strengths are as high as 142-120 dBμV/m, whereas at points surrounded by hills and high-rise buildings, the received field strengths are of the order of 85-67 dBμV/m and 90-40 dBμV/m, respectively