Modeling and analysis of time varying radio propagation channel for LMDS

This paper reports on the novel radio channel models based on measurements conducted in various environments such as urban, suburban and rural areas of Singapore for local multipoint distribution service (LMDS) system design. A generalised tapped delay line model was developed to represent the time varying complex channel impulse response. Also, a model for excess path loss due to various blockage conditions and the relationship between delay spread and environment loss were reported. The propagation characteristics obtained include total received signal, mean delay, RMS delay spread and various statistical characteristics such as cumulative distribution function, level crossing rate and average fade duration of the fading signal to study the system performance