Statistical characteristics of pedestrian-induced fading for a narrowband 2.45 GHz indoor channel

This paper presents a statistical analysis of pedestrian-induced fading for a narrowband indoor 2.45 GHz point-to-point link. A hybrid image/ray-shooting propagation simulator, capable of including the presence of moving human bodies within the environment, was used to investigate temporal fading for this channel. The traffic conditions were moderate, with 4 pedestrians moving in a regular fashion within a 150 m² open-plan office. Analysis of a 13-s period of movement indicated that the channel was Rayleigh distributed during pedestrian-induced fading. As the channel is narrowband, the fading is flat across the transmission bandwidth and slow compared to the symbol duration. The resulting impairment in transmission quality for DPSK modulation on an AWGN channel was determined: an additional 27-dB margin is required to operate at a BER of 10^-4 with respect to a non-fading AWGN channel. Frequency-selective effects were also investigated. The simulation was repeated for both faded (2.465 GHz) and un-faded (2.400 GHz) frequencies. Here the additional ray paths created by movement were capable of significantly improving the propagation conditions for the faded frequency