Predicting Outdoor Angular Characteristics and Power Distribution of Wireless LAN Signal Leaking from an Office Building

In this paper we predict angular characteristics of indoor-to-outdoor radio wave propagation and a probability density function of signal power leaking from an office building at 2442 MHz and 5200 MHz for a wireless LAN access point by using a large-scale electromagnetic field simulation based on the FDTD method. A numerical model of office building taking detail the floor plan and layouts into account is prepared for calculations. We evaluate the received signal strength indication on an outdoor observation surface which is spaced apart from the access point by a constant distance. The signal power distribution composes of several parts depending upon the azimuth angles measured from the wireless LAN access point. Each of them can be modelled by a Gaussian distribution if the path loss exponents are assumed to be constant in each angular region. Hence, the probability density function of signal leaking from the office building can be accurately predicted with a Gaussian mixture distribution.