In this paper, an interference analysis method with a site-specific path loss model for a wireless personal area network (WPAN) is proposed. The site-specific path loss model is based on geometrical optics and geometric probability to consider both site-specific radio propagation characteristics and a closed-form expression to obtain the mean interference from which the uniformly distributed multiple interferers are derived. Therefore, the proposed interference analysis method can achieve more computational simplicity than the Monte-Carlo (MC) simulation, which uses the ray-tracing (RT) technique. In addition, better accuracy than the conventional interference analysis model that uses stochastic method can also be achieved. To evaluate the proposed method, a signal to the interference-noise ratio with a mean interference concept for uniformly distributed interferers is calculated and compared in two simulation scenarios. As a result, the proposed method produces not only better matched results with the MC simulation using the RT technique than the conventional interference analysis model, but also simpler and faster calculation, which is due to the site-specific path loss model and closed-form expression for interference calculation.
Ⅰ. IntroductionAs the demand for wireless communication services for indoor environments to provide multi-function and high data rate increase, more and more electrical devices short-range radio interfaces such as ultra-wideband (UWB), Zigbee, and Bluetooth are developed. These wireless communication technologies are standardized in the IEEE 802. 15 task group for wireless personal area networks (WPAN) [1]. In addition, a wireless sensor network is composed by these applications for each service target. However, because these applications generally utilize common unlicensed industrial, scientific, and medical (ISM) bands, they have difficulty in controlling the co- Fig. 1. Geometry of interference model. mmunication services for multi-users. Therefore, these applications can interfere with each other because they tend to be located in close proximity. In addition, UWB techniques, which are considered a means of supporting a high data rate, reuse the existing radio spectrum so that UWB systems can generate interference with other radio communication systems. For these reasons, many studies on the coexistence of different communication systems in WPAN applications or wireless local area network (W-LAN) applications have been done [2~4].The methods of analyzing interference effects are categorized into minimum coupling loss (MCL), enhanced MCL (E-MCL), and the Monte-Carlo (MC) based method. The E-MCL method is also known as the stochastic method; it assumes that interferers are uniformly distributed in an interference zone as shown in Fig. 1. In this method, the path loss is calculated by the simple and empirical path loss model with path loss exponents for indoor environments. Conventional interference analysis is performed mainly by this stochastic method. Although this meth...