Spectrum requirements of an indoor pico-cell radio system

Abstract

In this paper, the spectrum and power requirements of an indoor PiCO-Cell radio system at different operating fre- quencies in a building are studied. Based on measurement results obtained in other studies on losses due to walls, floors, etc., a pico- cell radio system with capability is considered for a typical high-rise office building. The amount of spectrum required by the pico-cell system is evaluated based on operating other by a spacing of 2 m. Then, for a given outage probability and the corresponding number of receiver points, we determine the transmitter effective radiated power (ERP) required to provide sufficient signal level to these receiver points. This is done for a one-, two-, three-, and four-cell configuration. The spectrum required for each floor is calculated based on frequency, base station locations and Cell configurations,-verticai reuse distance, outage probabilities, and floor layout, in addition to traffic demand and blocking probability. an assumed traffic level and blocking probability. The overall spectrum for the building can also be obtained Once the vertical reuse distance is known. I. INTRODUCTION T IS WELL-KNOWN that cellular radio systems with small I cells support more traffic than those with larger cells. This concept led to the introduction of micro-cellular systems in the early 1980s. These systems with cell radius in the order of 1 km or less have tremendous traffic carrying capability and have been proposed for outdoor personal communications. In recent years, the requirements of personal communica- tions in the indoor environment are also emerging. Because of the smaller coverage area and a lower power requirement, indoor systems are even smaller in size than micro-cellular systems. Pico-cell systems have cell radius in the order of tens of m and could provide much higher system capacity than cellular radio systems. The purpose of this paper is to study the spectrum and power requirements of such a pico-cell system when implemented in a high-rise office building. These requirements are dependent on a number of factors such as operating frequency, base sta- tion locations and cell configurations, vertical reuse distance, outage probabilities, and floor layout. Since the radio spectrum is scarce, it is necessary to operate the pico-cell system in the most spectrally efficient manner. Furthermore, spectrum at the upper frequency range is relatively more abundant, and hence more attractive for indoor radio applications. It is therefore worthwhile to study the impact of frequency on the spectrum requirement of a pico-cell system. 11. APPROACH In the analysis of the impact of the above factors on the spectrum and power requirements of an indoor radio system, the following approach is taken. First, the floor is represented by a number of receiver points which are separated from each