Distributed antenna in the radio local loop based on DECT

Abstract

The Digital European Cordless Telecommunication System (DECT) is gaining acceptance in environments different to the ones the system has been designed for. In particular in the radio local loop (RLL) and in personal communication services (PCS) applications. The main difference between indoors, where DECT was supposed to work, and outdoors is that in this latter environment the signal propagation is not limited between walls. The first result of this environment is the capacity limitation of the DECT base station (BS) due to interference. To increase the DECT system's capacity it is possible to use directional antennas in the BS and in the user terminal. Even using interference reduction techniques most of the blocked or interrupted calls are due to the co-channel interference, so the traffic capacity per BS is low compared to the amount of channels per base station. In this paper we show that it is possible to share BS equipment between several cells, increasing the usage of radio fixed part resources without reducing traffic capacity. From the interference point of view the capacity of those split BS is identical to the former solution but thanks to the shared use of several antennas the efficiency is higher.