A wireless local loop system based on wideband CDMA technology

This article describes a wireless local loop system based on wideband CDMA technology. The unique features of CDMA technology make it a formidable alt ernative for fixed wireless telephone applications. The VV-CDMA technology used by this WLL system is selected to provide primarily ISDN-like services and data rates to subscribers. This technology also provides a smooth tran sition into the third generation wireless technology. The air interface use d in this WLL system is an interim TTA standard, which specifies a CDMA-bas ed protocol operating in the 2.30-2.40 GHz band. The standard allows two ty pes of bandwidth (5 and 10 MHz). The WLL system described in this article i ncludes the WLL gateway switch, the radio port controller and the radio int erface unit. The gateway switch connects the radio system to the PSTN and I SDN. The RPC provides concentration and control functions to a number of ba se stations called RPs. The RIU is comprised of the fixed units attached to the residential or commercial buildings. Also included are the radio port operation and maintenance (RPOM) unit, which is responsible for maintaining and managing the radio network elements, and the interworking function uni t, which is used as a gateway to data services such as the Internet and PSP DN.