Local Multipoint Distribution Services (LMDS) system concepts and implementation

The Federal Communications Commission (FCC) has allocated spectrum for a new type of communications service called the Local Multipoint Distribution Service (LMDS). The Canadian government has also set aside frequencies for a similar service called Local Multipoint Communication Systems or LMCS. Both provide for approximately 1 GHz of bandwidth in the 28 GHz band. This spectrum will be auctioned to a single licensee for a Basic Trading Area (BTA) in the United States. There are 493 such BTAs in the US. The license holder can transmit video, voice, data and/or any combination of these in one-way or two-way systems using analog or digital techniques. TI's brand name for hardware and software designed to serve the LMDS/LMCS market is MulTIpoint/sup TM/. It is based on a cellular arrangement of nodes which provide broadband two-way wireless communications to subscribers located within a few kilometers of the nodes. The nodes are connected into the network via fiber optic cable. The system provides transmission of video, voice and data to a combination of business and residential customers alike. Although MulTIpoint/sup TM/ is being developed with basic technology today, next generation hardware will need to provide improved performance at lower costs. One way to achieve this is to implement many functions using digital signal processing. This paper highlights areas which are being considered for such implementation.