METHOD AND APPARATUS FOR CORDLESS INFRARED COMMUNICATION

摘要

A method and apparatus for communicating from a base unit (40) to a plurality of portable infrared devices (48.1-48.8) are described using established communication protocols. The signals are sent along cables from the base unit via stationary infrared receiver/transmitter (RT, 46.1-46.16) modules at infrared carriers in standard transmission and receiving slots to and from the portable devices. The RT modules are distributed throughout a space in the building. Control circuits are used to assure that different infrared carrier signals, originating from nearby RT modules, arrive at any one portable device with a phase difference that does not exceed an acceptable amount. The system also includes circuitry in the base unit to select the best infrared signal detected by several RT modules from any one particular portable device. A hub is described to expand the number of RT modules with which a base unit can communicate.