WIRELESS INFRARED FACTORY NETWORK FOR HAND-HELD TERMINALS

An experimental wireless infrared network with ISDN compatibility is described. This factory network has been studied in a European project: ''FCPN'' (Factory Customer Premises Network). The architecture of the network is a cellular one. Infrared cells are connected together by a high-speed optical fiber backbone. Hand-held terminals communicate via an infrared (IR) channel based on a diffusion technique. The communication protocol on the infrared channel is based on the ISDN protocol with standard ISDN rate (2 x 64 kbits/s + 16 kbits/s). Measurements of diffusion properties of standard construction materials are presented. These properties are in good agreement with the requirements of an indoor IR diffuse transmission. Architectural choices for the IR transceiver are discussed with special emphasis on consumption reduction for mobile-terminals autonomy improvement. Key elements of the IR transceiver implementation are described. Experimental results for an LR diffuse channel are presented, showing the suitability of such a transmission technique for indoor hand-held terminals. Performances of the system are described in term of Bit Error Rate measurements.