Design and implementation issues of a wireless infrared Ethernet link

The design and implementation of a wireless infrared Ethernet link is considered. It is shown that, using commercially available devices, it is technical and economically feasible to implement wireless infrared extensions of Ethernet networks, maintaining the degree of complexity in transceiver electronics at very low level. In particular, it is shown that Manchester coding can still be used in the infrared path without impairing system range and performance. A laboratory prototype was developed and implemented using Manchester coding, achieving a bit error rate of 10^-10 over a range typical of normal office environments. The utilization of low cost lenses, both for the LED´s radiation pattern correction and as optical power collecting elements, was investigated and shown to provide significant performance improvements