Filtered modulation schemes for short distance infrared wireless communications

This paper describes two modem prototypes based on spectrally efficient fil tered modulations for infrared wireless links. They are fully compatible wi th commercial IrDA and IEEE 802.11 standards. These links allow more channe ls, giving a more accurate use of the infrared spectrum. We compare the per formances of the two main alternatives: phase (using FQPSK-2 systems) and f requency modulations (GMSK schemes). We have designed and tested 2Mb/s IR m odems with each modulation scheme. Extensive experimental results and BER m easurements of these prototypes are also detailed irt this paper.