Rate-Adaptive Indoor Infrared Wireless Communications Systems Using OOK Formats with Memory and Variable Silence Periods

摘要

In this paper, a new and simple rate-adaptive transmission scheme for indoor unguided optical links is proposed. This scheme is based on the use of variable silence periods, allowing the increase of the peak-average optical power ratio, which is a favorable characteristic in intensity modulation and direct detection channels. These variable silence times are used for modifying the statistics of the amplitude sequence regarding the statistics of the message sequence when OOK formats with Gaussian pulses are adopted, obtaining a good trade-off between performance and required complexity. Here, it is applied to links operating at high bit rate initially, providing a signaling rate with a wide dynamic range and requiring a very low-complexity implementation. The authors compare this scheme in terms of performance and complexity with the scheme proposed by the IrDA, which is based on repetition coding and pulse-position modulation.