Pulse-position modulation

Pulse-position modulation (PPM) is a form of signal modulation in which M message bits are encoded by transmitting a single pulse in one of $2^{M}$ possible required time shifts.^[1]^[2] This is repeated every T seconds, such that the transmitted bit rate is $M/T$ bits per second. It is primarily useful for optical communications systems, which tend to have little or no multipath interference.

^ K. T. Wong (March 2007). "Narrowband PPM Semi-Blind Spatial-Rake Receiver & Co-Channel Interference Suppression" (PDF). European Transactions on Telecommunications. 18 (2). The Hong Kong Polytechnic University: 193–197. doi:10.1002/ett.1147. Archived from the original (PDF) on 2015-09-23. Retrieved 2013-09-26.
^ Yuichiro Fujiwara (2013). "Self-synchronizing pulse position modulation with error tolerance". IEEE Transactions on Information Theory. 59: 5352–5362. arXiv:1301.3369. doi:10.1109/TIT.2013.2262094.

[1] K. T. Wong (March 2007). "Narrowband PPM Semi-Blind Spatial-Rake Receiver & Co-Channel Interference Suppression" (PDF). European Transactions on Telecommunications. 18 (2). The Hong Kong Polytechnic University: 193–197. doi:10.1002/ett.1147. Archived from the original (PDF) on 2015-09-23. Retrieved 2013-09-26.

[2] Yuichiro Fujiwara (2013). "Self-synchronizing pulse position modulation with error tolerance". IEEE Transactions on Information Theory. 59: 5352–5362. arXiv:1301.3369. doi:10.1109/TIT.2013.2262094.

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