Introductionalso sometimes known as pulse-phase modulationthe amplitude and width of the pulse is kept constant in the systemthe position of each pulse, in relation to the position of a recurrent reference pulse, is varied by each instantaneous sampled value of the modulating waveCont..often used in optical communication, such as fber optics, in which there is little multipath way interferenceused exclusively for transferring digital signals and cannot be used with analog systemsused for transferring simple data and is not efective at transferring fleshas the advantage over pulse amplitude modulation (P!" in that it has a higher noise immunity re#uiring constant transmitter power since the pulses are of constant amplitude and durationsignal and noise separation is very easydepending on transmitter-receiver synchroni$ationhighly sensitive to multipath way interferencePulse position modulation can be used for a number of purposes, especially in %& (%adio &re#uency" communications' -&or example(pulse position modulation is used in remote-controlled aircraft, cars, boats, and other vehicles and is responsible for conveying the controls of a transmitter to a receiver' )he position of each pulse may describe the physical direction of an analogue controller while the number of pulses may describe the number of possible commands that the device may receive'