How does PPM ( Pulse Position Modulation ) minimize the effect of atmospheric turbulence affecting the intensity of light in Photonics ?

Soumya Ranjan Sahoo @Soumya_Ranjan_Sahoo

07 July 2015 1 8K Report

Passband modulation and optical communication.

I'm not sure what is the situation you are considering, but very low duty cycle PPM enables one to maximise the peak power, hence maximising the peak received power, for the same mean transmitter power.

With sufficient bandwidth to resolve these narrow pulses, greater sensitivity can be achieved. I seem to remember a famous paper by Pierce & Posner proposing PPM as the optimum moduslation format for sensing signals back to Earth from a distant star: J. R. Pierce, E. C. Posner, and E. R. Rodemich, “The capacity of the photon-counting channel,” IEEE Trans. Inform. Theory 27, 61–77 (1981)

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