Intensity Position Modulation for Free-Space Laser Communication System

In this study a novel analog modulation-demodulation technique for free-space laser communication system called Intensity Position Modulation (IPM) is carried out. According to TEM₀₀ mode of a laser beam and by linear fitting on the Gaussian function as an approximation, the variation of the linear part on the reverse biased pn photodiode produced various currents. Our simulated results show fine response bandwidth and fidelity of the analog communication system, is made upon the present method, is satisfactory. According to the present method, we are able to transmit the audio signals up to 1 Km.