Ka-BAND PULSED PROPAGATION THROUGH RAIN-FILLED ATMOSPHERE

An atmosphere of rain offers a dispersi e medium for the propagation of radio signals abo e 10 GHz. The effect of dispersion, in terms of differential attenuation and phase dispersion, is insignificant for narrowband signals. Signals modulated with ery short pulses can ha e a wide bandwidth o er which dispersion will be appreciable, causing significant signal distortion. The propagation of pulsed signals under arying propagation conditions has been studied with the Fourier transform technique. The transfer function of the rain atmosphere is obtained using propagation models that include clear-air effects and scattering effects due to raindrops. The carrier signal at 30 GHz is considered to be modulated by a raised-cosine pulse with a base bandwidth of 1 3 GHz. A technique for the mitigation of pulse distortion using an FIR filter is presented to restore the distorted pulse to its original shape and position to a significant extent. 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 30: 105 109, 2001.