Performance Comparison of Adaptive Algorithms in Identifying Clear Air and Rain Echoes in the 205 MHz-ST Radar Framework

Stratosphere-Troposphere Radar at Cochin is designed to measure height variation of three dimensional wind components using backscattered echo power from Bragg scattering. During rainy periods, the present signal processing techniques adopted is incapable of distinguishing the clear air echoes and rain echoes. This paper compares the performance of two adaptive algorithms and proposes the better one that alleviates the problem of distinguishing echoes in heavy rain conditions. This work is being attempted for the first time in ST Radar framework. Least Mean Square (LMS) and Normalized least mean square algorithms (NLMS) are applied on the spectral data and results are compared with raw data. It is found that NLMS algorithm performs better in distinguishing clear air turbulent echoes and rain echoes especially during heavy rain conditions.