Simplified active array L-band radar for atmospheric wind profiling: initial results

Abstract

A simple approach is presented to implement an active aperture radar with a constrained beam-forming network that is adequate enough to generate multiple beams for atmospheric wind profiling. In this approach, elements of the antenna array are fed directly by dedicated transceiver modules, which are realized with commercially available communication components, making them low cost. A passive 2D beam-forming network distributes the exciter output signal and feeds the transceivers with appropriate phase distribution to generate different beams. This configuration, which is a simplified active array, eliminates the feed loss and achieves the best signal-to-noise ratio (SNR), thereby increases range coverage. Consequently, this scheme allows for a smaller antenna size when compared to a conventional passive array system, for the given range performance, and makes the wind profiler compact and transportable. A 1280-MHz, 64-element simplified active array radar has been developed, successfully validated, and is being operated at Gadanki, a tropical station in south India. Measured winds are in good agreement with those obtained with a collocated GPS sonde technique. This paper presents the configuration and sample results of the system.