Evaluation of a Spline-Based Parameterization Scheme for Phase-Only Antenna Pattern Synthesis

Phased Array Radars (PAR) are rapidly becoming the future for weather observations. The National Oceanic and Atmospheric Administration (NOAA) has identified PARs as a promising technology for polarimetric weather radar measurements. In particular, the ability of PARs to synthesize imaging beams with minimal sensitivity losses is becoming increasingly crucial for achieving the high-temporal resolution requirements. This paper introduces a novel phase-only beam pattern synthesis method using the Non-Uniform Rational B-Spline (NURBS) parameterization scheme. Based on a genetic algorithm optimization, it generates a phase distribution to excite the array and produce a desired beam shape. The proposed NURBS scheme is compared to previously used Bezier parameterization scheme. An S-band, 64-element uniform linear array (ULA) PAR was constructed to evaluate the performance of the NURBS scheme. Preliminary results show that the NURBS phase parameterization scheme can be used to synthesize phase weights for real-world PARs. Multiple metrics are used to evaluate the performance of the suggested parameterization scheme, such as half-power beamwidth and peak sidelobe levels. Results suggest that the NURBS scheme performs better than the Bezier scheme for synthesizing phase-only antenna patterns.