Beamforming Array Failure Correction for mm-Wave Synthetic Aperture Radar Applications

Millimeter-wave (mm-wave) beamforming arrays are advanced antennas, operating within the frequency range of 30–300 GHz. They have several applications, including unmanned aerial vehicle (UAV) communication, 5G technology, multiple input multiple output (MIMO) applications, and synthetic aperture radar (SAR). The rise of mm-wave technology has gained importance in SARs functioning as “two-way” communications, with radar signals traveling from transmitter to target and back to the receiver. This causes the received power to follow an inverse distance R4 relation, unlike the traditional “one-way” (R2) communications which employs cosecant power pattern. Since, the cosecant power pattern offers difficulties in achieving high-resolution imaging and sensitivity in mm-wave SAR systems, therefore a unique cosecant 4th power pattern is introduced, enabling precise energy focus on predefined directions. CMOS-equipped transmit/receive modules (TRMs) in mm-wave SAR may lead to antenna element failures, resultantly affecting the sidelobe levels, beamwidth, and gain in cosecant 4th power pattern. This research uses a genetic algorithm (GA) to correct element failures in a 6 × 12 array, aiming to recover the desired pattern with 8.33–25% failure of edge antenna elements. GA optimizes complex weights to align with the cosecant 4th power pattern, ensuring efficient performance in mm-wave SAR applications.