Implementation of a photonic-assisted adaptive spatial filter using HJ-LCMV optimization

We propose and experimentally demonstrate a photonic-assisted adaptive spatial filter (PASF) utilizing a Hooke-Jeeves-based LCMV (HJ-LCMV) optimization. By integrating a gradient-free direct search with the LCMV framework, the system adaptively adjusts optical weights based on real-time feedback to compensate for hardware non-idealities, thereby achieving interference suppression while preserving foundational beamforming characteristics. Outdoor field tests using a 28-element linear array at 10 GHz and 16 GHz achieve null-steering depths of 53.3 dB and 41.2 dB, respectively. The system also demonstrates the capability to form a wide null localized around the optimized frequency. This is the first, to our knowledge, TTD-based beamformer with integrated adaptive spatial anti-interference capabilities.