Real-Time Optronic Beamformer on Receive in Phased Array Radar

Abstract

The development of phased array radar beamforming technologies has led to an ever-increasing demand for large antenna arrays and multiple beams. However, real-time processing becomes a difficulty for large array or multibeam beamforming due to huge data amount. To overcome the electronic mass data processing speed limitations, optronic technique is developed for beamforming in this letter. We present a novel real-time multibeam optronic beamforming (OPBF) system specially designed for large phased array. In our system design, beamforming is formulated as a finite-impulse response filtering process, of which radar raw data and weighting coefficients are encoded onto the laser beam by joint amplitude and phase control (JAPC) modules and two-dimension adding is performed by a lens. Ultrafast optical calculation and the proposed high-speed JAPC module make the system powerful for real-time processing. The proposed system has good expansibility in data capacity, which makes it applicable to massive data processing. What’s more, a practical low-power optronic beamformer is demonstrated. Measured results show that the presented OPBF system is able to accurately synthesize flexible and controllable multibeams and performs well in channel equalization.