Photonic Approach to Phased Array Application

Abstract

Many applications, including phased array antennas, require a significant and tunable time delay, which pure electrical methods cannot establish. A variable microwave true-time delay line utilizing a photonic approach is presented in this paper. The variation of the delay is achieved by the application of dispersive fiber and tunable laser. With this method, the tunable delay line can control multiple radiating elements. In this paper, both DWDM and CWDM solutions are theoretically investigated and compared. The experimental work applying DWDM tunable laser validates the theoretical analysis. Finally, the Phased array concept is presented, and the system simulation shows the operation. The suggested phased array feeding method requires only one laser source, an external intensity modulator, passive combiners, and dividers instead of multiple optical transmitters with multiplexers and demultiplexers.