An Automatically Steering Optical Beam-Forming Network for Phased Array Antenna Based on Dense Wavelength Division Multiplexing

It is proposed an automatically steering optical beam-forming network (OBFN), which is consisted of an optical fiber loop structure. The loop structure is composed by an optical switch, an optical fiber splitter, and an optical true time delay lines based on dense wavelength division multiplexing (DWDM). The channel number of the DWDM is matched with the number of the phased array antennas (PAA). The true time delay difference between two adjacent channels is set as a basic step. And the optical wave modulated by radio frequency (RF) signal can run into the loop and suffer increased delay with increased circles. Thus the PAA is steered automatically without additional controlling and programming. The performance of this design is analyzed with its maximal circle numbers and the splitting ratio of the optical splitter in theory. The concept-proof experiments with 8 optical channels for DWDM are carried out and the simulation of the PAA radiation pattern is given.