FIG 2 (IMAGE) Compuscript Ltd Caption (a) Realization of 4-channel OTTDL based photonic beamformer (Input from port I2, and output from four PDs). Here light goes along the blue paths, and there is no light in the grey paths; (b) Experimental setup. Measured phase response (c) and group delay response (d) of the microwave signals for all 32 delay states of the first channel of delay line. The delay variations (e) and the measured S21 (f) for all four channels at 18 GHz. PC: polarization controller, Mod: modulator, VNA: vector network analyzer. Credit OEA Usage Restrictions Credit must be given to the creator. License CC BY Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.