Wideband Analog Photonic Lag Correlator for RF Signal Processing

We report a novel microwave-photonic architecture, that enables to compute the cross-correlation function of two input RF signals, for more than 200 values of the relative delay simultaneously. Our system, based on two frequency shifting loops, is particularly simple and enables the correlation of multi-GHz signals. We apply this architecture to the localization of RF transmitters by time difference of arrival.