Signal correlator with programmable variable time delay based on optical coherent transients

We have demonstrated a technique for programming variable time delays of a pattern waveform in a spectral grating. By frequency shifting the chirped programming pulses, correlation and delays over 450 ns were achieved without changing the programming sequence timing. The demonstrated bandwidth of 40 MHz only utilized ~0.2 % of the inhomogeneously broadened absorber´s bandwidth. Thus, this technique has the potential to allow versatile, all-optical reception and processing of > 10 GHz signals in broadband array antenna beamforming