HNLF-based photonic pattern recognition using remote transmitter

In this letter, a novel correlation technique based on matched filtering using four wave mixing with possible remote transmission is proposed. A pump wavelength, which is modulated by an input bit pattern is mixed with wavelength channels in a highly nonlinear fiber to generate idler wavelengths, which also carry the bit stream. Specific idler wavelengths are selected using software control of an optical processor to generate the reference template. These idlers are then differentially delayed and summed at a photodetector to produce the required correlation function. This scheme has been experimentally demonstrated and the measured results verify the proposed concept.