A novel high-order FIR photonic signal processor

A new topology for realizing a high-order FIR RF photonic filter is presented. It is based on a novel structure that uses wavelength conversion and a routing technique to enable a multiple-pass transmission of the signal to be obtained through a single photonic sub-filter. The sub-filter can be of low order, however the routing of the output of the sub-filter back to itself several times together with some additional coefficients, realizes a high-order filter. Experimental results are presented which demonstrate a high-order FIR photonic filter realization comprising 39 taps.