Multitap microwave photonic filter based on a DFB laser array using photonic wire bonding

We propose and experimentally demonstrate a multitap microwave photonic filter (MPF) based on a distributed feedback (DFB) laser array using photonic wire bonding (PWB). Through the application of the PWB technique, an eight-wavelength DFB laser array with wavelength spacing of 400 GHz was hybrid-integrated with an arrayed waveguide grating multiplexer. Remarkably, the insertion losses of all eight channels are maintained below 5 dB. In the experiments, the larger wavelength spacing allowed us to achieve a sinc MPF with a lower 3 dB bandwidth of 0.22 GHz using only eight taps. Further, Gaussian apodization enabled the out-of-band rejection of the filter to reach 24 dB. These results indicate that the proposed scheme could provide a promising guideline for the MPFs that demand high reconfigurability and greatly reduced size and complexity.