Simultaneous Microwave Photonic Analog-to-Digital Conversion and Digital Filtering

We proposed a scheme which can simultaneously realize photonic analog-to-digital conversion (PADC) and digital photonic filtering for microwave signals. A multi-tap optical pulse shaper is adopted in a photonic sampling and electrical quantizing PADC to change its equivalent channel response, which can be designed and flexibly reconfigured as a finite impulse response digital filter. The principle and operation conditions of the proposed scheme are theoretically analyzed. A system employing an optical time division multiplexing (OTDM)-based multi-tap shaper is demonstrated. Filtering features agreeing well with the theoretical and simulation results are experimentally measured by configuring the path attenuations and delays in the OTDM based shaper.