Photonic Analog-to-Digital Conversion Technology

摘要

This report documents the work undertaken by HRL Laboratories, LLC and its subcontractors, California Institute of Technology and Raytheon Electronics Systems, on the development of multi-GHz photonic analog-to-digital (A/D) conversion technologies (PACT). Using an electro-optic modulator, the analog-input to the A/D converter was impressed (i.e. photonically sampled) on a train of low-jitter picosecond pulses (wavelength - 1540 rim) generated by a mode-locked Er-fiber laser. After photodetection, the electrical outputs of the photodiodes were fed to a variety of electronic quantizers for digitization. Specifically, the HRL Program demonstrated InP-HBT bandpass Delta-Sigma A/D converter with 10 bits of resolution, using photonic sampling at 10 GHz. The Program also demonstrated photonic clock distribution to multiple flash A/D converters, and a 40 GHz photonic time-interleaved architecture based on wavelength division multiplexed technologies. For the 40 GHz time-interleaved architecture, the program achieved --4 SFDR-bits of resolution. PACT is compatible with antenna remoting systems that utilize fiber optic links for signal distribution.