ACP-OPLL photonic integrated circuit for high dynamic range RF/photonic links

Fiber-optic links are attractive for transmitting microwave/millimeter wave signals for applications such as radar, imaging and astronomy. However, current fiber-optic links that employs intensity modulation and direct detection suffer from limited spurious free dynamic range (SFDR). For solution, a new coherent fiber-optic link using linear phase modulation/demodulation has been proposed. The new link should be able to achieve an SFDR two orders of magnitude higher. The key for this link is an Optical Phase Locked Loop (OPLL) linear phase demodulator. In this paper we describe the design and preliminary measurements for the first generation ACP-OPLL photonic integrated circuits.