High Speed Integrated Circuits for High Speed Coherent Optical Communications

High Speed Integrated Circuits for High Speed Coherent Optical Communications by Hyun-chul Park With the development of (sub) THz transistor technologies, high speed integrated circuits up to sub-THz frequencies are now feasible. These high speed and wide bandwidth ICs can improve the performance of optical components, coherent optical fiber communication, and imaging systems. In current optical systems, electrical ICs are used primarily as driving amplifiers for optical modulators, and in receiver chains including TIAs, AGCs, LPFs, ADCs and DSPs. However, there are numerous potential applications in optics using high speed ICs, and different approaches may be required for more efficient, compact and flexible optical systems. This dissertation will discuss three different approaches for optical components and communication systems using high speed ICs: a homodyne optical phase locked loop (OPLL), a heterodyne OPLL, and a new WDM receiver architecture. The homodyne OPLL receiver is designed for short-link optical communication systems using coherent modulation for high spectral efficiency. The phase-locked coherent receiver can recover the transmitted data without requiring complex back-end digital signal processing to recover the phase of the received optical carrier. The main components of the homodyne OPLL are a photonic IC (PIC), an