Design and Implementation of Processes and Components for Optical Beam Forming Networks

Abstract

Optical beamforming networks (OBFNs) are a strong contender for phased array operation, especially using microwave photonics (MWP), with advantages in size, weight, power efficiency and cost. Applications for such systems range from satellite to cellphone communication. The use of OBFNs require multiple components to up-convert, down-convert and process radio frequency (RF) signals in the optical domain. In this thesis, these components and a photonic packaging solution were designed and tested. For the OBFN itself, the modulation for up-conversion was performed with a micro-ring modulator, which was able to perform 1.11V forward bias modulation at 500MHz with a modulation depth of 21 dB. A true time delay optical ring resonator (ORR) was designed and characterized, yielding 784 ps delay at 3.33V heater bias, tunable to any value below this. An accessible, low-cost photonic packaging approach was developed, which achieved an optical coupling loss of 2.8 dB per facet. In conjunction with the photonic packaging was an electromagnetic interference (EMI) enclosure, which was able to block unwanted external RF signals.