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Integrated chips have enabled realization and mass production of complex systems in a small form factor. Through process miniaturization many novel applications in silicon photonics and electronic systems have been enabled. In this thesis I have provided several examples of innovations that are only enabled by integration. I have also demonstrated how electronics and photonics circuits can complement each other to achieve a system with superior performance.

Large aperture flexible and deployable phased arrays will enable active RF fabric and deployable array structures for terrestrial and space applications. The flexible phased array design paradigm is enabled by small, multi-function radio frequency integrated circuits and low mass radiators, which avoid conventional dielectric materials. This paper presents a 256 element, 30 cm x 30 cm flexible phased array, operating at 10 GHz and focusing 0.8 W at 2 m distance. A novel beam-focusing algorithm is used to demonstrate 2-D beam-steering and deformation correction capabilities of the flexible phased array.

Flexible and conformal phased arrays enable a broad range of novel applications. One of the major challenges for such systems is that they experience a change in their behavior when bent or deformed. A self-calibrating flexible phased array can overcome this by estimating the relative position change of its elements as they undergo local deformations. In this work, we demonstrate a dynamically flexible and conformal 8-element phased array based on a custom CMOS transceiver unit. Beam-steering is demonstrated with the flexible array flat and with the array conformed to convex and concave bend radii of ±120 mm. In addition, we propose and test a shape calibration method that uses only the coupling between elements, using the flexible phase array.

An integrated broadband Vivaldi antenna driven by an on-chip traveling-wave photodetector is reported. The silicon photonic chip radiates between 21 and 67 GHz with−65 dBm coupled power at 44 GHz.

Low-cost mm-wave silicon integrated signal generation and processing enable many applications, such as silicon-based automotive radars for self-driving cars and wireless communications. Some challenges encountered in commercialization of such systems are the high packaging and testing costs and high sensitivity to antenna parameters, which can diminish the advantage of integrated silicon solutions. On-chip antennas have been proposed as a solution to reduce the packaging costs [1,2]. Link budget analysis of systems (e.g., radar) necessitates high-power (high EIRP) transmitters while system resolution analysis suggests higher frequency of operation for better spatial resolution. The scaling of CMOS transistors facilitates the latter requirement, but, unfortunately, the lower breakdown voltage of the transistors reduces their maximum power handling capabilities at a given radiator impedance. Several approaches have already been implemented to address this issue, each with its own shortcoming. Power-combining multiple PA outputs with passive on-chip power combiners [3] adds extra loss and reduces the overall efficiency, spatial power combining using phased arrays [4] consumes a large die area. Power combining at the antenna [5,6] has been proposed as an approach to address these challenges. In this paper, we propose a spatial PA/radiator power combining approach with optimal PA-load design using strongly coupled antennas in close proximity. This approach utilizes techniques of power combining in free space resulting in favorable drive-point impedance design and using on-chip PAs and radiators to achieve high radiated output power.

We have fabricated a functional prototype of an ultralight power converter tile; a modular building block for a space-based solar power system. The tile is ∼10×15 cm in area, and weighs ∼1.5 kg/m^2. It comprises a photovoltaic (PV) solar energy collector, a radio-frequency (RF) power converter, and an array of transmission antennas. The PV collector subassembly utilizes ∼15x, 1D parabolic trough reflective concentrators with triple-junction (3J) solar cells. It has areal mass of ∼0.8 kg/m^2, 74% optical efficiency, and a peak specific power of ∼230W/kg. We demonstrated wireless power transmission over a distance of ∼50 cm in our lab. Analysis of the sources of mass and inefficiency suggest a path towards achieving dramatically higher performance with future designs.

We demonstrate the development of a prototype lightweight (1.5 kg/m^3) tile structure capable of photovoltaic solar power capture, conversion to radio frequency power, and transmission through antennas. This modular tile can be repeated over an arbitrary area to forma large aperture which could be placed in orbit to collect sunlight and transmit electricity to any location. Prototype design is described and validated through finite element analysis, and high-precision ultra-light component manufacture and robust assembly are described.

This paper presents an 8x8 optical phased array (OPA) receiver that operates as a lens-less camera using a heterodyne architecture on a thin silicon-photonics integrated SOI substrate. It has a receiving beam width of 0.75° and beam steering range of 8°.

A 10GHz fully-integrated stacked PA quad with dynamic digital feedback and control loops provides total output power of 200mW at 37% PAE. It utilizes data provided by multiple on-chip sensors to maintain safe operating conditions and regulate the individual power PA power supply voltages and independent power control for each PA. This digitally controlled stacked PA quad with on-chip matching allows higher operation voltages while maintaining current consumption constant, leading to higher overall system efficiency, as ohmic drop losses under large supply-to-breakdown voltage ratios are reduced.

This paper presents a thin silicon-photonics integrated one-dimensional lens-free camera based on an optical phased array receiver on an SOI process. The camera has beam steering range in excess of 60° with no blind spots, a beam width of 0.74°, and is used to form images.

We present a differential ring modulator that breaks the optical bandwidth/quality factor trade-off known to limit the speed of high-Q ring modulators. This structure maintains a constant energy in the ring to avoid pattern-dependent power droop.

A compact monolithically integrated Mach-Zehnder Interferometer Modulator operating above 1Gbps is demonstrated in an unmodified 180nm CMOS SOI process. This 50µm long structure allows for high density integration of photonics modulators and electrical driver circuitry on a single standard CMOS chip.

Integrated optics can provide low-loss broadband optical delay much more readily than electronics. On the other hand, electronic integrated circuits offer unparalleled levels of signal gain and signal processing on a single die. The hybrid electro-optical solutions benefiting from best of both domains can provide significant improvements overs solutions solely in one domain. In this paper, we present two examples of such hybrid electro-optical solutions.

An optically-wideband adjustable self-equalizing photo-detector (ASEPD), capable of reviving eye closure due to limited bandwidth of electro-optical components in an optical link, is presented. The ASEPD enables use of various slower electro-optical components in faster data links.

A self-equalizing photo-detector (SEPD) that mitigates the bandwidth limitations of electro-optical components of optical communication systems is demonstrated, enabling higher rate of data transmission, using slower components. Unlike other all-optical equalization schemes, SEPD is optically wide band, thus does not require wavelength tuning.

A compact silicon-photonics optically driven mm-wave radiator uses a multi-port driven travelling-wave antenna driven by 8 silicon photodiodes with -3dB bandwidth of 25GHz to produce -9.7dBm EIRP at 180GHz.

This paper presents electrical beam steering in an integrated 4x4 2D optical phased array (OPA) on a silicon on insulator (SOI) process enabling fast and repeatable beam steering for next generation projection, tracking, and imaging.