This research focuses on the co-design of electronic and photonic integrated circuits (ICs) for next-generation optical transceivers in high-speed datacom and high-frequency sensing applications. These applications include optical interconnects for computing systems, lidar for autonomous vehicles, and radio-over-fiber links for satellite payloads. Novel IC technologies will be explored, modeled, and experimentally validated. Co-design techniques will be investigated to optimize transceiver circuit performance, considering typical compromises between bandwidth, noise, linearity, signal integrity and power consumption. Control circuits may be co-integrated to adjust the operation of the circuitry based on e.g. temperature, wavelength or modulation scheme. Multiple design and fabrication cycles are planned to mitigate risks and uncertainties associated with new technologies and high-frequency operation.