Energy Efficient Integrated Circuits and Systems for Communication and Sensing: RF to Optical

The trend of continually increasing demand for high-performance computation requires increasing interchip communication throughput. On the contrary, high-throughput interchip links usually entail incorporating very high speed SerDes to mux/de-mux the data onto a relatively few electrical I/O lines. This not only incurs latency overhead but also a significant energy consumption overhead. An optical interface has great potential to ameliorate the interchip communication bottleneck. To this end, a major part of this thesis aims analysis and development of energy efficient integrated systems for parallel optical interchip communication. The experimental results of several multi Gbps optical transceiver prototypes fabricated in nanometer CMOS technologies prove the proposed optical links a promising technology for interchip communication. In addition, this dissertation theoretically compares power consumption of a parallel link with the serial counterpart for the same data throughput and shows a significant energy efficiency improvement for the parallel link. Moreover, a CMOS sensor is proposed that can measure the small capacitance of on-chip photodetectors which is a crucial parameter in optical receiver design.

In the remaining parts of the dissertation, the development of several energy efficient high performance integrated circuits for pulsed Lidar, pulsed Radar, and wireless communication systems are presented. More specifically, the design and test of an optimized pulsed lidar receiver fabricated in a CMOS technology is presented that remarkably reduces energy consumption. Also, a new transimpedance amplifier topology is introduced that enhances the energy efficiency of the conventional structures. In addition, a novel energy efficient pulse generator is introduced that systematically can produce a pulse with high amplitude and short width in any CMOS technology and deliver it to low impedance loads. Moreover, a wireless transmitter for short range communication in the mmWave frequency band fabricated in a BiCMOS technology is demonstrated that enables energy efficient high data rate communication.

Professor Ehsan Afshari