Princeton University

School of Engineering & Applied Science

Microwave Photonic Filters for Interference Cancellation and Adaptive Beamforming

John Chang
Engineering Quadrangle B327
Friday, May 2, 2014 - 10:00am to 11:30am

Wireless communication has experienced an explosion of growth, especially in the past half-decade, due to the ubiquity in the use of personal connected wireless devices, such as tablets, WIFI-enabled or bluetooth enabled devices, and especially smartphones. Proliferation of smartphones with powerful processors and graphic chips have given an ever increasing amount of people the ability to access anything from anywhere. Unfortunately, this ease of access has greatly increased mobile wireless bandwidth and have already begun to stress carrier networks and spectra. Growth of these devices are expected to increase by 80%.

In this thesis, we will investigate optical signal processing methods for wireless interference cancellation methods. Optics provide the perfect backdrop for interference cancellation. Mobile wireless data is already aggregated and then transported through large fiber backhaul networks in practice. By sandwiching the signal processing stage between the receiver and the fiber backhaul, processing can easily be done locally in one location.

We present the world's first full, adaptive photonic beamformer. The solution is two-part. A novel highly-scalable photonic beamformer provides the backbone architecture.  Meanwhile, a new blind search algorithm, the guided accelerated random search (GARS) algorithm, has been developed specifically for the optical hardware.