Professor of Electrical Engineering
Ph.D., Columbia University, 1979
M.Phil., Columbia University, 1978
M.S., in Electrical Engineering, Columbia University, 1976
A.B., Bowdoin College, summa cum laud, 1974
Room: B314 Engineering Quadrangle
Research Areas and Interests
- Photonic Systems, Non-linear Optics, Quantum Optics
- Security in Computing and Communications
- Signal Processing, Machine Learning, and Optimization
Research in my group, the Lightwave Communications Laboratory, is focused on investigating ultrafast optical techniques with application to communication networks and signal processing. My graduate students and I are working on several exciting and innovative research projects, which benefit from close collaborations with government and industrial research laboratories. A few examples of these projects fare given below:
Physical (Optical) Layer Network Security: Security in fiber optic networks is becoming of critical importance due to the nature and volume of the data that is transported. The optical layer of a network is itself vulnerable to attack by eavesdropping or jamming. My group is investigating several approaches using optical signal processing to counter these attacks, including optical steganography, all-optical encryption devices, anti-jamming techniques, and survivable network architectures.
Optical Code Division Multiple Access (CDMA):
Incoherent optical CDMA networks can offer several important system advantages that cannot be achieved with other multiplexing techniques such as TDM and WDM, including asynchronous access, soft blocking, privacy, scalability and variable quality of service. We are developing novel integrated technologies that will enable the realization of practical optical CDMA networks, which will be strong candidates for future broadband access networks.
Nonlinear Optical Signal Processing for Ultrafast Networks: Based on nonlinear phenomena in semiconductor devices and nonlinear fibers, numerous optical signal processing functions can be achieved which can enhance the performance of ultrafast optical networks. We are studying novel devices and their applications, including optical thresholding, auto-correlation peak extraction, demultiplexing, physical layer security enhancement, and interferometric noise suppression
Optical Cancellation of RF Interference: Wireless communictions systems often suffer from co-site interference, where the signal from a nearby transmission antenna interferes with simultaneously receiving a weak signal in a nearby frequency band. Multipath effects make this problem especially challenging. We are investigating optical and optoelectronic signal processing techniques to process RF signals from single antennas as well as phased arrays, enhancing their performance and enabling rapid reconfigurability.
The Photonic Neuron: Using nonlinear optical and photonic materials, we have recently built a hybrid analog/digital signal processing device which performs all the functions of a physiological neuron, but one billion times fast. Our spiking neuron is faster and more efficient than a digital computer, and does not suffer from the noise accumulation of analog electronics. Using the photonic neuron, we are implementing sophisticated, ultrafast signal processing circuits and systems which emulate visual, auditory, and motor functions found in biological organisms.
With a high degree of interaction between government and industrial research laboratories, the Lightwave Communications Laboratory offers students an opportunity to be involved in the creation of technology for the next generation of optical signal processing, computing and communications systems.
Please visit my lab website to find out more information about my group and our research, as well as to download a booklet containing some of our recent papers. To find out more about my group’s collaborations with industry, you can also visit the website of the Center for Network Science and Applications.
Honors and Awards
- SEAS Distinguished Teaching Award (2009)
- Walter Curtis Johnson Prize for Teaching Excellence (2009)
- Princeton University Graduate Mentoring Award (2006)
- Fellow of the OSA (1997)
- Fellow of the IEEE (1992)
- Rudolf Kingslake Medal and Prize, SPIE, for the most noteworthy original paper in Optical Engineering (1990)