Intellectual Merit: Fields as diverse as physics, environmental science, and sociology have all been dramatically transformed by the ability to utilize large amounts of data, whether it comes from computers, sensors, storage or imaging. However, the relatively "slow" speed of electronic signal processors compared to the rate at which new data is acquired is creating a bottleneck in the timely processing of data. Signal processing may involve: (a) image refining requiring signal processing on all parts of the data, and optical processing can operate with high data rate, or (b) pattern recognition requiring "scanning" (i.e., correlating) of the large data to locate a desired feature, and optical processing can potentially take Terabytes of data, rapidly identify key requested features, and then allow electronics to process Gigabytes with more detail. This proposal is to research tunable, reconfigurable complex-coefficient tapped-delay-line optical processors to enhance the processing speed for pattern recognition and data processing. The approach utilizes multiple lasers as optical pumps, a dispersive element with a wavelength-dependent propagation speed, nonlinear wave mixers, and a phase/amplitude programmable filter. All parameters of the proposed scheme (i.e., tap delays and coefficients) can be tuned by varying the power and wavelength of the pump lasers. This allows for bit-rate tunable, data-modulation-format transparent phase/amplitude processing of an optical data signal. This scheme can be used as a building block to realize more advanced functionalities, such as 2-dimentional discrete Fourier transforms.
Broader Impact: This technology has the potential to directly advance many areas that use sophisticated data and image processing (e.g., environmental science, energy and sociology) by providing the capability to sift through very large data sets at faster speeds due to the high-speed ability to encode and manipulate multiple aspects of an optical wave. It can potentially enable new schemes for signal processing and reduce the time of searches within images and video data sets. This proposal hopes to utilize the large bandwidth of optics to perform digital data processing in a fully tunable and reconfigurable fashion, and to hopefully change the way Terabytes of data is processed by significantly improving the processing speed. Given the inter-connection between optics and electronics in this approach, multidisciplinary aspects can be pursued and potentially inspire novel hybrid optical/electronic architectures. Moreover: (a) high-school students will be exposed to the research, and (b) undergraduate and graduate students from diverse backgrounds will receive research training in a multidisciplinary experimental lab environment.
