Optically Implemented Synchronized Low Frequency Sampling Methodology for Filtering and Recovery of Noise Embedded Narrow Band Signals

The growing use of information brings technology to the edge. The need to transmit data at ever increasing rates by wireless communication is fueling the desire to raise up the carrier's frequency. An optional frequency band that has been the subject of a very extensive academic research and industrial attention in recent years is the field of millimeter waves, including THz waves.

In this study we present an innovative and inexpensive receiver designed for high frequency (THz), which uses standard components and is implemented based on the principles of spatial optics and its duality with temporal imaging. The receiver is innovative in that the signal sampling is done by using 2 synchronized low-frequency samplers with relation to the carrier's frequency and without the need to down-convert  the signal to the IF frequency. The implementation is done by 2 main optical modules:

•       An Inversion module - is based on a 4-F temporal imaging system. The temporal equivalent of the spatial lens is applied by an electro-optic modulator.
•       A Temporal joint transform correlator – again based on a 4-F system with the effect of nonlinear optical crystal based on the difference frequency generation (DFG) process.

* M.Sc. research supervised by Prof. Meir Danino & Prof. Zeev Zalevsky