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Recently, new techniques for passive imaging based on distributed aperture imagers have been developed. One promising approach utilizes photonic sampling, routing, and processing of the millimeter-wave energy for image generation. Many signal processing aspects of this approach that have been explored to date, from engineering phase profiles across the array to achieve dynamically adjustable point spread functions, to noise reduction techniques in the optical image regeneration. Herein, we focus on a method to reduce image bias in a distributed aperture millimeter wave imager by switching the phase in individual channels by π-phase. Our simulations indicate this approach has better bias performance than random phase switching.

In this paper, we introduce a new millimeter wave imaging modality with extended depth-of-field that provides diffraction limited images based on a significant reduction in scan-time. The technique uses a cubic phase element in the pupil of the system and a nonlinear recovery algorithm to produce images that are insensitive to object distance. We present experimental results that validate system performance and demonstrate a greater than four-fold increase in depth-of-field with a reduction in scan-time by a factor of at least two.

The Micro Autonomous Systems and Technology program is conducting research to develop small air and ground robotic systems for acquisition and delivery of improved situational awareness to warfighters.

In this paper we demonstrate the miniaturization of a loop antenna through simulation and experiment using synthetic reactive elements, namely split ring resonators (SRRs), embedded in the substrate of the antenna. Two designs were considered with SRRs both in and out of the plane of the substrate. Simulation results show that antenna size can be reduced up to thirty eight percent for both designs. However, due to ease of fabrication, the in-plane configuration is the preferred design. Simulation and experimental results are presented.

Summary form only given. We have demonstrated an integrated optoelectronic MCM that uses a glass substrate as a mechanical carrier for the VCSEL, VCSEL driver, and diffractive element. Over a distance a little longer than 1 mm, our system fanned-out a single VCSEL into 60 individual fan-outs.