The need for fast and reliable sensing at millimeter-wave frequencies has been increasing dramatically in recent years for a wide range of applications including non-destructive evaluation, medical imaging, and security screening such as concealed contraband detection. Imaging based approaches have been of particular interest since the wavelengths at millimeter-wave frequencies provide good resolution and are capable of propagating through clothing with negligible attenuation allowing the identification of concealed contraband. While various implementations for millimeter-wave imaging have been developed, the new technique of active incoherent millimeter-wave (AIM) imaging, developed in our research group, is of particular interest because it solves fundamental limitations inherent in other approaches. Furthermore, AIM enables imaging with significantly fewer elements than phased arrays and costs less than passive imagers. This is enabled by actively transmitting noise signals, allowing the system to capture scene information in the spatial Fourier domain. When the received signal at each of the array elements are spatio-temporally incoherent, the spatial coherence function of the captured signals represent samples of the measured visibility which can be further processed via an inverse Fourier transformation to recover the measured scene. With a good quality recovered image, additional processing can be applied for detection and/or classification on specific spatial features. However, images often contain more than the required information necessary for effective classification results which means that unnecessary resources are used for the collection and processing of redundant information.In this dissertation, I present on the design and analysis of array dynamics for radar and remote sensing applications. Specifically, I investigate approaches to measure specific spatial Fourier information which can be useful for direct classification therefore eliminating the need of full image recovery. I present an adapted formulation of the spatial coherence function by considering individual antenna trajectories within a dynamic antenna array. The measured visibility, hence, becomes a function of array trajectory over a slow time dimension. The use of array dynamics further reduces the hardware requirements in the AIM technique by introducing a new degree of freedom in the array design. By allowing the receiving elements of the antenna array to dynamically move across the measurement plane, the spatial Fourier domain can be efficiently sampled using as few as two receiving antennas. Discussion of the effects of trajectory approaches on the measured spatial Fourier information are presented. Furthermore, I expand on a specific array trajectory where as few as two antennas can generate a ring filter (i.e., spatial Fourier sampling function exhibiting a form of a ring) that can efficiently identify spatial Fourier artifacts pertaining to sharp edges in the scene. This approach enables an imageless approach to differentiate scenes containing objects with sharp-edge that are generally made artificially. I then present a real-time rotational dynamic antenna array operating at 75 GHz with two noise-transmitting sources as required by the AIM technique and two receivers to generate the ring filter. Compared to traditional millimeter-wave imaging, this non-imaging approach further reduces the required number of antennas. Experimental measurements using the AIM based rotational dynamic antenna array demonstrate the possibility of detecting concealed contraband via the direct measured spatial Fourier domain information.
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