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The ability to sense propagating electromagnetic plane waves based on their directions of arrival (DOAs) is fundamental to a range of radio frequency (RF) sensing, communications, and imaging applications. This paper introduces an algorithm for the wideband true time delay digital delay Vandermonde matrix (DVM), utilizing Thiran fractional delays that are useful for realizing RF sensors having multiple look DOA support. The digital DVM algorithm leverages sparse matrix factorization to yield multiple simultaneous RF beams for low-complexity sensing applications. Consequently, the proposed algorithm offers a reduction in circuit complexity for multi-beam digital wideband beamforming systems employing Thiran fractional delays. Unlike finite impulse response filter-based approaches which are wideband but of a high filter order, the Thiran filters trade usable bandwidth in favor of low-complexity circuits. The phase and group delay responses of Thiran filters with delays of a fractional sampling period will be demonstrated. Thiran filters show favorable results for sample delay blocks with a temporal oversampling factor of three. Thiran fractional delays of orders three and four are mapped to Xilinx FPGA RF-SoC technologies for evaluation. The preliminary results of the APF-based Thiran fractional delays on FPGA can potentially be used to realize DVM factorizations using application-specific integrated circuit (ASIC) technology. [ABSTRACT FROM AUTHOR]

In dental medicine, the study of mandibular movement has an important role in oral rehabilitation as it allows diagnosis of pathologies in the temporomandibular joint and the definition of adequate treatment plans. In this paper, a new device specially developed for the acquisition and analysis of 3D mandibular movement is presented. A facial arc is adopted as its main support structure and electromagnetic sensors are employed to acquire the mandibular movement. A neural network is used to transform the electrical signals output by the sensors into 3D Cartesian coordinates. A custom-made computer application is developed to display and analyse the movement acquired. The device is shown to be easy to use, comfortable for patients and capable of being produced at an affordable price. [ABSTRACT FROM AUTHOR]