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A new method of detecting the angular velocity of moving objects using correlation interferometry is presented. As an object passes through the interferometer beam pattern, the frequency of the signal response is directly proportional to the angular velocity of the object. Only a simple frequency analysis is required to measure the velocity, whereas typical techniques require angle estimation and multiple looks to calculate the rate of angular change over time. The general response of the interferometer is derived, as well as the fringe frequency. The method is verified by detecting the angular velocity of a walking human with a millimeter-wave correlation interferometer, and experimental results of a walking human are presented.

A decentralized approach for joint frequency and phase synchronization in distributed antenna arrays is presented. The nodes in the array locally broadcast signals to share their frequencies and phases with their neighboring nodes, and use consensus averaging to align these parameters across the array. The architecture is fully distributed, requiring no centralization. Each node has a local oscillator and we consider a signal model where intrinsic frequency and phase errors of the local oscillators on each node caused by the frequency drift and phase jitter as well as the frequency and phase estimation errors at the nodes are included and modeled using practical statistics. A decentralized frequency and phase consensus (DFPC) algorithm is proposed which uses an average consensus method in which each node in the array iteratively updates its frequency and phase by computing an average of the frequencies and phases of their neighboring nodes. Simulation results show that upon convergence the DFPC algorithm can align the frequencies and phases of all the nodes up to a residual phase error that is governed by the oscillators and the estimation errors. To reduce this residual phase error and thus improve the synchronization between the nodes, a Kalman filter based decentralized frequency and phase consensus (KF-DFPC) algorithm is presented. The total residual phase error at the convergence of the KF-DFPC and DFPC algorithms is derived theoretically. The synchronization performances of these algorithms are compared to each other in light of this theoretical residual phase error by varying the duration of the signals, connectivity of the nodes, the number of nodes in the array, and signal to noise ratio of the transmitted signals. Simulation results demonstrate that the proposed KF-DFPC algorithm Manuscript received 2022.

We present experimental results of 10-Gb/s W-band wireless transmission using a four element linear array. The 10-Gb/s transmission is shown when photonically steered to 0°and ±35°from antenna boresight. In this letter, photonic techniques are used for signal generation, distribution, and time delay. Photonic true-time delay is shown to allow for steering of broadband millimeter-wave signals with no noticeable beam squint across frequency. High power, high frequency photodiodes are used for optical-to-electrical conversion to directly radiate from the array without power amplifiers.Index Terms-Microwave photonics, millimeter wave communication, phased arrays, true-time delay.