Topic
Phased array
About: Phased array is a research topic. Over the lifetime, 19428 publications have been published within this topic receiving 229231 citations. The topic is also known as: Phased Array Radar, PAR.
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the concept of true-time-delay steering for phased array antennas and its advantage over phase shifters in broadband applications are described with particular emphasis on the potential advantages offered by fiber-optic delay lines.
Abstract: The concept of true-time-delay steering for phased array antennas and its advantage over phase shifters in broadband applications are described with particular emphasis on the potential advantages offered by fiber-optic delay lines. The system architecture of the phased array antenna and the design and performance of the fiber-optic time-shifter networks in the antenna are described. The radiation patterns of the phased array antenna at L and X bands are presented. Using semiconductor laser switching to implement the delay times, the absence of beam squint in the antenna pattern and its frequency was switched from L to X band is demonstrated. >
421 citations
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TL;DR: Substantial improvements offered by the proposed phased-MIMO radar technique are demonstrated analytically and by simulations through analyzing the corresponding beam patterns and the achievable output signal-to-noise-plus-interference ratios.
Abstract: We propose a new technique for multiple-input multiple-output (MIMO) radar with colocated antennas which we call phased-MIMO radar. The new technique enjoys the advantages of the MIMO radar without sacrificing the main advantage of the phased-array radar which is the coherent processing gain at the transmitting side. The essence of the proposed technique is to partition the transmit array into a number of subarrays that are allowed to overlap. Then, each subarray is used to coherently transmit a waveform which is orthogonal to the waveforms transmitted by other subarrays. Coherent processing gain can be achieved by designing a weight vector for each subarray to form a beam towards a certain direction in space. Moreover, the subarrays are combined jointly to form a MIMO radar resulting in higher angular resolution capabilities. Substantial improvements offered by the proposed phased-MIMO radar technique as compared to the phased-array and MIMO radar techniques are demonstrated analytically and by simulations through analyzing the corresponding beam patterns and the achievable output signal-to-noise-plus-interference ratios. Both analytical and simulation results validate the effectiveness of the proposed phased-MIMO radar.
413 citations
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TL;DR: A very simple coded excitation for phased arrays based on the principles of 'pseudochirp' excitation and equalization filtering is described, capable of SNR improvements of about 15 dB with range sidelobe levels acceptable for many medical imaging applications.
Abstract: Based on an analysis of the inherent signal-to-noise ratio (SNR) in medical ultrasound imaging, SNR improvements of 15-20 dB are theoretically possible for real-time phased-array imagers using coded excitation. A very simple coded excitation for phased arrays based on the principles of 'pseudochirp' excitation and equalization filtering is described. This system is capable of SNR improvements of about 15 dB with range sidelobe levels acceptable for many medical imaging applications. Such improvements permit increased operating frequencies, and hence enhanced spatial resolution, for real-time array imagers. Both simulations and measurements are used to demonstrate the efficacy of the method. >
404 citations
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TL;DR: In this article, a comprehensive study of infinite phased arrays of printed dipole antennas is presented, with emphasis on the scan blindness phenomenon, and a simple theory, based on coupling from Floquet modes to surface wave modes on the substrate, is shown to predict the occurrence of scan blindness.
Abstract: A comprehensive study of infinite phased arrays of printed dipole antennas is presented, with emphasis on the scan blindness phenomenon. A rigorus and efficient moment method procedure is used to calculate the array impedance versus scan angle. Data are presented for the input reflection coefficient for various element spacings and substrate parameters. A simple theory, based on coupling from Floquet modes to surface wave modes on the substrate, is shown to predict the occurrence of scan blindness. Measurements from a waveguide simulator of a blindness condition confirm the theory.
384 citations