Results 21 to 30 of about 2,109,467 (140)
, 2018 Quantitative ultrasound techniques for assessment of bone quality have been attracting significant research attention. The axial transmission technique, which involves analysis of ultrasonic guided waves propagating along cortical bone, has been proposed
Shigeaki Okumura +5 more
semanticscholar +1 more source
Movable-Antenna Array Enhanced Beamforming: Achieving Full Array Gain with Null Steering [PDF]
arXiv, 2023 Conventional beamforming with fixed-position antenna (FPA) arrays has a fundamental trade-off between maximizing the signal power (array gain) over a desired direction and simultaneously minimizing the interference power over undesired directions. To overcome this limitation, this letter investigates the movable antenna (MA) array enhanced beamforming ...
arxiv
Microphone array signal processing for robot audition
Joint Workshop on Hands-free Speech Communication and Microphone Arrays, 2017 Robot audition for humanoid robots interacting naturally with humans in an unconstrained real-world environment is a hitherto unsolved challenge. The recorded microphone signals are usually distorted by background and interfering noise sources (speakers)
Heinrich W. Löllmann +6 more
semanticscholar +1 more source
Sparse Sensing with Semi-Coprime Arrays [PDF]
, 2018 A semi-coprime array (SCA) interleaves two undersampled uniform linear arrays (ULAs) and a $Q$ element standard ULA. The undersampling factors of the first two arrays are $QM$ and $QN$ respectively where $M$ and $N$ are coprime. The resulting non-uniform linear array is highly sparse.
arxiv +1 more source
Deep Learning-Aided Subspace-Based DOA Recovery for Sparse Arrays [PDF]
arXiv, 2023 Sparse arrays enable resolving more direction of arrivals (DoAs) than antenna elements using non-uniform arrays. This is typically achieved by reconstructing the covariance of a virtual large uniform linear array (ULA), which is then processed by subspace DoA estimators.
arxiv
Sparse Active Rectangular Array with Few Closely Spaced Elements [PDF]
, 2018 Sparse sensor arrays offer a cost effective alternative to uniform arrays. By utilizing the co-array, a sparse array can match the performance of a filled array, despite having significantly fewer sensors. However, even sparse arrays can have many closely spaced elements, which may deteriorate the array performance in the presence of mutual coupling ...
arxiv +1 more source
Pattern Synthesizing of the Concentric Ring Arrays Using Recursive Least Square Method [PDF]
arXiv, 2023 This letter presents a recursive technique to synthesize the array factor (AF) of a concentric ring array. In this method, first, the problem is modeled using the traditional least square method (LSM). In the second step, a recursive technique is applied to the defined problem.
arxiv
On Sparse Methods for Array Signal Processing in the Presence of Interference
IEEE Antennas and Wireless Propagation Letters, 2015 We analyze the performance of several algorithms designed to solve the inverse sparse problem when they are applied to array signal processing. Specifically we study the error on the estimation of the complex envelope and the direction of arrival of ...
Sebastian Pazos +2 more
semanticscholar +1 more source
Hybrid Sparse Array Beamforming Design for General Rank Signal Models [PDF]
, 2019 The paper considers sparse array design for receive beamforming achieving maximum signal-to-interference plus noise ratio (MaxSINR) for both single point source and multiple point sources, operating in an interference active environment. Unlike existing sparse design methods which either deal with structured environment-independent or non-structured ...
arxiv +1 more source
Near-field focusing using phased arrays with dynamic polarization control [PDF]
arXiv, 2022 Phased arrays in near-field communication allow the transmitter to focus wireless signals in a small region around the receiver. Proper focusing is achieved by carefully tuning the phase shifts and the polarization of the signals transmitted from the phased array. In this paper, we study the impact of polarization on near-field focusing and investigate
arxiv