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High gain beamforming method in low-frequency band using virtual array migration

APPLIED ACOUSTICS 2025年 232卷

作者： Hu, Yuan Yin, Jingwei Li, Tianxing Cao, Jianguo Zhang, Liang Harbin Engn Univ 145 Nantong St Natl Key Lab Underwater Acoust Sci & Technol 145 Nantong St Harbin Peoples R China Harbin Engn Univ Minist Educ Key Lab Polar Acoust & Applicat 145 Nantong St Harbin Peoples R China Harbin Engn Univ Coll Underwater Acoust Engn 145 Nantong St Harbin Peoples R China Harbin Engn Univ Key Lab Marine Informat Acquisit & Secur Minist Ind & Informat Technol 145 Nantong St Harbin Peoples R China Chinese Acad Sci Key Lab Underwater Acoust Environm 21 North 4th Ring Rd Beijing Peoples R China

When measuring the low-frequency radiated noise of underwater low-noise targets, a conflict arises between the large-scale array's ability to achieve low-frequency gain and the reduction of propagation loss at a fixed measurement distance. This paper presents a method for virtual array element migration, based on the measured phase modulation of array elements. By increasing the phase differences between adjacent elements and further enhancing the phase differences between steering vectors in different directions, the proposed method improves the suppression of undesired directional interference signals, thereby enabling high-gain measurements under limited aperture conditions. To mitigate the reduction in robustness associated with virtual array construction, a virtual array factor is introduced for analysis. The results demonstrate that when the virtual array factor is set to 1, the proposed method performs comparably to conventional beamforming. When the virtual array factor exceeds 1, it can effectively enhance the suppression of interference signals in the low-frequency range. The optimal value of this factor should be selected based on the signal-to-noise ratio of the data to ensure the robustness of the algorithm. Both simulation and lake test data demonstrate that the proposed algorithm significantly outperforms conventional methods in terms of its ability to reject interference in low-frequency radiated noise measurements.

关键词： Radiated Noise Measurement Beamforming virtual array virtual array Factor Low-Frequency Band High gain

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virtual array beamforming of GPS TEC observations of coseismic ionospheric disturbances near the Geomagnetic South Pole triggered by teleseismic megathrusts

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JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS 2015年第10期120卷 9087-9101页

作者： Gomez, Demian Smalley, Robert, Jr. Langston, Charles A. Wilson, Terry J. Bevis, Michael Dalziel, Ian W. D. Kendrick, Eric C. Konfal, Stephanie A. Willis, Michael J. Pinon, Diego A. Cimbaro, Sergio R. Caccamise, Dana Univ Memphis Ctr Earthquake Res & Informat Memphis TN 38152 USA Ohio State Univ Sch Earth Sci Columbus OH 43210 USA Univ Texas Austin Inst Geophys Austin TX USA Cornell Univ Earth & Atmospher Sci Ithaca NY USA Inst Geog Nacl Buenos Aires DF Argentina

We identified coseismic ionospheric disturbances (CID) in Antarctica generated by the 2010 Maule and the 2011 Tohoku-Oki earthquakes analyzing total electron content (TEC) data with a modified beamforming technique. Beamforming in Antarctica, however, is not straightforward due to the effects of array deformation and atmospheric neutral wave-ionospheric plasma coupling. We take these effects into account and present a method to invert for the seismically generated acoustic wave using TEC observations. The back azimuths, speeds, and waveforms obtained by the beamform are in excellent agreement with the hypothesis that the TEC signals are generated by the passage of Rayleigh waves from the Maule and Tohoku-Oki earthquakes. The Tohoku-Oki earthquake is similar to 12,500km from Antarctica, making this the farthest observation of CIDs to date using GPS.

关键词： ionosphere Antarctica total electron content coseismic ionospheric disturbances virtual array beamforming

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virtual array Response Vector for Angle Estimation of MIMO Radar With a Wide-Band Interleaved OFDM Signal

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IEEE COMMUNICATIONS LETTERS 2021年第5期25卷 1539-1543页

作者： Lee, Hyukjung Chun, Joohwan Korea Adv Inst Sci & Technol KAIST Sch Elect Engn Daejeon 34141 South Korea Samsung Elect Hwaseong 18448 South Korea

Direction of arrival (DOA) in MIMO radar is estimated from the phase differences between its channels. Hence, the phase difference vector, called a virtual array response vector, needs to be accurately known. We propose a new model of the virtual array response with a wide-band interleaved orthogonal frequency-division multiplexing (OFDM) signal. The angle is estimated by maximum likelihood estimation (MLE), and we show that the estimation error is lower than the one when using the systematic phase correction method which compensates for the range-dependent phase term. Also, the root mean square error (RMSE) of angle estimation with the proposed method is closer to the Cramer-Rao bound (CRB).

关键词： Angle estimation Cramé r-Rao bound (CRB) multiple-input multiple-output (MIMO) radar orthogonal frequency-division multiplexing (OFDM) virtual array

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A high-resolution DOA estimation via random forest virtual array extension

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AEU-INTERNATIONAL JOURNAL OF ELECTRONICS AND COMMUNICATIONS 2024年 185卷

作者： Zhou, Qian Wang, Zhigao Huang, Lijun Zhang, Qiang Zhou, Yuchang Yuan, Chao Hunan Univ Elect & Informat Engn Changsha 420084 Peoples R China Hunan Univ Greater Bay Area Inst Innovat Guangzhou 510000 Peoples R China

In sonar detection, underwater recognition, and similar fields, the challenge of using small-scale arrays is frequently encountered. With small-scale arrays, the degrees of freedom (DOFs) and accuracy of direction of arrival (DOA) estimation decrease significantly. Moreover, existing algorithms are less robust in complex environments and typically require substantial computing resources to ensure accurate estimation. To overcome these problems, this paper proposes a high-resolution DOA estimation via Random Forest virtual array extension (RFVAE). The algorithm first trains the random forest (RF) network using real array element data, and thus proposes a virtual covariance reconstruction technique. This technique allows for a substantial increase in the number of virtual array elements. Then, based on the virtual covariance reconstruction technique, a high resolution estimation network technique is proposed, which can increase the accuracy and DOFs of DOA estimation. Experimental results show that the proposed algorithm reduces error by 30% to 80% compared to recent technologies and can provide up to twice as many virtual elements. Additionally, the estimation speed can be increased by 3 to 1000 times, and it has significantly stronger robustness, functioning normally at signal-to-noise ratios 10 dB lower than the conditions under which other algorithms fail.

关键词： DOA estimation virtual array Random forest network virtual covariance matrix reconstruction

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Time delay estimation algorithm based on virtual array and MUSIC for single sensor system

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PEER-TO-PEER NETWORKING AND APPLICATIONS 2019年第6期12卷 1519-1527页

作者： Fan, Di Zhu, Chunwei Lv, Changzhi Shandong Univ Sci & Technol Qingdao 266590 Shandong Peoples R China

Aiming at improving time delay estimation (TDE) in the case of single sensor, a novel method of constructing virtual sensor array is presented, and furthermore the MUSIC delay estimation algorithm based on the virtual array is proposed. The approach and complete procedure of the algorithm are given. The relationship between the number of virtual array elements and the constructed signal is studied, and the method of determining the minimum number of elements under the condition of estimation time delay accurately is given. The simulation experiments of the presented algorithm have been carried out from three angles of view. The least virtual array elements and the minimum subspace dimensions needed in this algorithm is verified. We obtained the performance of time delay estimated by the algorithm under sparse path and dense path conditions respectively. This paper also illustrated the high precision and high-resolution characteristics of the proposed method.

关键词： virtual array Time delay estimation algorithm Multiple signal classification Single sensor

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Simplified Multipath Propagation Measurement Scheme for DOA and Delay Based on virtual array Technique

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IEICE TRANSACTIONS ON COMMUNICATIONS 2015年第5期E98B卷 814-823页

作者： Phommasack, Phavanhna Karasawa, Yoshio Univ Electrocommun Chofu Tokyo 1828585 Japan

The present paper proposes a method for simultaneously estimating the direction of arrival (DOA) and delay of multipath signals through the virtual array reception of broadband signals. In order to confirm the principles behind the proposed method, a broadband signal of 42MHz, equivalent to seven adjacent TV channels being transmitted from the Tokyo Skytree, was acquired and stored in a personal computer as the reception signal, which acts as reference signal. In addition, a multipath signal with DOA and delay was generated using a personal computer. Signal processing revealed that DOA and delay could be identified correctly. Finally, a multipath propagation analysis is conducted for an actual outdoor propagation environment as a demonstration of the proposed method.

关键词： propagation measurement virtual array DOA delay

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Investigation of virtual array Antennas With Adaptive Element Locations and Polarization Using Parabolic Reflector Antennas

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IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION 2013年第2期61卷 688-699页

作者： Pour, Zahra Allahgholi Shafai, Lotfollah Univ Manitoba Dept Elect & Comp Engn Winnipeg MB R3T 5V6 Canada

A novel multi-phase center parabolic reflector antenna is investigated that utilizes a single hardware system to displace the antenna phase center location electronically in any direction, while generating identical broadside secondary radiation patterns at the far-field region to convert the reflector antenna into a virtual array. The primary feed is a dual-mode circular waveguide operating at the TE11 and TE21 type modes. The combination of these modes with different polarizations, amplitude ratios, and phase differences are considered. It is shown that the phase center location of the antenna can be displaced from the physical center of its geometry by changing the excitation amplitude and phase of each mode, and more importantly by employing different mode orientations. This results in a virtual array antenna with element locations that can be displaced in any direction, depending on the polarization of each mode, by a simple signal processing procedure without mechanically moving the antenna itself. The antenna developed using this technique has potential applications as a transceiver antenna in precise positioning systems, radars with moving platforms, and virtual smart antennas. The operating frequency is 10 GHz. The proposed multi-phase center virtual antenna concept is verified experimentally exhibiting excellent agreement with the numerical results.

关键词： Dual-mode circular waveguide feeds parabolic reflectors phase center polarization virtual array

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Semiconductor Sensor virtual array: Gas Detection Strategy in Internet of Things to Suppress Humidity Interference

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IEEE INTERNET OF THINGS JOURNAL 2024年第3期11卷 4934-4941页

作者： Ji, Hanyang Zhu, Hongmin Zhang, Renze Zhang, Shouwen Yuan, Zhenyu Meng, Fanli Northeastern Univ Coll Informat Sci & Engn Shenyang 110819 Peoples R China Northeastern Univ Coll Informat Sci & Engn Natl Frontiers Sci Ctr Ind Intelligence & Syst Opt State Key Lab Synthet Automat Proc Ind Shenyang 110819 Peoples R China Northeastern Univ Key Lab Data Analyt & Optimizat Smart Ind Minist Educ Shenyang 110819 Peoples R China Hebei Key Lab Micronano Precis Opt Sensing & Measu Qinhuangdao 066004 Peoples R China

Semiconductor sensors are widely used in gas monitoring of living and industrial environment in the Internet of Things, but humidity interference affects the detection accuracy. The virtual array is proposed as a novel measurement method. It has the advantages of humidity suppression, low-power consumption, and simple structure, which is conducive to further research and development of intelligent sensing device with integrated sensing, memory, and computing in the Internet of Things. This method adopts the heating mode of cyclic variable temperature and extracts the stable conductance values at different temperatures as the response. In the design of a virtual array, the response difference between reducing gas and humidity at different temperatures is used to overcome humidity interference. The output information is expanded from the perspective of measurement so that the humidity interference quantity is characterized simultaneously. Cyclic variable heating voltage is applied to the sensor to obtain the response value under different heating conditions. The response values under high and low levels are displayed as coordinates in the 2-D plane. Samples with reducing gas and humidity are satisfied by the law of the approximate vector sum of their one-component responses. This method was not only confirmed in the main experiment of toluene detection but also in the detection of butanone and the detection of toluene by multiple sensors.

关键词： Anti-humidity Internet of Things semiconductor gas sensors virtual array

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A Novel High-Resolution Propagation Measurement Scheme for Indoor Terrestrial TV Signal Reception Based on Two-Dimensional virtual array Technique

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IEICE TRANSACTIONS ON COMMUNICATIONS 2013年第4期E96B卷 986-993页

作者： Morokuma, Kazuo Takemoto, Atsushi Karasawa, Yoshio Univ Electrocommun UEC Tokyo Chofu Tokyo 1828585 Japan

We propose a novel propagation measurement scheme for terrestrial TV signal indoor reception based on a virtual array technique. The system proposed in this paper carries out two-branch recording of target signals and the reference signal. By using the signal phase reference in the reference signal, we clarify the spatial propagation characteristics obtained from the two-dimensional virtual array outputs. Outdoor measurements were performed first to investigate the validity of the proposed measurement system. The results confirm its effectiveness in accurately determining the direction-of-arrival (DOA). We then investigated the propagation characteristics in an indoor environment. The angular spectrum obtained showed clear wave propagation structure. Thus, our proposed system is promising as a very accurate measurement tool for indoor propagation analysis.

关键词： indoor propagation multipath propagation direction finding MUSIC algorithm virtual array

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array Interpolation Using Covariance Matrix Completion of Minimum-Size virtual array

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IEEE SIGNAL PROCESSING LETTERS 2017年第7期24卷 1063-1067页

作者： Hosseini, Seyed MohammadReza Sebt, Mohammad Ali KN Toosi Univ Technol Dept Elect Engn Tehran *** Iran

Sparse arrays increase aperture and resolution capability for direction-of-arrival estimation. Spatial smoothing step in coarrayMUSIC algorithm prevents us from using the full coarray;so, there is a limitation for aperture Na and degrees of freedom that are determined by minimum redundancy arrays. Interpolation methods can reduce this limitation and make it possible to use the full coarray of partially augmentable arrays. In interpolation methods based on matrix completion techniques, we should complete an N-a x N-a Toeplitzmatrix. For this purpose, a semidefinite programming (SDP) with O(Na-6) complexity should be solved. In this letter, we introduce a set that contains arrays that have the equal aperture with original array and have filled coarray. By selecting the array that have minimum number of sensors in this set, we formulate a new structured matrix completion problem. Numerical examples indicate that the proposed structured matrix completion not only decreases the complexity of SDP problem but also, in many instances, increases the estimation accuracy and probability of resolution.

关键词： Direction-of-arrival (DOA) interpolation matrix completion sparse arrays virtual array

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