To see the other types of publications on this topic, follow the link: Signal beamforming.
Journal articles on the topic 'Signal beamforming'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Signal beamforming.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Wang, Yiming, and Yangfan Liu. "A directional active noise control algorithm based on all-pass/minimum phase decomposition." Journal of the Acoustical Society of America 152, no. 4 (2022): A99. http://dx.doi.org/10.1121/10.0015672.
Full textAbstract:
In this paper, we propose the design of a directional active noise control (ANC) system, which can suppress the noise coming from one specific direction without affecting the noise coming from other directions. The proposed directional ANC system integrates the sound extraction feature of a beamforming system with the active noise canceling feature of an ANC system. Instead of using the signals collected by the reference microphones as the reference signals directly, the directional ANC system uses the signal filtered by carefully designed minimum phase beamforming filters as the new reference signal, in which the noise signal coming from the look-direction of the beamformer is enhanced and at the same time noise signals coming from other directions are suppressed. Usually, the filtered signal of a beamforming system cannot be used as the reference signal of an ANC system because the delays introduced by the beamforming process degrade the performance of the ANC system. To resolve the problem, a spectral factorization technique is introduced and used to extract the minimum phase component of the beamforming filters which decreases the required delays of the beamforming system.
2
Abadi, Shima, David R. Dowling, Heechun Song, and Kevin J. Haworth. "The origins of frequency-difference and frequency-sum beamforming." Journal of the Acoustical Society of America 155, no. 3_Supplement (2024): A125. http://dx.doi.org/10.1121/10.0027033.
Full textAbstract:
Beamforming the signals recorded by an array enables the determination of sound source location(s) or the arrival directions of ray paths between a sound source and the receiving array. Frequency-difference and frequency-sum beamforming are beamforming techniques that provide out-of-band information from in-band signal frequencies. Interestingly, the out-of-band frequencies can be chosen by the user, within limits set by the signal recordings, to achieve desired properties of the beamformed output, such as: increased resolution, reduced sidelobes, or greater robustness to random scattering. Both techniques are general and are not limited to any particular acoustic environment, frequency range, or array geometry. Frequency-sum beamforming, generates higher-frequency information from lower frequency signal components, enhancing beamforming results in scenarios with random scattering between the source and the receivers. However, it is limited by artifacts arising from cross-terms when multiple source signals are present in the same bandwidth. Conversely, frequency-difference beamforming manufactures lower-frequency information from higher frequency signal components, effectively mitigating the impact of spatial aliasing in situations where the receiving array is sparse. This presentation delves into the origins of frequency-difference and frequency-sum beamforming, presents the fundamental mathematics underlying their algorithms, and showcases their performance via simulations and experimental results. [Work supported by ONR.]
3
Kiong, Tiong Sieh, S. Balasem Salem, Johnny Koh Siaw Paw, K. Prajindra Sankar, and Soodabeh Darzi. "Minimum Variance Distortionless Response Beamformer with Enhanced Nulling Level Control via Dynamic Mutated Artificial Immune System." Scientific World Journal 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/164053.
Full textAbstract:
In smart antenna applications, the adaptive beamforming technique is used to cancel interfering signals (placing nulls) and produce or steer a strong beam toward the target signal according to the calculated weight vectors. Minimum variance distortionless response (MVDR) beamforming is capable of determining the weight vectors for beam steering; however, its nulling level on the interference sources remains unsatisfactory. Beamforming can be considered as an optimization problem, such that optimal weight vector should be obtained through computation. Hence, in this paper, a new dynamic mutated artificial immune system (DM-AIS) is proposed to enhance MVDR beamforming for controlling the null steering of interference and increase the signal to interference noise ratio (SINR) for wanted signals.
4
Lee, Jeung-Hoon, Yongsung Park, and Peter Gerstoft. "Compressive frequency-difference direction-of-arrival estimation." Journal of the Acoustical Society of America 154, no. 1 (2023): 141–51. http://dx.doi.org/10.1121/10.0020053.
Full textAbstract:
Direction-of-arrival estimation is difficult for signals spatially undersampled by more than half the wavelength. Frequency-difference beamforming [Abadi, Song, and Dowling (2012). J. Acoust. Soc. Am. 132, 3018–3029] offers an alternative approach to avoid such spatial aliasing by using multifrequency signals and processing them at a lower frequency, the difference-frequency. As with the conventional beamforming method, lowering the processing frequency sacrifices spatial resolution due to a beam broadening. Thus, unconventional beamforming is detrimental to the ability to distinguish between closely spaced targets. To overcome spatial resolution deterioration, we propose a simple yet effective method by formulating the frequency-difference beamforming as a sparse signal reconstruction problem. Similar to compressive beamforming, the improvement (compressive frequency-difference beamforming) promotes sparse nonzero elements to obtain a sharp estimate of the spatial direction-of-arrival spectrum. Analysis of the resolution limit demonstrates that the proposed method outperforms the conventional frequency-difference beamforming in terms of separation if the signal-to-noise ratio exceeds 4 dB. Ocean data from the FAF06 experiment support the validity.
5
Su, Xiruo, Qiuyan Miao, Xinglin Sun, Haoran Ren, Lingyun Ye, and Kaichen Song. "An Optimal Subspace Deconvolution Algorithm for Robust and High-Resolution Beamforming." Sensors 22, no. 6 (2022): 2327. http://dx.doi.org/10.3390/s22062327.
Full textAbstract:
Utilizing the difference in phase and power spectrum between signals and noise, the estimation of direction of arrival (DOA) can be transferred to a spatial sample classification problem. The power ratio, namely signal-to-noise ratio (SNR), is highly required in most high-resolution beamforming methods so that high resolution and robustness are incompatible in a noisy background. Therefore, this paper proposes a Subspaces Deconvolution Vector (SDV) beamforming method to improve the robustness of a high-resolution DOA estimation. In a noisy environment, to handle the difficulty in separating signals from noise, we intend to initial beamforming value presets by incoherent eigenvalue in the frequency domain. The high resolution in the frequency domain guarantees the stability of the beamforming. By combining the robustness of conventional beamforming, the proposed method makes use of the subspace deconvolution vector to build a high-resolution beamforming process. The SDV method is aimed to obtain unitary frequency matrixes more stably and improve the accuracy of signal subspaces. The results of simulations and experiments show that when the input SNR is less than −27 dB, signals of decomposition differ unremarkably in the subspace while the SDV method can still obtain clear angles. In a marine background, this method works well in separating the noise and recruiting the characteristics of the signal into the DOA for subsequent processing.
6
Guo, Ming, Zixuan Shen, Yuee Zhou, and Shenghui Li. "Improved Convolutional Neural Network for Wideband Space-Time Beamforming." Electronics 13, no. 13 (2024): 2492. http://dx.doi.org/10.3390/electronics13132492.
Full textAbstract:
Wideband beamforming technology is an effective solution in millimeter-wave (mmWave) massive multiple-input multiple-output (MIMO) systems to compensate for severe path loss through beamforming gain. However, traditional adaptive wideband digital beamforming (AWDBF) algorithms suffer from serious performance degradation when there are insufficient signal snapshots, and the training process of the existing neural network-based wideband beamforming network is slow and unstable. To address the above issues, an AWDBF method based on the convolutional neural network (CNN) structure, the improved wideband beamforming prediction network (IWBPNet), is proposed. The proposed method increases the network’s feature extraction capability for array signals through deep convolutional layers, thus alleviating the problem of insufficient network feature extraction capabilities. In addition, the pooling layers are introduced into the IWBPNet to solve the problem that the fully connected layer of the existing neural network-based wideband beamforming algorithm is too large, resulting in slow network training, and the pooling operation increases the generalization ability of the network. Furthermore, the IWBPNet has good wideband beamforming performance with low signal snapshots, including beam pattern performance and output signal-to-interference-plus-noise ratio (SINR) performance. The simulation results show that the proposed algorithm has superior performance compared with the traditional wideband beamformer with low signal snapshots. Compared with the wideband beamforming algorithm based on the neural network, the training time of IWBPNet is only 10.6% of the original neural network-based wideband beamformer, while the beamforming performance is slightly improved. Simulations and numerical analyses demonstrate the effectiveness and superiority of the proposed wideband beamformer.
7
Lin, Yue, Di Jiang, Yuan Chen, Xiang Li, and Qi Qiu. "Reconfigurable Microwave Multi-Beamforming Based on Optical Switching and Distributing Network." Photonics 11, no. 1 (2024): 65. http://dx.doi.org/10.3390/photonics11010065.
Full textAbstract:
Optical beamforming in microwave photonics is promising for supporting broadband wireless communications. However, the current optical beamforming lacks freedom because of the fixed connection between radio frequency (RF) signal and antenna elements (AEs). This manuscript tackles this challenge by proposing a dynamical optical beamforming architecture that reconfigures the antenna subarray for signal transmission depending on the number of signals to be transmitted. The proposed architecture employs an optical switching and distributing network (SDN) to realize a flexible connection between signals and AEs. An instance of the proposed architecture in photonic integrated circuits, which enables three working modes and transmits four RF signals through sixteen AEs, was presented and numerically simulated. The optical field distribution and beam pattern plots illustrated the operational principle and validated the feasibility of the proposed SDN architecture. Furthermore, the impact of the introduced architecture on the signal amplitude–phase consistency and the comparison of the proposed dynamic architecture and conventional fixe architectures are analyzed and discussed. The results indicate that the proposed architecture exhibits variable beamforming gain with lower hardware complexity.
8
Lan, Hualin, Xueqi Zhang, Ruonan Li, Suyu Jin, and Na Li. "Assessment of multi-target distinguishing using deconvolved conventional beamforming." MATEC Web of Conferences 283 (2019): 04005. http://dx.doi.org/10.1051/matecconf/201928304005.
Full textAbstract:
Multi-target distinguishing based on beamforming is a popular topic in array signal processing. Conventional beamforming as a frequently used method is robust but constrained by the Rayleigh limit. Deconvolved conventional beamforming is a better choice since point scattering function could be derived by deconvolution based on Lucy-Richardson, with narrower beam width and lower sidelobe levels. Besides, the robustness of the conventional beamforming is maintained. In this paper, a new method of combined deconvolved conventional beamforming with Dolph-Chebyshev weights is proposed. The proposed method could overcome the deficit of deconvolved conventional beamforming on low mainlobe of weak target caused by iteration. Firstly, principles of the method are given including conventional beamforming, deconvolved conventional beamforming and the proposed algorithm combined deconvolved conventional beamforming with Dolph-Chebyshev weights. Then, performance of the proposed method for bi-target signals with the equivalent strength, in terms of the effect of signal frequency on distinguishing performance of two closed spaced targets coexisted is analysed. For weak target detection existed strong interference, the superiority of the proposed algorithm is analysed. Finally, proposed method is validated with sea trial data of two ship target noise recorded by a 48-element array.
9
Zhao, Tianxiao, Chunbo Luo, Jianming Zhou, Dechun Guo, Ning Chen, and Pablo Casaseca-de-la-Higuera. "DoA Prediction Based Beamforming with Low Training Overhead for Highly-Mobile UAV Communication with Cellular Networks." Applied Sciences 10, no. 13 (2020): 4420. http://dx.doi.org/10.3390/app10134420.
Full textAbstract:
In supporting communications with unmanned aerial vehicles (UAVs) as aerial user equipments (aUEs) in cellular systems, the current beamforming schemes based on channel state estimation are facing severe challenges from the pilot contamination effect, especially in 5G and future networks where the cell size becomes small and the user density is high. Beamforming schemes based on signal direction of arrival (DoA) are regarded as a highly promising alternative to solve this problem. However, to achieve optimal performance for DoA-based beamforming, the error to DoA estimation during pilot signal intervals, caused by the high mobility of UAVs, must be addressed. In the meantime, the training overheads of traditional DoA estimation algorithms must be reduced to save the bandwidth for data communication. This paper investigates uplink beamforming performance enhancement based on signal DoA estimation to support UAV-cellular network communication. We propose a novel DoA estimation algorithm to predict angle variations during the intervals, which achieves high precision even when UAVs are at high mobility. The prediction process requires no pilot signals and enables timely adjustment of the steering vector when calculating the beamforming weight vector. The proposed algorithm contributes to the realisation of a beamforming scheme with real-time steering vector updates, which simultaneously maintains high beamforming gains and low training overheads. Simulation results show that, compared with the conventional DoA-based beamforming scheme, the proposed method yields more accurate DoA estimation output and higher gains. Furthermore, simulation experiments also suggests that applying the proposed scheme can reduce up to 100 pilot signal transmissions per second.
10
Bishop, Jordan W., Philip S. Blom, and Jeremy Webster. "Generalized least squares beamforming of infrasound data." Journal of the Acoustical Society of America 155, no. 3_Supplement (2024): A70. http://dx.doi.org/10.1121/10.0026835.
Full textAbstract:
Generalized least squares (GLS) beamforming is a method for determining the direction of arrival and trace velocity of transient infrasound signals that may be otherwise obscured by persistent, correlated background noise, such as microbaroms. This method complements the adaptive F-detector by using an estimate of the noise background to form a generalized power ratio, which is used to estimate plane wave parameters (trace velocity and back-azimuth). Using a suite of fully synthetic signals, we first investigate the resolving power of the GLS estimator as a function of signal to noise ratio compared with a conventional, non-adaptive estimator. Fstatistic and plane wave parameter estimates will then be compared between GLS beamforming, conventional Bartlett beamforming, Capon beamforming, and the MUSIC algorithm. Recorded infrasonic signals from the Forensics Surface Experiment, where a persistent signal was observed from the south, will then be used to evaluate the GLS method. Initial analyses suggest that GLS beamforming results in a lower F-statistic during noise regions and a higher F-statistic value for transient signals compared to the Bartlett beam. Algorithmically determining an optimal window to characterize the background noise presents a significant challenge and different approaches will be discussed.
11
Wang, Jianling. "IRS Backscatter-Assisted Security Transmission against Proactive Eavesdropping." Wireless Communications and Mobile Computing 2022 (May 5, 2022): 1–10. http://dx.doi.org/10.1155/2022/4553805.
Full textAbstract:
In this paper, we consider the IRS backscatter-assisted physical layer security, aimed at countering smart eavesdroppers capable of sending jamming signals. Specifically, the eavesdropper increases the eavesdropping rate by sending jamming signals and is able to adjust the transmission strategy according to the received beamforming. By using IRS backscatter communication, the jamming signal sent by the eavesdropper is converted into a useful signal and transmitted. By designing the beamforming of the base station and the IRS phase shift matrix, we established the original optimization problem. Since the eavesdropper’s sending strategy is adjusted according to the received signal, we transform the original problem into two subproblems. In the first subproblem, we obtain the eavesdropper’s transmit beamforming; in the second subproblem, we optimize the transmit beam alternately with the IRS phase shift matrix. Simulation results demonstrate the superiority of our proposed scheme.
12
Yang, Jian, Xinxin Liu, Yuwei Tu, and Weixing Li. "Robust Adaptive Beamforming Algorithm for Sparse Subarray Antenna Array Based on Hierarchical Weighting." Micromachines 13, no. 6 (2022): 859. http://dx.doi.org/10.3390/mi13060859.
Full textAbstract:
Sparse antenna arrays based on subarrays have more and more broad application prospects for the limitation of array space, real-time algorithm and hardware costs. Aiming at the beamforming technology of sparse antenna arrays based on subarrays, this paper proposes a robust adaptive beamforming algorithm based on hierarchical weighting. The algorithm performs conventional beamforming to calculate the weights of each element in the subarray, then the synthetic signals output by each subarray are used as sparse array metadata. The Interference-plus-Noise Covariance Matrix (INCM) is reconstructed by integration in two-dimensional space, and a convex optimization model of a multi-constraint array containing the signal pointing error was established to estimate the real guide vector. Finally, using the reconstructed INCM and the estimation of the guide vector, we obtain a weighted vector between the subarrays and output signal for the whole array. The simulation results show that the proposed algorithm has better Signal-to-Interference-and-Noise Ratio (SINR) and robustness compared with other algorithms for sparse subarray antenna array beamforming.
13
Leng, Kaijing, and Leilei Deng. "Direction of arrival and target scale estimation based on split beamforming algorithm." Journal of Physics: Conference Series 2290, no. 1 (2022): 012110. http://dx.doi.org/10.1088/1742-6596/2290/1/012110.
Full textAbstract:
Abstract Based on the theory of split beamforming algorithm and the experimental data collected by circular array, this paper analyzes the characteristics of DOA and target size estimation. In this paper, the signal receiving model of planar circular array and the split beamforming algorithm are studied. Then, based on the data collected from the lake experiment, the DOA estimation results of conventional beamforming algorithm, multiple signal classification algorithm and split beamforming algorithm are analyzed, and the target scale estimation results of split beamforming algorithm is analyzed. The experimental data analysis shows that the split beamforming algorithm has good direction finding stability, and the target scale estimation error based on the split beamforming algorithm is small.
14
Zhang, Ce, Cheng Wei Lee, and Wei Ma. "Effects of Acoustic Shielding on Beamforming for Rotating Sound Source Localization." Acoustics 7, no. 1 (2025): 8. https://doi.org/10.3390/acoustics7010008.
Full textAbstract:
Beamforming for rotating sound source localization (denoted by rotating beamforming) is widely used in engineering nowadays. Acoustic shielding, such as shafts and covers, is typically employed in the practical measurement of rotating source localization. Acoustic shielding blocks the signal propagation between rotating sources and the array, and thus affects the performance of rotating beamforming. However, the detailed effects of acoustic shielding on rotating beamforming are still unclear. In this study, the blocking rate that represents the degree of signal propagation path blockage is defined first. The effects of acoustic shielding on rotating beamforming are then investigated in simulations. Finally, these effects are verified by experiments. According to the results of the simulation and experiments, rotating beamforming can still localize rotating sources, as long as the signal propagation path is not completely blocked. However acoustic shielding decreases sound intensity accuracy, especially when the blocking rate is larger than 50%. When acoustic shielding is employed, the ability of rotating beamforming to compensate for Doppler effects weakens.
15
Zhang, Yinan, Guangxue Wang, Shirui Peng, Yi Leng, Guowen Yu, and Bingqie Wang. "Near-Field Beamforming Algorithms for UAVs." Sensors 23, no. 13 (2023): 6172. http://dx.doi.org/10.3390/s23136172.
Full textAbstract:
This study presents three distributed beamforming algorithms to address the challenges of positioning and signal phase errors in unmanned aerial vehicle (UAV) arrays that hinder effective beamforming. Firstly, the array’s received signal phase error model was analyzed under near-field conditions. In the absence of navigation data, a beamforming algorithm based on the Extended Kalman Filter (EKF) was proposed. In cases where navigation data were available, Taylor expansion was utilized to simplify the model, the non-Gaussian noise of the compensated received signal phase was approximated to Gaussian noise, and the noise covariance matrix in the Kalman Filter (KF) was estimated. Then, a beamforming algorithm based on KF was developed. To further estimate the Gaussian noise distribution of the received signal phase, the noise covariance matrix was iteratively estimated using unscented transformation (UT), and here, a beamforming algorithm based on the Unscented Kalman Filter (UKF) was proposed. The proposed algorithms were validated through simulations, illustrating their ability to suppress the malign effects of errors on near-field UAV array beamforming. This study provides a reference for the implementation of UAV array beamforming under varying conditions.
16
Han, Yubing, and Jian Wang. "Adaptive Beamforming Based on Compressed Sensing with Smoothedl0Norm." International Journal of Antennas and Propagation 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/959856.
Full textAbstract:
An adaptive beamforming based on compressed sensing with smoothedl0norm for large-scale sparse receiving array is proposed in this paper. Because of the spatial sparsity of the arriving signal, compressed sensing is applied to sample received signals with a sparse array and reduced channels. The signal of full array is reconstructed by using a compressed sensing reconstruction method based on smoothedl0norm. Then an iterative linearly constrained minimum variance beamforming algorithm is adopted to form antenna beam, whose main lobe is steered to the desired direction and nulls to the directions of interferences. Simulation results and Monte Carlo analysis for linear and planar arrays show that the beam performances of our proposed adaptive beamforming are similar to those of full array antenna.
17
Drew, Jordan A., and W. Owen Brimijoin. "Negative impacts from latency masked by noise in simulated beamforming." PLOS ONE 16, no. 7 (2021): e0254119. http://dx.doi.org/10.1371/journal.pone.0254119.
Full textAbstract:
Those experiencing hearing loss face severe challenges in perceiving speech in noisy situations such as a busy restaurant or cafe. There are many factors contributing to this deficit including decreased audibility, reduced frequency resolution, and decline in temporal synchrony across the auditory system. Some hearing assistive devices implement beamforming in which multiple microphones are used in combination to attenuate surrounding noise while the target speaker is left unattenuated. In increasingly challenging auditory environments, more complex beamforming algorithms are required, which increases the processing time needed to provide a useful signal-to-noise ratio of the target speech. This study investigated whether the benefits from signal enhancement from beamforming are outweighed by the negative impacts on perception from an increase in latency between the direct acoustic signal and the digitally enhanced signal. The hypothesis for this study is that an increase in latency between the two identical speech signals would decrease intelligibility of the speech signal. Using 3 gain / latency pairs from a beamforming simulation previously completed in lab, perceptual thresholds of SNR from a simulated use case were obtained from normal hearing participants. No significant differences were detected between the 3 conditions. When presented with 2 copies of the same speech signal presented at varying gain / latency pairs in a noisy environment, any negative intelligibility effects from latency are masked by the noise. These results allow for more lenient restrictions for limiting processing delays in hearing assistive devices.
18
Fan, Long, Lei Xie, Wenhui Zhou, Chuyu Wang, Yanling Bu, and Sanglu Lu. "Beamforming for Sensing: Hybrid Beamforming based on Transmitter-Receiver Collaboration for Millimeter-Wave Sensing." Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies 8, no. 2 (2024): 1–27. http://dx.doi.org/10.1145/3659619.
Full textAbstract:
Previous mmWave sensing solutions assumed good signal quality. Ensuring an unblocked or strengthened LoS path is challenging. Therefore, finding an NLoS path is crucial to enhancing perceived signal quality. This paper proposes Trebsen, a Transmitter-REceiver collaboration-based Beamforming scheme SENsing using commercial mmWave radars. Specifically, we define the hybrid beamforming problem as an optimization challenge involving beamforming angle search based on transmitter-receiver collaboration. We derive a comprehensive expression for parameter optimization by modeling the signal attenuation variations resulting from the propagation path. To comprehensively assess the perception signal quality, we design a novel metric perceived signal-to-interference-plus-noise ratio (PSINR), combining the carrier signal and baseband signal to quantify the fine-grained sensing motion signal quality. Considering the high time cost of traversing or randomly searching methods, we employ a search method based on deep reinforcement learning to quickly explore optimal beamforming angles at both transmitter and receiver. We implement Trebsen and evaluate its performance in a fine-grained sensing application (i.e., heartbeat). Experimental results show that Trebsen significantly enhances heartbeat sensing performance in blocked or misaligned LoS scenes. Comparing non-beamforming, Trebsen demonstrates a reduction of 23.6% in HR error and 27.47% in IBI error. Moreover, comparing random search, Trebsen exhibits a 90% increase in search speed.
19
Qiu, Yanping, Siyu Gao, Qian Chen, Gaoying Zhang, and Yinquan Zhang. "Beamforming based on DtN mapping." Journal of Physics: Conference Series 2939, no. 1 (2025): 012005. https://doi.org/10.1088/1742-6596/2939/1/012005.
Full textAbstract:
Abstract At present, the conventional beamforming is carried out by using the signal obtained from the pressure hydrophone, which is less than the vector hydrophone in the angular resolution. However, it is difficult for the vector hydrophone to make its application. Researchers have tried to use differential pressure hydrophones to increase the angular resolution, but it requires that the element spacing be much smaller than the wavelength. This paper proposes an idea to realize the reconstruction of acoustic pressure signals into the high-order gradient signal of acoustic pressure, which doesn’t require the element spacing to be much smaller than the wavelength. The method mainly uses the Rayleigh hypothesis, which considers that the elements are connected to each point. The establishment of DtN mapping matrix is for achieving high-order beamforming. The beamforming based on DtN mapping has a higher directivity index and orientation accuracy than conventional beamforming. It can also realize the superdirectivity of the end-direction.
20
Idris, Olayinka Oduola. "Introduction to Real-Time Signal Processing Algorithms for 5G and Beyond: Beamforming and Channel Estimation Strategies." International Journal of Education, Management, and Technology 3, no. 2 (2025): 439–56. https://doi.org/10.58578/ijemt.v3i2.5425.
Full textAbstract:
The emergence of 5G and the exploration of beyond-5G (B5G) and 6G networks have introduced new paradigms in wireless communication, characterized by ultra-high data rates, massive connectivity, and ultra-low latency. Real-time signal processing has become a critical enabler of these technologies, particularly in the areas of beamforming and channel estimation. Beamforming enables the focused transmission of signals, improving signal strength and reducing interference, while channel estimation provides essential knowledge of the transmission environment, allowing for dynamic adaptation of communication strategies. This paper provides a comprehensive review of beamforming and channel estimation strategies in 5G, with a focus on their real-time implementation. It explores various types of beamforming—analog, digital, and hybrid—as well as channel estimation methods including pilot-based, blind, and semi-blind techniques. The integration of these methods is also examined, along with real-time algorithmic approaches such as LMS, RLS, Kalman filtering, and machine learning models. Applications across massive MIMO, millimeter-wave communication, and vehicular networks are discussed. Finally, the paper outlines future research directions, emphasizing the growing role of AI, machine learning, and emerging quantum computing technologies in optimizing real-time signal processing for 6G and beyond.
21
Yang, Ze-Kun, Cong-Cong Cheng, Zhaobin Wang, and Hong-Wei Yang. "Detection of breast cancer using ultra-wide band beamforming algorithm." Modern Physics Letters B 31, no. 09 (2017): 1750091. http://dx.doi.org/10.1142/s0217984917500919.
Full textAbstract:
This paper is based on the general principle of beamforming algorithm of array signal processing. It gives a kind of high precision adaptive time-domain beamforming algorithm, uses ultra-wide band (UWB) microwave signal as an emission source applied to the human body in early breast cancer detection. In this paper, we build a two-dimensional, semicircle breast tissue model, use numerical simulation with finite-difference time-domain (FDTD) method for detection. The result shows the superiority of beamforming algorithm compared with that of confocal imaging algorithms and beamforming algorithms, especially to the Capon beamforming algorithm.
22
Bi, Yang, Xi’an Feng, and Yangmei Zhang. "Optimized Sonar Broadband Focused Beamforming Algorithm." Algorithms 12, no. 2 (2019): 33. http://dx.doi.org/10.3390/a12020033.
Full textAbstract:
Biases of initial direction estimation and focusing frequency selection affect the final focusing effect and may even cause algorithm failure in determining the focusing matrix in the coherent signal–subspace method. An optimized sonar broadband focused beamforming algorithm is proposed to address these defects. Initially, the robust Capon beamforming algorithm was used to correct the focusing matrix, and the broadband signals were then focused on the optimal focusing frequency by the corrected focusing matrix such that the wideband beamforming was transformed into a narrowband problem. Finally, the focused narrowband signals were beamformed by the second-order cone programming algorithm. Computer simulation results and water pool experiments verified that the proposed algorithm provides a good performance.
23
Cantero-Chinchilla, Sergio, Gerardo Aranguren, Muhammad Khalid Malik, Josu Etxaniz, and Federico Martín de la Escalera. "An Empirical Study on Transmission Beamforming for Ultrasonic Guided-Wave Based Structural Health Monitoring." Sensors 20, no. 5 (2020): 1445. http://dx.doi.org/10.3390/s20051445.
Full textAbstract:
The development of reliable structural health monitoring techniques is enabling a healthy transition from preventive to condition-based maintenance, hence leading to safer and more efficient operation of different industries. Ultrasonic guided-wave based beamforming is one of the most promising techniques, which supports the monitoring of large thin-walled structures. However, beamforming has been typically applied to the post-processing stage (also known as virtual or receiver beamforming) because transmission or physical beamforming requires complex hardware configurations. This paper introduces an electronic structural health monitoring system that carries out transmission beamforming experiments by simultaneously emitting and receiving ultrasonic guided-waves using several transducers. An empirical characterization of the transmission beamforming technique for monitoring an aluminum plate is provided in this work. The high signal-to-noise ratio and accurate angular precision of the physical signal obtained in the experiments suggest that transmission beamforming can increase the reliability and robustnessof this monitoring technique for large structures and in real-world noisy environments.
24
Warhade, Bhagyashri, and Rupali Patil. "Millimeter Wave Massive MIMO systems using Hybrid Beamforming." International Journal of Electrical and Electronics Research 12, no. 3 (2024): 957–62. http://dx.doi.org/10.37391/ijeer.120329.
Full textAbstract:
The goal of next-generation wireless systems is to support many users by achieving higher data rates and reduced latency. Multiple input and multiple output systems (MIMO) are utilized in order to achieve high data rates. Multiple antennas are employed by Massive MIMO systems in both the transmitter along with the receiver. A signal processing method known as beamforming is used on several transmitting and receiving stations in order to deliver and receive multiple messages at once. To increase spectral efficiency, hybrid beamforming using a uniform rectangular antenna array is used in this research work. The results of hybrid beamforming using different numbers of antennas are compared with those of fully digital beamforming. A comparison between signal-to-noise (SNR) and bit error rate (BER) is performed. Comparing hybrid beamforming to fully digital beamforming, simulation findings show that hybrid beamforming reduces computing complexity due to reduced number of RF links. Also observed that the spectral efficiency rises with an increase in the quantity of transmitting antennas.
25
Fadhil, Mohammed, Nor Fadzilah Abdullah, Mahamod Ismail, Rosdiadee Nordin, Cebrail Ciftlikli, and Musaab Al-Obaidi. "Maximizing signal to leakage ratios in MIMO BCH cooperative beamforming scheme." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 5 (2019): 3701. http://dx.doi.org/10.11591/ijece.v9i5.pp3701-3713.
Full textAbstract:
Beamforming (BF) technique in cooperative multiple input multiple output (MIMO) antenna arrays improves signal to noise ratio (SNR) of the intended user. The challenge is to design transmit beamforming vectors for every user while limiting the co-channel interference (CCI) from other users. In this paper, we proposed cooperative beamforming based on Signal-to-Leakage Ratio (SLR) to exploit the leakage power as a useful power in the second time slot after user cooperation, for this purpose successive interference cancellation (SIC) is employed in each user to separate the leakage signal from the desired signal. Without increasing the complexity, Maximizing Signal-to-Leakage Ratio (SLR) subject to proposed power constraint instead of a unity norm is the way to achieve extra leakage power. To reduce the erroneous, Bose–Chaudhuri–Hocquenghem (BCH) codes employed in Beamforming of (SIC) cooperative scheme BF(CS-SIC-BCH). Maximum-likelihood (ML) estimator method is used at each user receiver. Simulation results show that the performance of the proposed scheme BF (CS-SIC-BCH) over Rayleigh and Rician fading channel is significantly better than the performance beamforming based on SLR in Non-cooperative system. More specifically to achieve a BER of about the required SNR for the proposed scheme is about 1 dB less than the Non-cooperative system.
26
Qian, Si Chong, and Yang Xiang. "The Relationship between Frequency Domain Blind Source Separation and Frequency Domain Adaptive Beamformer." Applied Mechanics and Materials 490-491 (January 2014): 654–62. http://dx.doi.org/10.4028/www.scientific.net/amm.490-491.654.
Full textAbstract:
As two important methods of array signal processing, blind source separation and beamforming can extract the target signal and suppress interference by using the received information of the array element. In the case of convolution mixture of sources, frequency domain blind source separation and frequency domain adaptive beamforming have similar signal model. To find the relationship between them, comparison between the minimization of the off-diagonal components in the BSS update equation and the minimization of the mean square error in the ABF had been made from the perspective of mathematical expressions, and find that the unmixing matrix of the BSS and the filter coefficients of the ABF converge to the same solution in the mean square error sense under the condition that the two source signals are ideally independent. With MATLAB, the equivalence in the frequency domain have been verified and the causes affecting separation performance have been analyzed, which was achieved by simulating instantaneous and convolution mixtures and separating mixture speech in frequency-domain blind source separation and frequency domain adaptive beamforming way.
27
Xiao, Yuteng, Jihang Yin, Honggang Qi, Hongsheng Yin, and Gang Hua. "MVDR Algorithm Based on Estimated Diagonal Loading for Beamforming." Mathematical Problems in Engineering 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/7904356.
Full textAbstract:
Beamforming algorithm is widely used in many signal processing fields. At present, the typical beamforming algorithm is MVDR (Minimum Variance Distortionless Response). However, the performance of MVDR algorithm relies on the accurate covariance matrix. The MVDR algorithm declines dramatically with the inaccurate covariance matrix. To solve the problem, studying the beamforming array signal model and beamforming MVDR algorithm, we improve MVDR algorithm based on estimated diagonal loading for beamforming. MVDR optimization model based on diagonal loading compensation is established and the interval of the diagonal loading compensation value is deduced on the basis of the matrix theory. The optimal diagonal loading value in the interval is also determined through the experimental method. The experimental results show that the algorithm compared with existing algorithms is practical and effective.
28
Liu, Zhuoran, Quan Tao, Wanzhong Sun, and Xiaomei Fu. "Deconvolved Fractional Fourier Domain Beamforming for Linear Frequency Modulation Signals." Sensors 23, no. 7 (2023): 3511. http://dx.doi.org/10.3390/s23073511.
Full textAbstract:
To estimate the direction of arrival (DOA) of a linear frequency modulation (LFM) signal in a low signal-to-noise ratio (SNR) hydroacoustic environment by a small aperture array, a novel deconvolved beamforming method based on fractional Fourier domain delay-and-sum beamforming (FrFB) was proposed. Fractional Fourier transform (FrFT) was used to convert the received signal into the fractional Fourier domain, and delay-and-sum beamforming was subsequently performed. Noise resistance was acquired by focusing the energy of the LFM signal distributed in the time–frequency domain. Then, according to the convolution structure of the FrFB complex output, the influence of the fractional Fourier domain complex beam pattern was removed by deconvolution, and the target spatial distribution was restored. Therefore, an improved spatial resolution of DOA estimation was obtained without increasing the array aperture. The simulation and experimental results show that, with a small aperture array at low SNR, the proposed method possesses higher spatial resolution than FrFB and frequency-domain deconvolved conventional beamforming.
29
Su, Hang, and Chang-Myung Lee. "Modified GSC Method to Reduce the Distortion of the Enhanced Speech Signal Using Cross-Correlation and Sidelobe Neutralization." Applied Sciences 11, no. 14 (2021): 6288. http://dx.doi.org/10.3390/app11146288.
Full textAbstract:
The generalized sidelobe canceller (GSC) method is a common algorithm to enhance audio signals using a microphone array. Distortion of the enhanced audio signal consists of two parts: the residual acoustic noise and the distortion of the desired audio signal, which means that the desired audio signal is damaged. This paper proposes a modified GSC method to reduce both kinds of distortion when the desired audio signal is a non-stationary speech signal. First, the cross-correlation coefficient between the canceling signal and the error signal of the least mean square (LMS) algorithm was added to the adaptive process of the GSC method to reduce the distortion of the enhanced signal while the energy of the desired signal frame was increased suddenly. The sidelobe pattern of beamforming was then presented to estimate the noise signal in the beamforming output signal of the GSC method. The noise component of the beamforming output signal was decreased by subtracting the estimated noise signal to improve the denoising performance of the GSC method. Finally, the GSC-SN-MCC method was proposed by merging the above two methods. The experiment was performed in an anechoic chamber to validate the proposed method in various SNR conditions. Furthermore, the simulated calculation with inaccurate noise directions was conducted based on the experiment data to inspect the robustness of the proposed method to the error of the estimated noise direction. The experiment data and calculation results indicated that the proposed method could reduce the distortion effectively under various SNR conditions and would not cause more distortion if the estimated noise direction is far from the actual noise direction.
30
Xia, Tai Wu, and Hong Jun Liu. "Multiuser Beamforming Using Weighted Orthogonal Constant Modulus Algorithm." Advanced Materials Research 204-210 (February 2011): 2162–66. http://dx.doi.org/10.4028/www.scientific.net/amr.204-210.2162.
Full textAbstract:
Beamforming is a core technique in intelligent antenna signal processing and has been receiving a prevalent focus by researchers. Common orthogonal constant modulus algorithm (OCMA) doesn’t guarantee that the weights of different beamformers converge to corresponding signals when the array of receivers takes in signals with same feature. Thereby a weighted orthogonal constant modulus algorithm (WOCMA) is proposed in which weights of different beamformers are ensured to be disparate by controlling their relevance down to a low level, which concludes different weight converges to corresponding signal. Simulation has proved that WOCMA possesses fast convergent speed and favorable facility in receiving signals.
31
Pei, Xin, Na Wang, Dan Werthimer, et al. "Design of RFSoC-based Digital Phased Array Feed (PAF) and Hybrid Architecture Beamforming System." Research in Astronomy and Astrophysics 22, no. 4 (2022): 045016. http://dx.doi.org/10.1088/1674-4527/ac56cb.
Full textAbstract:
Abstract As the number of array elements and bandwidth increase, the design challenges of the Phased Array Feed (PAF) front-end and its signal processing system increase. Aiming at the ng-PAF of the 110 m radio telescope, this article introduces the concept of fully digital receivers and attempts to use Radio Frequency System-on-Chip (RFSoC) technology to digitize close to the feed array, reduce the complexity and analog components of the front-end, and improve the fidelity of the signals. The article discusses the digital beamforming topology and designs a PAF signal processing experimental system based on RFSoC+GPU hybrid architecture. The system adopts a ZCU111 board to design RF-direct digitization and preprocessing front-end, which can sample eight signals up to 2.048 GSPS, 12 bit, channelize the signals into 1024 chunks, then reorder into four data streams and select one of the 256 MHz frequency bands to output through four 10 Gb links. A GPU server is equipped with four RTX 3090 GPUs running four HRBF_HASHPIPE instances, each receiving a 64 MHz bandwidth signal for high-throughput real-time beamforming. The experimental system uses a signal generator to emulate Sa-like signals and propagates through rod antennas, which verifies the effectiveness of the beamforming algorithm. Performance tests show that after algorithm optimization, the average processing time for a given 4 ms data is less than 3 ms in the four-GPU parallel processing mode. The RFSoC integrated design shows significant advantages in power consumption and electromagnetic radiation compared with discrete circuits according to the measurement results.
32
Ahmad, Zeeshan, Zain ul Abidin Jaffri, Najam ul Hassan, and Meng Chen. "Robust adaptive beamforming using modified constant modulus algorithms." Journal of Electrical Engineering 73, no. 4 (2022): 248–57. http://dx.doi.org/10.2478/jee-2022-0033.
Full textAbstract:
Abstract This paper addresses the self-nulling phenomenon also known as the self-cancellation in adaptive beamformers. Optimum beamforming requires knowledge of the desired signal characteristics, either its statistics, its direction-of-arrival, or its response vector. Inaccuracies in the required information lead the beamformer to attenuate the desired signal as if it were interference. Self-nulling is caused by the desired signal having large power (high SNR) relative to the interference signal in case of the minimum variance distortion less response beamformer, and low power desired signal in the case of the constant modulus algorithm (CMA) beamformer, which leads the beamformer to suppress the desired signal and lock onto the interference signal. The least-square constant modulus algorithm is a prominent blind adaptive beamforming algorithm. We propose two CMA-based algorithms which exploit the constant modularity as well as power or DOA of the desired signal to avoid self-nulling in beamforming. Simulations results verify the effectiveness of the proposed algorithms.
33
Wang, Yuzhu, Jingdong Chen, Jacob Benesty, Jilu Jin, and Gongping Huang. "Binaural Heterophasic Superdirective Beamforming." Sensors 21, no. 1 (2020): 74. http://dx.doi.org/10.3390/s21010074.
Full textAbstract:
The superdirective beamformer, while attractive for processing broadband acoustic signals, often suffers from the problem of white noise amplification. So, its application requires well-designed acoustic arrays with sensors of extremely low self-noise level, which is difficult if not impossible to attain. In this paper, a new binaural superdirective beamformer is proposed, which is divided into two sub-beamformers. Based on studies and facts in psychoacoustics, these two filters are designed in such a way that they are orthogonal to each other to make the white noise components in the binaural beamforming outputs incoherent while maximizing the output interaural coherence of the diffuse noise, which is important for the brain to localize the sound source of interest. As a result, the signal of interest in the binaural superdirective beamformer’s outputs is in phase but the white noise components in the outputs are random phase, so the human auditory system can better separate the acoustic signal of interest from white noise by listening to the outputs of the proposed approach. Experimental results show that the derived binaural superdirective beamformer is superior to its conventional monaural counterpart.
34
Xu, Bao Gen, Yi He Wan, Si Long Tang, Xue Ke Ding, and Qun Wan. "Sparsity Enhanced Beamforming in The Presence of Coherent Signals." International Journal of Applied Mathematics and Informatics 15 (November 16, 2021): 55–58. http://dx.doi.org/10.46300/91014.2021.15.9.
Full textAbstract:
In order to find the directions of coherent signals, a sparsity enhanced beam-forming method is proposed. Unlike the conventional minimum variance distortless response (MVDR) method, the minimum variance in the proposed method corresponds to the orthogonal relationship between the noise subspace and the sparse representation of the received signal vector, whereas the distortless response corresponds to the nonorthogonal relationship between the signal subspace and the sparse representation of the received signal vector. The proposed sparsity enhanced MVDR (SEMVDR) method is carried out by the iterative reweighted Lp-norm constraint minimization. for direction finding of coherent signals. Simulation results are shown that SEMVDR has better performance than the existing algorithms, such as MVDR and MUSIC, when coherent signals are present.
35
Narytnik, Teodor, Volodymyr Prysiazhnyi, Segii Kapshtyk, Maksym Denysenko, and Oleksandra Narushkevych. "IMPROVEMENT OF THE GPS SIGNAL RECEIVING RESISTANCE AGAINST ELECTROMAGNETIC INTERFERENCE, JAMMING, AND SPOOFING IS BASED ON THE USE OF THE ANTENNA ARRAY SYSTEM WITH DIGITAL BEAMFORMING AND NORAD TLE INFORMATION." Information and Telecommunication Sciences, no. 2 (December 19, 2022): 4–14. http://dx.doi.org/10.20535/2411-2976.22022.4-14.
Full textAbstract:
Background. Currently, in radio navigation systems of the various purposes, the urgent issue is stability increase of the GPS signal reception under such a jamming and spoofing types of the interference influence. In this article, the authors propose a new solution to the stability increase problem of the GPS signal reception against the jamming and spoofing interference based on the spatial selectivity of the receiver antenna. Spatial selectivity is provided through the integrated application of phased array digital beamforming technology and the use of the TLE NORAD information.
 Objective. The research goal is to develop a methodology for the integrated identification of interference sources to the radio navigation system and to increase the noise immunity for receiving radio navigation signals via spatial selection through the digital beamforming technologies utilization.
 Methods. For the research process, theoretical methods for the digital beamforming of receiving phased antenna system were used as well as the description of a two-line NORAD information element content, and calculation algorithms for the spacecraft current position.
 Results. As a result of the research, the GPS signal reception model was formed using spatial selection of GPS signal sources and interference sources, the technique to increase the stability of GPS signal reception under the jamming and spoofing types of interference influence was developed, the block diagram was suggested for the receiving device that implements the developed technique through the integrated application of the digital beamforming technology of the phased array antenna and the TLE NORAD information utilization.
 Conclusion. A conceptual idea of the method and a technical solution for the proposed method implementation were submitted. The method implementation will improve the stability of GPS signal reception under the influence of jamming and spoofing types of interference.
36
Mohammed, Fadhil, Fadzilah Abdullah Nor, Ismail Mahamod, Nordin Rosdiadee, Ciftlikli Cebrail, and Al-Obaidi Musaab. "Maximizing signal to leakage ratios in MIMO BCH cooperative beamforming scheme." International Journal of Electrical and Computer Engineering (IJECE) 9, no. 5 (2019): 3701–13. https://doi.org/10.11591/ijece.v9i5.pp3701-3713.
Full textAbstract:
Beamforming (BF) technique in cooperative multiple input multiple output (MIMO) antenna arrays improves signal to noise ratio (SNR) of the intended user. The challenge is to design transmit beamforming vectors for every user while limiting the co-channel interference (CCI) from other users. In this paper, we proposed cooperative beamforming based on Signal-to-Leakage Ratio (SLR) to exploit the leakage power as a useful power in the second time slot after user cooperation, for this purpose successive interference cancellation (SIC) is employed in each user to separate the leakage signal from the desired signal. Without increasing the complexity, Maximizing Signal-to-Leakage Ratio (SLR) subject to proposed power constraint instead of a unity norm is the way to achieve extra leakage power. To reduce the erroneous, Bose–Chaudhuri–Hocquenghem (BCH) codes employed in Beamforming of (SIC) cooperative scheme BF(CS-SIC-BCH). Maximum- likelihood (ML) estimator method is used at each user receiver. Simulation results show that the performance of the proposed scheme BF (CS-SIC- BCH) over Rayleigh and Rician fading channel is significantly better than the performance beamforming based on SLR in Non-cooperative system. More specifically to achieve a BER of about 10−4 the required SNR for the proposed scheme is about 1 dB less than the Non-cooperative system.
37
Cantero-Chinchilla, Sergio, Gerardo Aranguren, Muhammad Khalid Malik, Josu Etxaniz, and de la Escalera Federico Martín. "An empirical study on transmission beamforming for ultrasonic guided-wave based structural health monitoring." Sensors 20, no. 5 (2020): 1445. https://doi.org/10.3390/s20051445.
Full textAbstract:
The development of reliable structural health monitoring techniques is enabling a healthy transition from preventive to condition-based maintenance, hence leading to safer and more efficient operation of different industries. Ultrasonic guided-wave based beamforming is one of the most promising techniques, which supports the monitoring of large thin-walled structures. However, beamforming has been typically applied to the post-processing stage (also known as virtual or receiver beamforming) because transmission or physical beamforming requires complex hardware configurations. This paper introduces an electronic structural health monitoring system that carries out transmission beamforming experiments by simultaneously emitting and receiving ultrasonic guided-waves using several transducers. An empirical characterization of the transmission beamforming technique for monitoring an aluminum plate is provided in this work. The high signal-to-noise ratio and accurate angular precision of the physical signal obtained in the experiments suggest that transmission beamforming can increase the reliability and robustnessof this monitoring technique for large structures and in real-world noisy environments.
38
Qin, Cong, Qin Zhang, Guimei Zheng, Xiaolong Fu, and He Zheng. "Height Measurement Method for Meter-Wave Multiple Input Multiple Output Radar Based on Transmitted Signals and Receive Filter Design." Sensors 25, no. 2 (2025): 478. https://doi.org/10.3390/s25020478.
Full textAbstract:
To address the issue of low-elevation target height measurement in the Multiple Input Multiple Output (MIMO) radar, this paper proposes a height measurement method for meter-wave MIMO radar based on transmitted signals and receive filter design, integrating beamforming technology and cognitive processing methods. According to the characteristics of beamforming technology forming nulls at interference locations, we assume that the direct wave and reflected wave act as interference signals and hypothesize a direction for a hypothetical target. Then, the data received are processed to obtain the height of low-elevation-angle targets using a cognitive approach that jointly optimizes the transmitted signal and receive filter. Firstly, a signal model for the meter-wave MIMO radar based on the transmit weight matrix is established under low-elevation scenarios. Secondly, the signal model is analyzed and transformed. Thirdly, the beamforming algorithm that jointly optimizes the transmitted signals and receive filter is derived and analyzed. The algorithm maximizes the output Signal-to-Interference-plus-Noise ratio (SINR) of the receiver by designing the transmit weight matrix and receive filter. The optimization problem based on the SINR criterion is non-convex and difficult to solve. We transformed it into two sub-optimization problems and approximated the optimal solution through an alternating iteration algorithm. Finally, the proposed height measurement algorithm is compared with the Generalized Multiple Signal Classification (GMUSIC) and Maximum Likelihood (ML) height measurement algorithms. Simulation results show that the proposed algorithm can realize the height measurement of low-elevation targets. Compared to the GMUSIC and ML algorithms, it demonstrates superior performance in terms of computational complexity and multi-target elevation estimation.
39
Chen, Qian, Kai Gu, and Li Li Zhai. "Analysis of Adaptive Beamforming Based on Convex Optimization." Applied Mechanics and Materials 651-653 (September 2014): 2262–68. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.2262.
Full textAbstract:
Most of the signal in the communication system have the cyclostationary property. Many algorithms based on the cyclostationary of the signal in the array signal processing have been exploited. They can well work without knowing the steering vector of interested signal, thus they all belong to the blind algorithms. When there is cycle frequency error, a mathematical analysis of gradient decent-based algorithm is provided in this paper. It pointed out that due to the zero point effect of the sinc function, the above approach have periodic deterioration as the number of snapshot increasing. Hence, in this paper a novel robust algorithm based on conjugate gradient, which can be used to extract signals with cyclostationarity with the cycle frequency error, is proposed. Because of its fast convergence, periodic nulls can be circumvented, and the steering vector of interested signal is estimated. Then we use traditional beamformer to avoid the influence of cycle frequency error. Simulation experiments show that our new algorithm performs well under cycle frequency mismatches.
40
Van Torre, Patrick, Maria Lucia Scarpello, Luigi Vallozzi, et al. "Indoor Off-Body Wireless Communication: Static Beamforming versus Space-Time Coding." International Journal of Antennas and Propagation 2012 (2012): 1–13. http://dx.doi.org/10.1155/2012/413683.
Full textAbstract:
The performance of beamforming versus space-time coding using a body-worn textile antenna array is experimentally evaluated for an indoor environment, where a walking rescue worker transmits data in the 2.45 GHz ISM band, relying on a vertical textile four-antenna array integrated into his garment. The two transmission scenarios considered are static beamforming at low-elevation angles and space-time code based transmit diversity. Signals are received by a base station equipped with a horizontal array of four dipole antennas providing spatial receive diversity through maximum-ratio combining. Signal-to-noise ratios, bit error rate characteristics, and signal correlation properties are assessed for both off-body transmission scenarios. Without receiver diversity, the performance of space-time coding is generally better. In case of fourth-order receiver diversity, beamforming is superior in line-of-sight conditions. For non-line-of-sight propagation, the space-time codes perform better as soon as bit error rates are low enough for a reliable data link.
41
Sriploy, Pongnarin, and Monthippa Uthansakul. "Nonfeedback Distributed Beamforming Using Spatial-Temporal Extraction." International Journal of Antennas and Propagation 2016 (2016): 1–16. http://dx.doi.org/10.1155/2016/7086234.
Full textAbstract:
So far, major phase synchronization techniques for distributed beamforming suffer from the problem related to the feedback procedure as a base station has to send the feedback reference signal back to the transmitting nodes. This requires stability of communication channel or a number of retransmissions, introducing a complicated system to both transmitter and receiver. Therefore, this paper proposes an alternative technique, so-called nonfeedback beamforming, employing an operation in both space and time domains. The proposed technique is to extract a combined signal at the base station. The concept of extraction is based on solving a simultaneous linear equation without the requirement of feedback or reference signals from base station. Also, the number of retransmissions is less compared with the ones available in literatures. As a result, the transmitting nodes are of low complexity and also low power consumption. The simulation and experimental results reveal that the proposed technique provides the optimum beamforming gain. Furthermore, it can reduce Bit Error Rate to the systems.
42
Djungha Okitadiowo, John P., Aimé Lay-Ekuakille, Tommaso Isernia, Vikrant Bhateja, and Satya Prakash Singh. "Beamforming-based algorithms for recovering information from fetal electrocardiographic sensors." Acta IMEKO 12, no. 2 (2023): 1–8. http://dx.doi.org/10.21014/actaimeko.v12i2.1470.
Full textAbstract:
We deal with the extraction of the fetal electrocardiography (ECG) signal from the raw ECG signals of the mother by the beamforming- based algorithms. The foetal ECG sensors bring out signals containing information from the pregnant mother and the infant. Detailed and separate signals are already provided by the foetal ECG instruments; but for some specific studies related to the infant conditions, it is necessary to improve the quality of the signal with a dedicated processing. In this paper, four techniques, with some enhancements, are proposed to perform the processing; we have applied the following techniques: Least Mean Square (LMS) with adaptive noise cancellation technique, Discrete Wavelet Transform (DWT)-based technique, Empirical Wavelet Transform (EWT) technique, and Multiple Signal Classification (MUSIC). The LMS and the MUSIC pertain to beamforming approach. The techniques were used to decompose and identify the different elements constituting the source signal (mother's signal) and noise cancellation by Multivariate Empirical Mode Decomposition (MEMD) technique. The signal was adaptively decomposed by LMS, DWT and MUSIC according to optimised parameters to extract some hidden components of the source signal, such as the foetal features, QRS, heartbeat etc. The results have showed that LMS, with enhancements, is more effective in identifying and removing useless noise. The techniques were applied to the ECG signal of a 30-year-old healthy pregnant woman, which allowed to verify their applicability. The present research leads to the below main contributions among others: separation of the ECG signal of the foetus from the mother, highlighting the functional state of the foetal heart rhythm (heart rate and heartbeat,) and this can show us if the foetal ECG has malfunctions.
43
Joslyn, Nicholas J., and David R. Dowling. "Improved single snapshot beamforming in a noisy environment using the cubic autoproduct." Journal of the Acoustical Society of America 152, no. 4 (2022): A143. http://dx.doi.org/10.1121/10.0015830.
Full textAbstract:
The presence of random noise is a challenge for remote sensing tasks as success typically diminishes with decreasing signal-to-noise ratio (SNR). To improve performance in noisy environments, signal processing techniques commonly implement snapshot averaging, requiring multiple signal samples. This presentation investigates the improvement offered by the cubic autoproduct for low SNR beamforming with a single snapshot. Prior work has demonstrated the utility of a quadratic product of complex field amplitudes within the signal bandwidth for beamforming and matched field applications. This quadratic field product, known as the frequency-difference autoproduct, is a synthetic estimate of an acoustic field at the difference frequency of the two constituent fields. That formulation is extended here to a cubic product of three complex field amplitudes within the signal bandwidth, termed the cubic autoproduct, capable of mimicking field content at frequencies below, above, and within the signal bandwidth. Important features and the mathematical description of the cubic autoproduct are reviewed before discussing the beamforming approach. Single snapshot beamforming results from experimental data, acquired in a noisy underwater environment, are directly compared between the cubic frequency-difference autoproduct and the acoustic field. [Work supported by ONR and by the US DoD through an NDSEG Fellowship.]
44
Song, Xin, Jin Kuan Wang, and Bin Wang. "Efficient Robust Blind Beamforming Algorithm." Advanced Materials Research 204-210 (February 2011): 1390–93. http://dx.doi.org/10.4028/www.scientific.net/amr.204-210.1390.
Full textAbstract:
Because blind adaptive beamforming algorithms do not depend on any reference signal, they have found numerous important applications in signal processing. However, the conventional constrained constant modulus algorithm (CMA) may suffer significant performance degradation in the presence of the slight mismatches between the actual and assumed signal steering vectors. In this paper, to combat the mismatches, a novel robust constrained CMA is proposed for implementing double constraints with recursive method updating, which is based on explicit modeling of uncertainties in the desired signal array response. The proposed robust constrained CMA provides an improved robustness against the signal steering vector mismatches, enhances the array system performance under random perturbations in sensor parameters and makes the mean output array SINR consistently close to the optimal one. The performance of the proposed algorithm is compared with that of linear constrained CMA algorithm by computer simulations, the results of which demonstrate a marked improvement in the robustness against signal steering vector mismatches.
45
Xu, You Gen, and Zhi Wen Liu. "Adaptive Beamforming for Noncircular Signals." Advanced Materials Research 429 (January 2012): 318–23. http://dx.doi.org/10.4028/www.scientific.net/amr.429.318.
Full textAbstract:
Many manmade signals have nonzero noncircularity coefficients such as those used in AM, BPSK, and ASK systems. They are called noncircular signals which have coexisted moment and conjugate moment at the second-order. This redundancy is herein exploited to derive a blind scheme for source separation and classification based on the NonCircularity REstoral (NCRE4) filtering. The present blind scheme has three major advantages: 1) involves only the second-order statistics (SOS) and has a faster convergence speed than the traditional high-order statistics (HOS) methods; and 2) does not require any a prioriknowledge about the content and/or direction of the signal-of-interest (SOI).
46
Cui, Lin, Kai Xue, Boyan Wang, and Yuanbang Zhang. "Robust Adaptive Beamforming Algorithm Based on Complex Gauss–Legendre Integral." Electronics 12, no. 18 (2023): 3794. http://dx.doi.org/10.3390/electronics12183794.
Full textAbstract:
This study addresses the poor robustness of the current beamforming algorithm for covariance matrix reconstruction and the high computational complexity in the covariance matrix reconstruction process. A robust beamforming algorithm based on the Complex Gauss–Legendre integral is proposed. The method firstly partitions the neighborhood of the interference signal and constructs the interference signal space using the complex Gauss-Legendre integral, then projects the received signal into the interference signal space to filter out the desired signal and complete the reconstruction of the interference noise covariance matrix, before finally correcting the steering vector mismatch using the improved optimal steering vector estimation method. The simulation results show that the method has good robustness and a low sidelobe in the presence of the steering vector mismatch and the presence of array perturbation. Compared with the previous works, the proposed CGL-ISV method provides a better beamforming performance.
47
Yang, Jin, Xiaodong Chen, Huaiyu Cai, and Yi Wang. "Generalized sidelobe canceler beamforming combined with Eigenspace-Wiener postfilter for medical ultrasound imaging." Technology and Health Care 30 (February 25, 2022): 501–12. http://dx.doi.org/10.3233/thc-thc228046.
Full textAbstract:
BACKGROUND: The beamforming algorithm is key to the image quality of the medical ultrasound system. The generalized sidelobe canceler (GSC) beamforming can improve the image quality in lateral resolution, but the contrast is not improved correspondingly. OBJECTIVE: In our research, we try to optimize the generalized sidelobe canceler to obtain images that achieve an improvement in both lateral resolution and contrast. METHODS: We put forward a new beamforming algorithm which combines the generalized sidelobe canceler and Eigenspace-Wiener postfilter. According to eigenspace decomposition of the covariance matrix of the received data, the components of the Wiener postfilter can be calculated from the signal matrix and the noise matrix. Then, the adaptive weight vector of GSC is further constrained by the Eigenspace-Wiener postfilter, which make the output energy of the receiving array closer to the desired signal than the conventional GSC output. RESULTS: We compare the new beamforming algorithm with delay-and-sum (DS) beamforming, synthetic aperture (SA) beamforming, and GSC beamforming using the simulated and experimental data sets. The quantitative results show that our method reduces the FWHM by 85.5%, 80.5%, and 38.9% while improving the CR by 123.6%, 47.7%, 84.4% on basis of DS, SA, and GSC beamforming, respectively. CONCLUSIONS: The new beamforming algorithm can obviously improve the imaging quality of medical ultrasound imaging systems in both lateral resolution and contrast.
48
Wagner, Gregory S., and Thomas J. Owens. "Signal detection using multi-channel seismic data." Bulletin of the Seismological Society of America 86, no. 1A (1996): 221–31. http://dx.doi.org/10.1785/bssa08601a0221.
Full textAbstract:
Abstract We outline a simple signal detection approach for multi-channel seismic data. Our approach is based on the premise that the wave-field spatial coherence increases when a signal is present. A measure of spatial coherence is provided by the largest eigenvalue of the multi-channel data's sample covariance matrix. The primary advantages of this approach are its speed and simplicity. For three-component data, this approach provides a more robust statistic than particle motion polarization. For array data, this approach provides beamforming-like signal detection results without the need to form beams. This approach allows several options for the use of three-component array data. Detection statistics for three-component, vertical-component array, and three different three-component array approaches are compared to conventional and minimum-variance vertical-component beamforming. Problems inherent in principal-component analysis (PCA) in general and PCA of high-frequency seismic data in particular are also discussed. Multi-channel beamforming and the differences between principal component and factor analysis are discussed in the appendix.
49
Darzi, Soodabeh, Tiong Sieh Kiong, Mohammad Tariqul Islam, Mahamod Ismail, Salehin Kibria, and Balasem Salem. "Null Steering of Adaptive Beamforming Using Linear Constraint Minimum Variance Assisted by Particle Swarm Optimization, Dynamic Mutated Artificial Immune System, and Gravitational Search Algorithm." Scientific World Journal 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/724639.
Full textAbstract:
Linear constraint minimum variance (LCMV) is one of the adaptive beamforming techniques that is commonly applied to cancel interfering signals and steer or produce a strong beam to the desired signal through its computed weight vectors. However, weights computed by LCMV usually are not able to form the radiation beam towards the target user precisely and not good enough to reduce the interference by placing null at the interference sources. It is difficult to improve and optimize the LCMV beamforming technique through conventional empirical approach. To provide a solution to this problem, artificial intelligence (AI) technique is explored in order to enhance the LCMV beamforming ability. In this paper, particle swarm optimization (PSO), dynamic mutated artificial immune system (DM-AIS), and gravitational search algorithm (GSA) are incorporated into the existing LCMV technique in order to improve the weights of LCMV. The simulation result demonstrates that received signal to interference and noise ratio (SINR) of target user can be significantly improved by the integration of PSO, DM-AIS, and GSA in LCMV through the suppression of interference in undesired direction. Furthermore, the proposed GSA can be applied as a more effective technique in LCMV beamforming optimization as compared to the PSO technique. The algorithms were implemented using Matlab program.
50
Kim, Hyungwoo, Jinwoo Kim, Jinha Kim, et al. "Calibration of Wideband LFM Radars Based on Sliding Window Algorithm." Electronics 12, no. 17 (2023): 3564. http://dx.doi.org/10.3390/electronics12173564.
Full textAbstract:
This paper addresses the challenges of wideband signal beamforming in radar systems and proposes a new calibration method. Due to operating conditions, the frequency-dependent characteristics of the system can be changed, and the amplitude, phase, and time delay error can be generated. The proposed method is based on the concept of the sliding window algorithm for linear frequency modulated (LFM) signals. To calibrate the frequency-dependent errors from the transceiver and the time delay error from the true time delay elements, the proposed method utilizes the characteristic of the LFM signal. The LFM signal changes its frequency linearly with time, and the frequency domain characteristics of the hardware are presented in time. Therefore, by applying a matched filter to a part of the LFM signal, the frequency-dependent characteristics can be monitored and calibrated. The proposed method is compared with the conventional matched filter-based calibration results and verified by simulation results and beampatterns. Since the proposed method utilizes LFM signal as the calibration tone, the proposed method can be applied to any beamforming systems, not limited to LFM radars.