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Wideband multitarget passive tracking based on belief propagation theory
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-30 DOI: 10.1016/j.sigpro.2024.109813
Shuo Li, Nan Zou, Jinjin Wang, Guolong Liang, Xiang Li, Ying Lyu
{"title":"Wideband multitarget passive tracking based on belief propagation theory","authors":"Shuo Li,&nbsp;Nan Zou,&nbsp;Jinjin Wang,&nbsp;Guolong Liang,&nbsp;Xiang Li,&nbsp;Ying Lyu","doi":"10.1016/j.sigpro.2024.109813","DOIUrl":"10.1016/j.sigpro.2024.109813","url":null,"abstract":"<div><div>In passive acoustic monitoring system, information is typically derived from radiated noise signals of targets distributed across multiple subbands. When targets are close in the node field of view, direct processing of the entire frequency band may lead to premature merging of detection results or masking of weaker targets due to differences in energy distribution among the target bands. This situation can degrade the performance of tracking algorithms because the downstream tracking processing cannot compensate for the loss of upstream measurements. This study proposes a novel wideband multitarget tracking algorithm based on belief propagation to address this challenge. Initially, a merged target model is established to simulate the mechanism of measurement generation from multiple targets. Based on this model, merged targets and each subband measurement form a cyclic association structure. This structure is processed using the loopy belief propagation algorithm to prevent the combinatorial explosion. A mixture of belief and mutual information entropy weight is established for each subband to fuse all posterior probability density functions, considering differences in subband energy distribution. Simulation and lake trial results demonstrate that this algorithm substantially improves the tracking capabilities of passive acoustic monitoring system for wideband targets, underscoring its practical application value.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109813"},"PeriodicalIF":3.4,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Superdirective beamforming based on spherical harmonic expansion on planar acoustic vector sensor arrays
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-29 DOI: 10.1016/j.sigpro.2024.109836
Mingqian Han , Junyuan Guo
{"title":"Superdirective beamforming based on spherical harmonic expansion on planar acoustic vector sensor arrays","authors":"Mingqian Han ,&nbsp;Junyuan Guo","doi":"10.1016/j.sigpro.2024.109836","DOIUrl":"10.1016/j.sigpro.2024.109836","url":null,"abstract":"<div><div>The superdirective beamforming method based on spherical harmonic expansion is capable of generating a frequency-invariant three-dimensional (3D) beampattern. When applied to planar acoustic vector sensor arrays (PAVSAs), this method may yield a distorted beampattern. To rectify the issue of inaccurate beampattern steering, the main lobe constraints are introduced to align the main lobe's steering direction with the intended direction. An optimized superdirective beamforming method is proposed by integrating the superdirective beamformer based on spherical harmonic expansion with the main lobe constraints. Then, a robust version of the proposed beamformer is also proposed by employing the white noise gain (WNG) constraint. The simulation results corroborate the theoretical analysis and substantiate the feasibility and superiority of the proposed methods.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109836"},"PeriodicalIF":3.4,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A tensor model for the calibration of air-coupled ultrasonic sensor arrays in 3D imaging
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-28 DOI: 10.1016/j.sigpro.2024.109812
Raphael Müller , Gianni Allevato , Matthias Rutsch , Christoph Haugwitz, Tianyi Liu (刘添翼), Mario Kupnik, Marius Pesavento
{"title":"A tensor model for the calibration of air-coupled ultrasonic sensor arrays in 3D imaging","authors":"Raphael Müller ,&nbsp;Gianni Allevato ,&nbsp;Matthias Rutsch ,&nbsp;Christoph Haugwitz,&nbsp;Tianyi Liu (刘添翼),&nbsp;Mario Kupnik,&nbsp;Marius Pesavento","doi":"10.1016/j.sigpro.2024.109812","DOIUrl":"10.1016/j.sigpro.2024.109812","url":null,"abstract":"<div><div>Arrays of ultrasonic sensors are capable of 3D imaging in air and an affordable supplement to other sensing modalities, such as radar, lidar, and camera, i.e.in heterogeneous sensing systems. However, manufacturing tolerances of air-coupled ultrasonic sensors may lead to amplitude and phase deviations. Together with artifacts from imperfect knowledge of the array geometry, there are numerous factors that can impair the imaging performance of an array. We propose a reference-based calibration method to overcome possible limitations. First, we introduce a novel tensor signal model to capture the characteristics of piezoelectric ultrasonic transducers (PUTs) and the underlying multidimensional nature of a multiple-input multiple-output (MIMO) sensor array. Second, we formulate and solve an optimization problem based on this model to obtain the calibrated parameters of the array. Third, we assess both our model and the commonly used analytic model using real data from a 3D imaging experiment. The experiment reveals that our array response model we learned with calibration data yields an imaging performance similar to that of the analytic array model, which requires perfect array geometry information.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109812"},"PeriodicalIF":3.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143132057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A saddlepoint approximation for the smoothed periodogram 平滑周期图的鞍点近似
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-28 DOI: 10.1016/j.sigpro.2024.109758
Dakota Roberson , S. Huzurbazar
{"title":"A saddlepoint approximation for the smoothed periodogram","authors":"Dakota Roberson ,&nbsp;S. Huzurbazar","doi":"10.1016/j.sigpro.2024.109758","DOIUrl":"10.1016/j.sigpro.2024.109758","url":null,"abstract":"<div><div>Poor variance properties of the periodogram often limit its practical applicability to a wide range of modern spectral estimation and detection applications. The smoothed periodogram, a refined periodogram-based method, is one such nonparametric approach to reducing variance. Neighboring spectral samples are averaged across a spectral window, as opposed to the more common temporal or lag window. Tapered spectral windows and other modifications needed to address the time-bandwidth product and resolution-variance trade-offs complicate the statistical analysis, making it difficult to quantify statistical performance. In addition, approximate distributions for the smoothed periodogram require <em>a priori</em> normalization along with simplifying assumptions to yield computationally tractable results. Here, under mild asymptotic conditions, the distribution derived prior to normalization is shown to be computationally intractable in most cases. First-order statistical approximations are computationally stable but result in sizeable inaccuracies, particularly in the tails. We use a saddlepoint approximation, a second-order asymptotic method, that allows for accurate statistical characterization but is also numerically stable. Monte Carlo simulations are used to validate the results and to illustrate the robustness of the approach. Finally, its utility is demonstrated on a real-world dataset relevant to the side-channel and hardware cybersecurity communities.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109758"},"PeriodicalIF":3.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142756676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Multifunctional adversarial examples: A novel mechanism for authenticatable privacy protection of images 多功能对抗示例:一种用于图像可验证隐私保护的新机制
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-28 DOI: 10.1016/j.sigpro.2024.109816
Ming Li , Si Wang
{"title":"Multifunctional adversarial examples: A novel mechanism for authenticatable privacy protection of images","authors":"Ming Li ,&nbsp;Si Wang","doi":"10.1016/j.sigpro.2024.109816","DOIUrl":"10.1016/j.sigpro.2024.109816","url":null,"abstract":"<div><div>With the rapid development of network technology, more and more images containing personal identity characteristics are being released by users on open network platforms. However, these images are easily collected by malicious users, leading to problems such as privacy leakage, infringement, and tampering, thus harming users’ legitimate interests. Recent studies have found that adversarial examples generated by adding tiny perturbations to an image can mislead image classifiers, causing incorrect classifications. Therefore significant privacy protection against deep neural networks is achieved while the visual quality remains indistinguishable to human eyes. However, these methods cannot protect the authenticity and integrity of the image simultaneously, failing to address infringement and tampering issues, which are also neglectable in the open network platforms. To solve this problem, we propose a novel authentication-enabled privacy protection method. The meaningful information used for authentication, instead of the meaningless perturbations, is embedded into the host image to generate adversarial examples, thereby achieving both authentication and privacy protection simultaneously. This scheme combines attention mechanisms with generative adversarial networks to adaptively select and weight features between different channels, achieving significant improvements in both aggressiveness and authentication capability. Experimental results show that our method outperforms recent similar methods in overall performance.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109816"},"PeriodicalIF":3.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Progressive Gaussian filtering for nonlinear uncertain systems based on Gaussian process models 基于高斯过程模型的非线性不确定系统的渐进高斯滤波
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-26 DOI: 10.1016/j.sigpro.2024.109801
Qichao Wang , Xiaolei Zhuge , Xusheng Yang , Wen-An Zhang
{"title":"Progressive Gaussian filtering for nonlinear uncertain systems based on Gaussian process models","authors":"Qichao Wang ,&nbsp;Xiaolei Zhuge ,&nbsp;Xusheng Yang ,&nbsp;Wen-An Zhang","doi":"10.1016/j.sigpro.2024.109801","DOIUrl":"10.1016/j.sigpro.2024.109801","url":null,"abstract":"<div><div>This paper studies the problem of progressive Gaussian filtering (PGF) for nonlinear uncertain systems, and a PGF method is proposed by incorporating Gaussian process (GP) models to improve the compensation ability for measurement uncertainties. Firstly, the measurements are classified by the Chi-square test, and an adaptive strategy for controlling the pseudo-duration of progressive measurement update is designed to compensate for measurement uncertainties. Moreover, a conservative upper bound of the pseudo-duration is given to obtain conservative estimates. Secondly, to mitigate the adverse effects caused by measurement uncertainties on state predictions, the GP model is incorporated into the PGF. Finally, the effectiveness and superiority of the proposed method are validated through simulation results.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109801"},"PeriodicalIF":3.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A broken-track association method for robust multi-target tracking adopting multi-view Doppler measurement information 一种采用多视角多普勒测量信息的破航迹关联鲁棒多目标跟踪方法
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-26 DOI: 10.1016/j.sigpro.2024.109815
Jiaqi Zhang , Cao Zeng , Haihong Tao , Yuhong Zhang , Shihua Zhao , Qirui Wu
{"title":"A broken-track association method for robust multi-target tracking adopting multi-view Doppler measurement information","authors":"Jiaqi Zhang ,&nbsp;Cao Zeng ,&nbsp;Haihong Tao ,&nbsp;Yuhong Zhang ,&nbsp;Shihua Zhao ,&nbsp;Qirui Wu","doi":"10.1016/j.sigpro.2024.109815","DOIUrl":"10.1016/j.sigpro.2024.109815","url":null,"abstract":"<div><div>Due to reasons such as target maneuvering and track crossing, mistaken track association may be caused. When the target is in Doppler blind zone, it often leads to the loss of measurement information, which is reflected in the situation as track breakage. In response to the demand of track repair in the case of track breakage, we propose a robust multi-target broken-track association method that comprehensively utilizes multi-view Doppler measurement information. Firstly, based on the derivation of measurement coordinate transformation bias, the multi-sensor Doppler measurement after error correction is fused to obtain the heading velocity and heading acceleration measurement of the target. Secondly, the multi-scan association cost function based on the heading velocity and heading acceleration measurement is constructed, and the optimal correlation sequence is obtained by minimizing the complexity of the cost function. Then, for the case of missing measurements, the optimal association sequence is used to extrapolate the missing measurements, thereby accomplishing the correlation among the broken track segment, the extrapolated measurement and the optimal correlation sequence. Thirdly, we design a multi-scan GLMB smoother to perform forward prediction and backward smoothing on the above correlation results to improve the smoothness of the track. Simulation and actual experimental results suggest that our proposed method can effectively deal with the track breakage situation of dense targets, particularly in track integrity, track accuracy and robustness compared with the existing approaches.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109815"},"PeriodicalIF":3.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A privacy-preserving license plate encryption scheme based on an improved YOLOv8 image recognition algorithm 一种基于改进的YOLOv8图像识别算法的车牌保密加密方案
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-26 DOI: 10.1016/j.sigpro.2024.109811
Chengye Zou , Yunong Liu , Yongwei Yang , Changjun Zhou , Yang Yu , Yubao Shang
{"title":"A privacy-preserving license plate encryption scheme based on an improved YOLOv8 image recognition algorithm","authors":"Chengye Zou ,&nbsp;Yunong Liu ,&nbsp;Yongwei Yang ,&nbsp;Changjun Zhou ,&nbsp;Yang Yu ,&nbsp;Yubao Shang","doi":"10.1016/j.sigpro.2024.109811","DOIUrl":"10.1016/j.sigpro.2024.109811","url":null,"abstract":"<div><div>With the rapid development of green smart cities, urban intelligence has also brought new challenges, particularly in protecting the privacy information of vehicles within the city. To address this issue, we propose a novel image encryption scheme to ensure the security of image transmission. This method captures vehicle images through roadside surveillance cameras and uses an improved YOLOv8 algorithm to identify sensitive vehicle information in real time, which is then securely transmitted to the city’s traffic management system. To safeguard the data, we employ a combination of the Rabbit Competition scrambling algorithm and a custom diffusion kernel to perform real-time encryption on the identified image regions, protecting privacy-sensitive areas. Experimental results show that our method improves accuracy by 1.53% and average precision by 1.4% on the test set compared to the baseline model, indicating a substantial enhancement in detection accuracy. Additionally, the encryption scheme demonstrates a larger key space, improved robustness, and significantly enhanced anti-attack capabilities, confirming its effectiveness in protecting vehicle information in smart city environments.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109811"},"PeriodicalIF":3.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142744663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Simplified ICF and smart MIR for PAPR reduction in OFDM systems OFDM系统中减少PAPR的简化ICF和智能MIR
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-26 DOI: 10.1016/j.sigpro.2024.109804
Heng Du, Jiang Xue , Weilin Song, Qihong Duan
{"title":"Simplified ICF and smart MIR for PAPR reduction in OFDM systems","authors":"Heng Du,&nbsp;Jiang Xue ,&nbsp;Weilin Song,&nbsp;Qihong Duan","doi":"10.1016/j.sigpro.2024.109804","DOIUrl":"10.1016/j.sigpro.2024.109804","url":null,"abstract":"<div><div>One of the biggest problems for orthogonal frequency division multiplexing (OFDM) systems is the high peak-to-average power ratio (PAPR), which breaks the orthogonality among subcarriers and leads to the nonlinear distortion of transmitted signals after being processed by the power amplifier (PA). The iterative clipping and filtering (ICF) method is one of the well known and applied existing PAPR reduction techniques at the transmitter and the modified iterative receiver (MIR) is an effective existing method for signal recovery with the ICF method in its iterative process at the receiver. However, the ICF method, as well as the MIR, suffers from the high computational complexity due to the oversampling and high-order inverse fast Fourier transform/fast Fourier transform (IFFT/FFT) operators. Besides, the performance of MIR is limited by the number of iterations. In this paper, to reduce the computational complexity of ICF method, the phase rotation iterative clipping and filtering (PRICF) method is proposed, which performs padding, phase rotation and low-order IFFT/FFT operators. Meanwhile, the computational complexity of MIR is also reduced because the ICF method is replaced by the PRICF method in its iterative process. Furthermore, to accelerate the iteration or improve the performance, the modified iterative network receiver (MIR-Net) is proposed by introducing trainable parameters based on the method of model-driven deep learning. Comparing with the combination of ICF and MIR, the simulation results demonstrate the advantages of our proposed methods, which is the combination of PRICF and MIR-Net, in terms of the computational complexity and performance.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109804"},"PeriodicalIF":3.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
A dual-based first-order algorithm for ToA asynchronous localization and synchronization 一种基于双阶的ToA异步定位与同步算法
IF 3.4 2区 工程技术
Signal Processing Pub Date : 2024-11-26 DOI: 10.1016/j.sigpro.2024.109814
Eyal Gur , Alon Amar , Shoham Sabach
{"title":"A dual-based first-order algorithm for ToA asynchronous localization and synchronization","authors":"Eyal Gur ,&nbsp;Alon Amar ,&nbsp;Shoham Sabach","doi":"10.1016/j.sigpro.2024.109814","DOIUrl":"10.1016/j.sigpro.2024.109814","url":null,"abstract":"<div><div>Joint ToA source localization and synchronization determines the location and time offset of a radiating source using time-of-arrival measurements collected from a time-synchronized array of sensors. Various approaches have been proposed to address this non-convex and non-smooth optimization problem, which usually transform the problem by applying convex relaxations or smooth approximations. In this paper, we focus on the original joint problem and show that it can be expressed as a sum of a quadratic function with multiple non-smooth functions. This type of problems cannot be solved using traditional proximal-based methods, and we develop a tailored dual-based first-order algorithm. We analyze the proposed method, and prove its convergence to critical points of the original problem under mild assumptions. Experimental results showcase advantages of the method in terms of convergence, RMSE, bias, and complexity.</div></div>","PeriodicalId":49523,"journal":{"name":"Signal Processing","volume":"230 ","pages":"Article 109814"},"PeriodicalIF":3.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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