{"title":"Optimum Waveform Selection for Target State Estimation in the Joint Radar-Communication System","authors":"Ashoka Chakravarthi Mahipathi;Bethi Pardha Pardhasaradhi;Srinath Gunnery;Pathipati Srihari;John d'Souza;Paramananda Jena","doi":"10.1109/OJSP.2024.3359997","DOIUrl":"https://doi.org/10.1109/OJSP.2024.3359997","url":null,"abstract":"The widespread usage of the Radio Frequency (RF) spectrum for wireless and mobile communication systems generated a significant spectrum scarcity. The Joint Radar-Communication System (JRCS) provides a framework to simultaneously utilize the allocated radar spectrum for sensing and communication purposes. Generally, a Successive Interference Cancellation (SIC) based receiver is applied to mitigate mutual interference in the JRCS configuration. However, this SIC receiver model introduces a communication residual component. In response to this issue, the article presents a novel measurement model based on communication residual components for various radar waveforms. The radar system's performance within the JRCS framework is then evaluated using the Fisher Information Matrix (FIM). The radar waveforms considered in this investigation are rectangular pulse, triangular pulse, Gaussian pulse, Linear Frequency Modulated (LFM) pulse, LFM-Gaussian pulse, and Non-Linear Frequency Modulated (NLFM) pulse. After that, the Kalman filter is deployed to estimate the target kinematics (range and range rate) of a single linearly moving target for different waveforms. Additionally, range and range rate estimation errors are quantified using the Root Mean Square Error (RMSE) metric. Furthermore, the Posterior Cramer-Rao Lower Bound (PCRLB) is derived to validate the estimation accuracy of various waveforms. The simulation results show that the range and range rate estimation errors are within the PCRLB limit at all time instants for all the designated waveforms. The results further reveal that the NLFM pulse waveform provides improved range and range rate error performance compared to all other waveforms.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"459-477"},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10416352","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139987097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Robust and Simple ADMM Penalty Parameter Selection","authors":"MICHAEL T. MCCANN;Brendt Wohlberg","doi":"10.1109/OJSP.2023.3349115","DOIUrl":"https://doi.org/10.1109/OJSP.2023.3349115","url":null,"abstract":"We present a new method for online selection of the penalty parameter for the alternating direction method of multipliers (ADMM) algorithm. ADMM is a widely used method for solving a range of optimization problems, including those that arise in signal and image processing. In its standard form, ADMM includes a scalar hyperparameter, known as the penalty parameter, which usually has to be tuned to achieve satisfactory empirical convergence. In this work, we develop a framework for analyzing the ADMM algorithm applied to a quadratic problem as an affine fixed point iteration. Using this framework, we develop a new method for automatically tuning the penalty parameter by detecting when it has become too large or small. We analyze this and several other methods with respect to their theoretical properties, i.e., robustness to problem transformations, and empirical performance on several optimization problems. Our proposed algorithm is based on a theoretical framework with clear, explicit assumptions and approximations, is theoretically covariant/invariant to problem transformations, is simple to implement, and exhibits competitive empirical performance.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"402-420"},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10387940","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139749914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dagma-DCE: Interpretable, Non-Parametric Differentiable Causal Discovery","authors":"Daniel Waxman;Kurt Butler;Petar M. Djurić","doi":"10.1109/OJSP.2024.3351593","DOIUrl":"10.1109/OJSP.2024.3351593","url":null,"abstract":"We introduce \u0000<sc>Dagma-DCE</small>\u0000, an interpretable and model-agnostic scheme for differentiable causal discovery. Current non- or over-parametric methods in differentiable causal discovery use opaque proxies of “independence” to justify the inclusion or exclusion of a causal relationship. We show theoretically and empirically that these proxies may be arbitrarily different than the actual causal strength. Juxtaposed with existing differentiable causal discovery algorithms, \u0000<sc>Dagma-DCE</small>\u0000 uses an interpretable measure of causal strength to define weighted adjacency matrices. In a number of simulated datasets, we show our method achieves state-of-the-art level performance. We additionally show that \u0000<sc>Dagma-DCE</small>\u0000 allows for principled thresholding and sparsity penalties by domain-experts. The code for our method is available open-source at \u0000<uri>https://github.com/DanWaxman/DAGMA-DCE</uri>\u0000, and can easily be adapted to arbitrary differentiable models.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"393-401"},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10384714","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139450118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Face Reflection Removal Network Using Multispectral Fusion of RGB and NIR Images","authors":"Hui Lan;Enquan Zhang;Cheolkon Jung","doi":"10.1109/OJSP.2024.3351472","DOIUrl":"https://doi.org/10.1109/OJSP.2024.3351472","url":null,"abstract":"Images captured through glass are usually contaminated by reflections, and the removal of them from images is a challenging task. Since the primary concern on photos is face, the face images with reflections annoy viewers severely. In this article, we propose a face reflection removal network using multispectral fusion of color (RGB) and near infrared (NIR) images, called FRRN. Due to the different spectral wavelengths of visible light [380 nm, 780 nm] and near infrared [780 nm, 2526 nm], NIR cameras are not sensitive to the visible light and thus NIR images are less corrupted by reflections. NIR images preserve structure information well and can guide the restoration process from reflections on the RGB images. Thus, we adopt multispectual fusion of RGB and NIR images for reflection removal from a face image. FRRN consists of one encoder model (contextual encoder model (CEM)) and two decoder models (NIR inference decoder model (NIDM) and image inference decoder model (IIDM)). CEM captures features from shallow to deep layers on the scene information while suppressing the sparse reflection component. NIDM infers NIR image to facilitate multi-scale guidance for reflection removal, while IIDM estimates the transmission layer with the guidance of NIDM. Besides, we present the reflection confidence generation module (RCGM) based on Laplacian convolution and channel attention-based residual block (CARB) to represent the reflection confidence in a region for reflection removal. To train FRRN, we construct a large-scale training dataset with face image and reflection layer (RGB and NIR images) and its corresponding test dataset using JAI AD-130 GE camera. Various experiments demonstrate that FRRN outperforms state-of-the-art methods for reflection removal in terms of visual quality and quantitative measurements.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"383-392"},"PeriodicalIF":0.0,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10384724","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139676115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shayan Gharib;Minh Tran;Diep Luong;Konstantinos Drossos;Tuomas Virtanen
{"title":"Adversarial Representation Learning for Robust Privacy Preservation in Audio","authors":"Shayan Gharib;Minh Tran;Diep Luong;Konstantinos Drossos;Tuomas Virtanen","doi":"10.1109/OJSP.2023.3349113","DOIUrl":"https://doi.org/10.1109/OJSP.2023.3349113","url":null,"abstract":"Sound event detection systems are widely used in various applications such as surveillance and environmental monitoring where data is automatically collected, processed, and sent to a cloud for sound recognition. However, this process may inadvertently reveal sensitive information about users or their surroundings, hence raising privacy concerns. In this study, we propose a novel adversarial training method for learning representations of audio recordings that effectively prevents the detection of speech activity from the latent features of the recordings. The proposed method trains a model to generate invariant latent representations of speech-containing audio recordings that cannot be distinguished from non-speech recordings by a speech classifier. The novelty of our work is in the optimization algorithm, where the speech classifier's weights are regularly replaced with the weights of classifiers trained in a supervised manner. This increases the discrimination power of the speech classifier constantly during the adversarial training, motivating the model to generate latent representations in which speech is not distinguishable, even using new speech classifiers trained outside the adversarial training loop. The proposed method is evaluated against a baseline approach with no privacy measures and a prior adversarial training method, demonstrating a significant reduction in privacy violations compared to the baseline approach. Additionally, we show that the prior adversarial method is practically ineffective for this purpose.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"294-302"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10379095","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139488162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Signal Processing in the Retina: Interpretable Graph Classifier to Predict Ganglion Cell Responses","authors":"Yasaman Parhizkar;Gene Cheung;Andrew W. Eckford","doi":"10.1109/OJSP.2023.3349111","DOIUrl":"10.1109/OJSP.2023.3349111","url":null,"abstract":"It is a popular hypothesis in neuroscience that ganglion cells in the retina are activated by selectively detecting visual features in an observed scene. While ganglion cell firings can be predicted via data-trained deep neural nets, the networks remain indecipherable, thus providing little understanding of the cells' underlying operations. To extract knowledge from the cell firings, in this paper we learn an interpretable graph-based classifier from data to predict the firings of ganglion cells in response to visual stimuli. Specifically, we learn a positive semi-definite (PSD) metric matrix \u0000<inline-formula><tex-math>${mathbf {M}}succeq 0$</tex-math></inline-formula>\u0000 that defines Mahalanobis distances between graph nodes (visual events) endowed with pre-computed feature vectors; the computed inter-node distances lead to edge weights and a combinatorial graph that is amenable to binary classification. Mathematically, we define the objective of metric matrix \u0000<inline-formula><tex-math>${mathbf {M}}$</tex-math></inline-formula>\u0000 optimization using a graph adaptation of large margin nearest neighbor (LMNN), which is rewritten as a semi-definite programming (SDP) problem. We solve it efficiently via a fast approximation called Gershgorin disc perfect alignment (GDPA) linearization. The learned metric matrix \u0000<inline-formula><tex-math>${mathbf {M}}$</tex-math></inline-formula>\u0000 provides interpretability: important features are identified along \u0000<inline-formula><tex-math>${mathbf {M}}$</tex-math></inline-formula>\u0000’s diagonal, and their mutual relationships are inferred from off-diagonal terms. Our fast metric learning framework can be applied to other biological systems with pre-chosen features that require interpretation.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"303-311"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10379097","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139388541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alexander Karataev;Christian Forsch;Laura Cottatellucci
{"title":"Bilinear Expectation Propagation for Distributed Semi-Blind Joint Channel Estimation and Data Detection in Cell-Free Massive MIMO","authors":"Alexander Karataev;Christian Forsch;Laura Cottatellucci","doi":"10.1109/OJSP.2023.3348343","DOIUrl":"10.1109/OJSP.2023.3348343","url":null,"abstract":"We consider a cell-free massive multiple-input multiple-output (CF-MaMIMO) communication system in the uplink transmission and propose a novel algorithm for blind or semi-blind joint channel estimation and data detection (JCD). We formulate the problem in the framework of bilinear inference and develop a solution based on the expectation propagation (EP) method for both channel estimation and data detection. We propose a new approximation of the joint a posteriori distribution of the channel and data whose representation as a factor graph enables the application of the EP approach using the message-passing technique, local low-complexity computations at the nodes, and an effective modeling of channel-data interplay. The derived algorithm, called bilinear-EP JCD, allows for a distributed implementation among access points (APs) and the central processing unit (CPU) and has polynomial complexity. Our simulation results show that it outperforms other EP-based state-of-the-art polynomial time algorithms.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"284-293"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10378663","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139175602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Detection and Estimation of Gas Sources With Arbitrary Locations Based on Poisson's Equation","authors":"Dmitriy Shutin;Thomas Wiedemann;Patrick Hinsen","doi":"10.1109/OJSP.2023.3344076","DOIUrl":"https://doi.org/10.1109/OJSP.2023.3344076","url":null,"abstract":"Accurate estimation of the number and locations of dispersed material sources is critical for optimal disaster response in Chemical, Biological, Radiological, or Nuclear accidents. This paper introduces a novel approach to Gas Source Localization that uses sparse Bayesian learning adapted to models based on Partial Differential Equations for modeling gas dynamics. Using the method of Green's functions and the adjoint state method, a gradient-based optimization with respect to source locations is derived, allowing superresolving (arbitrary) source locations. By combing the latter with sparse Bayesian learning, a sparse source support can be identified, thus indirectly assessing the number of sources. Simulation results and comparisons with classical sparse estimators for linear models demonstrate the effectiveness of the proposed approach. The proposed sparsity-constrained gas source localization method offers thus a flexible solution for disaster response and robotic exploration in hazardous environments.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"359-373"},"PeriodicalIF":0.0,"publicationDate":"2023-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10368587","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139573275","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emilie d'Olne;Alastair H. Moore;Patrick A. Naylor;Jacob Donley;Vladimir Tourbabin;Thomas Lunner
{"title":"Group Conversations in Noisy Environments (GiN) – Multimedia Recordings for Location-Aware Speech Enhancement","authors":"Emilie d'Olne;Alastair H. Moore;Patrick A. Naylor;Jacob Donley;Vladimir Tourbabin;Thomas Lunner","doi":"10.1109/OJSP.2023.3344379","DOIUrl":"https://doi.org/10.1109/OJSP.2023.3344379","url":null,"abstract":"Recent years have seen a growing interest in the use of smart glasses mounted with microphones to solve the cocktail party problem using beamforming techniques or machine learning. Many such approaches could bring substantial advances in hearing aid or Augmented Reality (AR) research. To validate these methods, the EasyCom [Donley et al., 2021] dataset introduced high-quality multi-modal recordings of conversations in noise, including egocentric multi-channel microphone array audio, speech source pose, and headset microphone audio. While providing comprehensive data, EasyCom lacks diversity in the acoustic environments considered and the degree of overlapping speech in conversations. This work therefore presents the Group in Noise (GiN) dataset of over 2 hours of group conversations in noisy environments recorded using binaural microphones and a pair of glasses mounted with 5 microphones. The recordings took place in 3 rooms and contain 6 seated participants as well as a standing facilitator. The data also include close-talking microphone audio and head-pose data for each speaker, an audio channel from a fixed reference microphone, and automatically annotated speaker activity information. A baseline method is used to demonstrate the use of the data for speech enhancement. The dataset is publicly available in d'Olne et al. [2023].","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"374-382"},"PeriodicalIF":0.0,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10365406","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139573273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Denis C. Ilie-Ablachim;Andra Băltoiu;Bogdan Dumitrescu
{"title":"Sparse Representation With Gaussian Atoms and Its Use in Anomaly Detection","authors":"Denis C. Ilie-Ablachim;Andra Băltoiu;Bogdan Dumitrescu","doi":"10.1109/OJSP.2023.3344313","DOIUrl":"https://doi.org/10.1109/OJSP.2023.3344313","url":null,"abstract":"We propose sparse representation and dictionary learning algorithms for dictionaries whose atoms are characterized by Gaussian probability distributions around some central atoms. This extension of the space covered by the atoms permits a better characterization of localized features of the signals. The representations are computed by trading-off representation error and the probability of the actual atoms used in the representation. We propose two types of algorithms: a greedy one, similar in spirit with Orthogonal Matching Pursuit, and one based on L1-regularization. We apply our new algorithms to unsupervised anomaly detection, where the representation error is used as anomaly score. The flexibility of our approach appears to improve more the representations of the many normal signals than those of the few outliers, at least for an anomaly type called dependency, thus improving the detection quality. Comparison with both standard dictionary learning algorithms and established anomaly detection methods is favorable.","PeriodicalId":73300,"journal":{"name":"IEEE open journal of signal processing","volume":"5 ","pages":"168-176"},"PeriodicalIF":0.0,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10365333","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139060324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}