Advanced Electronics and Digital Signal Processing

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Electrical, Electronics and Communications Engineering".

Deadline for manuscript submissions: closed (31 December 2023) | Viewed by 11101

Special Issue Editors

Department of Electrical Engineering, National Chin-Yi University of Technology, Taiping District, Taichung City 41170, Taiwan
Interests: biomedical electronics and signal processing; artificial intelligence and its application; embedded system application; pattern recognition; demand response; power quality
Department of Electrical Engineering, National Chin-Yi University of Technology, Taiping District, Taichung City 41170, Taiwan
Interests: automatic control; microprocessor; interface control; single-chip control; logic design
Special Issues, Collections and Topics in MDPI journals
Department of Maritime Information and Technology, National Kaohsiung University of Science and Technology, Kaohsiung City 824005, Taiwan
Interests: fuzzy control; intelligent control; biomedical electronics and signal processing; artificial intelligence and its application
Department of Marine Engineering, National Kaohsiung University of Science and Technology, Kaohsiung 811, Taiwan
Interests: fuzzy control theory; neural networks; robust control; time-delay systems
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

In recent years, digital processing techniques have played a noteworthy role in the development of digital health, information systems, and smart management systems, such as telecommunication, radar and sensor-based systems, video and speech processing, digital signal/image processing, infosecurity, etc. Many advanced mathematical algorithms have been proposed to deal with potential applications in Special Issue topics with a functional analysis, stochastic calculus, fractional-order calculus, and the chaos theory. In addition, with discrete or digital data, machine learning and deep learning-based methods, such as the fuzzy-based neural network, radial basis function network, support vector machine network, and multilayer convolutional connected network, can be used for automatic signal/pattern analysis and recognition. scopes included in the industrial, biomedical, mechanical, manufacturing, and infosecurity engineering fields include techniques for visual inspection, visual search, medical image analysis/classification, video and image analysis, handwriting analysis, face and gesture recognition, and other relevant hardware and/or software.

To reach the above-mentioned aim, the proposed Special Issue requires advanced/novel mathematical and intelligent model developments in medical imaging and signal processing, smart management systems, technologies in mathematics, technology management, and infosecurity communication techniques. Through these up-to-date studies/techniques, we hope to place special emphasis on sharing emerging topics.

Special Collection from IS3C 2023: This Special Issue also pertains to the 6th International Symposium on Computer, Consumer and Control (IS3C 2023) to be held in the National Chin-Yi University of Technology, Taichung City, Taiwan, June 2023. All accepted papers will be published in the conference proceedings. Selected papers will be recommended to Applied Sciences for a Special Issue publication, and full conference paper will not be published in IS3C 2023.

The scope of interest for the proposed Special Issue includes, but is not limited to:

  • Medical image and signal processing with intelligent and fuzzy methods;
  • Smart imaging, microwave, and optical hardware and/or software for medical image and signal acquisition;
  • Automated visual inspection in medical images and signals;
  • Fractional-order calculus for image and signal processing;
  • Handwriting, face, and gesture recognition with intelligent and fuzzy methods;
  • Video and image analysis with intelligent and fuzzy methods;
  • Fault detection in smart manufacturing management system;
  • Visual inspection or search in smart manufacturing management system;
  • Smart management system with specific hardware and/or software techniques;
  • Chaotic synchronous communication and chaotic system for document and image encryption and decryption;
  • Deep learning and machine learning method with the evolutionary computation for above-mentioned topics.

Prof. Dr. Chia-Hung Lin
Prof. Dr. Neng-Sheng Pai
Prof. Dr. Chao-Lin Kuo
Prof. Dr. Chang-Hua Lien
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Applied Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (12 papers)

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Research

18 pages, 4339 KiB  
Article
Experimental Study on Colpitts Chaotic Oscillator-Based Communication System Application for the Internet of Things
Appl. Sci. 2024, 14(3), 1180; https://doi.org/10.3390/app14031180 - 31 Jan 2024
Viewed by 449
Abstract
This manuscript presents an experimental study of Quadrature Chaos Shift Keying (QCSK) as a means to tighten the physical layer security of Internet of Things (IoT) communication. Our study examines the characteristics and operational aspects of chaos oscillators, prioritizing low-power functionality, resilient chaotic [...] Read more.
This manuscript presents an experimental study of Quadrature Chaos Shift Keying (QCSK) as a means to tighten the physical layer security of Internet of Things (IoT) communication. Our study examines the characteristics and operational aspects of chaos oscillators, prioritizing low-power functionality, resilient chaotic oscillations, and resistance to parameter variations and noise. This study emphasizes the key role of chaos oscillators in enhancing IoT security, showcasing their potential to ensure data integrity. The findings elucidate the dynamics and synchronization stability of the selected oscillators, providing insights into their suitability for secure communication systems. This comprehensive analysis contributes to advancing secure communication methodologies for the expanding landscape of wireless sensor networks in the Internet of Things, underscoring the significance of chaos oscillators in ensuring robust and secure data transmission. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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20 pages, 17599 KiB  
Article
Synchronization of Analog-Discrete Chaotic Systems for Wireless Sensor Network Design
Appl. Sci. 2024, 14(2), 915; https://doi.org/10.3390/app14020915 - 21 Jan 2024
Viewed by 536
Abstract
The current work is focused on studying the performance of the Pecora–Carroll synchronization technique to achieve synchronization between the analog and discrete chaos oscillators. The importance of this study is supported by the growing applications of chaotic systems for improving the security of [...] Read more.
The current work is focused on studying the performance of the Pecora–Carroll synchronization technique to achieve synchronization between the analog and discrete chaos oscillators. The importance of this study is supported by the growing applications of chaotic systems for improving the security of data transmission in various communication layers, primarily on the physical layer. The hybrid analog-discrete approach of implementing chaos oscillators opens new possible communication schemes for wireless sensor network (WSN) applications. The analog implementation of chaos oscillators can benefit the simpler sensor node (SN) integration, while the discrete implementation can be used on the gateway. However, the core of such chaos-based communications is synchronizing analog and discrete chaos oscillators. This work studies two key parameters of analog-discrete chaotic synchronization: chaotic synchronization noise immunity and synchronization speed. The noise immunity study demonstrates the quality of synchronization at various noise levels, while the synchronization speed demonstrates how quickly the analog-discrete synchronization is achieved, along with how quickly the two systems diverge when synchronization is no longer present. The two studies use both simulation-based and hardware-based approaches. In the simulation case, the analog oscillator’s circuit is modeled in LTspice XVII, while in the hardware case, the circuit is implemented on the PCB. In both simulation and hardware studies, the discrete model of the oscillator is implemented in MATLAB R2023b. The studies are performed for two pairs of different chaos oscillators to widen the proposed approach application potential: the Vilnius and RC chaos oscillators. The oscillators have been selected due to their simplicity and similar dynamic behavior for model-based and electrical circuit implementation. The proposed approach also allows us to compare the synchronization of different oscillators in the analog-discrete implementation. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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15 pages, 4638 KiB  
Article
Modeling, Prediction, and Results Correction of PDSH Circuits for Nanosecond Pulse Peak Detection
Appl. Sci. 2023, 13(23), 12597; https://doi.org/10.3390/app132312597 - 22 Nov 2023
Viewed by 696
Abstract
The peak detect and sample hold (PDSH) circuit is an important component of the light detection and ranging (LiDAR) system, because the PDSH circuit can correct the walk error of the time discriminator, and distinguish different objects at the same location. However, due [...] Read more.
The peak detect and sample hold (PDSH) circuit is an important component of the light detection and ranging (LiDAR) system, because the PDSH circuit can correct the walk error of the time discriminator, and distinguish different objects at the same location. However, due to the requirement for high-precision measurement of nanosecond-scale pulse signals, the design of the PDSH circuit presents significant challenges. This paper accomplishes the modeling of the PDSH circuit, including the modeling of the PDSH measurement speed and the voltage step, quantifies various factors that affect the PDSH circuit measurement results, and makes predictions based on the model. Through the derivation and simplification of the rise process in the PDSH circuit, this study establishes a mathematical model to predict the performance of the PDSH circuit. Furthermore, this study also investigates the effect of circuit delay time on the measurement speed of the PDSH circuit. Meanwhile, this study analyzes the voltage step process, and an equivalent circuit model is derived through theoretical analysis. By utilizing a fitting method, the equivalent capacitance value of the diode is obtained. The simulation and experiment results show that the errors between the measurement speed model of the PDSH circuit and the actual circuit are no more than 1.98 ns and 2.03 ns, respectively. Thus, the measurement speed model can accurately predict whether the PDSH circuit meets the requirements. Moreover, the maximum absolute error of the equivalent circuit model is 19.87 mV, which can significantly reduce the error caused by the voltage step. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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28 pages, 5236 KiB  
Article
Prognostics of Electromechanical Actuator with Partial Time Scaling Invariant Temporal Alignment
Appl. Sci. 2023, 13(22), 12321; https://doi.org/10.3390/app132212321 - 14 Nov 2023
Cited by 1 | Viewed by 457
Abstract
In today’s industrial environment, effectively monitoring assets throughout their entire lifetime is essential. Prognostic and Health Management (PHM) is a powerful tool that enables users to achieve this goal. Recently, sensor-equipped actuator electrification has been introduced to capture intrinsic key system variables as [...] Read more.
In today’s industrial environment, effectively monitoring assets throughout their entire lifetime is essential. Prognostic and Health Management (PHM) is a powerful tool that enables users to achieve this goal. Recently, sensor-equipped actuator electrification has been introduced to capture intrinsic key system variables as time series. This data flow has opened up new possibilities for extracting essential maintenance information. To leverage the full potential of these data, we have developed a novel algorithm for time series registration, which serves as the core of a new similarity-based prognostic method in a PHM context: Partial Time Scaling Invariant Temporal Alignment for Remaining Useful Life Estimation (PARTITA-RULE). Our algorithm transforms acceleration signals into a subset of descriptors for a new actuator, creating a time series. We can extract valuable maintenance information by aligning this time series with the one already labeled from past behaviors of the same actuator’s family of heterogeneous sizes and robust scaling factors. The unique aspect of our method is that we do not need to inject prior knowledge for registration intervals at this stage. Once the unknown series is aligned with all possible candidates, we create a weighting scheme to assign a relevance score with an uncertainty measurement for each aligned pair. Finally, we compute interpolants on the Wasserstein space to obtain the asset’s Remaining Useful Life (RUL). It is important to note that a relevant result in a PHM context requires a database filled with different labeled system behaviors. To test the effectiveness of our method, we use an industrial data set of vibration signals captured on an aeronautical electric actuator. Our method shows promising Remaining Useful Life (RUL) estimation results even with incomplete time segments. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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18 pages, 4170 KiB  
Article
A Spatial Registration Method for Multi-UAVs Based on a Cooperative Platform in a Geodesic Coordinate Information-Free Environment
Appl. Sci. 2023, 13(19), 10705; https://doi.org/10.3390/app131910705 - 26 Sep 2023
Viewed by 454
Abstract
The satellite navigation system of Unmanned Aerial Vehicles (UAVs) is susceptible to external interference in a complex environment, resulting in the loss of their own geodetic coordinate information. A spatial registration method for multi-UAVs based on a cooperative platform in a geodesic coordinate [...] Read more.
The satellite navigation system of Unmanned Aerial Vehicles (UAVs) is susceptible to external interference in a complex environment, resulting in the loss of their own geodetic coordinate information. A spatial registration method for multi-UAVs based on a cooperative platform in a geodesic coordinate information-free environment is proposed to solve this problem. The mutual observation information between UAVs is approximated by the observation information of the cooperative platform. Indirect observation information of the target can be obtained on account of mutual observation. On the basis of this, a close-range spatial registration algorithm without the geodetic coordinate information of UAVs is designed by means of the right-angle translation method. Finally, the Kalman filtering technique is used to track maritime targets. In this paper, the proposed method is verified by a simulation experiment and a practical experiment. The proposed method is 90% effective in reducing systematic errors. The tracking accuracy after alignment is significantly better than that of the original trajectory. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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14 pages, 5591 KiB  
Article
Optimization of Data Acquisition System Based on Electrical Impedance Tomography in Dredging Engineering
Appl. Sci. 2023, 13(17), 9931; https://doi.org/10.3390/app13179931 - 02 Sep 2023
Viewed by 553
Abstract
Electrical impedance tomography (EIT) is an advanced visualization detection technique with non-invasive, radiationless, and fast-response characteristics. As an important means in dredging engineering, EIT-based measurement can realize the estimate and computation of key flow parameters such as the flow velocity and solid phase [...] Read more.
Electrical impedance tomography (EIT) is an advanced visualization detection technique with non-invasive, radiationless, and fast-response characteristics. As an important means in dredging engineering, EIT-based measurement can realize the estimate and computation of key flow parameters such as the flow velocity and solid phase fraction of solid-liquid two-phase flow in a pipe. Despite progress, both the data acquisition rate and the signal-to-noise ratio (SNR) of the existing EIT system are too low to meet many practical requirements. In this study, efforts are made concerning the EIT acquisition system by optimizing the sensor array, data acquisition system, and data communication module. Experimental results show that (1) the optimized system has an SNR of 73 dB, which is about 40% higher than the original system, and (2) the optimization of data transmission methods can achieve a maximum allowable transmission rate of 316.4 Mbps, sufficient to support data transmission over 1000 frames per second. Consequently, the key problems of the existing EIT acquisition system are substantially overcome. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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14 pages, 3605 KiB  
Article
Experimental Verification and Analysis of Vibration Damping Structure of Piezoelectric Ceramic Grain Loss Sensor
Appl. Sci. 2023, 13(9), 5477; https://doi.org/10.3390/app13095477 - 28 Apr 2023
Viewed by 1069
Abstract
In this study, in order to achieve accurate detection of grain loss during the process of combine harvester harvesting, a piezoelectric-based grain loss sensor has been developed. The sensor utilizes a double-layer circular piezoelectric ceramic sheet as its sensitive element. When different grains [...] Read more.
In this study, in order to achieve accurate detection of grain loss during the process of combine harvester harvesting, a piezoelectric-based grain loss sensor has been developed. The sensor utilizes a double-layer circular piezoelectric ceramic sheet as its sensitive element. When different grains come into contact with the sensitive element, the piezoelectric effect of the ceramic sheet generates corresponding charges. These charges are then converted into knock charge signals through a charge amplification signal processing circuit that has been specially designed for this purpose. The harsh operating conditions of the sensor, including the presence of significant vibration and noise interference, necessitate the incorporation of a double-layer vibration-damping structure in both the top and bottom layers of the sensor. This paper seeks to analyze the vibration-damping effect of various shock-absorbing materials and structures incorporated into the sensor. This is accomplished by creating a dynamic analysis model that accounts for vibration interference. Furthermore, an experimental bench is established for the purpose of verifying the vibration-damping test results. These tests demonstrate that the utilization of a properly selected vibration-damping structure and materials can effectively eliminate mechanical vibration and noise interference. This, in turn, leads to improved detection accuracy of charge signals after knocking and enhances the overall anti-interference ability of the sensor. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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22 pages, 8318 KiB  
Article
Control Strategy of Synchronous Reluctance Motor Using Empirical Information Brain Emotional Learning Based Intelligent Controller Considering Magnetic Saturation
Appl. Sci. 2023, 13(9), 5327; https://doi.org/10.3390/app13095327 - 24 Apr 2023
Viewed by 902
Abstract
The synchronous reluctance motor (SynRM) has significant nonlinear characteristics due to the problems of magnetic saturation and cross-coupling and the poor adaptability of the general controller to parameter changes seriously affects the control performance of the motor. In order to solve the above [...] Read more.
The synchronous reluctance motor (SynRM) has significant nonlinear characteristics due to the problems of magnetic saturation and cross-coupling and the poor adaptability of the general controller to parameter changes seriously affects the control performance of the motor. In order to solve the above problems, this paper proposed a control system for the SynRM with a brain emotion controller based on empirical information to solve the motor control problem of magnetic saturation. Firstly, the nonlinear mathematical model of the SynRM considering magnetic saturation is established by introducing the magnetic saturation parameter. Secondly, the sensory input function and emotional cue function based on systematic error are given and the vector control system of the SynRM considering magnetic saturation is designed. The influence of the parameters and the learning rate of the brain emotional learning based intelligent controller (EI-BELBIC) on the adjustment range of the controller parameters is studied. Then the SynRM is controlled under different working conditions and the control effect is observed. The results show that the designed vector control system of the SynRM based on EI-BELBIC has strong reliability, accurate control, rapid response, and strong anti-interference ability under magnetic saturation. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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12 pages, 1204 KiB  
Article
A Flexible and Simple Lossless DWT Filter Bank Using a MAXFLAT FIR Half-Band Filter
Appl. Sci. 2022, 12(18), 9166; https://doi.org/10.3390/app12189166 - 13 Sep 2022
Viewed by 922
Abstract
This paper describes a simple, lossless and computationally efficient two-band single (s-) filter bank that creates an opposite band output by subtracting the primary filtered data from the original data. For computationally efficient and error-free s-filter bank achievement, a maximally flat (MAXFLAT) half-band [...] Read more.
This paper describes a simple, lossless and computationally efficient two-band single (s-) filter bank that creates an opposite band output by subtracting the primary filtered data from the original data. For computationally efficient and error-free s-filter bank achievement, a maximally flat (MAXFLAT) half-band filter with zero odd-order coefficients is characterized from a unique perfect reconstruction condition, and an explicit impulse–response formula (for non-zero integer coefficients of even order) is derived in a closed form of the filter. The examples are shown to provide a complete and accurate solution for the design of such s-filter banks. In addition, the effectiveness of the proposed s-filter banks is clearly verified by comparing the lossless 5/3 and lossy 9/7 filter banks (in the JPEG2000). The simulation results show that the s-filter banks lead to better performance than the JPEG2000 filter banks using two filters although allowing low computational complexity of less than 50%. This new approach is shown to provide significant advantages over existing lossless discrete wavelet transform (DWT) filter banks in both design flexibility and computational complexity. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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29 pages, 14625 KiB  
Article
Redundant Robot with Pneumatic Artificial Muscles for Rehabilitation Works Using Iterative Learning Control
Appl. Sci. 2022, 12(17), 8419; https://doi.org/10.3390/app12178419 - 23 Aug 2022
Cited by 1 | Viewed by 1782
Abstract
This study aims to develop a multi-functional robotic arm with a multi-degree of freedom using a pneumatic artificial muscle cylinder as the main actuator, with a wearable function. While wearing the robotic arm, it has four degrees of freedom and can be used [...] Read more.
This study aims to develop a multi-functional robotic arm with a multi-degree of freedom using a pneumatic artificial muscle cylinder as the main actuator, with a wearable function. While wearing the robotic arm, it has four degrees of freedom and can be used as an upper limb rehabilitation aid to perform rehabilitation exercise tasks. The rotating axes are driven by pneumatic artificial muscle cylinders to ensure the safety and flexibility of the robot interaction. By integrating multiple pneumatic control valves and sensors with embedded interface cards, the control of pneumatic artificial muscle cylinders is performed, and the rehabilitation trajectory commands are planned through the kinematics of the robotic arm, and a closed-loop control system is established to enable the robotic arm to achieve the task of rehabilitation trajectory tracking. In the single-axis robotic arm controller experiment, it was found that the LMS-PID is superior to the conventional PID control method. In the control experiment of the robotic arm under the multi-axis recovery trajectory, the result showed that the training of drawing a circle on the wall could be successfully planned. In the multi-axis robotic tracking experiment under the rehabilitation trajectory, the result showed that the RMSE of the tracking trajectory decreased to 0.2444 and 0.2853. In the robotic arm joining/loading experiment, it was shown that the method of this study can withstand some loading effects. Moreover, this study introduces iterative learning control to improve the non-linear compensation and phase lag problems of the PID controller so that the robot arm can have a certain tracking accuracy under the round-trip robust trajectory. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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23 pages, 25616 KiB  
Article
Breast Lesions Screening of Mammographic Images with 2D Spatial and 1D Convolutional Neural Network-Based Classifier
Appl. Sci. 2022, 12(15), 7516; https://doi.org/10.3390/app12157516 - 26 Jul 2022
Cited by 1 | Viewed by 1210
Abstract
Mammography is a first-line imaging examination that employs low-dose X-rays to rapidly screen breast tumors, cysts, and calcifications. This study proposes a two-dimensional (2D) spatial and one-dimensional (1D) convolutional neural network (CNN) to early detect possible breast lesions (tumors) to reduce patients’ mortality [...] Read more.
Mammography is a first-line imaging examination that employs low-dose X-rays to rapidly screen breast tumors, cysts, and calcifications. This study proposes a two-dimensional (2D) spatial and one-dimensional (1D) convolutional neural network (CNN) to early detect possible breast lesions (tumors) to reduce patients’ mortality rates and to develop a classifier for use in mammographic images on regions of interest where breast lesions (tumors) may likely occur. The 2D spatial fractional-order convolutional processes are used to strengthen and sharpen the lesions’ features, denoise, and improve the feature extraction processes. Then, an automatic extraction task is performed using a specific bounding box to sequentially pick out feature patterns from each mammographic image. The multi-round 1D kernel convolutional processes can also strengthen and denoise 1D feature signals and assist in the identification of the differentiation levels of normality and abnormality signals. In the classification layer, a gray relational analysis-based classifier is used to screen the possible lesions, including normal (Nor), benign (B), and malignant (M) classes. The classifier development for clinical applications can reduce classifier’s training time, computational complexity level, computational time, and achieve a more accurate rate for meeting clinical/medical purpose. Mammographic images were selected from the mammographic image analysis society image database for experimental tests on breast lesions screening and K-fold cross-validations were performed. The experimental results showed promising performance in quantifying the classifier’s outcome for medical purpose evaluation in terms of recall (%), precision (%), accuracy (%), and F1 score. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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15 pages, 5687 KiB  
Article
An Underdetermined Convolutional Blind Separation Algorithm for Time–Frequency Overlapped Wireless Communication Signals with Unknown Source Number
Appl. Sci. 2022, 12(13), 6534; https://doi.org/10.3390/app12136534 - 28 Jun 2022
Viewed by 821
Abstract
It has been challenging to separate the time–frequency (TF) overlapped wireless communication signals with unknown source numbers in underdetermined cases. In order to address this issue, a novel blind separation strategy based on a TF soft mask is proposed in this paper. Based [...] Read more.
It has been challenging to separate the time–frequency (TF) overlapped wireless communication signals with unknown source numbers in underdetermined cases. In order to address this issue, a novel blind separation strategy based on a TF soft mask is proposed in this paper. Based on the clustering property of the signals in the sparse domain, the angular probability density distribution is obtained by the kernel density estimation (KDE) algorithm, and then the number of source signals is identified by detecting the peak points of the distribution. Afterward, the contribution degree function is designed according to the cosine distance to calculate the contribution degrees of the source signals in the mixed signals. The separation of the TF overlapped signals is achieved by constructing a soft mask matrix based on the contribution degrees. The simulations are performed with digital signals of the same modulation and different modulation, respectively. The results show that the proposed algorithm has better anti-aliasing and anti-noise performance than the comparison algorithms. Full article
(This article belongs to the Special Issue Advanced Electronics and Digital Signal Processing)
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