scholarly journals Multiple Narrowband Interferences Characterization, Detection and Mitigation Using Simplified Welch Algorithm and Notch Filtering

2021 ◽  
Vol 11 (3) ◽  
pp. 1331
Author(s):  
Mohammad Hossein Same ◽  
Gabriel Gleeton ◽  
Gabriel Gandubert ◽  
Preslav Ivanov ◽  
Rene Jr Landry
Keyword(s):  
Power Spectrum ◽  
Embedded System ◽  
Radio Frequency ◽  
Satellite Communication ◽  
Signal To Noise Ratio ◽  
Center Frequency ◽  
Infinite Impulse Response ◽  
Frequency Variation ◽  
Welch Method ◽  
The Embedded System

By increasing the demand for radio frequency (RF) and access of hackers and spoofers to low price hardware and software defined radios (SDR), radio frequency interference (RFI) became a more frequent and serious problem. In order to increase the security of satellite communication (Satcom) and guarantee the quality of service (QoS) of end users, it is crucial to detect the RFI in the desired bandwidth and protect the receiver with a proper mitigation mechanism. Digital narrowband signals are so sensitive into the interference and because of their special power spectrum shape, it is hard to detect and eliminate the RFI from their bandwidth. Thus, a proper detector requires a high precision and smooth estimation of input signal power spectral density (PSD). By utilizing the presented power spectrum by the simplified Welch method, this article proposes a solid and effective algorithm that can find all necessary interference parameters in the frequency domain while targeting practical implantation for the embedded system with minimum complexity. The proposed detector can detect several multi narrowband interferences and estimate their center frequency, bandwidth, power, start, and end of each interference individually. To remove multiple interferences, a chain of several infinite impulse response (IIR) notch filters with multiplexers is proposed. To minimize damage to the original signal, the bandwidth of each notch is adjusted in a way that maximizes the received signal to noise ratio (SNR) by the receiver. Multiple carrier wave interferences (MCWI) is utilized as a jamming attack to the Digital Video Broadcasting-Satellite-Second Generation (DVB-S2) receiver and performance of a new detector and mitigation system is investigated and validated in both simulation and practical tests. Based on the obtained results, the proposed detector can detect a weak power interference down to −25 dB and track a hopping frequency interference with center frequency variation speed up to 3 kHz. Bit error ratio (BER) performance shows 3 dB improvement by utilizing new adaptive mitigation scenario compared to non-adaptive one. Finally, the protected DVB-S2 can receive the data with SNR close to the normal situation while it is under the attack of the MCWI jammer.

Enhancement of signal quality in esophageal recordings of diaphragm EMG

1997 ◽  
Vol 82 (4) ◽  
pp. 1370-1377 ◽  
Author(s):  
Christer A. Sinderby ◽  
Jennifer C. Beck ◽  
Lars H. Lindström ◽  
Alejandro E. Grassino
Keyword(s):  
Power Spectrum ◽  
Signal To Noise Ratio ◽  
Electrode Array ◽  
Center Frequency ◽  
Signal Quality ◽  
Fiber Direction ◽  
Bipolar Electrode ◽  
Subtraction Technique ◽  
Emg Power Spectrum ◽  
Crural Diaphragm

Sinderby, Christer A., Jennifer C. Beck, Lars H. Lindström, and Alejandro E. Grassino. Enhancement of signal quality in esophageal recordings of diaphragm EMG. J. Appl. Physiol. 82(4): 1370–1377, 1997.—The crural diaphragm electromyogram (EMGdi) is recorded from a sheet of muscle, the fiber direction of which is mostly perpendicular to an esophageal bipolar electrode. The region from which the action potentials are elicited, the electrically active region of the diaphragm (EARdi) and the center of this region (EARdi ctr) may vary during voluntary contractions in terms of their position with respect to an esophageal electrode. Depending on the bipolar electrode’s position with respect to the EARdi ctr, the EMGdi is filtered to different degrees. The objectives of the present study were to reduce these filtering effects on the EMGdi by developing an analysis algorithm referred to as the “double-subtraction technique.” The results showed that changes in the position of the EARdi ctr by ±5 mm with respect to the electrode pairs located 10 mm caudal and 10 mm cephalad provided a systematic variation in the EMG power spectrum center-frequency values by ±10%. The double-subtraction technique reduced the influence of movement of the EARdi ctr relative to the electrode array on EMG power spectrum center frequency and root mean square values, increased the signal-to-noise ratio by 2 dB, and increased the number of EMG samples that were accepted by the signal quality indexes by 50%.

Performance Evaluation of a Gammatone Filterbank for the Embedded System

2013 ◽  
Vol 336-338 ◽  
pp. 1459-1462 ◽  
Author(s):  
Yi Jiang ◽  
Yuan Yuan Zu ◽  
Xiao Chen ◽  
Hong Zhou
Keyword(s):  
Performance Evaluation ◽  
Embedded System ◽  
Automatic Speech Recognition ◽  
High Performance ◽  
Signal To Noise Ratio ◽  
Signal To Noise ◽  
Perceptual Evaluation ◽  
The Embedded System ◽  
Embedded Applications ◽  
Low Complex

A structured gammatone filterbank is proposed to decompose the mixture acoustic signal for the embedded system. The performance of the gammatone filterbank with various filter channels is evaluated by signal to noise ratio (SNR), perceptual evaluation of speech quality (PESQ) and automatic speech recognition (ASR) accuracy. As a detailed analysis shown, the gammatone filterbank with 24 channels is good for most embedded applications with a low complex and high performance at the same time.

scholarly journals The Design of a 2D Graphics Accelerator for Embedded Systems

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 469
Author(s):  
Hyun Woo Oh ◽  
Ji Kwang Kim ◽  
Gwan Beom Hwang ◽  
Seung Eun Lee
Keyword(s):  
Embedded Systems ◽  
Embedded System ◽  
Real Time ◽  
Line Drawing ◽  
Cmos Process ◽  
Embedded Processor ◽  
Processor Core ◽  
Field Programmable ◽  
The Embedded System ◽  
Graphics Processing

Recently, advances in technology have enabled embedded systems to be adopted for a variety of applications. Some of these applications require real-time 2D graphics processing running on limited design specifications such as low power consumption and a small area. In order to satisfy such conditions, including a specific 2D graphics accelerator in the embedded system is an effective method. This method reduces the workload of the processor in the embedded system by exploiting the accelerator. The accelerator assists the system to perform 2D graphics processing in real-time. Therefore, a variety of applications that require 2D graphics processing can be implemented with an embedded processor. In this paper, we present a 2D graphics accelerator for tiny embedded systems. The accelerator includes an optimized line-drawing operation based on Bresenham’s algorithm. The optimized operation enables the accelerator to deal with various kinds of 2D graphics processing and to perform the line-drawing instead of the system processor. Moreover, the accelerator also distributes the workload of the processor core by removing the need for the core to access the frame buffer memory. We measure the performance of the accelerator by implementing the processor, including the accelerator, on a field-programmable gate array (FPGA), and ascertaining the possibility of realization by synthesizing using the 180 nm CMOS process.

scholarly journals Identification and authentication for wireless transmission security based on RF-DNA fingerprint

2019 ◽  
Vol 2019 (1) ◽  
Author(s):  
Xueli Wang ◽  
Yufeng Zhang ◽  
Hongxin Zhang ◽  
Xiaofeng Wei ◽  
Guangyuan Wang
Keyword(s):  
Radio Frequency ◽  
Classification Accuracy ◽  
Signal To Noise Ratio ◽  
Additive White Gaussian Noise ◽  
Wireless Transmission ◽  
Dna Fingerprint ◽  
Support Vector ◽  
Multiple Discriminant Analysis ◽  
Security Issue ◽  
Rf Devices

Abstract For wireless transmission, radio-frequency device anti-cloning has become a major security issue. Radio-frequency distinct native attribute (RF-DNA) fingerprint is a developing technology to find the difference among RF devices and identify them. Comparing with previous research, (1) this paper proposed that mean (μ) feature should be added into RF-DNA fingerprint. Thus, totally four statistics (mean, standard deviation, skewness, and kurtosis) were calculated on instantaneous amplitude, phase, and frequency generated by Hilbert transform. (2) We first proposed using the logistic regression (LR) and support vector machine (SVM) to recognize such extracted fingerprint at different signal-to-noise ratio (SNR) environment. We compared their performance with traditional multiple discriminant analysis (MDA). (3) In addition, this paper also proposed to extract three sub-features (amplitude, phase, and frequency) separately to recognize extracted fingerprint under MDA. In order to make our results more universal, additive white Gaussian noise was adopted to simulate the real environment. The results show that (1) mean feature conducts an improvement in the classification accuracy, especially in low SNR environment. (2) MDA and SVM could successfully identify these RF devices, and the classification accuracy could reach 94%. Although the classification accuracy of LR is 89.2%, it could get the probability of each class. After adding a different noise, the recognition accuracy is more than 80% when SNR≥5 dB using MDA or SVM. (3) Frequency feature has more discriminant information. Phase and amplitude play an auxiliary but also pivotal role in classification recognition.

Reform of embedded system experiment course based on engineering education accreditation

2020 ◽  
pp. 002072092091815
Author(s):  
Yong Luo ◽  
Shuai-Bing Qin ◽  
Dong-Shu Wang
Keyword(s):  
Education Reform ◽  
Embedded System ◽  
Engineering Education ◽  
Assessment Method ◽  
Teaching Model ◽  
Electronic Information ◽  
Course Content ◽  
Practical Operation ◽  
System Experiment ◽  
The Embedded System

With the continuous development of engineering education accreditation in China, its concept has had a profound impact on the reform of various majors in higher education. Using the idea of engineering education accreditation, this paper discusses the main problems in the implementation of embedded experimental courses of electronic information majors and proposes related education reform programs. Taking the embedded system experiment course of the automation major and embedded system major of Zhengzhou University as examples, the course has carried out research on the aspects of teaching model, experimental course content, scientific assessment method, etc., and proposed corresponding improvement methods to achieve better effect. The practical operation result has proved that the embedded system experiment course of the automation major and embedded system major improved the students’ ability and met the requirements of professional accreditation.

Structure of an Embedded System Software Platform for Plate Recognition System Based on Applied Mechanics

2012 ◽  
Vol 460 ◽  
pp. 266-270
Author(s):  
Xing Wu Sun ◽  
Yu Chen ◽  
Ai Fei Wang
Keyword(s):  
Embedded System ◽  
Recognition System ◽  
Cmos Camera ◽  
Camera System ◽  
New Thought ◽  
Development Platform ◽  
Embedded Linux System ◽  
Acquisition Device ◽  
The Embedded System ◽  
And Control

According to the shortcomings of large volume and high cost about the plate recognition system, an embedded plate recognition system is developed based on the ARM11 processor at lower costs. Taking the embedded Linux system as the software development platform, the system uses graphical user interface to operate and control the machine. Using CMOS camera system as image acquisition device, the system adopts HSV algorithm to realize the image classification on the platform of the embedded plate recognition system. The experimental results show that the embedded system runs stably, can realize the plate classification by color, and has the advantages of small size, low power consumption, convenience for using and so on. The embedded system provides a new thought for plate recognition.

Design and Implementation of Contour Tracing Image Recognition System

2014 ◽  
Vol 543-547 ◽  
pp. 2209-2212
Author(s):  
Chun Hua Xiong ◽  
You Jie Zhou ◽  
Gao Jun An ◽  
Chang Bo Lu
Keyword(s):  
Embedded System ◽  
Image Recognition ◽  
Integrated Design ◽  
Recognition System ◽  
Image System ◽  
Intelligent Monitoring ◽  
Contour Tracing ◽  
The Embedded System ◽  
Imaging Sensor ◽  
Very High

Based on the existing contour tracing image recognition technology, combining the embedded system technology and the computer storage control technology, the author makes an integrated design, adopts the image processing chip, USB controller, the imaging sensor and other hardware circuits and develops an intelligent image system. The system can make real-time monitoring the size and change of millimeter-sized irregular target objects. Its applicable value in the fields such as intelligent monitoring of oil equipment, medical imaging and criminal investigation is very high.

Design and Implementation of Spurs Detection System Based on OpenCV

2011 ◽  
Vol 345 ◽  
pp. 217-222
Author(s):  
Peng He ◽  
Lian Peng Wang ◽  
Na Wang ◽  
Gang Xu
Keyword(s):  
Computed Tomography ◽  
Embedded System ◽  
Detection System ◽  
Experimental Results ◽  
Design And Implementation ◽  
Function Expansion ◽  
The Embedded System ◽  
Improved Function ◽  
Small Bone ◽  
Improved Algorithm

In order to better solve the problem of detection of small bone spurs with convenient and accurate way, a portable spur detection system is designed. This system, in view of spur reproducibility characteristic, is characterized by the application for a kind of the improved algorithm based on the OpenCV. And it was successfully transplanted into the embedded system. The experimental results indicated that this system might precisely examine the small spur with difficulty discovery by naked eyes used fully by two images of computed tomography which done in different periods. The spur detection system needs to be further improved function to realize more applications. In fact, function expansion based on the system is easy to realize.

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