Some Simulation Results of 3D Imaging Based on Chirp Stepped-frequency Signal

Autofocus is a technique for improving inverse synthetic aperture radar (ISAR) imaging. In this paper, a novel autofocusing method is developed for high-resolution stepped-frequency ISAR. Non-uniform rotational motion is compensated through the proposed post-processing methodology. In this way, the computational cost of polar reformatting process can be circumvented. The proposed CPI-split autofocusing process results in well-focused ISAR images for high angular acceleration periods. Finally, ISAR image entropy dependencies are thoroughly examined through various simulation results, leading to an acceptable range of entropy values for the autofocusing process. Ill. 7, bibl. 9, tabl. 3 (in English; abstracts in English and Lithuanian).http://dx.doi.org/10.5755/j01.eee.110.4.305

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Parameter Estimation of Low-Frequency Signal with Negative Frequency Contribution

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.3457 ◽

2013 ◽

Vol 380-384 ◽

pp. 3457-3460 ◽

Cited By ~ 1

Author(s):

Si Wei Tan ◽

Zhi Liang Ren ◽

Jiong Sun

Keyword(s):

Parameter Estimation ◽

Phase Difference ◽

Spectrum Analysis ◽

Low Frequency ◽

High Accuracy ◽

Signal Parameter ◽

Frequency Signal ◽

Spectrum Method ◽

Analysis Theory ◽

Simulation Results

According to the problem that there is a decline in accuracy of low-frequency signal parameter estimation by using the algorithm of all-phase FFT, an improved phase difference correcting spectrum method based on all-phase FFT is proposed. The contribution of negative frequency to FFT calculation was considered while using phase difference correcting spectrum method. The all-phase FFT spectrum analysis theory was presented as well as a traditional phase difference correcting method based on it. The equations of parameter estimation such as frequency, amplitude and phase for low-frequency signals were derived with the negative frequency contribution to spectrum analysis. The simulation results show that the method proposed in this paper can be used to estimate the parameters of low-frequency signals in a high accuracy, and also achieves an improvement in anti-noise ability.

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The Distortion Analysis and Restraint of Dual-Frequency Modulation Signals

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.380-384.3599 ◽

2013 ◽

Vol 380-384 ◽

pp. 3599-3603

Author(s):

Yang Zhang ◽

Song Bai Hu ◽

Shi Hong Liu

Keyword(s):

The Self ◽

Far Field ◽

Square Root ◽

Dual Frequency ◽

Frequency Signal ◽

Distortion Analysis ◽

Signal Input ◽

Acoustic Array ◽

Simulation Results ◽

Square Root Method

According to the parametric acoustic array theory and Berktay far-field solution, analyze the self-demodulation distortion theory of the DSB method and the square root method with the dual-frequency signal input and present the distortion calculating formulas. Bring forward an adapting modulation algorithm, which can restrain over modulation effectively. Compared with theoretical analysis, the simulation results of MATLAB are satisfactory.

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Simulation of an Adaptive Method of Improving the Accuracy and Extending the Range of Frequency Signal Processing in a Frequency-to-Code Converter

Applied Sciences ◽

10.3390/app112110341 ◽

2021 ◽

Vol 11 (21) ◽

pp. 10341

Author(s):

Piotr Warda

Keyword(s):

Signal Processing ◽

Adaptive Method ◽

Variable Frequency ◽

Frequency Change ◽

Clock Signal ◽

Frequency Signal ◽

Frequency Selection ◽

Processing Error ◽

Simulation Results ◽

Selection Of

The article discusses the modification of one of the basic methods of converting successive periods of a variable frequency signal into numerical values representing them. The method performs the adaptive frequency selection of the clock signal in the system processing the consecutive periods of input signal. The signal processing error is analyzed on an ongoing basis, and the frequency change factor is selected. Algorithms describing the operation of the method are included. The program of the simulator of the measurement channel operation with a frequency carrier of information is described, which allows for the verification of the proposed method. Examples of the simulation results are included.

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Analysis and Compensation of Radial Motion Effect on Stepped Frequency Signal

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.427-429.1977 ◽

2013 ◽

Vol 427-429 ◽

pp. 1977-1980

Author(s):

Yao Tian Zhang ◽

Jia Jia Liu ◽

Yu Xian Zhang ◽

Miao Liu

Keyword(s):

Velocity Measurement ◽

Pulse Signal ◽

Radial Motion ◽

Frequency Signal ◽

Motion Effect ◽

Stepped Frequency

Stepped frequency signal is an important high distance resolution signal, this property is realized by combining several pulse signal, so it is easy to be effected by targets radial motion. Here we analyzed how targets radial motion affects the synthesis HRRP, then a method of velocity measurement is provided, then compensation using the predicted velocity.

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The Analysis of Rogowski Coil Transfer Characteristics in the Composite Frequency Environment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.816-817.450 ◽

2013 ◽

Vol 816-817 ◽

pp. 450-453

Author(s):

Hai Bao ◽

Xin Yuan Guo ◽

Ling Wang ◽

Gang Liu

Keyword(s):

Frequency Characteristic ◽

Rogowski Coil ◽

Frequency Characteristics ◽

Reference Standard ◽

Frequency Signal ◽

Transfer Ratio ◽

Transfer Characteristics ◽

Simulation Results ◽

Secondary Side

This article uses the method of frequency characteristic to analysis transfer characteristics of Rogowski coil. In the case of the composite frequency signal, Rogowski coil transfer ratio is the function of frequency, that is the transfer ratio varies with the frequency, which makes the signal of the secondary side not restore to the primary side. The simulation results prove the conclusion. In view of the situation, this paper presents an ideal transfer ratio, which provides the reference standard for correcting the frequency characteristics of the Rogowski coil integrating circuit.

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The Research Methodology of AR Spectrum Estimation to Stepped-Frequency Signal Processing

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.313-314.1243 ◽

2013 ◽

Vol 313-314 ◽

pp. 1243-1246

Author(s):

Jian Bai ◽

Wei Zhang ◽

Hou Jun Sun

Keyword(s):

Signal Processing ◽

High Resolution ◽

Research Methodology ◽

Linear Prediction ◽

Ar Model ◽

Spectrum Estimation ◽

Frequency Signal ◽

Range Profile ◽

Stepped Frequency ◽

High Resolution Range Profile

This paper uses modern spectrum setimation to process stepped-frequency signals which have extracted to obtain high resolution range profile. This paper use FPE criteria and AIC criteria to estimate the order of AR model, and linear prediction is used to test the performance of AR model. Compared with conventional IFFT processing, the results of spectrum estimation is satisfactory, and the exact location of high resolution range profile is determined.

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