Abstract:

Existing bistatic Synthetic Aperture Radar(BiSAR) imaging methods simplify all targets in the scene as the superposition of point targets, ignoring the complex scattering processes of the targets. This leads to model mismatch in the imaging echoes and the loss of structural information of the targets in the imaging results. To address this issue, a BiSAR target parametric imaging method based on target scattering feature parameter estimation is proposed. Firstly, a BiSAR parametric echo model is established based on the ideal point scattering model and three typical target scattering models. Secondly, the position parameters are estimated using the coarse imaging results, and a local dictionary matrix is constructed based on the parametric echo model to achieve dictionary dimensionality reduction. Then, the Alternating Direction Method of Multipliers(ADMM) is utilized to estimate the target scattering feature parameters. Finally, the image is parametrically reconstructed based on the estimated target parameters. Experiments with simulated data validate the accuracy and effectiveness of the proposed method, which can enhance the structural information of the targets in the imaging results.

Abstract:

Aiming at the problem of weak target detection in traditional single-site radar, an integrated target detection and parameter estimation algorithm based on distributed waveform diversity array radar is proposed. The distributed waveform diversity array radar system consists of Frequency Diverse Array(FDA)-Multiple Input Multiple Output(MIMO) radar and Element Pulse Coding(EPC)-MIMO radar. Under the background of white noise, a binary hypothesis problem is constructed for each local radar station, where the target angle and distance information are unknown. Based on the above model, an adaptive detector is designed under the Generalized Likelihood Ratio Test(GLRT) criterion. The Coordinate Descent(CD) method and Gradient Projection Method(GPM) are employed to solve the estimates of target angle and distance information and obtain local detection statistics. Subsequently, at the fusion center, the global detection statistic for the final detection decision is constructed by calculating the logarithmic sum of multiple sets of local detection statistics. Simulation experiments verify that compared with single-site waveform diversity array radar, the distributed waveform diversity array radar improves the target detection probability. Compared with distributed phased array radar, the distributed waveform diversity array radar significantly enhances the target detection probability and parameter estimation performance.

Abstract:

To meet the demanding requirements of land and ocean observation under harsh and hazardous conditions, a compact, cost-effective, high-precision interferometric miniature Synthetic Aperture Radar(MiniSAR) system tailored for low, slow and small(LSS) platforms is proposed. Leveraging the unique characteristics and advantages of LSS platforms, the imaging modes, parameter design, and system architecture of the MiniSAR are discussed. In addition, the key technical challenges inherent to the MiniSAR system are analyzed, classified, and thoroughly evaluated. The findings provide both a theoretical foundation and technical support for system development, while offering valuable guidance for the design of lightweight, low-power MiniSAR solutions.

Abstract:

With the global deployment of the BeiDou navigation system, Passive Radar(PR) has gained access to all-weather, continuous, and wide-coverage opportunistic signals, demonstrating significant potential for maritime surveillance. However, the extremely low signal-to-noise ratio and nonlinear spatio-temporal variations challenge the effectiveness of conventional radar localization and tracking methods. A Joint Localization and Tracking(JLT) method is proposed for maritime targets by fusing multi-satellite illuminators. The approach involves long-time coherent integration of echoes into the Difference Bistatic Range(DBR),Doppler Centroid(DC),and Doppler Frequency Rate(DFR) domain. Leveraging the consistency of DFR, the multi-static results are projected and non-coherently fused in the X- Y- V _r domain to achieve initial target localization and velocity estimation. Subsequently, a Particle Filter(PF) is employed to address the nonlinear measurement model of PR, enabling precise multi-satellite tracking of moving targets. Simulation results confirm that the proposed method enhances the performance of state estimation and significantly reduces trajectory estimation errors.

Abstract:

Gesture recognition using millimeter-wave(mmWave) radar offers advantages such as contact-free operation, high detection accuracy, privacy preservation, and robust environmental adaptability, making it promising for industrial human-machine interaction and smart-home applications. However, existing mmWave-based dynamic-gesture recognition approaches suffer from high model complexity, large computational cost, low accuracy, and slow inference speed. To address these challenges, a lightweight gesture-recognition method is proposed based on an improved MobileViT network that maintains high accuracy while significantly reducing computational complexity for deployment on embedded devices. Firstly, dynamic-gesture echoes are captured with an mmWave radar. After suppressing device noise and background clutter, the data are reorganized into a 3-D matrix(sample points×chirps×frames). Range-time and Doppler-time maps are then generated via Fourier transform and fed into the enhanced MobileViT model for feature extraction and fusion, yielding the final gesture classification. Experimental results show that the proposed MobileViT model has only 0.167 M of parameter space complexity and 0.253 GFLOPs of computational complexity. Evaluated on a 12-class dynamic-gesture dataset, the method achieves 99.31% of recognition accuracy, demonstrating its effectiveness.

Abstract:

To further exploit the dual advantages of spatial diversity and waveform diversity in distributed frequency diverse array radar, a joint optimization method for transmit and receive parameters of distributed frequency diverse array radar based on the Maximum Block Improvement-Minorize Maximization(MBI-MM) is proposed. This method enhances the radar system's detection performance by jointly designing the transmit frequency offsets and receive filters of each radar station. Firstly, an optimization function is constructed to maximize the Signal-to-Interference-plus-Noise Ratio(SINR) of the target output in the clutter background, with constraints imposed on the frequency offsets and receive filters. Then, the original problem is decomposed into two independent subproblems, which are solved alternately. Finally, the MBI method is employed to iteratively update the optimization solutions of the two subproblems until the objective function converges. Simulations demonstrate that the joint optimization of frequency offsets and receive filters can significantly improve the SINR of the target output in the clutter background. Specifically, the target output SINR is improved by 5.7 dB when only the frequency offsets are optimized compared to when only the receive filters are optimized. After the joint optimization of transmit and receive parameters, the target output SINR is increased by 7.2 dB compared to when only the receive filters are optimized, and by an additional 1.5 dB compared to when only the frequency offsets are optimized. The proposed method enhances the radar's target detection performance in complex backgrounds for specific areas.

Abstract:

Terahertz(THz) Quantum Cascade Lasers(QCLs) are semiconductor devices based on intersubband electron leaps, which are characterized by small size, lightweight, easy integration, tunable frequency and high energy conversion efficiency, and have become one of the hotspots of current research. At present, THz QCLs have not appeared high-performance devices, and electron transport, as the most basic and fundamental starting point of THz QCLs, is an important way to break through this bottleneck. In this paper, the research progress in electron transport for THz QCLs is sorted out. Firstly, the influence of various scattering on the performance of THz QCLs is discussed. Secondly, the method to improve the operating temperature of QCLs through the optimized design of active region is also introduced. Finally, the research on electron transport of THz QCLs is outlooked. This work shows certain reference significance for improving the performance and application of THz QCLs.

Abstract:

Dielectric characterization of materials is crucial for accurately assessing their terahertz electromagnetic properties and ensuring their effectiveness in relevant applications. A method is proposed for dielectric property testing of Materials Under Test(MUT) based on their self-resonant characteristics, combining electronic terahertz technology with waveguide aperture reflection. The electromagnetic process and influencing factors of the self-resonance of the MUT at the rectangular waveguide aperture are clarified using the Finite-Difference Time-Domain(FDTD) method for electromagnetic field numerical analysis. Subsequently, the relationship between the waveguide reflection coefficient and the dielectric properties of the MUT is obtained. Based on the frequency shift of the material's self-resonance, grooves and etched channels are created on a single-crystal silicon wafer which is then bonded with polydimethylsiloxane(PDMS) to measure the dielectric properties of the liquid within the channels. Finally, a testing system with a single-crystal silicon wafer as the MUT is constructed in the laboratory according to the simulation rules, verifying the reliability of the simulation results and the feasibility of the proposed dielectric testing method.

Abstract:

In order to obtain the microscopic characteristics inside the lightning channel, a lightning dual band optical observation system is designed. The system mainly consists of a signal capture module, a signal reception and conditioning module, a signal acquisition module, and a power supply module. The transmission coefficient of the system can be calibrated by using a standard light source. The system can directly observe the time-domain full wave waveforms of different wavelength optical signals, and can analyze the temperature and conductivity information of channels through relative spectral line intensity. Based on the similarity between gap discharge and lightning, the designed system is employed to observe the gap discharge channel, and the temperature and conductivity of the gap discharge channel are calculated. The results indicate that the temperature variation range of the gap discharge channel in this experiment is 5 400~5 980 K, and the conductivity variation range is 10.93~28.53 S/m.

Abstract:

In the process of detecting the phase performance of the quiet zone in a compact range, it is necessary to eliminate the influence of the detection system on the measurement results in order to obtain the true performance of the site. Studies have shown that the detection phase error is caused by the installation offset of the scanning frame and the offset of the detection plane, and it exhibits certain regularities. In this paper, the installation offset of the scanning frame and the offset of the detection plane are calculated based on the phase measurement results of different sections of the quiet zone, and then compensation and correction are performed to eliminate the influence brought by the deviation of the detection system's measurement trajectory from the ideal path. This method is simple, reliable, and capable of obtaining real and effective detection results, which has been applied to the performance detection of the quiet zone in a compact range.

Abstract:

The electromagnetic environment of the working frequency band of High-Frequency Surface Wave Radar(HFSWR) is extremely complex. Noise, including radio frequency interference, sea clutter, and ionospheric clutter, can severely affect the accuracy of ship target identification. To address this issue, an improved feedforward Denoising Convolutional Neural Network(DnCNN) is proposed to suppress the noise in HFSWR marine echo signals. Based on the characteristics of the noise in HFSWR marine echo signals, the original DnCNN is modified in terms of patch size, convolutional kernel size, and network depth to make it suitable for the HFSWR denoising task. A dataset containing 10 000 pairs of Range-Doppler(RD) spectra is generated based on HFSWR sea trial data and is evenly divided into training and testing sets. Analysis of the denoising results of three groups of RD spectra in the testing set(with sea clutter, radio frequency interference, and ionospheric clutter as the main noise sources, respectively) shows that the improved DnCNN model significantly outperforms the original DnCNN in both noise suppression and maintaining the amplitude of ship target signals. Moreover,statistical results of the entire testing set indicate that the Peak Signal-to-Noise Ratio(PSNR) of the improved DnCNN denoising metric is 44.13 dB on average, which is significantly higher than the 35.58 dB of the original DnCNN. In summary, the improved DnCNN effectively suppresses the noise in HFSWR marine echoes while well preserving the amplitude of ship target signals.

Abstract:

To address the high computational complexity and low combining gain of conventional multi-antenna joint reception algorithms under low-SNR(Signal-to-Noise Ratio) conditions, a time-frequency phase-difference compensation-based multi-antenna joint signal-reception and combining algorithm is proposed. Building on the Semi-Implicit Method for Pressure Linked Equations(SIMPLE) framework applied to the Cross-Ambiguity Function(CAF) and phase-difference estimation, the algorithm first performs phase-error correction and then applies weighted combining, effectively lowering the computational burden on the signal-processing hardware. Simulation and experimental results demonstrate that, for two-channel signals exhibiting time-frequency phase differences, the proposed algorithm achieves perfect post-compensation alignment, confirming its feasibility. Under practical SNRs of 7 dB and 9 dB, the measured receive gain improves by approximately 2.76 dB, and the joint reception gain reaches 92% of the theoretical maximum, delivering the high post-combining gain required and significantly enhancing the reception of extremely weak signals. The approach offers a novel solution for acquiring ultra-faint deep-space signals.

Abstract:

To achieve accurate monitoring of electrical faults in propane dehydrogenation units, an automated noise-exceedance detection technique based on multi-channel acoustic-signal denoising is proposed. Using an Advanced Reduced Instruction Set Computer(ARM) platform, the system assesses noise levels within the units in real-time while capturing sound signals via a multi-channel acquisition scheme. An improved Ensemble Empirical Mode Decomposition(EEMD) method, aided by information fusion, is employed for multi-channel denoising.Wavelet-packet analysis is then applied to extract acoustic features, which are subsequently normalized. A multi channel Convolutional Neural Network(CNN) is constructed to model electrical-fault detection for the propane dehydrogenation units. Experimental results demonstrate that the proposed technique effectively monitors and denoises electrical noise, raising automatic monitoring accuracy to above 0.8.

Abstract:

Aiming at the problem that the failures of overvoltage protection device are difficult to identify under different levels of noise, and that failure details and device color information are hard to distinguish, a method for automated recognition of the failures of overvoltage protection device based on infrared imaging and Support Vector Machine(SVM) has been studied. Infrared imaging technology is employed to generate infrared thermal images of the overvoltage protection devices. An infrared thermal image enhancement method based on multi-scale Retinex is employed to improve the images. A fault feature extraction method based on wavelet transform is adopted to obtain the fault features of the overvoltage protection devices. A binary tree algorithm is applied to optimize the SVM, resulting in an SVM binary tree classification model. Automated recognition of the failures of overvoltage protection device is achieved through model training and solving. Experimental results show that the enhanced infrared thermal images of the overvoltage protection devices retain good detail and color information, with a Peak Signal-to-Noise Ratio(PSNR) increased by more than 50 dB. The extracted fault features of the overvoltage protection devices have good separability. The automated recognition match rate of the failures of overvoltage protection device under different noise levels remains above 96%, allowing for accurate identification of the failures.

Abstract:

Effective choice of the solution is essential to achieve a real-time, bi-directional(full- duplex) communication of the smart grid. The Power Line Carrier(PLC) technology provides a low-cost solution, which suits China's own national conditions. In this paper, the advantages of OFDM PLC modulation technology are introduced. A PLC module of system model is established through the analysis of the input impedance under the low-voltage power line channel. The high-speed PLC module based on low-voltage Power Line is also designed according to the studies of power line channel. The results show that the design of the PLC module has featured high receiving sensitivity and anti-noise ability.

Abstract:

With the development of Internet applications, users’ demand for bandwidth is soaring sharply. Meanwhile，along with the development of broadband access technology, the endpoint can also adopt multiple network accesses. But due to one-way communication of traditional Transmission Control Protocol(TCP)，the waste of resources will exist. To this end，IETF has specifically proposed Multi-Path TCP(MPTCP) to implement TCP multiplexing，thereby enhancing the efficiency and robustness. This paper gives a review of the IETF’s research on MPTCP，including MPTCP architecture, routing and congestion control, aiming to provide a reference for deeply studying.

Abstract:

Traditional methods and instruments are not able to measure the true Root Mean Square(RMS) of distortion sine wave or non-sine signal accurately. This article introduces a method to measure the true RMS of any high frequency signal by using the true RMS measurement IC，AD536A，designed by AD corporation. The paper analyses the difference between the RMS measured by the average measure method and the true RMS in theory. It explains the disadvantages of current RMS measure method，and presents the design of true RMS measure circuit. The experiment results prove that the proposed method and circuit can measure the true RMS of any high frequency signal accurately.

Abstract:

Terahertz(THz) optoelectronics has promoted the development of the THz generation, transparent control, and detection methods，and hastened many devices in the past decades. Especially, THz metamaterials and metasurfaces will exhibit extraordinary electromagnetic response when the subwavelength scale metal structure is excited by the THz illumination. Therefore, they have been applied to the devices such as wave beam shaper, waveguide, and modulator etc. The THz metamaterials and metasurfaces also show the potential applications in the research fields such as sensors, communications, and radars. In this paper, the works about the spectrum and wavefront modulation with THz metadevices carried out in our group are summarized. The basic theory and corresponding experiment results for different devices are introduced. It is expected these works can pave the avenue of the application of the THz metadevices.

Abstract:

Aiming at the problems in existing underground personnel positioning systems, an assisted positioning method based on pedestrian dead reckoning is proposed. Low-cost Inertial Measurement Unit(IMU) and magnetometer are employed to constitute a stable Attitude Heading Reference System (AHRS). The theory of inertial navigation is utilized, an algorithm for step detection is described, and Zero velocity Update(ZUPT) is adopted for velocity and position estimation to compose a pedestrian dead reckoning system. An experiment is performed in the corridor of a laboratory building to emulate the underground mine road environment. The experimental results demonstrate that the dead reckoning performs well and this method is an effective complement to existing underground positioning by improving the positioning accuracy.

Abstract:

The requirements for micro stress measurement of strain gauge are high precision，high linearity，high stability and high gain. One kind of differential amplifier circuit with excellent performance was designed. Some skillful techniques were adopted to avoid common voltage in the circuit and to reduce the temperature drift. The gain linearity is about 0.01%，and its Common-Mode Rejection Ratio(CMRR) is about 129 dB under work conditions.

Abstract:

The background requirements of the fuze antenna in terahertz spectrum as well as its advantages and disadvantages are introduced. The working principles and application characteristics of dielectric lens antenna in terahertz frequency are analyzed in order to implement the terahertz fuze antenna. The longitudinal size of H plane horn antenna can be reduced effectively by using fuze antenna formed by an H plane horn with dielectric lens antenna. The terahertz fuze antenna with different beam angles is achieved by focal technology of lens. The feasibility of the technology solution is verified through simulation.

Abstract:

According to the requirements of safe, simple and nondestructive radiation effect investigation of semiconductor devices, the method of laser simulation was proposed and greatly promoted. Compared with large-scale facilities, laser simulation has various unique advantages. It helps understand the ionization radiation effect in depth and is an effective low-cost, table-top supplement for the hardness assurance. Its research shows great significance for radiation effect study in both theory and practice. In this paper, the basic principles of the interactions of γ and laser with semiconductor devices are firstly presented. Then the physical basics and characteristics of laser simulation are given, with the research progress review followed. The existing problems of current research are deeply discussed providing with feasible research approaches. In the end, necessary research contents in the future are proposed.

Abstract:

Ultra-wideband(UWB) communication shows its advantages of fast data transfer(100 Mb/s or above) in a relatively short distance(typically below 10 m) with relatively weak power consumption (energy spectrum below -41.3 dBm/MHz). Integrated with Multiple Input Multiple Output(MIMO) technology, channel capacity could be further enhanced. As a critical link in the ultrawideband communication，UWB antenna needs extra efforts in design optimization to boost the performance of the whole system. UWB antenna is defined as the antenna whose bandwidth exceeds 500 MHz or relative bandwidth greater than 20%. This paper takes the most representative Vivaldi antenna as a show case for multi-objective optimization design with statistical methods. The optimized miniaturized antenna(sized130 mm×100 mm) shows a -10 dB bandwidth of 2.4 GHz. The design method provides guidance in common wideband，multi-parameter antenna design.

Abstract:

The design of code tracking loop is a key sector of the realization of noncoherent spectrum spread receiver. In order to realize the code tracking in noncoherent spectrum spread receiver, an energy-normalization digital delay-locked loop was designed, the structure of the loop and the calculating procedure of loop parameters were introduced. The characteristic of noncoherent spectrum spread was analyzed first，and then the key point of the loop design was pointed out. Based on this, the design and realization methods of code loop discriminator, loop filter, early and lag code generator were expatiated. A set of specific loop parameters were introduced as well. Modelsim simulation results and FPGA actual measured data prove the precise code tracking ability of the design.

Abstract:

Radio Frequency IDentification(RFID) series Radio Frequency(RF) card has been applied widely because of its stability，reliability and easy operation features. Aiming at multiple protocols，such as ISO14443 protocol，ISO15693 protocol and Tag-it protocol，this study proposed a new type of circuit design based on Advanced RISC Machine(ARM) for the RFID series RF card reader. The data stream encryption was implemented by using peripheral device in the operation. The system composition，working principle and work flow were introduced. Then，the detailed circuit design of the RF network and encryption hardware were presented，and the test and analysis for the design were performed. The results showed that the circuit could accurately read, write and encrypt various types of card within effective range.

Abstract:

The application of CORDIC(COordinate Rotation DIgital Computing) arithmetic in solving transcendental function has become popular in modern engineering. A brief introduction of CORDIC arithmetic was given in this study. Taking the hyperbolic sine and cosine functions as examples, the method of realizing the arithmetic in FPGA was presented and simulated on ISE(Integrated Software Environment) platform. The result showed this arithmetic was of good precision and instantaneity because of using pipeline. This arithmetic has great practical value in some applications. In addition, a curve of the relationship between the iterative number and the error obtained by the Matlab simulation of the arithmetic can help designers planning the number of iterations for practical applications.

Abstract:

The implementation of TCP/IP protocol stack on TM320DM642 platform could provide technological support for the application of multimedia embedded systems to networks. Both the function of TM320DM642 chip and the hierarchical structure of LWIP(Light Weight Internet Protocol) were analyzed. Network communications for TM320DM642 systems were implemented by the transplantation of LWIP, not by a solution scheme of NDK(Network Developer’s Kit). Testing examples verified the effectiveness of the LWIP transplanted method.

Abstract:

This article introduces a new type of high speed，multi-modulated digital modulator with adjustable center frequency and bit rate features. It can realize the Quadrature Phase Shift Keying(QPSK) and 16QAM(Quadrature Amplitude Modulation) with 80 MHz center frequency and 7.936 5 MHz bandwidth. The general-purpose modulation arithmetic based on software radio，symbol mapping and the realization of pulse shaping filter are discussed. The measuring results demonstrate that the modulation scheme meets the requirements of practicability and general utilization.

Abstract:

The Spatial Light Modulation(SLM) technology has been widely applied to the fields of threshold switch, high speed optical interconnection and optical logic operations, which demands good performance on the real-time and fast optical signal addressing. Compared with Electro-Addressing SLM(EA-SLM), Optically-Addressing SLM(OA-SLM) shows great advantages of fast speed and high resolution by parallel addressing. Nevertheless, how to achieve fast and stable optically addressing is the key point in practice. Based on ZnO thin film as a photoconductive layer, Liquid Crystal OASLM(LC-OASLM) is designed and fabricated; the modulation of the readout light intensity and phase distribution in the two-dimensional space is achieved effectively.

Abstract:

High-speed data acquisition system is an important component in modern radar signal processing. A design of high-speed data acquisition system based on band-pass sampling was presented and applied to the signal processing of wideband receiver. The Virtex Series FPGA was used as the main platform to control the high-speed ADC08D1000 for completing data acquisition, transmission，storage and signal processing. High-speed First Input First Output(FIFOs) were selected as the storage devices to implement data rate conversion. The system realized the software and hardware design，and test results verified the feasibility of the solution.

Abstract:

The corresponding solutions are proposed to tackle with the disadvantages of conventional oilfield Geographic Information System(GIS), including inconvenience of Client/Server(C/S) mode operation and maintenance, being unable to perform real-time online Point of Interest(POI) rendering, being incapable of segmentation and location according to regions, etc. An oilfield information query system of Browser/Serve(B/S) framework based on AJAX+JSON+HTML5 is designed and implemented. Experimental results show that the POI real-time rendering and regional segmentation improve on their interactivities, and the experiences of users are enriched, which meets the actual requirements of oilfield development. This work has paved the way for the development of diversified network services.

Abstract:

A detector can achieve quick response when it is much smaller than the wavelength of the source signal in THz wave band at the expense of signal coupling capability．Therefore, an antenna is applied to collect signals in order to enhance the signal coupling capability of the detector．The properties of antenna determine the frequency response band，the sensitivity and other parameters of the detector directly. A planar-integrated antenna is adopted for signal acquisition in the Nb5N6 microbolometer detector, which is fabricated by lithography，lift-off and other processes of micro-fabrication. The Nb5N6 microbolometer is placed in the center of the planar antenna. Aiming for the center frequency of 0.32 THz, a special capacitive coupling design is proposed to improve the signal coupling capability．

Abstract:

A double gate setting with priority of Doppler velocity and the Extended Kalman Filter(EKF) based Multiple Hypothesis Tracking(MHT) algorithm are proposed in order to realize Multiple Targets Tracking(MTT) in High Frequency(HF) ground-wave radar, and to effectively improve the performance of MTT by using the Doppler measurement. In the EKF based MHT, parameters obtained in the EKF are adopted directly to calculate the probability of each hypothesis. A simulation scene is built, and the EKF based MHT algorithm is compared with the one which assumes that the Doppler measurement is independent from the radius measurement. Simulation results show that the double gate setting helps induce number of clutter, and the EKF-based MHT algorithm is better than the other one under dense environments of HF ground-wave radar with stronger track-catching and false-alarm-filtering ability and higher efficiency.

Abstract:

The single-channel blind separation of GMSK(Gaussian Minimum Shift Keying) mixing signals is researched. The GMSK mixing signals can not be separated by the Per-Survivor Processing (PSP) algorithm directly, therefore, linear approximation processing of the GMSK signal is considered, which enables GMSK signal to be separated by the PSP algorithm. This algorithm separates the GMSK mixing signals by maximum likelihood estimation in the joint space of the symbol sequential and the channel parameters, reserves the best path and outputs the symbol pairs to get the separated signals. Simulation results show that the bit error rate performance produced by the PSP algorithm on separating the GMSK mixing signals is slightly better than that produced by the particle filtering algorithm; and the complexity of the proposed PSP algorithm is much smaller.

Abstract:

A new usage of Hough Transform is introduced in this paper.Firstly,the position and scope of the license plate is located and the image that contains the license plate is picked up.Then, a two-stage Hough transform algorithm is applied to the image to cal

Abstract:

A forward secure strong proxy signature scheme is proposed on the basis of the proxy signature schemes and forward secure schemes.The security of the proposed scheme relies on the difficulty of solving discrete logarithm problems and the difficulty of com

Abstract:

Based on three generally accepted basic hypotheses, the definition of environmental factor and restricting conditions of constant failure mechanism are discussed.The research status and common study methods of environmental factor are reviewed. Finally, a

Abstract:

For completing the scheme of hard target smart fuze, several factors influencing the outputting acceleration of the high-G accelerometer such as target material, impact angle, impact velocity, the fixed position of accelerometer, carry plane etc., are put

Abstract:

Blind source separation (BSS) is a recently developed methodology used to separate unknown source signals from their mixtures. It has been applied to many fields widely and effectively. The theory and two types of implementation methods-independent compon