Abstract:

Terahertz communication has become a current research hotspot due to its extremely large bandwidth, and further improving the system capacity in terahertz systems has also become a problem worth exploring. This paper optimizes the terahertz system composed of all-electronic components using a hybrid Probability and Geometric Shaping(PGS) scheme. The Pairwise Optimization(PO) algorithm is employed to adjust the Probabilistically Shaped 16-ary Quadrature Amplitude Modulation(PS-16QAM) signal after probabilistic shaping to obtain the desired hybrid PGS-16QAM signal. By testing the optimization effects of PS-16QAM, Geometric Shaping(GS)-16QAM and PGS-16QAM on uniform 16QAM at different net rates, it is verified that the hybrid shaping has the best optimization effect. When the wireless transmission distance is set to 2 meters and the Normalized Generalized Mutual Information(NGMI) experimets have shown that threshold is set to 0.92, PGS-16QAM achieves a net transmission rate increase of 15.6%, 11.8%, and 3.8% compared to traditional 16QAM, PS-16QAM, and GS-16QAM, respectively.

Abstract:

The demand for high-capacity, anti-interference, safe and reliable transmission between ships on the sea and between ships and aircraft is becoming urgent. Terahertz band has a high frequency band and large bandwidth, making it an excellent means of high-capacity transmission and anti-interference communication. Based on the characteristics of marine terahertz communication, the influence of water vapor attenuation on terahertz wave on the sea surface in China is analyzed firstly. Then, based on the link budget and propagation reliability calculation, a marine terahertz communication system is designed. After being tested on a 150 m river, the system's feasibility is verified by achieving a speed of 520 Mbps with an bit error rate of 2×10^-8.

Abstract:

In order to meet the requirement of increasing transmission rate, the future communication technology will naturally develop to a higher carrier frequency, and terahertz communication technology becomes a possibility. Aiming at the I/Q imbalance problem in terahertz communication system under the background of large bandwidth, an I/Q imbalance damage model is constructed under terahertz zero-intermediate frequency architecture. The algorithm derivation and compensation architecture design are completed in corresponding narrowband and broadband scenarios, and the algorithm performance is improved by improving the cost function for broadband scenarios. The simulation results show that the Mean-Square Error(MSE) of the proposed algorithm is improved by 15 dB compared with that of the statistical algorithm. In the experiment of 220 GHz zero intermediate frequency communication system, the MSE of narrowband algorithm proposed in this paper is improved by 7 dB, and that of the broadband algorithm is improved by 1 dB.

Abstract:

Traditional terahertz frequency doublers often utilize hybrid integrated circuits as implementation methods, leading to issues such as large size, high packaging loss, and poor stability. By employing an active device based on indium phosphide(InP) High Electron Mobility Transistors(HEMT) with a gate length of 2×25 μm, a fully monolithic integrated D-band frequency doubler is designed by using a combined simulation analysis method of Advanced Design System(ADS) and electromagnetic(EM) simulation. The frequency doubler is designed in the form of frequency doubling plus amplification, with the first stage being a frequency doubling circuit and the second stage using an amplification circuit. Within the range of 132~154 GHz, when the input power is 4.5 dBm, the output power is greater than 6 dBm, the fundamental wave suppression ratio is better than 31 dBc, the third harmonic suppression ratio is better than 36 dBc, and the maximum output power is 9 dBm@144 GHz, with a corresponding frequency conversion gain of 4.5 dB. The chip area of this frequency doubler is approximately 3.1 mm×1.3 mm. This design provides a new option for fully monolithic integrated terahertz sources and the realization of miniaturized terahertz sources.

Abstract:

Terahertz waves occupy a unique position in the electromagnetic spectrum, characterized by high frequency, high bandwidth, and high penetration, which hold broad application prospects in fields such as communication, radar, imaging, sensing, and security inspection. Frequency converters like frequency multipliers and mixers are key components of solid-state terahertz systems. Schottky diodes boast low parasitic parameters, simple fabrication processes, and ease of integration, with their operating frequencies covering the entire terahertz band. Frequency conversion devices based on Schottky diodes, featuring room-temperature operation, broad bandwidth, electronic tunability, low phase noise, and high sensitivity, have become the mainstream devices in terahertz transceiver links. This article reviews the recent developments in Schottky diode technology, including its structure and fabrication methods. Additionally, it introduces the current state of frequency multipliers and mixers based on Schottky diodes and discusses future development trends.

Abstract:

Terahertz communication is one of the important development directions for wireless mobile communication in the 6G era, characterized by large bandwidth and low latency, suitable for various application scenarios such as high-speed wireless backhaul and satellite communication. This paper designs a D-band (110~170 GHz) wireless communication system based on intermediate frequency synthesis, achieving D-band broadband wireless communication with a total bandwidth of (n×2) GHz by synthesizing n intermediate frequencies with a bandwidth of 2 GHz each, thereby achieving a transmission rate of over 100 Gbps. To verify the feasibility of the system, a 1/n scale-down verification was conducted on the designed n-path communication system. The results show that using a 2 GHz D-band channel bandwidth, a maximum of 11.2 Gbps air interface transmission rate and 9.4 Gbps service transmission rate can be achieved with 128-QAM(Quadrature Amplitude Modulation), proving that the n-path intermediate frequency synthesis system architecture using only one set of D-band RF front ends can achieve low-cost D-band broadband high-speed wireless communication.

Abstract:

Pulse Current Injection(PCI) is an important means of studying the High-altitude Electromagnetic Pulse(HEMP) effects on electronic equipment. This paper designs a shortwave antenna port contact pulse current injection experimental platform, studies the effects of two different working states (receiving and transmitting) of shortwave equipment, as well as the impact of three different working frequencies (low, medium, and high) on the injected current. It also explores the performance differences of antenna port protectors in both stand-alone and online states, providing a reliable basis for subsequent performance tests of shortwave antenna port resistance to electromagnetic pulse interference.

Abstract:

To address the issues of feed perturbation and reflector surface deformation in large radio telescope antennas caused by gravity, wind, and solar radiation, phased array feed technology is employed. By appropriately exciting each unit, the amplitude and phase errors resulting from feed perturbation and reflector surface deformation are compensated for. The performance of Gaussian feeds and phased array feeds under three different conditions is compared, and simulation results indicate that phased array feeds can not only correct the pointing deviation caused by feed perturbation but also compensate for the phase errors caused by reflector deformation, thereby enhancing the performance of the beam. Phased array feeds convert traditional mechanical surface adjustments to electronic surface compensation, which not only improves the performance of the antenna but also reduces resource consumption, making them suitable for large radio telescope antennas.

Abstract:

A broadband two-dimensional scanning triangular grid multi-polarization transmission array has been designed, with the array antenna adopting a dual-polarized all-metal Vivaldi structure. The miniaturization of the metal Vivaldi antenna can meet the array conditions of the triangular grid. Based on the theory of polarization formation, the characteristics of its multi-polarization formation are studied to adapt to more diversified applications. The prototype measurement results indicate that the antenna array can achieve high-power multi-polarization formation within the X and Ku frequency bands (operating bandwidth ratio of 3:1); with an active Voltage Standing Wave Ratio(VSWR) less than 3, the azimuth and elevation scanning angles can reach ±30°; the equivalent radiated power (within ±30° scanning angle) can reach 110 kW; the array profile is 17 mm.

Abstract:

Electrical Capacitance Tomography(ECT) image reconstruction algorithms utilize the sensitivity matrix as prior knowledge to invert the distribution of media within the pipeline, hence, the sensitivity matrix plays a crucial role in the quality of image reconstruction. Due to the soft-field characteristics of ECT sensors, the sensitivity distribution within the field is not uniform, with significant differences between the central and peripheral areas of the sensor, affecting the quality of the reconstructed images. This paper proposes a sensitivity preprocessing method based on the Sigmoid function. Simulation experimental results show that this method can significantly improve the uniformity of the sensitivity matrix and greatly enhance the quality of the reconstructed images: the Image Spatial Error(ISE) is reduced by 0.3825; the Relative Error(RE) is reduced by 0.386 5; and the Correlation Coefficient(CC) is increased by 0.0608, validating the feasibility of this method in ECT image reconstruction.

Abstract:

In response to the need for target highlighting in infrared night vision aiming systems, a method for extracting target contours from infrared images is proposed. This method is based on real-time infrared imaging systems, and after analyzing the characteristics of infrared target images, the shortcomings of the application of Sobel operator in infrared images are improved through operations such as Gaussian filtering pre-processing, contrast enhancement, and dark background edge removal. The simulation has achieved accurate extraction of target edges in infrared images. The application effect of the algorithm in the infrared night vision aiming system is verified on a Field-Programmable Gate Array(FPGA) real-time processing platform. The results show that the method for extracting target contours in the infrared night vision aiming system has good edge extraction effects in the FPGA real-time system and has achieved significant target highlighting performance with less than 2% hardware resource occupation.

Abstract:

The multi-level threats attribution in conventional Internet of Things(IoT) environments is mainly achieved through the classification of network data relationships, which overlooks the similarity between conventional data and threat data, leading to a large number of false positives in the attribution results. In response to this, a multi-level threats attribution method for IoT environments based on deep learning and genetic algorithms is proposed. A deep learning neural network is established to identify threat data in the IoT environment, and batch normalization operations are added to separate conventional data from threat data, extracting features of multi-level threats data. Genetic algorithms are applied to obtain the optimal individual, achieving the initial node attribution and positioning of threat data. Experimental results show that the attribution results obtained using the proposed method have fewer false positives and are more accurate, meeting the practical needs for the security maintenance of IoT environments.

Abstract:

In response to the current issue of low accuracy in sentiment polarity analysis of short texts in power consulting, this paper proposes an improved Latent Dirichlet Allocation (LDA) algorithm-based classification algorithm for power user consulting texts. Based on the analysis of the relationship between power consulting short texts and sentiment, concepts such as sentiment word co-occurrence bags, topic-specific words, and topic relationship words are defined. To improve the quality of semantic analysis, an execution process for the improved LDA algorithm for classifying power user consulting texts is designed. Experiments show that the proposed model demonstrates excellent performance, with an average precision of 90.91% and an average recall rate of 85.03%. The proposed model can fully leverage the advantages of multi-model integration, effectively enhancing the model performance.

Abstract:

To address issues such as congestion, latency, high packet loss, and low throughput in the data transmission of electricity information acquisition terminals, and to improve cache utilization and data transmission efficiency, a dual-queue cache optimization algorithm for electricity information acquisition terminals based on time series is proposed. Preliminary statistics are conducted on the time series information of user electricity consumption, and electricity consumption trends and anomaly detection results are extracted as upload data. A Dual-Buffer Queue Management based on Priority(DBQM-P) dual-cache optimization algorithm is constructed, which divides queues according to the priority of different services and calculates the optimal discard probability. Different packet discard strategies are implemented in the dual-queue cache model to achieve efficient transmission of electricity information acquisition terminal data. Experiments show that this method can collect user time series information, cache data according to the priority of services, and upload it to the electricity information acquisition system background for display, significantly improving the cache utilization of electricity information acquisition terminals, increasing the amount of data transmitted per unit of time, with the highest packet loss rate being only 0.58%, reducing data loss, ensuring the transmission of urgent and important business information, and enhancing the real-time and reliability of data transmission.

Abstract:

To investigate the issue of reduced electron multiplication factor in Complementary Metal Oxide Semiconductor(CMOS) image sensors with an aluminum oxide passivation layer structure after being bombarded with high current density electrons, this paper simulates the fabrication process of CMOS image sensors with an aluminum oxide passivation layer. An aluminum oxide passivation layer is prepared on the surface of P-type silicon with a crystal orientation of (100) and a doping concentration of 5×10¹⁸ cm^-3. The conditions for electron beam bombardment of CMOS image sensors are simulated, and the prepared P-type silicon samples are bombarded. A high-frequency C-U testing device is employed to test the high-frequency C-U curves of the samples before and after bombardment. Based on the test data and analysis using the Shockley-Read-Hall(SRH) theory and minority carrier transport equations, it is concluded that the internal positive charge deposition in the passivation layer and the increase in defect state density at the silicon interface caused by electron bombardment are the intrinsic reasons for the reduction in the electron multiplication factor of this type of image sensor.

Abstract:

The confusion characteristic of masking technology can increase the difficulty of attackers to analyze the logic value of the circuit, and the combination of masking technology and Dual-Rail Precharge(DRP) technology can further play a role in resisting power analysis attacks. The application of masking technology and dual-rail precharge technology requires corresponding processing of the input signals and output signals. Based on this, this paper proposes a single rail to dual-rail conversion logic circuit, which can realize the conversion of signal. Then a mask logic conversion circuit is proposed, which can realize the conversion of the output value of the circuit according to the mask value. At last, a single-dual rail mask logic structure is proposed to form a circuit design scheme with power attack resistance. The above logic circuits have been verified by Hspice simulation and have correct logic functions, which provides a way for the circuit design against power analysis attacks.

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:

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:

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:

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 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 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 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