Editor in chief:Prof. Sun Shenghe
Inauguration:1980
ISSN:1002-7300
CN:11-2175/TN
Domestic postal code:2-369
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Zhao Xindan , Zhang Xiaodong , Hou Chenggang , Niu Hang
2017, 40(10):1-7.
Abstract:In order to solve the shortcomings of the existing demodulation system, which can not guarantee the cycle integrity of the driving voltage, a wavelength demodulation system based on realtime reference light path and the tunable FP cavity filter is proposed in this paper. The hardware signal conditioning circuit consists of twostage amplifier circuit and secondorder lowpass filter circuit, which is high signal to noise ratio and low cost; The software analysis and processing module consists of highprecision computer program, which is realtime data acquisition, processing and preservation. What’s more, a sampling point compensation algorithm which is proposed, which can make host copputer produce complete periodic voltage under any circumstance. The experimental results show: the maximum measurement error of the demodulation system is 34 pm, the measurement range is 40 nm, and the maximum tuning speed is 100 Hz. This system can satisfy the requirements of engineering practice.
Dai Zhilan , Ye Yufeng , Qin Xiaofei
2017, 40(10):8-11.
Abstract:As a kind of high power type energy storage device, super capacitor has been widely used in life. However, due to the low voltage of the capacitor, the super capacitor bank must be formed by seriesparallel connection in the actual energy storage system. Aiming at the problem of voltage unbalance in the series connection of supercapacitors, an improved capacitor voltage control circuit is proposed in this paper. The circuit consists of capacitors and switches and transformers, through the feedback control, simplified parameter calculation, improve the voltage uniformity. Finally, MATLAB/Simulink simulation results show that the voltage balance is fast, the error is small, and it is easy to expand under the control circuit. It has a high value in the application of capacitor energy storage system.
Liu Jian , Chen Xuan , Wang Wenjiang
2017, 40(10):12-16.
Abstract:SRM is a multivariable, nonlinear and strong coupling system because of its special structure and magnetic circuit saturation, the flux linkage, current, torque and rotor angle has a complex nonlinear relationship. As a kind of efficient strategy for dealing with nonlinear system control, the Backstepping Control method is efficient and robust. In this paper, threephase 6/4 SRM is selected to research, according to SRM formula to design the backstrpping control model, using Lyapunov stability theory and proves its stability, proposed SRM current chopping control based on backstepping method, through MATLAB/simulink simulation, the simulation results show that when the motor is started, the current fluctuation in the 80 A up and down, forming a flat top wave, it is proved that the proposed method is reasonable, and provides another idea for the design of the actual SRM current chopping control system.
Wang Guodong , Ji Huiqiang , Qiao Zhenpeng
2017, 40(10):17-20.
Abstract:In order to analyze the effect between output power and coil turns of the four coils model of magnetic resonant coupling wireless power transmission system, in this paper, the system model was established and the output power formula was calculated using the circuit theory. The output power curve of system was analyzed through the MATLAB software simulation. The result shows that the increase of the receiving coil turns make the system output more power than the increase of the transmitter coil turns when the four coils have the same structure and material. Meanwhile, the increase of receiving coil turns make the system frequency have obvious drop when the system reach maximum output power, and the frequency variation is not obvious when the increase of transmitter coil turns. The result also shows that when the receiving coil turns increase the peak load resistance of output power is also increasing. So when the four coils have same structure, the increase receiving coil turns can improve the output power.
Du Enwu , Yang Yuyan , Jiang Jian , Xu Yi
2017, 40(10):21-25.
Abstract:AS site environment of the shock parameters test was quite poor. A high performance trigger controller based on FPGA is designed to improve the reliability and stability. Based on the independent components and FPGA, two sets of trigger controllers are designed. And parameters are designed according to the testing requirements of explosion. The advantages including stability and reliability which brought by using FPGA are analyzed. The results show that the synchronization time of the trigger controller based on FPGA is less than 50ns under the condition of extreme temperature, and the error trigger rate is 0, which has higher stability and reliability.
Wang Xiarong , Zhao Haiwu , Wang Guozhong , Fan Tao
2017, 40(10):26-30.
Abstract:This paper designs and implements a living video system based on DSS. Firstly, the software core architecture of DSS server is analyzed. In view of the network congestion and packet loss caused by UDP transmission in living video system, the congestion control scheme based on RTCP feedback is adopted, After the system test shows that the average delay when living is about 100 ms, and the overall test picture is smooth, effectively reduce the network congestion and packet loss; and CPU occupancy rate test shows that with the increase in user CPU occupancy rate is not presented obviously increase, singleuser CPU occupancy rate stabilized between 1% to 3%, 20 users CPU occupancy rate stabilized between 6% to 9%, indicating that the system concurrent processing performance is better. The overall system has a good performance, to meet the practical application needs.
Zhao Qiding , Wang Guozhong , Fan Tao
2017, 40(10):31-36.
Abstract:With the continuous development of digital television transmission technology and the rapid popularization of intelligent terminals, the form of digital television tends to be diversified. Considering the advantages and disadvantages of traditional IP network television, cable television and radio television and in order to overcome the shortcomings of traditional TV transmission system, the use of IP network transmission mode ,this paper designed and realized a multiscreen interactive system based on terrestrial digital broadcasting television (DTMB). Through the combination of terrestrial broadcasting network and broadband IP network, the terrestrial digital TV signal through IP network multicast transmission to the intelligent terminal equipment, can effectively reduce the consumption of network resources, while ensuring that multiple intelligent devices at the same time watch TV programs. Firstly, introduced the system hardware block diagram and the main chip that the system involved in. Then, described the design of demodulation software, the realization of IP over TS and the design flow of client software in detail. Finally, summarized the application scene of the system.
Zhang Gan , Shi Huoquan , Zou Jiafeng
2017, 40(10):37-41.
Abstract:In order to get the harmonic current in the power system quickly and accurately, an improved harmonic current detection algorithm is proposed in this paper based on the traditional ipiq harmonic current detection algorithm. The improved method proposed in this paper is taking the load side of the threephase voltage through the Clark transformation and Park transformation to produce synchronous spin signal to complete the common phaselocked loop structure of the phase detector function, resulting in phase difference signal Δθ, and then through the PI controller adjustment and integration link to get Aphase base wave electrical angle, and then through the positive and cosine signal generator to produce standard positive and cosine signals to reduce the error caused by voltage distortion;the highpass filter is used instead of the lowpass filter in the traditional algorithm to obtain the threephase harmonic current directly, which simplifies the system structure, reduces the delay and improves the real time performance of the system. Simulink simulation results show that the method can detect the harmonic current more accurately and quickly, and improve the realtime performance of harmonic detection.
Yu Yingjie , Yang Xuexia , Lou Tian , Qiu Houtong
2017, 40(10):42-46.
Abstract:This paper presents a broadband continuous transverse stub (CTS) antenna array with wide scanning range based on substrate integrated waveguide (SIW). The SIWCTSs radiators are periodically arranged on the coplanar waveguide (CPW). A novel broadband CPW slowwave structure is proposed as the feedline to increase the phase difference of the adjacent antenna elements. Depending the phase variation from 89.3° to -83.3° within the frequency range of 8.6~13.7 GHz, a wide beam steering range depending on frequency is achieved. A reflector is located at onefourth wavelength away from the antenna array to reduce the backward radiation. A 4element CPWCTS antenna array based on SIW is designed and simulated using the HFSS fullwave analysis software. The simulated results show that the frequency range of the reflection coefficient less than -10 dB is 8.6~14 GHz. The main beam of the antenna is scanned from -40° to 56° in Eplane with the frequency increasing. At every main radiation direction, the gain varies within the range of 9.8 ~ 12.3 dBi.
Xue Shaofan , Qin Gang , Chen Zhongxiao , Rong Mengjie , Feng Li
2017, 40(10):47-51.
Abstract:In view of the swing of the suspension transportation device, the bridge crane is taken as the research object. The mathematical model of crane load swing is established by using Lagrange equation, and the control scheme of the motor is established by using the attitude sensor to collect the realtime swing information of the crane. According to the function requirements of the system, the hardware circuit of the system is designed with the MC9S12XS128 chip as the core, and then the computer software is programmed with Kalman filter and complementary filtering algorithm. Finally, the closedloop control method of angle feedback is adopted to realize the anti swing control of the suspension by the drive of the frequency converter. The experimental results show that the design of the suspension anti swing control device has good control performance, so that the motor can be removed quickly after the motor stops running. The utility model has the advantages of strong adaptability, high safety and high efficiency.
Lu Chengqiang , Li Qianzhen , Wang Changxu
2017, 40(10):52-55.
Abstract:For the automatic discrimination of checking the quality of physical index of college students, a design scheme of intelligent physical measuring instrument is proposed. Firstly, using STM32F103 microcontroller as the main controller, campus card numbers are displayed on the TFTLCD screen after swiping card by radio frequency module. Secondly, weight, height and vital capacity are measured by weighing sensors, ultrasonic sensors and vital capacity sensors. Thirdly, the physical data in the form of text messages is sent to the designated mobile phone by GSM module. In addition, the function of data wireless transmission can be achieved by using bluetooth module. Manmachine interaction is realized through the TFTLCD screen and bluetooth mobile phone client. Finally, the experiment demonstrates that the system runs extremely smoothly, realizes the diversitied function and to further strengthen that more attention should be paid to physical health of college students.
2017, 40(10):56-60.
Abstract:Thermal problems due to the high current density of printed circuit boards (PCB)is one of the important problems that PI (power integrity) engineers focus on. With the rapid development of integration, the current density of PCB is sharp increases also, especially the power module with a large current is easy to happen overheating as the circuit board with high current density, and thus have a negative impact to the circuit performance. An accurate description of the relationship between the temperature rise and the current density of the complex PCB is an important problem that the PI engineer must properly solve. In this paper, we will firstly discuss how to accurately measure and evaluate the temperature rise caused by the current density on PCB,and then use it to guide the PCB design and find the current density and thermal problems existed in the PCB.
Tang Yongcong , Liu Tao , Geng Qiang
2017, 40(10):61-65.
Abstract:In this paper, a fiveleg inverter is proposed as a control object, and a cooperative control strategy based on model predictive control strategy is proposed. Compared with the traditional algorithm, the new algorithm adds torque synchronization Strategy to ensure the output power balance of the two motors, while the crosscoupling control thinking into the fiveleg two motor control system speed outer loop controller to improve the two motors do not match the parameters of the speed synchronization performance. Simulation results show that the new algorithm can effectively improve the synchronization performance of the motor speed and torque of the two motor systems under the precondition of keeping the torque control speed of the model predictive control algorithm higher than the traditional control strategy, and has certain application value.
Yang Rui , Yan Jun , Ni Qingrong
2017, 40(10):66-69.
Abstract:With the upgrading of China′s energy structure, natural gas is more and more popular with people. The technology and equipments related to natural gas are also experience a new round of innovation. The intelligent wireless gas meter this article mentioned is the product of technological innovation. When such intelligent instruments are in the process of largescale use, it is necessary to ensure the quality of the instrument used. So it’s important to carry out the verification work efficiently and accurately on such intelligent instrument, the article is to solve this problem. Based on the advantages of B/S, C/S modes and business characteristics, this paper proposes a new instrument test system which is flexible,efficient,stable and accurate.This paper will discuss the whole construction andpartial modules, and finally verify the conclusion through the system test.
2017, 40(10):70-74.
Abstract:Based on the gyro free strapdown inertial attitude measurement principle of missile system is analyzed. From the point of view of engineering installation, this paper puts forward a kind of simple installation method of the nine accelerometer which can realize the gyro free strapdown inertial navigation system. The simplicity and rationality of the nine accelerometer configuration scheme are analyzed. The calculation principle of the guiding principle of installation of the nine acceleration are deduced based on the detailed calculation of the algorithm of GFSINS, which proves the feasibility of the nine accelerometer configuration. Finally, the mathematical model of angular acceleration and linear acceleration is established. On the assumption that there is no random white noise and constant error,through the MATLAB simulation, the angular velocity and angular velocity error of the system are given ,and it is proved that the configuration of the nine accelerometer is simple and feasible.
2017, 40(10):75-79.
Abstract:Under ideal conditions, the LFMCW radar difference frequency signal is a standard sinusoidal signal in the regular region, but a large number of measured signals show that the difference frequency signal contains complex noise signals, which seriously affects the ranging accuracy. The use of analog filters is the most direct way to filter out these noise signals. Aiming at the characteristics of the frequency band of LFMCW radar is similar to the noise band, a simple design method of simulated elliptic filter is introduced. The elliptic function low pass and high pass filter are designed respectively, and then the cascade method is used to form a band pass filter. Experimental results show that the proposed bandpass filter can effectively reduce the noise interference and improve the quality of LFMCW radar frequency difference signal.
Shangguan Xuanfeng , Wang Yachen
2017, 40(10):80-85.
Abstract:In order to satisfy the low speed requirement of wind power generation system, two different types of axial flux permanent magnet machines were designed in this paper. The paper analyzed the different characteristics of these two kinds of topological structure, the shape of the permanent magnet poles and polearc coefficients were determined, the generators of slotpole coordination problem was discussed, and the parameters of the permanent magnets and windings were calculated in detail in this paper. The paper computed the models with the quasi3D finite element analysis (FEA) methodology for both generators, the reliability of designed methodology applied in axial flux permanent magnet machine was proved by finite element analysis (FEA) results. At last, the electromagnetic characteristics of these two types of generators were compared by Finite Element Analysis (FEA) results.
Dai Haibin , Wang Tao , Zhang Jinyi
2017, 40(10):86-91.
Abstract:To meet the design requirements of the miniaturization and circular polarization of ultra high frequency(UHF) band radio frequency identification(RFID) reader, a novel compact square quadrifilar spiral antenna with righthand circular polarization is presented. The antenna is composed of four invertedF elements printed on the FR4 substrate, and the dimension of the antenna can be effectively reduced by array element bending and the continuous phase rotation method. The improved microstrip powerdivided feeding network and a new coupling match method are used to improve the bandwidth of the axial ratio and gain of the circularly polarized antenna. The proposed antenna has a size of 56 mm×56 mm×8 mm than the reference design reduced by 12.9% to 86%, the 3 dB beamwidth of more than 120°, the peak gain of 2.8 dBic with the axial ratio under 2 dB and the cross polarization of less than -15 dB.
Jiang Longwei , Zhao Guangxing , Zhao Mingbo , Zhong Ming , Wang Qi
2017, 40(10):92-98.
Abstract:A design and implement method is studied based on the advantages of virtual cockpit system flight simulator. Combining entity cockpit composition structure and layout, the function requirement and performance requirement of virtual cockpit system are clear. Elaborating the basic design principle of the graphical instrument and control panel, the way of combining GL Studio with VC++ is adopted to simulation development. In view of the cockpit system’s complex structure and various modules, the idea of modularization is used. Classifying the simulation module from the top, avoids the complex redundant structure, reduces the coupling between the modules and makes the system easy to maintain, use, and to upgrade. The virtual cockpit system design method largely reduces the cost of system development and it improves the speed of development. It will be a great positive role to promote the pilot′s basic flying skills and tactics level.
Lei Anqi , Feng Yutian , Tang Zicheng
2017, 40(10):99-103.
Abstract:In human computer interaction, the interaction between humanhands and machine is the most common way, so gesture interaction research is one of the focuses of humancomputer interaction research today. Based on Leap Motion, this paper studies the threedimensional space object detection and tracking, and proposes a new algorithmLBFGSEKF algorithm. The algorithm is based on the EKF method proposed by reducing noise, through the method of the LBFGS algorithm is used to replace the Hessian matrix in each iteration instead of the EKF algorithm, which consumes memory and reduces the computational rate, resulting in poor realtime, thus forming a new target tracking algorithm. The simulation results show that by this new algorithm LBFGSEKF for gesture recognition, the error can be reduced and the realtime performance of target tracking can be improved.
Yang Guangchao , ang Jianming , Wu Guangxin
2017, 40(10):104-108.
Abstract:Aiming at the problem of complex electromagnetic environment and interference between different devices in largescale ship platform, the technology of RF interference cancellation is studied. The mathematical principle and system model of RF interference cancellation are analyzed, and the relationship between cancellation performance and amplitude error and phase error is analyzed. By analyzing the principle of adaptive filter and combining the characteristics of Xband radar of large ship platform, a kind of radio frequency interference cancellation technology is proposed. The scheme uses the least mean square error (LMS) algorithm to verify the feasibility of the cancellation scheme. The simulation results show that the cancellation ratio of the RF cancellation system can be up to about 40 db, and the high cancellation ratio can be achieved.
2017, 40(10):109-112.
Abstract:The main objective of this article is to improve the performance of SDWTPMUSIC algorithm to SDWPPMUSIC algorithm.Then,we compare its performancem with 3 famous eigen structurealgorithms, known as the multiple signal classification (MUSIC), the estimation of signal parameter via rotational invariance techniques (ESPRIT), and nonsubspace method maximumlikelihood estimation(MLE) for direction of arrival (DOA).The performance of this DOA estimation algorithm is based on uniform linear array (ULA). A number of simulation results were carried out using MATLAB and werecompared with experimental ones. The comparison shows that the MUSIC algorithm is more accurate andstable compared to the ESPRIT,MLE and SDWPPMUSCI algorithms.
Wang Hong , Lin Zijian , Wang Lingling
2017, 40(10):113-117.
Abstract:For the characteristics of three degree of freedom helicopter, such as multivariable, strong coupling and so on, first the mathematical model of the system was established from three channels individually. These three channels were evaluation channel, traverse channel and rotation channel. Then for evaluation channel, PD controller was designed; while for coupling traverse channel and rotation channel, a kind of method was adopted which making traverse angle as inner loop, then PID controller was designed for inner loop and outer loop individually. Considering the factor about uncertain parameters in system, and common PID controller could not suit the factor about varying parameters, thus fuzzy controller was designed. It was shown by simulation that fuzzy PID could overcome the deficiencies in common PID, and got better control effect.
2017, 40(10):118-121.
Abstract:In order to improve isolation degree of disturbance, a new ADRC based on NLE_PDFF feedback was proposed. Firstly, Mathematical model for precision analysis was formulated to evaluate the performance of the presented approach. And then, the NLE_PDFF_ADRC controller was designed. Finally, An experiment was performed to test the disturbance rejection of the NLE_PDFF_ADRC controller when the speed disturbance was from 3 to 5 Hz as compared with the traditional square PI compensation method. The results show that NLE_PDFF_ADRC can reduce the disturbance error 30%. The algorithm has been successfully applied to a stabilized platform.
Tan Lifang , Liu Rong , Huang Gang , Zhang Xiong
2017, 40(10):122-126.
Abstract:Aiming at the problem of high feature dimension and low recognition rate in speech emotion recognition, In this paper, we propose a genetic algorithm for feature dimension reduction and construct a multilayer SVM classifier based on binary tree structure for the recognition of speech emotion. First, the common emotional features are extracted after preprocessing the speech signal. As there are many features and redundant data, the genetic algorithm is used to optimize the extracted features. Then, the hierarchical SVM classification model of the binary tree structure is trained by using the most discriminative features. The experimental results demonstrate the effectiveness of the proposed speech emotion recognition scheme on the Berlin emotion corpus containing 7 emotions.
Lu Yating , Ling Xiaofeng , Wang Cong , Zhao Zewei , Jia Jie , Chen Shugeng
2017, 40(10):127-133.
Abstract:At present, assessment based on traditional scale and manual measure are the main methods for evaluation of hand function for stroke patient. However, due to the disadvantages of large errors, poor efficiency and discontinuous evaluation results, it’s difficult for these methods to meet rehabilitation needs. This paper presents a quantitative evaluation method of wrist extension based on multidimensional vision evaluation system, the system captures action parameter using optical motion capture device and computer vision technology, it can get the motion data of patient’s both hands through multidimensional vision acquisition and intelligent analysis and presents the analysis result. This paper introduces hardware and software structure of the system, data acquisition process and analysis of evaluation result in detail and the result is compared with the result of traditional scale and manual measurement. In this paper, we use the ‘wrist back’ as an example for experiment, the result can meet the requirements of clinical accuracy and can be more accurate and flexible. This method also can make up for the shortcomings of discontinuity and nonprecision.
2017, 40(10):134-138.
Abstract:The alignment of an image pair by means of transformation matrices is a challenging problem in computer vision, especially when the transformation is unavailable to compute and free of noise. In this paper, we first use the SIFT algorithm to detect the feature points, and then during the image alignment process, we propose to iterate the reference images and solve the transformation matrix under the least squares constraint. Experimental results on aligning some real images with few or none overlap regions show the proposed alignment algorithm outperforms the stateoftheart image alignment methods.
Li Jian , Zeng Dan , Zhang Zhijiang , Zhu Qinyi
2017, 40(10):139-142.
Abstract:In this paper, for the scene of panoramic driving recorder, we obtain a panoramic video using two video streamings taken by an opposite pair of fixed binocular fisheye cameras. We calibrate the parameters of fisheye camera and correct distorted images using a cylindrical mapping model of perspective projection. Then we extract the SIFT features for two frames of corrected image and remove mismatching points as well as figure out a homography matrix using the RANSAC algorithm. Finally, we use the linear weighted fusion method between the two frames of cylindrical image to get a panoramic image. In this experiment, we use cylindrical projection which is consistent with human visual characteristics. And comparing with perspective projection, cylindrical projection reserves more information of view which can help drivers to observe more important information.
Zhang Chiyu , Jia Yinliang , Liang Kangwu
2017, 40(10):143-147.
Abstract:In order to improve the visual effect of degraded images in foggy environment, a fast dehazing algorithm for single image is proposed based on the degradation model and the dark channel prior estimate. Using dark channel prior estimates the atmospheric transmittance roughly, then using edge preserving filtering estimates the refinement of transmittance, after that try to estimate the sky region in the original image for compensating of the transmission of the region. Finally, according to the estimated atmospheric light and transmissivity, the fog image can be recovered by the atmospheric degradation model. In order to solve the problem that the color of the image is darker, the adaptive histogram equalization method is used. The experimental results show that compared with the existing algorithms, the proposed algorithm can effectively improve the effect of image fogging and speed up the processing speed.
2017, 40(10):148-152.
Abstract:According to the problem of the strong background noise and edge blur in intravascular ultrasound(IVUS) images, an improved anisotropic diffusion is proposed. Firstly, median filter is imported to the PM algorithm, and then the gradient mode of the original image is replaced with the gradient mode from the image which is smoothed by the median filter to control the process of diffusion. Secondly, the direction of the conventional diffusion anisotropic diffusion equation is extended from 4 directions into 8 directions to retain more image details. Thirdly, a method of adaptive selection of the diffusion threshold K is put forward. The experimental results show that the improved algorithm has a satisfactory effect in removing noise and preserving edge, and providing a basis for the edge extraction of intravascular ultrasound images.
Li Pan , Zhou Rongjing , Zhang Jing
2017, 40(10):153-156.
Abstract:Because of the harsh environment of the scene of the accidents, the rescue workers are the only persons who are able to enter it. So the commanders outside are difficult to make the rescue plan timely. If the rescue workers use a wireless image detection system to transmit live video of the scene, the commanders could see the situation and quickly make the appropriate rescue plan. It not only effectively saves the rescue time but also greatly improves rescue capabilities. The system can transmit video signals over wireless network. Both transmitting and receiving devices have four channels to choose. Both receiving and display system are handheld or vehiclemounted, and they can be installed in the command car. The transmitting device is batterypowered. There are also optional lighting and temperature, humidity or smoke sensors, particularly, can be used for detection in smoke and dark environments.
2017, 40(10):157-160.
Abstract:With the rapid development of 4G network and the Internet, OTT video and live video outbreak rapidly, the mobile video business has gradually become the most important flow entry, so we need a series of indicators to measure video service performance over 4G mobile network. Current main method is based on the quality of service (QoS) and the quality of experience (QoE). QoS does not take into account users’ subjective opinion and fail to measure video quality and user experience effectively. The approach based on the QoE involves the user subjective factor while watching video and objective factor, which can reflect user mobile video experience effectively. This paper studies the influence of wireless parameters, video quality, playback quality and terminal parameters on the mobile video experience, establishes the mobile video experience evaluation model based on Analytic Hierarchy Process(AHP), and developed the video experience evaluation software VideoMos based on the ijkplayer video player framework and accuracy rate reached 71.57%, with a certain reference value.
Li Xujie , Chen Xing , Sun Ying , Li Chenming , Hua Siyang
2017, 40(10):161-165.
Abstract:DevicetoDevice(D2D) communications can effectively improve the network capacity. A capacity optimization method based on multipopulation genetic algorithm (MPGA) is proposed, which deals with the number of terminals that can be accommodated in D2D communications. As the traditional cellular network mobile terminals have interference on the D2D users, and the D2D terminals which reuse the same frequency introduce interference each other, it affects the number of accessible D2D terminals. The MPGA based scheme proposed in this paper can adjust the resource allocation scheme quickly, effectively reduce interference under the same frequency, and improve the number of terminals which can be accommodated in the network. The simulation results show that the resource allocation scheme based on MPGA can allocate the reasonable channel resources quickly to reduce the total interference in the system. Besides, it can also improve the number of accessible terminals and the network throughput simultaneously.
Liang Liyuan , Zhou Zhigang , Xu Chenhao
2017, 40(10):166-170.
Abstract:At present, the small commercial unmanned aerial vehicle data link is in the stage of rapid development, the world′s major countries are carrying out this area of work, and many Western powers have achieved technical results. However, the level of relevant research in China is still relatively backward, and no comprehensive commercial data link system has been established. Therefore, it is of great significance to carry out research on data link of small commercial unmanned aerial vehicles. In this paper, STM32 single chip and SI4463 chip, designed a wireless realtime data transceiver system. It is a UHF band based on the work distance of 10km, the data transmission rate of 10 Kbps UAV narrowband data link system, the system has a high transmission rate, data transceiver stable and reliable advantages
Peng Baotong , Ma Hong , Mao Xinfeng
2017, 40(10):171-175.
Abstract:With the extension of the deep space detection, the measurement of spacecraft is particularly important. The measurement of the distance between the spacecraft and the measuring station is an important part of the deep space detection. This paper is based on the characteristics of regenerative pseudo code ranging, and the paper introduces the development history of pseudocode ranging, analyzes the advantages of regenerative pseudocode ranging, discusses the development process and pattern selection of the distance code used in regenerative pseudocode ranging, and Tausworthe for two yards in the ranging accuracy and capture time were analyzed, then the speed rate acquisition and the code acquisition are also discussed. Finally, the existing problems in the reconstructed pseudocode ranging are described, and the next research work is pointed out.
He Wanxia , Xiao Zhongyin , Jiang Yifei
2017, 40(10):176-180.
Abstract:In this paper, a novel hexagonal CSRR (complementary splitring resonators) structure is proposed, and a SIW (substrate integrated waveguide) dualband filter is designed. By adjusting the size of the four sets of CSRR clamp ring, the two resonant frequencies can be controlled. The first passband and the second passband of the filter are respectively formed by a hexagonal CSRR clamp ring with different sizes of up and down two layers, and can control the position of the frequency points independently. This design uses four node topology, through the cross coupling to form the two transmission zeros, forming a high stopband suppression characteristics. The two frequency points of the filter are 2.4 GHz and 5.2 GHz, and the relative bandwidth is 8% and 5%, respectively. The utility model can be widely used in the RF receiver frontend system of the wireless communication field, and has the characteristics of miniaturization, low loss and easy processing.
Zhou Guangli , Sun Yanzan , Wu Yating , Wang Tao
2017, 40(10):181-187.
Abstract:This paper studies the optimization algorithm of power allocation in decodeandforward OFDM twohop relay links aiming to maximize the energy efficiency of the system. First, the circuit power consumption of the system is taken into account and modeled as a linear increasing function of the rate. Then, under the condition of satisfying the rate and bit error rate, the energy efficiency optimization objective function is established. Finally, based on convex optimization theory, the optimal modulation and power allocation of optimal energy efficiency are obtained. The simulation results show that the proposed power allocation algorithm can lead to the optimum energy efficiency.
Yao Siqi , Wu Shiyou , Zhang Jingwei , Ye Shengbo , Fang Guangyou
2017, 40(10):188-195.
Abstract:Obstacle detection technology based on ultrawideband life detection radar has broad application prospects in the field of noninvasive detection such as disaster relief and antiterrorism operations. At present, most of the researches at home and abroad are using single point of view radar to detect the target, and it is difficult to detect the position of the body in the condition of low SNR. In view of the limitation of the above methods, this paper uses the multiple observation points to put the radar, and the echo signal is detected by correlation, and the spatial position of the body is obtained. The simulation results show the superiority of the proposed method in low SNR conditions. The experimental results show that the proposed method is feasible and can detect the location of life.
2017, 40(10):196-199.
Abstract:In the wind speed (0~1 m/s) space flow field measurement, the sensor accuracy requirement is high, the realtime online instrument data accuracy is not enough, hysteresis of data acquisition; Consider using multiple sensors measurement improve accuracy, but also has the problem of data fusion. Velocity flow field measurement, the author of this paper, based on kmeansdata collection and pretreatment of RBF neural network soft measurement model, firstly, intermediate variable (current value), using the kmeans clustering, use RBF network training to get a single sensor data; Based on correlationsensor data fusion algorithm of kalman filtering, eliminate invalid data points, and get accurate fusion wind speed prediction. Measurement experiment and data results show that this method processing data results of hysteresis is small, processing speed, high precision of data.
Kang Lifu , Sun Jing , Wang Yun , Huang Hongbo , Wang Weilian
2017, 40(10):200-204.
Abstract:To design a portable heart sound collection and analysis device, and can locate the first heart sound (S1) and the second heart sound (S2).Measurement Studio was used as the development platform to realize the acquisition, storage and analysis of heart sounds of congenital heart patients. In this paper, the double threshold segmentation method is used to locate S1 and S2.The system better to complete the patient heart sound signal acquisition, storage, echo and playback function. The effect of sound filtering is obvious, and the envelope after filtering can locate S1 and S2 well. Through the system to complete the census of congenital heart disease, compared to the experts personally go to the remote mountain area onsite auscultation, more convenient and quick. For the future development of heart sound auscultation equipment to lay the foundation.
Chen Xiaomeng , Qin Yurong , Zhao Long , Chen Ni
2017, 40(10):205-210.
Abstract:Steadystate visual evoked potential (SSVEP) is widely used in brain interface and medical clinical diagnosis when the lock is locked and the signaltonoise ratio and transmission rate are higher. The interaction between auditory and visual stimuli has great influence on brain cognition and its application. Therefore, it is very meaningful to study the effect of auditory stimulation on SSVEP. At the frequency of 12 Hz, 20%, 30%, 40%, 50%, 60%, 70%, 80% and 95% of the light stimulation frequency, respectively, add 500, 1 000, 1 500Hz sine pure tone, loudness of 50 dB of auditory stimulation, the study of SSVEP changes in the law. The results showed that SSVEP showed a “window” effect with the change of duty cycle in the same subjects, and the effect of auditory stimulation on SSVEP was enhanced or inhibited. In addition, the position, number, and degree of enhancement or inhibition of the “window” of the auditory stimulus impact on SSVEP is also due to the fact that SSVEP is enhanced or inhibited. The results provide a meaningful experimental basis for better study of the mechanism of interaction between brain and brain signals produced by visual and auditory stimuli.
2017, 40(10):211-215.
Abstract:A co-prime compressive sampling scheme based on chaotic digital filter is proposed. Compressive measurement matrix that employing chaotic digital filter avoid the problem of hardware implementation of classical Gaussian random measurement matrix. It also reduce the complexity of subsampling hardware implementation, while ensuring the incoherence of sensing matrix. For further reduction of data to be processed, a coprime sampling method is devised for compressive sensing radar. Numerical results demonstrate that compressive radar system that using the proposed coprime chaotic compressive sampling scheme can detect target’s parameters accurately.
Ma Xinxin , Wang Shanhai , Liu Qian
2017, 40(10):216-220.
Abstract:For a long time, the weather modification operation information is collected and reported manually which is a very heavy work. In recent years, as the weather modification operational period grows the projectile consumption increases gradually. The requirements of the accuracy and the timeliness of the operation information collection are become higher. So the difficulty of the information collection and management is further increased. With the further application of acoustic technology in the meteorological industry, and the sound acquisition instrument development successful based on operation information automatic collection which make the operation information record and transmit automatically possible. So the data transmission and use of the ground artillery and rocket has become a new research direction of the weather modification. The Weather Modification Center of Henan Province has carried out ground artillery and rocket operation information automatic acquisition and application research by adding a fixed sound acquisition instrument in Xuchang City. By using the sound acquisition instrument and different ground operational equipments, it has achieved good results by the comprehensive utilization of the original information. So it provides a simple and effective solution for realtime automatic acquisition operation information.
Guo Chen , Fu Gaoyuan , Yang Maohui
2017, 40(10):221-225.
Abstract:Turbo code is a channel coding with excellent errorcorrecting performance in the condition of low noisesignal ratio. It attracts attention of many science researchers in that Turbo code has significant performance of only 0.7 dB difference from Shannon limit. Currently, the utilization of Turbo code in data transmission has become the standard of wireless transmission protocols. This paper focuses on Turbo code and its implementation with FPGAand analyzes the decoding theory and algorithm of Turbo code. Firstly, it analyzes the process and characteristics of encoding. Then it introduces the decoding process and the MaxLogMAP algorithm used in its decoding process. At last its ends up with the implementation of data transmission with fieldprogrammable gate array(FPGA) and achieved good results.
Wang Xingguang , Sun Yanzan , Wu Yating , Wang Tao
2017, 40(10):226-230.
Abstract:In experiments concerning electronics, communication and related engineering areas , researchers often need to measure and evaluate the power consumption of active devices. To meet this demand, this paper proposes a design of an efficient and automatic power measuring system based on MATLAB and builds the hardware and software platforms. The hardware consists of a computer and a programmable power supply, which communicate by a serial port. PC sends commands encapsulated by Modbus communication protocol to the programmable power supply, so as to realize control, monitoring and acquire the power supply’s output voltage and output current data that can be used to calculate the power of the active device. Experimental results demonstrate that this measurement system can measure the power of active devices, whose operation is quite convenient , stable, and efficient.
2017, 40(10):231-237.
Abstract:Temperature wireless monitoring system for multitesting point based on FPGA was designed to achieve the goal of the realtime monitoring in the field of nation defense, astronomy and industry. This system was constructed with base of FPGA(filed programmable gate array), including acquisition of temperature signal, storage of data, transmission of data and displaying of data . The temperature analog signal is converted into digital one which is stored into FIFO(first in first out)in the smart sensor. The data in FIFO is transferred with Bluetooth protocol to PC. Finally PC is in the charge of displaying of data. With the support of this system the personnel not only can monitor the realtime temperature without checking by themselves, but also can analyze the data recorded.
Liang Kai , Yi Yingping , Tang Chunhui , Wei Zhuo
2017, 40(10):238-242.
Abstract:The thermal imager based on uncooled infrared focal plane technologyis widely used in the field of noncontact temperature measurement with its low price and small size. The current thermal imagers can detect different temperaturebut it hard to obtain the specific temperature of the targets. Besides, the thermal imagerswhich has completely packaged is expensive and hard to redevelop. Based on these problems, a thermal imaging system was built based on FPGA and MATLAB,a method to obtain the temperature detection algorithm was provided in this paper. This method can obtain the electrical signal to specific temperature algorithm and its key coefficient. The experimental results show the error of the temperature algorithm is so small that it has a strong engineering significance for temperature detection warning systems.
Yang Guang , Zhu Zhongming , Liu Jing , Li Feng , Wang Chaoyu
2017, 40(10):243-247.
Abstract:The MK60FN1M0VLQ15 32bit microcontroller with cortex-M4 core is designed as the core control unit (MCU). The 0V7725 digital camera is used to extract the runway realtime image. With the Omron rotary encoder as the speed detection device, the brushless DC motor is used as the transmission, Steering control with a steering gear and 7.2 V lithium battery constitute the entire motion control system. In the software design, the slope of the image center line is used to find the best path. The PD control algorithm is used to deal with the steering gear and the PID control algorithm to adjust the speed of the DC motor. Thus completing the entire system of closedloop control.
Li Lianlian , Cheng Peng , Feng Man , Yang Litian , Qin Haohao , Jiang Xianfeng
2017, 40(10):248-251.
Abstract:Based on the model of tension variation in transmission line, the paper calculates the change in the horizontal component and the vertical component and develops online monitoring system of transmission line galloping. Based on conductor structure, the pressure sensor adapted to line measurement is designed. The system exports digital signal of tension variation through A/D transformation. Based on ZigBee wireless transmission technology, the function of tension variation is realized. Finally through certain comparison test of transmission line, it is proved that the measurement system can effectively implement the transmission line galloping. When the wind speed is greater than 6.7 m/s, the galloping.amplitude of conductor is positively correlated with the wind speed. When the wind speed is 12 m/s, it reaches a maximum of 6.1 m. As the wind speed increases, the amplitude of the wire is oscillating.
Liu Jian , Wang Wenjiang , Chen Xuan
2017, 40(10):252-254.
Abstract:The threephase PWM inverter, as the research object, the failure characteristics of IGBT open circuit fault was in depth studied. By comparing the normal and fault between the signal and the phase voltage, integral algorithm based on phase voltage is established. And the diagnosis and orientation method is put forward. Finally, the threephase bridge inverter model is constructed in Matlab / Simulink, through the simulation of the circuit to the method of the research, we can see that the method used in this paper can be very accurately to get the fault location from the results.
2017, 40(10):255-258.
Abstract:This paper first introduces the measurement of the core components of the thermal conductivity sensor used in nitrogen, and the influence of measuring thermal conductivity of nitrogen analyzer detection accuracy are analysed, then for each of the possible causes of low accuracy put forward concrete improvement methods, through improvement on the design and implementation of each item, finally the various parts of the application of improved measuring instrument of nitrogen, measured by the corresponding signal through the experiment of measuring speed and precision are analyzed and compared. Experiments show that the measurement of nitrogen side speed of improved faster and more accurate, practical and feasible improvement scheme.
Editor in chief:Prof. Sun Shenghe
Inauguration:1980
ISSN:1002-7300
CN:11-2175/TN
Domestic postal code:2-369