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Crosstalk elimination in multi-view autostereoscopic display based on polarized lenticular lens array

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Chinese Physics B 2015年第1期24卷 309-314页

作者：王志远侯春萍 school of Electronic information engineering Tianjin University

An autostereoscopic display composed of a directional backlight, an image display panel, a striped half-wave plate,and a polarized lenticular lens array is proposed. The directional backlight emitting the parallel light can redirect the cones of light to lenticular lens array and reduce the chromatic spatial-interference effect. The striped half-wave plate, located in front of the image display panel, transformed the polarization direction of the lights from the directional backlight into two mutually perpendicular directions. The polarized lenticular lens array not only can divide the light from the left and right view images to send to left and right eyes but also can reduce the crosstalk of the stereoscopic images. The proposed autostereoscopic display can produce high quality stereoscopic images without crosstalk at the optimal viewing distance.

关键词： crosstalk elimination stereoscopic display lenticular lens

Codebook design for uplink of densely small cells

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Journal of Systems engineering and Electronics 2014年第4期25卷 531-537页

作者： Weikai Tan Aihuang Guo Wei Luo Wenjuan Sheng Yeqing Qian school of Electronics and information engineering Tongji University

The shrinking of cell-size brings significant changes to the wireless uplink of densely small cells （DSCs）. A codebook design is proposed that utilizes the strong line of sight （LOS） chan- nel component existing in a DSC system for uplink of the DSC system. To further improve the uplink performance, the high-rank codebook is designed based on singular value decomposition （SVD） due to the unnecessary preservation of strict constant modulus in the DSC system. And according to the simulation result, the proposed codebook leads to significant sum-rate gain and appreciable block error rate （BLER） performance improvement in the DSC system.

关键词： densely small cell (DSC) codebook design uplink,line of sight (LOS).

Computation of satellite clock-ephemeris augmentation parameters for dual-frequency multi-constellation satellite-based augmentation system

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Journal of Systems engineering and Electronics 2018年第6期29卷 1111-1123页

作者： CHEN Jie HUANG Zhigang LI Rui school of Electronic and information engineering Beihang University

Dual-frequency multi-constellation(DFMC) satellitebased augmentation system(SBAS) does not broadcast fast correction, which is important in reducing range error in L1-only ***, the integrity bound of a satellite at low elevation is so loose that the service availability is decreased near the boundary of the service area. Therefore, the computation of satellite clockephemeris(SCE) augmentation parameters needs *** propose a method introducing SCE prediction to eliminate most of the SCE error resulting from global navigation satellite system GNSS broadcast message. Compared with the signal-inspace(SIS) after applying augmentation parameters broadcast by the wide area augmentation system(WAAS), SIS accuracy after applying augmentation parameters computed by the proposed algorithm is improved and SIS integrity is ensured. With global positioning system(GPS) only, the availability of category-I(CAT-I)with a vertical alert level of 15 m in continental United States is about 90%, while the availability in the other part of the WAAS service area is markedly improved. With measurements made by the stations from the crustal movement observation network of China,users in some part of China can obtain CAT-I(vertical alert limit is 15 m) service with GPS and global navigation satellite system(GLONASS).

关键词： dual-frequency multi-constellation(DFMC) satellitebased augmentation system(SBAS) orbit determination integrity

Deterministic bound for avionics switched networks according to networking features using network calculus

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Chinese Journal of Aeronautics 2017年第6期30卷 1941-1957页

作者： Feng HE Ershuai LI school of Electronic and information engineering Beihang University

The state of the art avionics system adopts switched networks for airborne communications. A major concern in the design of the networks is the end-to-end guarantee ability. Analytic methods have been developed to compute the worst-case delays according to the detailed configurations of flows and networks within avionics context, such as network calculus and trajectory approach. It still lacks a relevant method to make a rapid performance estimation according to some typically switched networking features, such as networking scale, bandwidth utilization and average flow rate. The goal of this paper is to establish a deterministic upper bound analysis method by using these networking features instead of the complete network configurations. Two deterministic upper bounds are proposed from network calculus perspective: one is for a basic estimation,and another just shows the benefits from grouping strategy. Besides, a mathematic expression for grouping ability is established based on the concept of network connecting degree, which illustrates the possibly minimal grouping benefit. For a fully connected network with 4 switches and 12 end systems, the grouping ability coming from grouping strategy is 15–20%, which just coincides with the statistical data(18–22%) from the actual grouping advantage. Compared with the complete network calculus analysis method for individual flows, the effectiveness of the two deterministic upper bounds is no less than 38% even with remarkably varied packet lengths. Finally, the paper illustrates the design process for an industrial Avionics Full Duple X switched Ethernet(AFDX) networking case according to the two deterministic upper bounds and shows that a better control for network connecting, when designing a switched network, can improve the worst-case delays dramatically.

关键词： Deterministic bound Grouping ability Network calculus Networking features Switched networks

Hierarchical Feature-Based Detection Method for SAR Targets Under Complex Environment

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Chinese Journal of Electronics 2017年第3期26卷 647-653页

作者： GAO Fei MA Fei LUO Xiling WANG Jun SUN Jinping school of Electronic and information engineering Beihang University

A reliable target detection method for Synthetic aperture radar(SAR)images is needed urgently with the wide application of SAR *** performance of conventional detection algorithms,such as Constant false alarm rate(CFAR),degrade significantly in low SCR or complex regions while the Human visual system(HVS)can identify targets of interest without knowing characteristics of the background even in complicated *** combination of HVS with the SAR-ATR system may effectively achieve real-time multi-target detection in complex occlusion scenes.A new effective target detection algorithm is put forward using hierarchical characteristics of *** by different roles of the retina and visual cortex in the HVS,this detection algorithm is divided into coarse detection and fine detection *** kinds of features based on the correlation between target features and suspicious targets,namely overall feature and refined feature,are used in these two stages respectively to extract real *** results verify its correctness and effectiveness in complex environment.

关键词： Synthetic aperture radar(SAR) Targets detection Human visual system(HVS) Complex background Hierarchical model and X(HMAX)

An Approximate Maximum Likelihood Algorithm for Target Localization in Multistatic Passive Radar

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Chinese Journal of Electronics 2019年第1期28卷 195-201页

作者： WANG Jun QIN Zhaotao GAO Fei WEI Shaoming school of Electronics and information engineering Beihang University

This paper addresses the problem of target localization using Bistatic range(BR) measurements in a distributed multistatic passive radar system. The rangebased positioning technique employs multiple transmitterreceiver pairs, which provide separate BR *** on the Maximum likelihood(ML) function,an efficient algebraic Approximate maximum likelihood(AML) algorithm for single target localization is *** closed-form AML solution has neither initial condition requirements nor convergence difficulty. Simulations are included to compare its performance to that of the CramerRao lower bound(CRLB) and the Two-step Weighted least squares(TS-WLS) algorithm. The proposed method is shown to be able to achieve the CRLB accuracy under Gaussian measurement noise. It is more robust to noise than the TS-WLS method, and presents relative insensitivity to target-sensor geometry.

关键词： Bistatic range(BR) measurement Multistatic passive radar Target localization Approximate maximum likelihood(AML) algorithm Maximum likelihood(ML) function

Fuzzy working state evaluating function and its algorithm for analogue circuits

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The Journal of China Universities of Posts and Telecommunications 2015年第1期22卷 83-88页

作者： Huang Liang Song Wei school of Electronic and information engineering Beijing Jiaotong University school of information engineering Minzu University of China

The working state （WS） evaluation is a valuable task in the process of failure diagnosis in the analogue circuits. A fuzzy evaluating algorithm was proposed to quantify the working condition of analogue circuit regarded as fuzzy system. Several familiar WS evaluating functions based on fuzzy membership functions were also proposed to calculate the local working state indexes （WSI） of each node in an analogue circuit. The decision function combined with the WS evaluating functions is used to synthesize all the local WSI to the global WSI of the whole circuit. An example was presented to verify that the working status of the analogue circuits can be described by the new WS evaluating algorithm and the global WSI objectively and accurately.

关键词： analogue circuit working state fuzzy theory membership function

CGNet:cross-guidance network for semantic segmentation

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Science China(information Sciences) 2020年第2期63卷 49-64页

作者： Zhijie ZHANG Yanwei PANG school of Electrical and information engineering Tianjin University

Semantic segmentation is a fundamental task in image analysis. The issue of semantic segmentation is to extract discriminative features for distinguishing different objects and recognizing hard ***, most existing methods have limitations on resolving this problem. To tackle this problem, we identify the contributions of the edge and saliency information for segmentation and present a novel end-to-end network, termed cross-guidance network(CGNet) to leverage them to benefit the semantic segmentation. The edge and saliency detection network are unified into the CGNet, and model the intrinsic information among them, guiding the process of extracting discriminative features. Specifically, the CGNet attempts to extract segmentation, edge, and salient features, simultaneously. Then it transfers them into the cross-guidance module(CGM) to generate the pre-knowledge features based on the modeled information, optimizing the context feature extraction process. The proposed approach is extensively evaluated on PASCAL VOC 2012,PASCAL-Person-Part, and Cityscapes, and achieves state-of-the-art performance, demonstrating the superiority of the proposed approach.

关键词： semantic segmentation fully convolutional networks pyramid network edge detection saliency detection cross-guidance

Archimedean copula estimation of distribution algorithm based on artificial bee colony algorithm

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Journal of Systems engineering and Electronics 2015年第2期26卷 388-396页

作者： Haidong Xu Mingyan Jiang Kun Xu school of information Science and engineering Shandong University

The artificial bee colony （ABC） algorithm is a com- petitive stochastic population-based optimization algorithm. How- ever, the ABC algorithm does not use the social information and lacks the knowledge of the problem structure, which leads to in- sufficiency in both convergent speed and searching precision. Archimedean copula estimation of distribution algorithm （ACEDA） is a relatively simple, time-economic and multivariate correlated EDA. This paper proposes a novel hybrid algorithm based on the ABC algorithm and ACEDA called Archimedean copula estima- tion of distribution based on the artificial bee colony （ACABC） algorithm. The hybrid algorithm utilizes ACEDA to estimate the distribution model and then uses the information to help artificial bees to search more efficiently in the search space. Six bench- mark functions are introduced to assess the performance of the ACABC algorithm on numerical function optimization. Experimen- tal results show that the ACABC algorithm converges much faster with greater precision compared with the ABC algorithm, ACEDA and the global best （gbest）-guided ABC （GABC） algorithm in most of the experiments.

关键词： artificial bee colony(ABC) algorithm Archimedean copula estimation of distribution algorithm(ACEDA) ACEDA based on artificial be