一种用于毫米波相控阵的单馈点方形切角贴片天线

对适用于毫米波相控阵的单馈点电磁结构的圆极化贴片天线单元进行了系统设计。该设计对轴比、阻抗带宽和轴比带宽折衷考虑,取得了21．4％的阻抗带宽,6．6％的3dB轴比带宽,带宽内最高增益值为7．5dB,满足了设计要求。     

一种新的GPS双频微带天线

通过在贴片上开等长度的十字缝隙的方式,设计了一种小型化的GPS双频微带天线。仿真结果表明,天线长和宽较开缝前分别减小了28.9%和35.4%,且在1.227GHz和1.575GHz两个频段点处,回波损耗分别达到了-23.2dB和-15dB。天线辐射性能良好,结构简单易于实现。     

一种平面开槽超宽带天线的设计与研究

提出了一种新型的小型超宽带(UWB)指数渐变开槽天线,此天线用180°微带线相移器馈电网络馈电,研究了其相移器馈电网络的转接特性和反射损耗. 并在辐射部分的前后端分别开小槽缝,改善了带内特性,进一步展宽了天线的频带,使天线的带宽大于3∶1(S11＜ -10 dB).方向图在整个带宽范围内具有较好的方向特性,并在X波段具有良好的对称端射特性,在中心频段增益大于10 dB.     

一种双频双极化微带天线的设计

介绍了一种工作在S波段的新型双频双极化天线,该天线采用探针馈电的方式．通过贴片边缘和中央开缝的方法实现了天线的双频双极化。使用HFSS对该天线进行仿真、优化．得到了较好的结构参数。与传统双频双极化天线结构相比．该天线具有较好的双频特性,相对轴比带宽可以达到4．5％。     

单馈等功分周视压缩波导缝隙天线

针对无线电引信波导缝隙天线和馈电网络不满足小型化、一体化设计的问题,提出单馈等功分周视压缩波导缝隙天线。该天线由压缩波导缝隙阵列和E-T波导分支构成,谐振式工作,采用单馈输入等功率分配及双辐射阵元面,实现功分网络与天线一体化;通过对E-T波导分支增加尖劈结构改进,两天线间隔离度提高4dB。经Taylor综合法优化缝隙分布,优化后较均匀分布主副瓣比提高4.5dB。实测结果表明该天线最大增益13.05dB、H面宽度23°、E面最大零深宽度≤10°,与仿真结果基本一致。     

Ka波段宽带圆极化微带天线单元及阵列设计

设计了一种基于矩形缝隙耦合的Ka波段圆极化微带天线单元,分析了各参数对轴比特性的影响;为改善天线的轴比带宽和圆极化纯度,采用顺序旋转馈电技术,设计了4×4宽带圆极化微带天线阵列。仿真结果表明,该天线阵列具有良好的宽带特性,其阻抗带宽(S11<-10dB)达25%(31.4～40.2GHz),轴比带宽(AR<3dB)达17%(31.8～37.8GHz)。     

一种双馈圆极化微带天线的设计

设计了一种具有移相功分网络的双馈圆极化微带天线,辐射采用矩形微带贴片,移相功分网络采用带状线.通过构造两个方向正交、幅度相等、相位差为90°的两个电场分量,从而实现天线的圆极化性能.天线工作在S波段,具有超过40％的阻抗匹配带宽(VSWR≤2)和20％的圆极化带宽(AR≤3 dB),天线增益在±60°内大于-1 dB的带宽达到12％.最终将四个天线进行组阵工作,利用四通道对天线进行比相,达到二维测向的功能.     

一种新型弹载共形多极化天线的设计与实现

为满足弹载共形天线宽波束的要求,设计了一种新型多极化天线。该天线有工作在圆极化和线极化的两个端口,分别由圆形贴片和加载圆盘的单极子天线实现,可接收空间三个互相正交的电场分量。通过在圆形贴片和圆盘间短接铜柱对单极子天线的匹配进行调节。实测结果表明,圆极化和线极化端口回波损耗小于-10dB的频率范围为1.21～1.85GHz和1.54～1.61GHz,轴比小于3dB的带宽为1.45～1.8GHz,端口间隔离度大于15dB。该天线结构紧凑,剖面低,能够满足弹载共形天线的要求。     

一种新型圆极化缝隙加载三角形微带天线

为了提高圆极化微带天线性能,提出一种新型圆极化微带天线结构,通过在三角形贴片上加载缝隙和枝节展宽圆极化带宽,天线总体尺寸为0.74λ0×0.88λ0×0.09λ0。HFSS仿真结果表明该天线阻抗带宽(回波损耗S11-10 d B)9.6%,圆极化带宽(轴比AR3 d B)5.4%,轴比最小值0.23 d B,增益最大值8.11 d Bic。该天线的圆极化性能较好,在卫星导航和无线通信中具有很好的应用潜能。     

小型化宽频带圆极化半圆形微带贴片天线

针对无线通信中单贴片圆极化微带贴片天线带宽很窄的问题,提出了小型化半圆形宽频带圆极化微带天线。该天线通过在半圆形辐射贴片上开一组尺寸和位置非对称的矩形槽实现圆极化,应用非共面的临近耦合馈电补偿馈电探针的电感展宽天线的带宽。仿真结果表明,在2.30~3.04GHz范围内,天线的回波损耗小于-10dB,阻抗带宽27.7%;在2.37~2.54GHz范围内,天线的轴比小于3dB,圆极化带宽6.9%;在宽带范围内天线的增益大于6dB。与圆极化E形微带天线相比,不仅提高了带宽,而且贴片面积缩小了40%。     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

Open Rule-setting System Applied to Conceptual Design of Engines

Open rule-setting method advanced in this paper concentrates on providing designers of engines with a convenient way to express their design innovations and develop the expected prototypes in the early CAD stage, and constitute effective models for the following analysis process of CAE and CAPP. The problems arisen in the process of conceptual design with the traditional experience-based development method are analyzed. Based on those analyses, open rule-setting method is presented and some associated technical problems are discussed. The functional framework of open rule-setting system was built as software engineering methods. The speciality of the engine product as a kind of complex product and the requirement of the engine product based on its structural particularity to rule-setting system are considered carefully. A demonstration is supplied to illustrate how the open rule-setting method enhances the efficiency and quality of the engine conceptual design.     

Research on Linux Network Device Driver

By analyzing the working principle of Linux network device driver, discussing the Linux network driver structure and its key technologies, the general network driver structure and its design methodologies in Linux system are summarized. Through modifying the network device driver of Linux device driver 3rd version snull, c and improving the COW technology, the Zero-Copy technology in Linux （kernel version 2.6.11 ） is implemented. In the end, the success test tells us that the thorough analysis of network device driver is the foundation of many applications, and it also provides a certain improvement to a lot of real applications, even to military application development.     

Improvement and Experiment of the Reamer in Vibra Cutter Against Wave Edge of Titanium Sheet Alloy Parts

By analyzing the influencing factors of part quality making of sheet alloy of titanium by vibra cutter, the shape of upper reamer is set as cylinder and wedge-shaped form, and the lower reamer as plain and hemicycle form, and its main structural parameters are defined as well. Then it is validated further that such improved vibra cutter reamer can be used to process curve-edged parts of titanium alloy sheet. The experimental result shows that the titanium alloy sheet parts processed by above equipment have no sharpen angles for convex parts and evident crevasse of concave-edged part. In summary, such improvement can eliminate the free-waved edge and improve the manufacture quality of titanium alloy sheet parts greatly.     

Experimental Study on the Small Flyer Initiating Behavior of Fine-grained Explosives

The initiating behavior of fine-grained explosives by small flyer is studied. The diameter of small flyer in this device is 1 ram. The test results indicate that the granularity of explosives has great effect on its flyer initiating sensitivity.The flyer initiating sensitivity of the fine-grained explosives is higher and the critical initiating energy is lower than that of common explosives. For common explosive, the flyer initiating sensitivity increases as the density is reduced. But for the fine-grained explosive, the test results are exactly opposite.     

Algorithm for Multi-laser-target Tracking Based on Clustering Fusion

Multi-laser-target tracking is an important subject in the field of signal processing of laser warners. A clustering method is applied to the measurement of laser warner, and the space-time fusion for measurements in the same cluster is accomplished. Real-time tracking of multi-laser-target and real-time picking of multi-laser-signal are introduced using data fusion of the measurements. A prototype device of the algorithm is built up. The results of experiments show that the algorithm is very effective.     

Influence of Installing Error on the Surface Shape Precision of the Axial Symmetry Aspheric Workpiece in Lapping

A method to calculate the surface shape error, which is caused by the installing error between the workpiece and the lapping tool in the process of form lapping, is proposed. The mathematical model which the installing translation error influences on the workpiece surface shape error is established. The changing rule of the error is simulated through the calculating example of the paraboloid workpiece. The results indicate that the surface shape error of the workpiece is increasing with the increase of the installing translation error, it is also increasing gradually along the center point of the curve surface to the edge, and the influence is severer to the curve surface with great curvature than that of the small curvature when the translation error is the same.     

Experimental Research on Output Performances of Giant Magnetostrictive Actuator

The paper introduces the performances of magnetostrictive actuators and its applications, discusses the design methods for the structure and internal magnetic circuit of a giant magnetostrictive actuator, and makes tests on the output displacement and force characteristics for an actuator using homemade magnetostrictive material. The experimental result shows that the actuator has satisfactory output precisions and ranges in transient and stable states, and can be used in lowfrequency vibration control system of precise equipment.     

Robust Graded Sliding Mode Tracking Control for Low Speed Spinning Ballistic Missiles

The nonlinear dynamic model of spinning ballistic missiles is established during the first boosting phase of the missile. Based on the conventional backstepping sliding mode control and the assumption of a two time-scale separation of missile dynamics, a graded sliding mode controller is designed with two sub-sliding surfaces which have invariability to external disturbances and parameter perturbations, and a matrix which comprises three first order low pass filters is introduced to prevent ＂explosion of terms＂. Owing to the upper bounds of the uncertainties are difficult to obtain in advance, adaptive laws are introduced to estimate the values of the uncertainties in real-time. Eventually, the numerical simulation results given to show the proposed controller can ensure the steady flight of missiles.