查询词典 navigation radar

To solve the exsisting problems in the realization of the LFM/CW radar, the thesis presents a technique for dynamically measuring the LFM/CW signals, which can accomplish the dynamic measurements of FM linearity, FM bandwidth and FM slop of the transmitted signals of LFM/CW radars. This technique creates an effective and accurate means of judging the performance of LFMCW radars. The linearity-correction techniques presented in the thesis successfully make the linearity of the transmitted signals of an actual LFM/CW radar reduce from approximately 25% to 0. 1%(or r. m. s linearity of 0.04%), better than the best results (0.22%) obtained by foreign researchers with complex linearization closed-loop in the same kind of LFM/CW radars, according to the published literatures during the last decade. In order to improve the capability of the real-time processing and range-cells management of LFM/CW radars, the principle of equivalent mixing by lacking-sampling process of band-pass real signals is proposed based on the well-proved improvedversion of sampling theorem of band-pass real signals. This principle is used to configure the range-segments processing of the beat signals of an actual LFM/CW radar. The techniques of system-background interference suppression and the beat signal's dynamic range suppression are proposed, and are realized in an actual LFM/CW radar to demonstrate their effectiveness.

针对线性调频连续波雷达实现中急待解决的技术问题，文中提出并验证了线性调频连续波信号的综合动态测试技术，可以完成对线性调频连续波雷达发射信号的扫频线性度、扫频带宽和扫频斜率的综合动态测试，为衡量实际线性调频连续波雷达的系统性能创立了精确有效的测试手段；文中建立的非实时闭环动态校正技术使一部实际的线性调频连续波雷达的发射信号（时带积3×10〓）的扫频线性度从25%改善为0.1%（方均根线性度0.04%），优于国外已公布的80年代同类雷达中采用复杂的实时闭环动态校正环路所获得的实际结果（0.22%）；为了改善线性调频连续波雷达的实时性和分辨单元数处理能力，文中发展完善了实带通信号的采样定理并给予了严格证明，并在此基础上提出了欠采样等效混频原理，将其应用于实际线性调频连续波雷达的距离分段处理中；针对线性调频连续波雷达中系统背景干扰和回波动态范围问题，创立了系统背景综合抑制技术和频域动态范围压缩技术，并将它应用于实孔线性调频连续波雷达系统中，显示出它们的有效性。

In chapter 5, in allusion to the shortcoming of the existing high resolution radar target detection algorithm, taking the problem of high resolution radar target detection as the problem of true-false target recognition, and borrowing ideas from the dealing with novelty problem, this paper introduces one-class SVM into high resolution radar true-false target recognition for the first time. That can provide a new idea for solving high resolution radar true-false target recognition problem.

第五章针对现有的高分辨雷达目标检测算法的缺陷，将高分辨雷达目标检测问题等效为真假目标识别问题，并借鉴处理异常值问题的思想，首次将1类支持向量机引入高分辨雷达真假目标识别之中，为解决高分辨雷达真假目标识别问题提供了一条崭新的思路。

The database such as the vessel database, navigation aids facility database, hydro-meteorological information database and the database of the port facility and above–water facility in the area of responsibility are set up that the MSA can realize the vessels entering or leaving port management, above-water and underwater construction management, navigation alarm and announcement publishing, above water dangerous condition, accident , water area pollution , and vessel alarm monitoring in the area of responsibility, as well as master the circumstances in the water area of the accident and dangerous conditions and the dynamic positions of the navigation vessels.

建立了船舶数据库、助航设施数据库、水文气象数据库、港口设施、辖区水上设施数据库。实现海事局对船舶进出港管理、水上水下施工管理、发布航行警告、航行通告、监控辖区水上险情、交通事故、水域污染、船舶报警，掌握事故、险情水域情况以及有关巡航船舶位置动态。

with the development of satellite navigation communication,antenna is a very important unit,performance of the satellite navigation communication system is affected by it partly.a new type of bifilar helix for satellite navigation communication system is introduced,and the traving-wave bifilar helix is analyzed briefly.meanwhile,the design and the test results are given.the results show that the antenna possesses excellent circular hemispherical beam with wide angle circular polarization and better impedance match,and has a compact structure and high integration.it can be applied in caps systems successful.

小 摘要：随着卫星导航通信技术的迅速发展，天线作为卫星导航通信系统中的重要部分，在一定程度上决定着卫星导航通信系统的性能。介绍一种用于卫星导航通信系统的双臂螺旋天线，讲述爬行波式螺旋天线的设计过程，并给出最终测试结果。结果表明，该天线具有优良的圆对称半球波束，良好的广角圆极化特性和优良的阻抗匹配特性，其结构简单、紧凑，为通信入站回传提供了一种优良的选择。

It has strong integration capability, and has realized navigation-aids information distribution based on WEBGIS at the first time. It strongly promotes navigation-aids daily management and maintenance, and this system provides technique guarantee for ships and marine departments to acquire navigation-aids information in time, by rule and line expediently.

该系统信息资源整合能力强，并首次实现基于电子海图基础数据的航标信息发布新技术，有力地促进了航标日常管理与维护，为船舶及涉海部门及时、准确、方便获取航标信息提供了技术保障。

The inertial navigation system is needed in the development of navigation, aviation and spaceflight. Communication system is one of the most important part in the data transmission of inertial alignment, the veracity, anti-interference and secrecy of which has an impact on the navigation, especially for data transmission between the aircraft carrier and carrier plane.

航海、航空和航天事业的迅速发展离不开惯性导航系统，惯性初始对准数据的传输离不开通信系统，而数据传输的准确性、抗干扰性、高保密性是事关导航的关键，其中在航母与舰载机之间数据传输的可靠性、保密性尤为重要。

However, keywords can only represent the simple content, which easily dissever the relevancy of the content The deep-content representation and application are not developed, so semantic navigation is not satisfied at present. Time mechanism is a kind of navigation mechanisms that uses time for the signpost, and determines navigation route according to the time of occurrence.

时序机制指以时间为导航路标、根据事物发生的时间顺序确定访问路径的一种导航机制，主要应用于WWW信息空间中以时问顺序为线索组织信息的结构中；空间机制指依据对象间的空间关联，为用户指引路径，提供导航路标的机制，应用于具有空间特征的结构中；社会机制指利用先行者的经验、建议为后来者指引路径的行为，原来主要应用在推荐系统、协作系统中，目前已经在主流的信息检索系统中得到了应用，如在CNKl知识网络服务平台（CNS 5.0）中的应用。

Strapdown inertial navigation system is a kind of very advanced inertial navigation technology,and it is the developing direction of inertial navigation.

捷联式惯性导航系统是一种十分先进的惯性导航技术，是近年来惯性技术的一个发展方向。

Strap-down inertial navigation system is a kind of advanced inertial navigation technology, which is the developing direction of inertial navigation.

捷联式惯性导航系统是一种先进的惯性导航技术，是近年来惯性技术的一个发展方向。

This article has first analyzed the GPS localization navigation principle, in view of its un- voluntary navigation flaw, the analysis has compared the performance of many kinds of assistant navigation system, determined use Dead Reckoning system, composed of electronic compass and milemeter, to complete the auxiliary localization function, when GPS abated. This scheme could get a satisfying short-time precision, and its cost was low.

本文首先分析了GPS定位导航原理，针对其非主动式导航的缺陷，在分析比较了多种辅助导航系统的性能后，采用"电子罗盘+里程计"的DR航迹推算系统来完成GPS失效时的辅助定位，该方案能保证短时精度，且成本低廉。

Listen,point and check your answers.

听，指出并且检查你的答案。

Warming needle is one of effective treatment methods for knee arthralgia aggravated by cold,and it is simple,safety,so it should be developed in clinical acupuncture and moxibustion extensively.

但以本院科针灸门诊在2005年1月—2006年6月期间共收治膝痛患者100余例，经过临床的诊断后，其中施以温针治疗的48例，疗效显著，报道如下。1临床资料本组病例48