查询词典 dipole antenna

The present domestic satellite reception antenna controllers are basically designed according to the extreme value following principle. The satellite antenna controllers can aim at the satellite according to the carrier waver signals through driving the antenna to circumvolve repeatedly.

目前国内的卫星接收天线控制器大部分是按极值跟踪原理设计的，这种控制器需根据系统接收到的载波信号大小控制天线反复转动，才能对准卫星。

The hybrid antenna system also includes a displaceable antenna, such as a whip antenna, that is selectively extendable from and retractable with the casing.

该混合天线系统还包括可移动天线，它可以有选择地拉伸出或收缩入外壳中。

For verifying the design scheme of the refractive diffractive incorporate antenna system, an experiment antenna system is accomplished which is used to compare its performance with the Keplerian antenna which has being used in the CO 2 coherent laser system.

引 言随着相干激光雷达的广泛应用，对于其小型化的要求越来越突出，尤其是用于机载，弹载等携带用途的成像激光雷达要求它的系统具有小型，轻便等特点，而考虑远距离相干外差探测的特点时，则要求主振激光器具有高发射功率，光学系统具有高像质，高效率。

A new quadrifilar helix antenna is given. The antenna has four feed ports and the phase difference between two border upon ports is 90 degree. The simulation results indicate that this antenna has a good performance of axial ratio and gain pattern.

为了改善天线的轴比性能，文章提出了一种4臂等幅馈电、相位依次相差90度的天线方案，仿真结果表明，这种天线的增益特性和轴比特性都得到了较大的改善。

Delay distortion caused by log-periodic antenna can be avoided by changing its feed ing method; Reflection can be greatly reduced by resistively loading antennas as cylindrical monopole antenna,conical monopole and TEM horn antenna, resulting in better characteristics in radiating pulse signal.

改变对数周期天线的馈电方式可以避免滞后失真；根据 WU- KING偶极子理论，对圆柱单极子天线、单圆锥天线和 TEM喇叭天线等进行加载可以有效减小反射，改善了天线辐射短脉冲的性能，但同时也导致了辐射效率的降

Sectorization is extensively used in cell communication systems. A scheme combined smart antenna and sectorial antenna is proposed which is an effective method to realize sectorization together with smart antenna.

扇区化是蜂窝系统重要的覆盖方式，基于这种考虑提出了一种TD-SCDMA系统实现扇区化智能天线的方法—扇区化智能天线(SSA-Sectoral SmartAntenna)，该方法有效的解决了TD-SCDMA系统智能天线扇区化问题。

Being aim at the optimization issue of load of antenna near ground, it combines many GA strategies and puts forward strategic meme. And it puts out co-evolution algorithm of load of antenna design. And it emulates the optimization design of load of antenna near ground. Finally, it valuates the co-evolution algorithm's efficiency on the continuum search issues of multi-variable and multi-peak value.

针对近地天线加载优化设计问题，结合多种改进GA策略，提出了策略型拟子，给出天线加载设计的共同进化算法，对有耗半空间对称偶极子天线加载优化设计作了仿真实验，验证了共同进化算法对多变量多峰连续搜索问题上的有效性。

Based on these theories, this paper discusses the method of the design of the low noise amplifier integrated active microstrip patch antenna, which considers the low noise amplifier and the microstrip antenna and takes both mutual matching into account. The size of the active integrated antenna and the circuit configuration of the low noise amplifier are obtained at the specified operation frequency.

根据这些理论，把低噪声放大器和微带天线结合起来，并考虑两者之间的匹配，讨论了一种集成低噪声放大器的有源微带贴片天线的设计，得到了在给定工作频率下的有源集成天线尺寸和低噪声放大器的电路结构。

Was founded Tyrone and in 1998, fixed assets 18 million, building the production area of 30,800 square meters, is a new professional development, production and marketing of satellite communication and mobile communication antenna technology-intensive enterprises, Products widely used in satellite communications and radio and television field, has an excellent cost-effective to receive the trust of users, with the country in recent years on the antenna of the Product Quality Control,"North" antenna with a strong wind resistance, transportation convenience, and IMPREGNATION electrostatic process, with antiseptic, sunscreen, a more elegant features such as showing its powerful strength, the market brand, sales nationwide and exported to Europe, Oceania, the Middle East, Southeast Asia more than a dozen countries and regions.

廊坊兴泰隆通信器材有限公司始建与一九九八年，固定资产1800万，建筑生产面积30800平方米，是一家新兴专业研制、生产和销售卫星通信及移动通信天线的科技密集型企业，产品广泛用于卫星通信和广播电视领域，一直以优良的性价比得到广大的用户信赖，随着近年来国家对天线产品的质量控制，&中北&天线具有抗风能力强，运输方便，并采用静电浸塑工艺，具有防腐、防晒、美观大方等特点更显示出其强大实力，成为市场名牌，销售全国，并出口欧洲、大洋洲、中东、东南亚等十几个国家和地区。

The system comprises first and second antennas for receiving first and second RF signals of first and second frequencies, respectively; a mobile switch for measuring performance characteristics of the second antenna; and a switch circuit connected between the second antenna and the mobile switch for controlling flow of the first RF signal to the second antenna.

在移动通信终端内，一开关电路，用于根据工作模式控制CDMA天线的输入阻抗，该开关电路被连接在CDMA天线和移动开关之间，以便在GPS工作模式下维持CDMA天线的输入阻抗为高阻抗，来切断GPS信号的流入，以及在CDMA工作模式下维持CDMA天线的输入阻抗为低阻抗以接收CDMA信号。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。