偶极天线

With the overview of present MIMO antenna research, the thesis brings forward a new kind of polar diversity antenna array applied in MIMO base stations, which elements are planar printed dipoles. The beamforming technology is used to obtain a particular type of elevation pattern, which has square cosecant characteristic.

本文在对目前MIMO 天线领域的研究动态进行概述的基础上，结合基站的自身特点，提出并实现了一种新型的基站极化分集波束赋形天线阵列，其阵元为平面印刷偶极子，阵列在俯仰面形成类似平方余割形式的方向图分布。

Furthermore, a size reduction rate of 50% compared with a general dipole antenna is realized.

此外，天线高度和常规偶极子天线相比减小了约50%。

This paper chooses a normal mode helical antenna to replace the short dipole antenna to improve efficiency.

本文采用法向模螺旋天线代替以前采用的短偶极子天线以提高效率。

Finally, it analyses the time complexity of the algorithm and researches how it is influenced by culture operator.3、The paper presents the evaluation standard of the GA's application capability. Basing on characters such as continuity, multi-peak, vibration, randomicity as well as large-scale, five functions are selected to test search ability and robustcity of co-evolution algorithm. Finally, it analyses the simulation result and researches the influence of algorithm brought by culture operators.4、Basing on the concept of collection overcast, it researches the task distribution issue and constitutes delaminated math model on task distribution issue. It puts out the co-evolution algorithm of subtask's decomposing. The experiment compare IGA、SGA to CN and validates the efficiency of co-evolution algorithm on the NP completeness issue.5、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.6、Being aiming at the knowledge of image model matching, it adopts single meme and real code. It puts out fast co-evolution matching algorithm strategy. Basing on NPROD resemble measurement, I emulate the indiscrimination model matching and discrimination model matching. Finally, it valuates the co-evolution algorithm's efficiency on the real code and real time search issue.

分析了算法的时间复杂度，研究了文化算子对算法时间复杂度的影响。3、提出了GA的应用性能评价标准，从连续性、多峰性、随机性、振荡性、广域性多个角度出发选择五个测试函数，对共同进化算法的搜索性能和鲁棒性作了函数优化的性能测试，分析了仿真结果，研究了文化算子对算法的影响。4、基于集覆盖的概念，研究了MAS中的任务分配问题，建立了任务分配问题的分层数学模型，给出了子任务分解共同进化算法，实验比较了IGA、SGA、CN，验证了共同进化算法对NP完全问题的有效性。5、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。6、针对图像模板匹配问题的领域知识，采用单类拟子和实数编码，给出快速共同进化匹配算法策略，基于NPROD相似度测度，仿真试验了无差别和有差别模板匹配，验证了共同进化算法对实数编码和实时性搜索问题上的有效性。

In modern specification of handset, there is one about SAR. However, current mobile phone antenna is dipole antenna with omni-directional radiation pattern in azimuth plane. So much better performance of antenna means higher SAR value. Therefore, in order to improve SAR performance, designer may be forced to detune antenna or use resistor. The two methods will reduce efficiency of antenna.

在移动电话的技术规范中往往有SAR值的要求，这给手机天线的设计带来了严峻的挑战，因为现代的手机天线基本上是在水平面具有全向辐射特点的偶极子天线，因此天线的性能越好往往SAR值越高，所以有时为了降低SAR值甚至故意劣化天线的性能。

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

When the magnitudes and directions of the electric and magnetic dipoles were matched, the radiation in backward and sideward direction was obviously restrained.

当TEM喇叭天线与低频补偿回路形成电偶极子和磁偶极子满足匹配条件时，天线低频辐射的单向性将得到提高。

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。

deviation of the antenna radiation resistance seems larger in some textbooks about the electromagnetic theory for the editors have made some similar treatment when discussing the radiation power of short antenna.combining the concept of physical with mathematical tools and the precise results are gained,that is the real radiation resistance of electric dipole antenna is about ten times smaller than that of the approximate results in the actual literature by researching the electromagnetic field theory and average energy density.this offers evidence to grasp the radiated ability accurately.

小 摘要：在部分有关电磁场理论的教材中，编者讨论短天线的辐射功率时，由于作了某些近似处理而所得天线的辐射电阻值偏差较大。从天线辐射的电磁场理论和平均能流密度出发，使物理概念和数学工具相结合，运用矢量运算推导出精确的结果，即电偶极子天线的实际辐射电阻要比文献中的近似结果小数十倍，因而为准确把握天线的辐射能力提供了依据。

The superior properties of antenna arrays composed of unequal dipoles are discovered and the method to modify the length of each element is described.

研究了由不等长的偶极子组成的天线阵的优越性，提出了调节偶极子的长度以达到设计目的的方法。

Further more, the simplified analysis method on stressed-skin effect of corrugated steel sheet is also discussed in detail.

此外还比较详细地探讨了蒙皮效应的简化分析方法。

If I had known her telephone number,I would have called her.

要是我知道她的电话号码，我就打电话给她了。