By adjusting the relative positions between the body and the antenna , some interesting results were obtained , which are suggested to be useful for a reasonable distribution of the plane - antennas 通过对机身和天线之间不同相对位置下天线辐射特性的分析，得出了机载天线方向图的一些规律。
On the assumption that a cabin and a horn antenna were under the bottom of an airplane , fdtd method was applied to analyze the antenna patterns which are generally affected by the body of the airplane 摘要假定飞机腹部加装了某一形状的炮舱和矩形喇叭天线，用时域有限差分法( fdtd )分析了这样的外形对天线辐射特性的影响。
That is to say , high frequency modulational field radiated from the antenna system of moving bodies influents the charge distribution in plasma , while the disturbance of the charge distribution influents the field conversely 也就是说，在压缩区内，飞行体天线辐射出的高频调制场，影响着等离子体中的电荷分布，而电荷分布的扰动又反过来影响场量。
Often , mode conversion techniques are used to change the undesirable mode to one that results in a radiation pattern with a boresight peak such as circular te1 1 or rectangular te 01 mode 因此研究轴对称模式的天线辐射技术具有重要意义。辐射天线的工程设计方案通常有三种:模式转换器+普通喇叭、 vlasov天线和cobra ( coaxialbeam - roatatingantenna )天线。
The hardware of the system is sum up with the purchased television aerial , agilent 8482h power sensor , dsp , oscillograph , etc . for the software part , the architecture takes advantage of the mathematical rule of both the antenna ’ s radiation field and electromagnetic field , for example , the finite - difference time - domain ( fdtd ) method 硬件电路设计调试方面,利用购置电视天线、 aglient8482h功率传感器和dsp 、示波器等组成系统等进行试验。在软件仿真中,本文重点介绍并且综合应用了天线辐射场的计算方法和电磁场的数值计算方法? ?时域有限差分( fdtd )方法。
In addition , the mom - po hybrid method is proposed to dissect radiation from radome - enclosed antennas and the correction impedance matrix upon which the solution to equivalent currents of radome ' s surface depend is built . a comparative analysis of those methods is finally presented to examine respectively their accuracy as well as computational efficiency 最后，对矩量法物理光学法的混合算法分析问题的过程进行讨论，给出混合算法分析带罩天线辐射问题的具体解决方案，建立混合算法求解天线罩表面等效电磁流的校正矩阵。
First , the method of aperture integration - surface integration , which is based on physical optics theory , is used to study the radiating property of the 3 - d radome - enclosed antennas . secondly , the moment method is employed to analyze the electromagnetic radiation from radome - enclosed antennas with axi - symmetric revolving radome 然后应用矩量法针对具有回转体结构天线罩的带罩天线辐射进行分析，分析过程中利用回转体特点，采用适当的基函数将三维问题转化成二维问题解决，以降低计算量提高计算效率。
The video simulator is of significant flexibility and commonality . so long as the simulation software is changed , simulation of different radar signals can be implemented . the video simulator can dominate radio frequency ( rf ) equipment to export rf pulse to implement the function of radar signal environment integrated simulation system 模拟器控制射频设备输出的射频脉冲,既可作为注入信号直接输入雷达侦察接收机,也可以放大到足够的功率后通过天线辐射,作为微波暗室的辐射源,实现雷达信号环境一体化仿真系统的功能。
Since complicated differential and integral operations were involved in the kernel of the integral equation , we simplified the equation and got the nakano equation . as instances , the planar archimedean spiral antenna , the planar equiangular spiral antenna , the monofilar helical antenna , the conical helical antenna with fixed ascending angle and the conical equiangular - spiral antenna were analyzed through the moment method . all of the results matched fairly well with the references and experiment results 这种方法的积分方程的积分核里含有复杂的微积分运算，为了简化计算，本文在推广的海伦积分方程的基础上，对方程进行了简化，推导了nakano方程，并以平面阿基米德螺旋天线，平面等角螺旋天线，轴向模圆柱螺旋天线，具有固定升角的圆锥螺旋天线和圆锥等角螺旋天线为例，用矩量法求解了天线上的电流分布，研究了螺旋天线辐射的宽频带特性，所得的结果均与参考文献吻合很好。
Secondly , the article begins with changing the original chip and selects a new type of chip , max1479 , which has more emission power , constitutes a new communication protocol , and designs the circuit and program . in the end , this article analyses the influence of environment on the antenna . meanwhile , it also analyses characteristic of the antenna by using electromagnetic theory , and then designs a kind of inverted - f antenna 其次,本文从射频芯片改型入手,选用一款专用于汽车电子并具有更高发射功率的射频芯片max1479 ,重新制定通信方案,设计硬件电路并编程调试;最后,本文分析了环境因素对天线辐射的影响,应用天线和电磁场理论对天线的特性进行分析,设计一种倒f型天线和螺旋天线相结合的天线结构,并用hfss软件和cst软件仿真。
