Floquet ports : these periodic ports enable designers of phased - array antennas and frequency - selective surfaces to obtain separate fields into modes for better understanding and examine phase information for each mode 傅里叶端口:这种周期性的端口可以使相控阵天线和频率选择表面的设计者能够得到不同传输模式下的场型,从而能够更好地理解和验证每种模式下的相位信息
The mutual coupling between phased array antennas elements causes the loss of reflected power . following the changes of scanning angle , mutual coupling between elements will also change , so the comensation of mutual coupling should become difficult 相控阵天线单元间由于互耦效应引起的反射功率损耗,随着扫描角的变化而随之发生变化,这给互耦补偿带来了极大地困难。
Phased array radar is a detective system with multiple function , high reliability and adaptive ability , spatially the rapid scan and beam shape change characteristic of phased array antenna made its application more and more abroad 相控阵雷达是一种具有多功能、高可靠性和自适应能力的探测系统,尤其是相控阵天线所具有的波束快速扫描能力和波束形状快速变化能力等优点,使得相控阵雷达得到了越来越广泛的应用。
Digital t / r module use dds ( ddfs and ddws ) technique to implement amplitude and phase weighting , it can achive transmitting beamforming in if or lower frequency by using digital method whitch realizes phase control and amplitude weighting 数字t / r组件利用dds技术实现了雷达的信号产生和幅相控制,可以在中频甚至更低的频率上用数字的方法实现幅度加权和相位控制,从而真正地实现相控阵天线发射波束的全数字控制。
Particular mathematic analysis is made about the characteristics and modeling methods of phased array antenna , especially of the density - weighted antenna . theory analysis and simulation are made about the circular ? caliber weight , circular - tylor distribution and bayliss circular ? caliber weight 相控阵天线部分是整个雷达系统的关键环节,天线方向图仿真的准确与否直接影响到整个雷达系统仿真的准确性和精度。
With the development of digital technique , the function that can only be implemented by analog circuits or analog technique , now can be implemented by digital circuits or digital technique . the procedure of phased shifting in phased array radar will become a digital procedure eventually 随着数字技术的发展,原先只能用模拟电路实现或在模拟电路部分实现的功能也可以用数字电路或在数字信号处理部分实现,相控阵天线的移相过程最后可能会成为一个数字过程。
According to the reciprocal characteristic of dual - mcde reciprocal ferrite phase shifters , the antenna only requires to provide the sa : lle beams of operation between the trtinsmit and receive beams . in addition , 1he phased shifter can operate in various polarizations such as linear polarization or circular polarization , which is adiipted to the development of modern ra ( 1ar technologies 对电扫描相控阵天线来说，双模互易式铁氧体移相器的互易特性可使收、发在同一特定波束位置上工作；此外，双模互易铁氧体移相器可以在线极化、圆极化等多种极化方式下工作，适应了现代雷达技术的发展。
This thesis in combination with the actual engineering demand , analyzes and designs a horizontally polarized triangular - grid planar phased array antenna , which composed of open - ended rectangular waveguide , the main steps of analyzing and designing are as follows : 1 . at first , taking no account of mutual coupling among the array elements , classical electromagnetic theory is used to establish analyzing model for finite array , and initial value parameters of the array structure which basic satisfy the design index are got , these parameters provide reference for subsequent analyzing and design 本论文结合实际工程需要,分析和设计了一个采用水平极化方式的三角形栅格矩形波导相控阵天线,其主要步骤如下: 1 .首先,在不考虑阵列单元间互耦影响的情况下,采用经典电磁理论建立有限阵列分析模型,通过分析得到了基本满足设计指标的阵列结构参数,为后续的分析、设计提供参考。
The directivity coefficient of the phased array antenna has been generalized and discussed . according to the formulations of microstrip antenna design theory , planar and cylindrical microstrip patch cell has been analyzed . we can conclude that the cylindrical microstrip patch cell has the performance of high gain , low thickness , high resonant frequency , uniform directivity diagram , and easy fabrication on missile body , so it is a good choice 本文根据微带天线设计理论,分析了平面和柱面两种微带贴片单元,其中柱面微带贴片单元增益高、厚度小、谐振频率高、方向图均匀,且较易加工制作在弹体上,适合在相控阵天线中做共形辐射单元。
With compensation of signal ’ s time delay from different radiating element by phase shifters , phased - array antenna can control array beam easily . because there are no mechanical devices for rotating beam , the phased - array antenna system can scan everywhere in beam covered areas in millisecand by stepping the phase shifters . it improves the tracking velocity of antenna towards the object , and becomes the development trends of weapon system antennas 相控阵天线利用移相器补偿信号到达辐射单元时间的差异,从而控制波束方向;天线没有机械旋转问题,只需改变移相器的设定值,波束便可以在毫秒级内扫描其覆盖空域内的任何地方,提高了天线对目标的跟踪速度,是目前武器系统天线的发展方向。
