【作者】 李民权；

【导师】 吴先良； 张玉梅；

【作者基本信息】 安徽大学 ， 电磁场与微波技术， 2007， 博士

【摘要】 双频、双极化微带天线在现代通信、微波成像、合成口径雷达和电子对抗等许多系统中具有广泛的应用,是国民经济和军事应用的迫切需求,也是当前天线领域的研究热点之一。论文对双频、双极化微带天线阵元及阵列进行了较深入研究,并对天线的理论及计算方法、优化方法进行了详细分析。提出了多种创新性设计方案,并完成了天线制作及实验测试,结果表明,所设计的天线满足实际应用要求。论文主要包括以下六方面内容：第一,采用腔体理论与传输线理论相结合对微带贴片天线进行分析,并对该方法进行了修正,给出了求解矩形及方形微带贴片天线尺寸、导纳及方向图的方法。所得结果对微带天线的工程设计具有参考价值。第二,辛时域有限差分方法(SFDTD)研究。对SFDTD方法的差分格式、吸收边界及稳定性等进行分析,并用SFDTD法研究了微带贴片天线参数对双频、双极化单元天线性能(谐振频率、回波损耗)的影响。第三,粒子群优化算法(PSO)研究。对PSO进行改进并对收敛区域进行讨论。将PSO应用到天线及阵列参数优化及方向图综合。第四,对双频双极化阵元进行研究。分析了天线结构尺寸及介质基板等对天线性能的影响。提出在微带单元上悬置寄生金属贴片来提高天线增益及降低单元之间互藕。并将这一结构应用于阵列天线,有效地解决盲角问题。采用枝节技术实现天线的宽带工作模式。第五,基于透波增强特性天线阵元设计。提出一款基于透波增强机制的X波段新颖天线阵元,研究了天线物理参数对天线性能的影响,并对所设计天线进行测量,结果表明：天线阵元增益提高了6dB,E面半功率波束宽度减小126度,前后比增加到25dB。第六,双频、双极化天线阵列设计。提出一款S/X波段阵列天线,实现1：3频比,实测阻抗带宽大于9%,极化隔离均优于25dB,交叉极化电平低于-27dB,测试结果表明某些指标优于国内水平。更多还原

【Abstract】 Dual-band dual-polarized microstrip antennas are widely applied in modern communications, microwave imaging, synthetic aperture radar, electronic confrontation and other fields. The application of them to national economic and military purposes is in urgent demand. they are also a hot topic in the field of antenna research. In this paper, the double-frequency microstrip antenna and array is studied, calculation and optimization methods are analyzed in detail. A variety of novel structures of antennas is given. The results show that the design of antennas is satisfactory. Six main subjects included are:First, microstrip antenna are analyzed using the modified theory of cavities, the formula of admittance, size and radiation pattern of microstrip antenna about rectangle and square structures is given. The results have a reference value for the engineering design of the microstrip antenna.Secondly, the symplectic finite difference time domain method (SFDTD) is studied. The scheme, absorbing boundary and stability are analyzed, the resonant frequency, reflection losses of double-frequency dual-polarized antenna are studied using SFDTD.Third, particle swarm optimization (PSO) algorithm is studied. To improve PSO and to convergence region are discussed. PSO is applied to antenna array parameter optimization and antenna pattern comprehension.Fourth, double-frequency double-polarization antenna is studied. The influence of size and medium on the performance of the antenna is analyzed. We put a parasitic strip on the major unit to improve antenna gain and reduce mutual coupling. And this structure will be used in array antenna to solve the problem of blind angle. We use matching structure to enhance bandwidth of the antenna.Fifth, Based on enhanced transmission character, a novel x-band antenna is designed. The influence of physical parameters on the performance of antenna is studied. The measurements results show that:the antenna gained6dB enhancement, E plane half power beam width reduced126degrees, the front-to-back ratio of the antenna radiation pattern increased to25dB. Sixth,A double-frequency double-polarized S/X band antenna array is designed. The antenna array has a frequency ratio of1:3, the impedance bandwidth is greater than9%, polarization isolation is better than25dB, cross polarization level lower than-27dB, and some parameters were superior to the domestic level.更多还原