Wideband Polarization Reconfigurable Dielectric Resonator Antenna

A wideband polarization reconfigurable dielectric resonator antenna excited by quasilumped quadrature coupler (QLQC) is proposed.By adjusting the value of varactor diode on the QLQC feed network,both the wideband LP and CP dielectric resonator antennas (DRA) modes can be achieved.By selecting a different feed port,left-and right-handed CP conversion can be realized.It is found that the 10 dB impedance bandwidth of the LP and CP modes are 10.1％ and 44.9％,respectively.For the CP mode,a very wide 3 dB axial ratio bandwidth of 37.7％ can be obtained which is much larger than that of the microstrip patch counterpart (3.8％).It is worth mentioning that the wideband CP DRA has a stable broadside radiation pattern across the whole operating band where the boresight gain is larger than 3 dBi.     

一种识别雷达用半集总参数LTCC双工器

介绍了一种基于低温共烧陶瓷(LTCC)工艺研制而成的小型化半集总高隔离度双工器.该双工器由L波段集总参数低通滤波器和X波段阶跃阻抗( SIR)分布参数带通滤波器组成.通过电磁仿真软件的仿真优化,实际加工滤波器的测试结果与软件仿真结果吻合.其中低通滤波器1dB截止频率为1.46GHz,带通滤波器中心频率为8.3GHz,1dB带宽为0.6GHz,通带内插损小于3.5dB,X波段端口对L波段端口隔离度大于60dB.该小型化LTCC双工器已成功应用于某毫米波战场识别系统的T/R组件中.     

频率选择表面的等效电路设计方法综述

本文回顾了频率选择表面(FSS)等效电路的理论发展,分析了将其应用于提高FSS设计效率的必要条件,重点介绍了利用具有准集总电感和准集总电容效应的元件,依据等效电路设计实现一系列高性能带通、带阻、单频和多频FSS 的方法。理论和实测结果表明:这类FSS普遍具有极小的尺寸,良好的入射角和极化稳定性,而且谐振频率、带宽和极化特性独立可控;同时,单元结构参数和等效电路参数之间的解析关系式为FSS的快速优化提供了条件,从而为FSS 设计提供了从构建到优化的高效解决途径。     

Performance profile comparison of the quasi-lumped element resonator antenna

The performance profile comparison of the quasi-lumped element resonator antenna is presented. The specific advantages of this antenna are investigated by comparing it to the standard long wire antenna approach, and, in particular, also to the many available differently loaded wire antenna approaches, which are also optimized for maximal radiation efficiency and directivity for example, the capacitively loaded long wire antenna and the planar H-shaped elements loaded transmission line design. It was noted that the quasi-lumped element resonator antenna formed by small interdigital capacitors and line inductors proved to be compact in size with an aperture size of 5.8 × 5.6 mm² and better directional characteristics.     

一种回退效率增强宽带Doherty放大器的设计

提出给主功放分配多的功率来提高Doherty回退范围的功率转换效率。建立了数学模型，从理论上验证了回退范围的效率提高。电路测试证明，回退6 dB漏极效率大于59〖WT《Times New Roman》〗%〖WTBZ〗，高同类宽带Doherty 7个百分点，峰值输出功率46.5 dBm。另外，对类集总传输线的解析公式进行修正，校正了原来公式在理论计算中存在的32.5〖WT《Times New Roman》〗%〖WTBZ〗的误差确，缩短了设计时间，降低了设计难度。     

Dual-band bandpass filter based on mixed electric and magnetic coupling of the hybrid quasi-lumped resonator

A novel compact dual-band bandpass filter based on mixed coupling of the hybrid quasi-lumped resonator is proposed. The filter is composed of two independent signal paths, each can generate one passband with two identical hybrid quasi-lumped resonators. The proposal combines the mixed electric and magnetic coupling technology with this novel resonator in the filter design. Analysis of the filter has been done with the equivalent circuit method. To validate the approach, a dual-band bandpass filter operating at 2.4/5.2 GHz has been fabricated. Both passbands were realised with mixed coupling. An additional transmission zero is generated at either passband. Final fabricated filter has good band skirt, low insertion loss and good out-of-band performance. Reasonable agreement is found between the calculated, simulated and measured results. The implementation area is 0.21λ_g × 0.12λ_g.