Oscillator with High Harmonic Suppression Using Split Quarterwave Microstrip Resonator

This letter presents a new type of resonator, namely, the split quarterwave microstrip resonator (SQMR), to improve the poor harmonic suppression and low Q‐factors in conventional quarterwave microstrip resonators. An oscillator incorporating the proposed SQMR is designed, fabricated, and tested to demonstrate that, not only the second harmonic suppression, but also the phase noise of the oscillator can be improved. The oscillator with the SQMR shows improved second harmonic suppression of –74.59 dBc and phase noise figure of merit of –169.77 dBc/Hz at 1 MHz offset.     

Microstrip Interdigital Hairpin Resonator With an Optimal Physical Length

In this letter, we report a novel microstrip interdigital hairpin resonator by having the parallel coupled lines in a conventional miniaturized hairpin resonator replaced by an interdigital capacitor. Equations are derived in order to design the resonator with an optimal physical length. It will be proved that the novel resonator can achieve even more size reduction than the conventional miniaturized hairpin resonator owing to the employment of the slow-wave structure. Finally, a four-pole cross-coupled bandpass filter using the optimal resonator is fabricated as verification     

Dual-Mode Microstrip Open-Loop Resonators and Filters

A miniature dual-mode microstrip open-loop resonator is proposed. Distinct characteristics of this new type of dual-mode resonator are investigated using full-wave electromagnetic simulations. It is shown that the two operating modes, i.e., the even and odd modes, within a single dual-mode resonator of this type do not couple. It is also found that there is a finite-frequency transmission zero inherently associated with the even mode. Two two-pole filters using this type of dual-mode resonator are demonstrated with opposite asymmetric responses, which result from different locations of the transmission zero. Higher order filters of this type are also investigated. Both simulated and measured results are presented.     

一种新型开路环谐振带通滤波器

利用开路环终端的内部电容耦合效应,提出一种结构紧凑,具有小型化和良好的二阶和三阶谐波抑制能力的开路环谐振器窄带带通滤波器.分析了开路环终端电容内部耦合结构变化对带通滤波器谐波抑制特性的影响,并利用上述结构仿真和设计了一个中心频率为1.5 GHz的带通滤波器,模拟结果与实验结果吻合良好,验证了滤波器的设计思想.     

Electronically Reconfigurable Dual-ModeMicrostrip Open-Loop Resonator Filter

A new type of reconfigurable asymmetric frequency response bandpass filter using dual-mode open-loop resonator is investigated. It explores the unique characteristic of the dual-mode open-loop resonator whose two operating modes, i.e., the even- and odd-modes do not couple. Thus, tuning the passband frequency is accomplished by merely changing the two modal frequencies proportionally, which makes the electronic tuning simple. Furthermore, for a single filter of this type, its selectivity can be electronically reconfigured to exhibit a higher selectivity with a finite-frequency transmission zero on either side of the passband. For the demonstration, both simulated and measured results are presented.     

Miniaturized Microstrip Wilkinson Power Divider With Harmonic Suppression

A microstrip Wilkinson power divider with harmonic suppression and size reduction is presented in this letter. The proposed power divider not only effectively reduces its occupied area to 36.5% of the conventional design at 2.65 GHz but also has higher order harmonics suppression. From the measured results, a 29 dB suppression for the third harmonic and a 34 dB suppression for the fifth harmonic are achieved while maintaining the characteristics of a conventional Wilkinson power divider. Based on a 15 dB return-loss criteria, the measured fractional bandwidth is 48%. At an operation frequency of 2.65 GHz, the insertion losses are better than 3.4 dB, the return loss is 27 dB, and the isolation is better than 22 dB.      

The Microstrip Open-Ring Resonator

The open-ring microstrip resonator is analyzed by utilizing the two-dimensional magnetic wall model. The solution and the numerical results for the eigenvalues and the electromagnetic fields for various resonant modes are presented. It is shown that the experimental results are in good agreement with the theoretical predictions based on this model.     

基于双模开环谐振器的双频带滤波器设计

基于开环双模谐振器设计了一种双频带通滤波器,由两个中心重合的正方形开口环谐振器组成。分析该谐振器的奇偶模谐振频率与传输零点,每个通带内有两个谐振模式。该滤波器中心频率分别为4.5 GHz和6.5 GHz,3 dB相对带宽FBW分别为11%、5%,两通带带内插入损耗分别小于0.6 dB、1.4 dB,带内回波损耗分别优于19.5 dB、16.5 dB,高频处阻带抑制达到50 dB,两通带之间隔离度达到53 dB,尺寸仅为6 mm×11 mm×1.09 mm。     

A Microstrip Resonator With Slotted Ground Plane for Complex Permittivity Measurements of Liquids

A novel microstrip resonator is designed to measure complex permittivities of liquids with medium loss. The enclosed resonator is based on a lambda/2 open-circuit microstrip line with a slot in the ground plane. It is immersed into the liquid under test to measure the S-parameter from 2.2 to 2.6 GHz. The complex permittivities of binary liquid mixtures of methanol and ethanol are reconstructed from the resonant frequency and the unloaded quality factor. The experimental results agree with reference values. The maximum errors are 4.4% and 8.6% for the real and imaginary part of the permittivity, respectively.     

An Open-Loop Test of a Resonator Fiber Optic Gyro

谐振式光纤陀螺是基于光学Sagnac效应来测量载体旋转角速度的一种新型传感器.利用调相谱检测技术,建立了谐振式陀螺的开环响应测试系统.利用自行研制的锁相放大器和反馈控制电路,得到了线性度很好的解调曲线.从解调曲线的线性工作区可进一步得到系统的动态范围高达 4.2～-4.2rad/s.通过对顺时针和逆时针光路采用不同的频率调制,成功地观察到对应两个不同旋转方向的陀螺开环响应输出信号.最后,对系统的零漂进行了测试,在5s时间内观察到系统的零漂为0.02rad/s.     

谐振式光纤陀螺开环响应测试

谐振式光纤陀螺是基于光学Sagnac效应来测量载体旋转角速度的一种新型传感器.利用调相谱检测技术,建立了谐振式陀螺的开环响应测试系统.利用自行研制的锁相放大器和反馈控制电路,得到了线性度很好的解调曲线.从解调曲线的线性工作区可进一步得到系统的动态范围高达+4.2～-4.2rad/s.通过对顺时针和逆时针光路采用不同的频率调制,成功地观察到对应两个不同旋转方向的陀螺开环响应输出信号.最后,对系统的零漂进行了测试,在5s时间内观察到系统的零漂为0.02rad/s.     

Design of Novel Compact Coupled Microstrip Power Divider With Harmonic Suppression

A new microstrip power divider (PD) is proposed which consists of a pair of parallel coupled-lines (PCLs) on a defected ground, and its two outputs are connected by a resistor and a capacitor. The even/odd-mode analysis shows that the defected ground structure (DGS) etched on the ground plane of PCL is equivalent to a strong parallel resonance circuit in the case of even-mode, and a weak inductance in the case of odd-mode. So, this kind of additional reactance effect is used intentionally to design compact coupled microstrip PD with harmonic suppression. Also, the phase-delay through the PD is discussed, which is different from conventional one. A 0.9 GHz PD is developed and experimental results verify it has low insertion loss, good impedance matching and isolation. Furthermore, the third harmonic suppression of this PD is better than ${-}35$ dB and the overall area of divider is only 34% of the conventional case.      

基于枝节加载开环谐振器的带阻滤波器设计

提出了一种具有良好谐波抑制功能的双枝节加载开环谐振器,加载枝节采用均匀阻抗结构,与同尺寸的开环谐振器相比,结构更紧凑,能够更好地抑制寄生模,而且可以达到更低的谐振频率。分析了加载枝节参数对带阻滤波器抑制二次谐波的影响。通过在加载的双枝节间引入集总可变电容,可以使谐振器具备谐波抑制性能的同时,实现中心频率可调的功能。基于双枝节加载环谐振器设计出一种可调带阻滤波器,中心频率可以在900MHz ~2. 65GHz 范围内调节,而且最低寄生阻带能够抑制到8GHz。     

微带发夹型谐振器滤波器的实验研究

微带发夹型谐振器滤波器具有尺寸小、成本低、易于集成等优点,在微波平面电路的设计中有着良好的应用前景.此前已有一些文献对这类滤波器进行过研究,但一般都是只针对某一种特定的发夹型谐振器进行滤波器的分析设计,而没有对各种不同谐振器的性能指标与滤波器设计要求进行比较研究.本文使用几种不同的发夹型谐振器和不同耦合方式分别设计了三阶和四阶带通滤波器,通过实验对这几种谐振器滤波器进行了分析研究,得到了一些具有实际应用价值的结论.     

Mutual Coupling Reduction in Microstrip Patch Antenna Arrays Using Simple Microstrip Resonator

Wireless Personal Communications - In this paper a novel ladder resonator is introduced to reduce mutual coupling effect in the patch antenna array structure. Applied patch antennas are operating...     

Coupling Coefficient Between Microstrip Line and Dielectric Resonator

A formula of the coupling coefficient between a dielectric resonator and a microstrip line is derived from an analysis of the transmission characteristics of the microstrip line coupled to the dielectric resonator. A practical method of calculation is developed using Fourier analysis. The calculated values show good agreement with the experimental values.     

Novel Dual-Mode Microstrip Triangular Patch Resonator Bandpass Filter

Journal of Communications Technology and Electronics - Some new characteristics of microstrip equilateral triangular patch resonator with fractal defection are analyzed, and novel fractal bandpass...     

The Microstrip Double-Ring Resonator (Short Papers)

The resonance frequencies and the fields of a microstrip double-ring resonator are discussed. It is shown that no pure even or odd mode can be excited on the resonator. Therefore it is concluded that the rnicrostrip double-ring resonator principally cannot be used to measure the phase velocities of the even and the odd modes on a coupled microstrip line.     

基于双枝节“U”型谐振器的双频段微带带通滤波器

利用一种新型的双枝节"U"型谐振器结构,设计了一款双通带微带带通滤波器。该谐振器是在"U"型谐振器的中间和侧臂上各引入了一个枝节得到的,调节侧臂上枝节的特性导纳能够在不改变一次谐波与基波频率比f_1/f_0的情况下自由改变二次谐波与基波频率比f_2/f_0的值,该特性能在实现指定的双通带的同时获得较好的带外抑制性能。对中心频率分别为0.9GHz和1.36GHz,相对带宽分别为12%和4%的双频段的微带带通滤波器进行了仿真和测试,测试结果与仿真结果吻合良好,证实了该双枝节谐振器的有效性。     

宽阻带三模谐振器微带带通滤波器设计

介绍了一种新颖的微带三模谐振器,由该谐振器构成的微带滤波器具有较宽的通带以及较好的带外抑制。对传统的单模微带环形谐振器结构进行优化,使谐振器在通带内具有三个谐振点,并且在通带边缘有四个对称衰减极点。引入的阶梯阻抗谐振单元使得微带三模谐振器具有良好的带外抑制。依据传输线原理对宽阻带三模谐振器进行了分析,并完成了中心频率为1090 MHz的宽阻带带通滤波器设计和加工,其实际测试结果与软件仿真结果具有良好的一致性。