A production insensitive compact power divider

Power dividers are inevitable components in most microwave systems. Well known topologies like Wilkinson power divider are widely studied in the literature. An “all 50 ohm power divider” is another topology presented in the some works. In this study, an all 50 ohm structure is taken as the basis and a compact-easy to implement modification the power divider is proposed. A sample structure is designed, implemented and measured to prove the topology. The decreased sensitivity to production tolerances is demonstrated by various design modifications. Comparisons with well-known topologies are given for reference.     

Waveguide to microstrip line transition and power divider

A novel waveguide to microstrip line transition and power divider with a planar structure is presented. The transition and power divider is designed on both sides of a single layer dielectric substrate, and can be used as a feed of an array antenna with a waveguide feed structure or as a complete integration of waveguide components with active components such as MMIC. Experimental results are shown and compared with simulations; it is shown that good return and insertion loss characteristics are obtained for the K-band     

Electric-magnetic-electric slow-wave microstrip line and bandpass filter of compressed size

This paper presents a novel integrated microstrip low-loss slow-wave line. The new microstrip replaces the conventional metal strip by composite metals paralleling the electric surface and magnetic surface (MS). The MS made of an array of coupled inductors shows a high-impedance state in the stopband, below which the propagation properties can be well controlled by varying the dimensions of the electric surface and MS. The dispersion curves obtained by matrix-pencil analyses closely correspond to those obtained by scattering-parameter extraction. Theoretical results, as confirmed experimentally, indicate that an increase of over 60% in the slow-wave factor can be achieved without sacrificing propagation losses, using the proposed structure. This electric-magnetic-electric (EME) microstrip is insensitive to the alignment position of the periodical structure, and can be constructed using conventional printed-circuit-board fabrication processes and integrated with other microwave components in a multilayered circuit. A compact EME bandpass filter (BPF) with suppressed harmonic responses is presented. The length of the filter is reduced by 26%, and the measured insertion loss and fractional bandwidth is comparable to that of a conventional microstrip BPF on the same substrate.     

Dual-frequency power divider with isolation stubs

A novel dual-frequency power divider with isolation stubs is presented. To reduce the parasitic effects between the two stubs that are connected by the isolation resistor in traditional Wilkinson power dividers, a structure consisting of isolation stubs is proposed. The corresponding design equations are obtained to calculate the design parameters of the desired dual-frequency power divider. Finally, this design concept is validated by experimental results on a 0.95/2.09 GHz dual-frequency power divider.     

Novel compact parallel-coupled microstrip bandpass filters with lumped-element K-inverters

Novel compact parallel-coupled microstrip bandpass filters are proposed by using additional lumped inductors to realize K-inverters between coupled-line sections to achieve an equivalent to the quarter-wavelength (/spl lambda//4) resonator filters. As a result, the filter order can be doubled without increasing the circuit area, and no repeated passband is observed at twice the center frequency. In addition, by introducing the cross-coupling effect, two transmission zeros at upper and lower stopbands may be created. Simple equivalent-circuit models are also established as effective design tools. Specifically, several compact fourth-order microstrip bandpass filters with good stopband rejection are implemented and carefully examined.     

Improved and compact 0.7 GHz tune-all bandpass filter

A compact tune-all bandpass filter is presented. This electronically tuned filter is based on series-coupled slow-wave resonators. It allows wide simultaneous and continuous tunings of centre frequency (+/-15% around 0.7 GHz) and bandwidth (from 50 to 100 MHz) with insertion loss IL<5.4 dB and return loss RL>11 dB. This two-pole bandpass filter exhibits also a very small surface of only 7.3times10^-3 lambda₀ ² and a -20 dB stop-band that extends up to 10 GHz     

A wideband compact parallel-strip 180/spl deg/ Wilkinson power divider for push-pull circuitries

A Wilkinson power divider with a differential output implemented in parallel-strip-line (PSL) is proposed. Taking full advantages of the PSL technology and a three-stage cascaded design, more than 170% impedance and isolation bandwidths are obtained. Inherent to the PSL structure, the 180/spl deg/ differential output is frequency-independent. A class-B push-pull power amplifier employing the devised concept is designed, showing a peak efficiency of 44% over a 4-GHz bandwidth. Without exploiting any extra and external low-pass filters, the proposed design can produce startling second-harmonic suppressions (more than 50dB) over the whole working dynamics and operated bandwidth.     

A novel microstrip square-loop dual-mode bandpass filter with simultaneous size reduction and spurious response suppression

In this paper, a new capacitively stepped-impedance resonator(CSIR) is proposed to develop the microstrip square-loop dual-mode bandpass filter. Using this new design, simultaneous size reduction and spurious response suppression for the dual-mode bandpass filter can be achieved. An analytical formulation of this novel resonator is given in order to elucidate the spurious frequencies relocation design. Together with this formulation, a generalized dual-mode bandpass filter model is developed so as to ease the analysis of transmission zero and insertion loss. A prototype filter is designed at 900MHz with 1.5% fractional bandwidth. Significant spurious suppressions up to 33 and 35 dB are measured at 1.8 and at 2.7 GHz, respectively. A circuitry size reduction of 54% is achieved when compared with that of the conventional structure. Moreover, the CSIR allows frequency tuning and, thus, a varactor-tuned filter is designed and a measured tunable center frequency between 1.5-1.62GHz is demonstrated. Utilizing the proposed structure, not only size reduction,as well as spurious response suppression, but also center frequency tuning can be achieved.     

A novel couple-type power divider with large-angle low-losscharacteristics

A novel large-angle low-loss direction-coupler type power divider with designed ratio between output waveguides is proposed. The radiation loss is greatly reduced by using a micro-prism at the bend corner to compensate the phase mismatch due to bending. A normalized transmitted power of the power divider with a bend angle of 10° simulated by the semivectorial beam propagation method is about 93%, which is much larger than those were reported for single-mode waveguides. Application of more micro-prisms is also shown. The calculated loss of a symmetric large-angle 3-dB directional coupler with eight micro-prisms is less than 0.953 dB     

高功率低损耗六路功分器的设计与分析

针对高功率微波对功率放大器轻重量和小体积的要求,采用基于功率分配合成技术中的同相叠加原理,设计了一种C波段的结构紧凑型窄带6路功率分配器。该分配器通过射频同轴N型连接器输入射频信号,通过环形无氧铜窄带线等相均分为6路。利用CST软件对该器件进行了初步结构优化设计和S-parameter模拟仿真,理论传输系数为-7.78 dB。结果表明,该器件能承受5.0~5.3 GHz的工作频率,功率容量达到1 000 W,各端口的功率传输效率达到97.5%以上,插入损耗为0.2 dB以内,完全可以满足使用要求。     

Low-loss and compact V-band MEMS-based analog tunable bandpass filters

This paper presents compact V-band MEMS-based analog tunable bandpass filters with improved tuning ranges and low losses. For compact size and wide tuning range, the two-pole filters are designed using the lumped-elements topology with metal-air-metal (MAM) bridge-type capacitors as tuning elements. Capacitive inter-resonator coupling has been employed to minimize the radiation loss, which is the main loss contributor at high frequencies. Two filters have been demonstrated at 50 and 65 GHz. The 65-GHz analog tunable filter showed a frequency tuning bandwidth of 10% (6.5 GHz) with low and flat insertion losses of 3.3 /spl plusmn/ 0.2 dB over the entire tuning range.     

220kV电网紧凑型线路的带电作业

进入21世纪,我国工业的发展取得了辉煌的发展成就,但是工业的发展要得到电力的保障,尤其是为了不影响正常的工业生产就要求在保障输电线路正常工作的情况下完成带电作业。本文正是对220KV电网紧凑型线路的发展背景以及研究分析了传统进入电场作业的方法,并且根据220KV紧凑型电网线路进入电场的难点研究出了新的进入电场带电作业的方法,对于在这种线路上带电作业有一定的帮助。     

Microwave photonic filter with single bandpass response

A new microwave photonic filter that solves the problem of realising a single bandpass RF response is presented. The filter is based on using phase modulation together with a pair of gratings, and eliminates the baseband response and periodic spectral response of typical FIR filters. Experimental results demonstrate a single passband square-type bandpass filter response, and operation to high frequencies.     

Wilkinson power divider with extended ports for dual-band operation

A new dual-band operation scheme is proposed for the Wilkinson power divider. Each port of the divider is extended through a transmission line section to achieve dual-band operation over a wide range of band-ratios with enhanced bandwidth for small band-ratios. Exact formulas are presented in a simple form for the design and analysis of the divider with experimental verification.     

Phase-coherent frequency divider with high speed-gain/power figure-of-merit

A phase-coherent transformer (PCT) enabled 22 GHz dynamic frequency divider in 0.18 mum CMOS with 16 dB power gain, 7 dB phase noise reduction and superb speed-gain/power FOM of 2times10²/pJ is demonstrated. The on-chip PCT enforces energy reverberation between the sensing/latching stages and enhances the frequency divider efficiency by eliminating the `slave' stage and the buffer amplifiers     

一种微带结构的新型不等分功分器设计

为了满足天线阵波束赋形对各单元天线输入功率不等分配的要求,基于Wilkinson功率分配器设计理论,详细推导并给出了任意功分比情况下隔离电阻的计算公式,补充了目前参考资料中对于直接多路输出功分器的设计指导。通过引入二分之一波长微带传输线,提出了一种微带结构的新型不等分功率分配器的设计方法。基于此方法,实现了一款应用于海事卫星通信天线阵馈电网络的功分比为1∶2∶1的三路不等分功分器。仿真和实测结果表明,功分器在工作频带范围内具有良好的性能指标。     

Fully integrated unequal Wilkinson power divider with EBG CPW

In this paper, a CPW with electromagnetic bandgap (EBG CPW) is newly proposed for designing a transmission line with high impedance. After designing, fabricating, and evaluating the characteristic impedance of the proposed EBG CPW transmission line, it will be applied to an integrated unequal Wilkinson power divider. In the EM simulation, the EBG-CPW transmission line with 10 /spl mu/m in line width has the same characteristic impedance as a CPW with a line width of 2.5 /spl mu/m. The insertion and return losses of the fabricated power divider with a power ratio of 1 to 3 are less than -0.7 dB and -15 dB, respectively. It also has excellent isolation characteristics with more than -20 dB. The experimental results are good agreement with the simulation.     

Enhanced periodic structures with compact size

Enhanced planar periodic structures with compact size, i.e. electromagnetic bandgap structures, in the microwave region, with T-type loaded capacitance realised by microstrip line are presented. The simulated and measured results show that the proposed periodic structures have not only compact size but also improved band rejection characteristic.     

CPW-fed ultra-wideband antenna with compact size

A coplanar waveguide (CPW)-fed ultra-wideband (UWB) antenna with compact size is presented. The entire size of the antenna is as small as 30times13times1.6timesmm. The measured and simulated impedance bandwidth defined by voltage-standing wave ratios <2 is from 3.1 to more than 10.6 GHz. The proposed antenna exhibits a nearly omni-directional radiation pattern with very compact size, which is suitable for various portable UWB systems.     

A miniaturized Wilkinson power divider with CMOS active inductors

A miniaturized Wilkinson power divider implemented in a standard 0.18-/spl mu/m CMOS process is presented in this letter. By using active inductors for the circuit implementation, a significant area reduction can be achieved due to the absence of distributed components and spiral inductors. The power divider is designed at a center frequency of 4.5GHz for equal power dividing with all ports matched to 50/spl Omega/. Drawing a dc current of 9.3mA from a 1.8-V supply voltage, the fabricated circuit exhibits an insertion loss less than 0.16dB and a return loss better than 30dB at the center frequency while maintaining good isolation between the output ports. The active area of the miniaturized Wilkinson power divider is 150/spl times/100/spl mu/m/sup 2/, which is suitable for system integration in monolithic microwave integrated circuit (MMIC) applications.