基于LTCC的Ka波段带通滤波器的设计

设计了一种基于低温共烧陶瓷技术带状线形式的Ka波段带通滤波器,该滤波器被埋入11层的基板中。提出一种类同轴结构来减小共面波导到带状线转换之间的阻抗不连续性。整个带状线滤波器采用了金属直通孔来实现接地和屏蔽功能。测试结果表明,滤波器中心频率为34.69GHz,带宽1.73GHz内最大插入损耗为-4.5dB,通带内回波损耗低于-13.45dB。该测试结果包含两个射频接头。整个滤波器尺寸为9.8mm×5mm×1.056mm。这种紧凑埋置式的结构和测试结果表明,该带状线滤波器适合于毫米波多芯片组件的应用。     

一种适用于超宽带通信的微带垂直转换结构

该文提出一种适用于超宽带电路的基于过孔的微带垂直转换结构。通过在过孔附近的电源层上蚀刻平面电磁带隙单元来抑制电源分配网络谐振,降低其在过孔处的自阻抗,以改善垂直互连结构传输性能。将互连结构分解为过孔处耦合的微带线结构和电源平面对结构,并使用网络分析方法快速估算系统传输性能。仿真和实验测试表明,在3.1-10.6 GHz的超宽带频段内过孔的插入损耗小于0.4 dB。与在电源分配网络之间添加短路过孔方法相比,该结构在传输性能相当的前提下减少了一个布线层,从而降低了设备成本。     

Modeling and design for electrical performance of wideband flip-chip transition

A locally matching technique is proposed in this paper to improve the wideband performance of the flip-chip transition. The gap width of the coplanar waveguide (CPW) line in the bump pad region of both the chip and board is enlarged for achieving larger inductance to compensate the capacitance at the transition, making the approximate impedance close to 50 /spl Omega/. An equivalent circuit is derived from the frequency response of the transition simulated by Sonnet and is used to control the zero frequency of the structure. With a properly chosen value of the enlarged width, the zero frequency can be controlled to achieve an optimal transition performance over an as wide as possible bandwidth. A systematic design procedure is established and employed to design a transition over a band from dc to 60 GHz. The design and simulation results are also compared with the measured data of a scaled structure as well as a realization of an optimized flip-chip transition design ranging from dc to Ka band. The measured data show a good agreement with the simulation results, if under a careful calibration procedure. Both demonstrate that the present transition design can achieve better than 25 dB in return loss and 0.2 dB in insertion loss over dc to 35 GHz.     

A Broadband CPW-to-Microstrip Modes Coupling Technique

A broadband vertical transition from coplanar waveguide (CPW)-to-microstrip modes is presented. The transition has a double resonance and can be tuned for very wide-band operation. The CPW-to-microstrip modes coupling technique is useful for the vertical integration of multi-layer millimeter-wave circuits, packaging and antenna feeding networks. A vertical transition has been fabricated on 100 μm silicon substrate for operation at W-band frequencies and shows less than 0.3 dB of insertion loss and better than 12 dB of return loss from 75 to 110 GHz. A 94 GHz CPW-fed microstrip antenna showing a 10-dB bandwidth of about 30 % has been built using the same transition technique.     

Low-Loss and Wideband Package Transitions for Microwave and Millimeter-Wave MCMs

This paper presents high-performance flip-chip, through-substrate via and board-level BGA transition designs applicable in microwave and millimeter-wave multichip module (MCM) assemblies. Full-wave electromagnetic analysis was performed to achieve optimized transition structures. Interconnection test structures were fabricated in ceramic substrates and their performance was validated using on-wafer scattering parameter measurements. Both the flip-chip transition and the through-substrate via transition with a height of 800 mum exhibited return losses better than 25 dB and 20 dB, respectively, with low transmission losses up to 50 GHz. Furthermore, the wideband board-level BGA transition with a standoff height of 500 showed low insertion loss (< 0.5 dB) over a wide frequency range, from direct current (dc) up to 32.5 GHz.     

一种宽频带低损耗内监测网络的设计

介绍了一种小型化宽带低损耗内监测网络,该内监测网络位于相控阵雷达的T/R组件与天线之间,采用串馈形式,通过缝隙耦合将发射接收信号耦合输出。天线与组件之间的互联直通路采用同轴形式降低损耗,监测耦合路采用微带线形式减小体积,通过改变耦合缝隙的尺寸来调节耦合强弱,通过旋转耦合缝隙角度来调节耦合器的定向性,通过优化耦合区域微带线的线宽实现阻抗匹配。采用全波仿真方法对定向耦合器进行了优化设计,在12~18 GHz的频率范围内,端口的回波损耗均小于-20 dB,通带内耦合度在-32^-29.5 dB之间,定向性大于20 dB,性能指标优良;对所设计的内监测网络进行实物加工与试验验证,测试结果与仿真结果相吻合。     

低成本宽带90°巴伦的研究与设计

提出并设计了一种低成本宽带90°巴伦电路结构,电路由宽带耦合威尔金森功分器、弱耦合线和扇形阶跃阻抗谐振器级联的宽带90°移相器组成。利用电磁仿真软件HFSS对工作在中心频率为1.65GHz 的微带电路进行建模和仿真。采用PCB工艺制作了电路实物并利用矢量网络分析仪进行测试;对比得出仿真与测试结果十分吻合,该巴伦实测相对带宽大于117.0% (0.65～2.58GHz),带内各端口回波损耗好于12.6 dB,输出端口隔离度大于13.1dB,带内插入损耗小于0.5 dB,相位误差小于90°±7.6°。与现有的结构和设计相比,该巴伦不仅具有更大的工作频带和单层电路布局,而且具有容易加工、成本低的优点。     

An HTS Wideband Filter Using Interdigital-Like Resonators at UHF Band

A wideband superconducting interdigital-like filter at UHF band has been successfully designed and fabricated. An interdigital-like resonator is proposed to realize both strong coupling and compact size. A ten-pole demonstration high temperature superconducting filter is developed with a center frequency of approximately 340 MHz and a fractional bandwidth of 26%. The measurements show that the insertion loss of the filter is less than 0.2 dB, the return loss is better than 17 dB, and the out-of-band rejection is better than 70 dB.      

Wideband coplanar waveguide-to-rectangular waveguide transition using fin-line taper

This letter introduces a new wideband coplanar waveguide-to-rectangular waveguide transition. The transition uses a uniplanar circuit in line with the waveguide, which eases the design and fabrication. The design does not require airbridges. Simulations and measurements of X-band (8.2-12.4 GHz) transitions based on both a low- and high-permittivity material (/spl epsiv//sub r/= 2.33 and 10.8) show that the transition works fine over the full frequency band. For /spl epsiv//sub r/= 2.33 the measured return and insertion loss of a back-to-back transition are more than 16 dB and less than 0.4dB, respectively. The corresponding values for /spl epsiv//sub r/= 10.8 are more than 10 dB and less than 1.0 dB, respectively, over 90% of the frequency band. The measured insertion loss values indicate losses of less than 0.14 dB and 0.36 dB at the center frequency for a single transition on a substrate with /spl epsiv//sub r/= 2.33 and 10.8, respectively.     

小型化宽频带宽阻带微带滤波器的设计

目前研究宽频带微带滤波器的文献很多,但普遍不能同时具有宽频带和宽阻带的性能,且带内回波损耗大,带外抑制差。为此,提出了一种新型的宽频带微带滤波器。该滤波器采用在E型阶跃阻抗谐振器( SIR)中引入U型结构的方法,实现其宽频带宽阻带的性能。对滤波器进行仿真、加工与实测,仿真结果与实测结果吻合良好。加工得到的滤波器3 dB带宽为7.1 GHz,低于-20 dB的高频阻带为9.3 GHz,带内回波损耗低于-23.2 dB,实物尺寸为15 mm伊8.5 mm,具有小型化的特点。实测数据表明,提出的滤波器具有良好的性能,在工程领域具有实际的应用价值。     

A wideband coplanar stripline to microstrip transition

A wideband coplanar stripline (CPS)-to-microstrip line was developed. The transition has a simple structure for the ease of fabrication with low cost. The measured performance of two back-to-back transitions exhibits an insertion loss of less than 3 dB and a return loss of better than 10 dB over a bandwidth from 1.3 GHz to 13.3 GHz (1:10.2). For narrower bandwidth, an insertion loss of less than 1 dB with a return loss of better than 10 dB was achieved from 1.4 GHz to 7.3 GHz (1:5.2)     

一种采用有源电感的可调增益小面积超宽带低噪声放大器

设计了一款采用可调谐有源电感（TAI）的可调增益的小面积超宽带低噪声放大器(LNA),输入级采用共基极结构,输出级采用射随器结构,分别实现了宽带输入和输出匹配;放大级采用带有反馈电阻的共射共基结构以取得宽的带宽,并采用TAI作负载,通过调节TAI的多个外部偏压使LNA的增益可调。结果表明,该LNA在2~9GHz的频带内,通过组合调节有源电感调节端口的偏压可实现S21在16.5~21.1dB的连续可调;S11小于-14.7dB;S22小于-19.3dB;NF小于4.9dB;芯片面积仅为0.049mm2。     

A dual-feed dual-band L-probe patch antenna

By embedding shorting vias, a dual-feed and dual-band L-probe patch antenna, with flexible frequency ratio and relatively small lateral size, is proposed. Dual resonant frequency bands are produced by two radiating patches located in different layers, with the lower patch supported by shorting vias. The measured impedance bandwidths, determined by 10 dB return loss, of the two operating bands reach 26.6% and 42.2%, respectively. Also the radiation patterns are stable over both operating bands. Simulation results are compared well with experiments. This antenna is highly suitable to be used as a base station antenna for multiband operation.     

紧凑型4×4单元超宽带MIMO缝隙天线设计

为了更好地实现移动终端天线小型化,提出了一种具有较高单元间隔离度的紧凑型超宽带（multiple input multiple output,MIMO）天线。该天线无需任何解耦网络,通过阶梯形缝隙结构来实现各个天线单元。采用的阶梯形缝隙天线不仅减少了天线的尺寸,而且具有定向辐射行为,从而形成较高的高隔离度。提出的天线尺寸为23×23mm3。测量结果表明,提出的超宽带MIMO天线在3 GHz-10.9 GHz频谱中能够产生较好的多向辐射特性（S11≤-10dB）,阻抗隔离大于20dB,包络相关系数和信道容量损耗的容许界限保证了良好的MIMO性能。     

高速PCB单端过孔研究

在高速数字电路设计中,过孔的寄生电容、电感的影响不能忽略,过孔在传输路径上表现为阻抗不连续的断点,会产生信号的反射、延时、衰减等信号完整性问题。文章采用矢量网络分析仪研究了过孔长度、过孔孔径、焊盘/反焊盘直径对过孔阻抗的影响。通过在信号孔旁增加接地孔,为过孔电流提供回路方法,提高过孔阻抗的连续性,并有效降低过孔损耗。此外,文章还探讨了过孔多余短柱对过孔阻抗及损耗的影响。本研究可为高速数字电路过孔设计和优化提供依据。     

Design and Performance of an Ultra-Narrowband Superconducting Filter at UHF Band

A stepped impedance spiral resonator suitable for high-temperature superconducting (HTS) filter with bandwidth narrower than 0.5% is presented. An eight-pole demonstration HTS filter is developed with a central frequency of 650 MHz and a bandwidth of 0.3%. The measurements show that the insertion loss is less than 0.3 dB, and the return loss is better than 16 dB. The filter has out-of-band rejections of 65 dB at 2 MHz below the passband and 80 dB at 2 MHz above the passband, respectively.     

Dual polarization stacked microstrip patch antenna array with verylow cross-polarization

This paper describes the development and performance of a wideband dual linear polarization microstrip antenna array used in the Danish high-resolution airborne multifrequency polarimetric synthetic aperture radar, EMISAR. The antenna was designed for an operating frequency of 1.25 GHz±50 MHz and was built as an array of 8×2 probe-fed stacked microstrip patches. The feeding network is constructed in microstrip and is capable of handling 6 kW of peak input-power at an altitude of 45000 ft (unpressurized). The impedance bandwidth (return loss better than -14 dB) of the antenna is 10%, the isolation between the horizontal and the vertical ports of the array is 50 dB and the cross-polarization suppression is 40 dB. A new design principle for simultaneously achieving very low cross-polarization and low side lobes in dual linear polarization antenna arrays has been applied     

A Compact UWB Three-Way Power Divider

A three-way power divider with ultra wideband behavior is presented. It has a compact size with an overall dimension of 20 mm times 30 mm. The proposed divider utilizes broadside coupling via multilayer microstrip/slot transitions of elliptical shape. The simulated and measured results show that the proposed device has 4.77 plusmn 1 dB insertion loss, better than 17 dB return loss, and better than 15 dB isolation across the frequency band 3.1 to 10.6 GHz.     

一种X 波段磁场耦合式波导-微带转换结构

波导-微带转换器是微波集成电路和天馈线系统中的重要器件。结合具体应用,设计了一款新型、宽带磁耦合式波导-微带转换器。和传统结构相比,本设计用双层的贴片结构代替金属块状阶梯脊,通过在贴片上加载金属过孔来展宽转换的带宽;将阶梯状金属贴片和微带探针一体化设计,从而避免了焊接带来的损耗和结构不稳定,并且减小了加工难度,降低了重量和成本。测试结果表明,波导-微带转换器的两个端口在8.85～11.52GHz 的频带内回波损耗小于-15 dB,插入损耗约为0.8dB,均满足应用需求。     

Wideband Parallel-Strip Bandpass Filter Using Phase Inverter

A new wideband parallel-strip bandpass filter using phase inverter with stubs is proposed. With the wideband phase inverter in the parallel-strip line structure, the measured fractional passband bandwidth is 123% with a flat group delay response. Also, over 90% impedance bandwidth is obtained for the return loss higher than 20 dB. The theoretical simulation, electromagnetic simulation, and measured results show good agreement with this proposed design.