A broadband Ka-band microstrip circulator for integrated millimeter wave systems

A Ka-band microstrip circulator, using ferrite with 4π M=5000 G, have been developed. By optimizing the circulator configuration, broadband n=2 Chebyshev response performance are obtained over 7 GHz bandwidth. The circulator have isolation of greater than 15 dB, and insertion loss of less than 1.0 dB.     

All-planar dual-mode asymmetric filters at Ka-band

All-planar dual-mode inductive asymmetric filters utilizing new planar microstrip to dielectric-loaded rectangular waveguide transitions at Ka-band were presented and built in this work. The conventional, three-dimensional metallic rectangular waveguide dual-mode filters can be implemented into mature PCB technology with a much easier and lower-cost fabrication process on the basis of the all-planar feature of the transition. This work demonstrates two Ka-band filter examples with center frequency at 31 GHz and bandwidth at 1 GHz and 2 GHz. The measured minimum insertion loss of each case was, respectively, 2.68 and 1.12 dB, with greater than 10 dB return loss in the passband. Moreover, the measured side-band attenuation (near passband) is larger than 30 dB due to the transmission zeros at each side of the passband.     

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.     

A Ka-band narrow bandpass filter using LTCC technology

A Ka-band low-temperature co-fired ceramic (LTCC) narrow bandpass filter (BPF) is presented first. This BPF shows a very narrow 3 dB fractional bandwidth of 4.5% centered at 28.7 GHz. The advantages of multilayered LTCC technology such as high integration and vertical stacking capabilities were employed to design a three-dimensional interdigital end-coupled embedded microstrip narrow BPF. The difficulties in controlling the precise distance between two adjacent resonators in LTCC end-coupled BPF were overcome by locating the resonators on different layers. The measured insertion loss is 3 dB at 28.7 GHz.     

基片集成波导及其微带过渡的设计

设计了工作于毫米波频段的基片集成波导（SIW）,阐述了基片集成波导及其微带过渡的原理和结构,公式推导出过渡结构中各种参数的计算方法,通过HFSS软件进行仿真,制作了SIW与微带过渡的样品并测试,结果表明在35.5～37.5GHz范围内,波导插损为-1～-2dB,回波损耗小于-10dB,性能良好。     

微型化Ka波段环形带线谐振腔LTCC带通滤波器

提出了一种微型化Ka频段带线带通滤波器设计方案.采用带有调谐枝节的环形谐振腔和带线耦合结构,利用低温共烧陶瓷(LTCC)技术设计并研制了一个相对带宽约10.4%的Ka频段带通滤波器,典型性能为在中心频率26.99 GHz处插入损耗小于1.3 dB,带内驻波比小于1.20:1,损耗起伏小于0.30 dB,滤波器的尺寸为4...     

一种新型毫米波矩形波导-微带过渡结构

介绍了一种新颖的、适用于毫米波频段的矩形波导-微带过渡电路结构。该过渡电路具有插入损耗低、频带宽、重复性好的特性。其矩形波导E面相对于微带电路面,以及电磁信号传输方向的位置与脊波导-微带过渡相同。该过渡电路的微带线与波导的转换部分采用非接触式结构,并设计了可调节元件,从而在有一定加工误差的条件下改善其产品传输特性。利用高频仿真软件CST,在Ka频段进行了优化仿真,并对利用其优化值所设计的一对背靠背的电路实物进行了测试,在32～40 GHz的频率范围内,插入损耗小于2.36 dB,回波损耗大于7.22 dB;在整个Ka频段内,插入损耗小于3.49 dB。     

W-band CPW RF MEMS circuits on quartz substrates

This paper presents W-band coplanar waveguide RF microelectromechanical system (MEMS) capacitive shunt switches with very low insertion loss (-0.2 to -0.5 dB) and high-isolation (/spl les/ -30 dB) over the entire W-band frequency range. It is shown that full-wave electromagnetic modeling using Sonnet can predict the performance of RF MEMS switches up to 120 GHz. Also presented are W-band 0/spl deg//90/spl deg/ and 0/spl deg//180/spl deg/ switched-line phase shifters with very good insertion loss (1.75 dB/bit at 90 GHz) and a wide bandwidth of operation (75-100 GHz). These circuits are the first demonstration of RF MEMS digital-type phase shifters at W-band frequencies and they outperform their solid-state counterparts by a large margin.     

An In-Line Waveguide-to-Microstrip Transition Using Radial-Shaped Probe

In this letter, an in-line waveguide-to-microstrip transition at Ka-band is presented. It utilizes a radial-shaped probe a quarter-wavelength away from the waveguide short-back, which is also used as a support for the microstrip substrate, to terminate the TE₁₀ mode of the standard waveguide. This printed structure is easy to fabricate and convenient to be installed in the waveguide cavity with a split-block configuration. A test module at Ka-band is designed and fabricated. It provides a return loss better than 10 dB from 26.5 to 38.5 GHz and an insertion loss of 1.2 to 2 dB within a wide frequency range from 26.5 to 36.2 GHz with a low cost, easy to fabricate printed structure. The measured results show good agreement with the simulated ones.     

A high efficiency 46 to 92 GHz all microstrip frequency doubler

Using packaged GaAs varactor diodes, a high efficiency 46 to 92 GHz frequency doubler has been developed. Microstrip circuits have been used to match the input and output impedances presented by the diode. A conversion loss of 8 to 10 dB was measured. This doubler circuit is useful for W-band (75 to 110 GHz) integrated circuit receivers and transceivers. The use of microstrip circuit can drastically reduce the fabrication cost in addition to size and weight.     

横向Ka波段波导微带探针过渡的设计和优化

介绍了一种横向Ka波段宽带波导-微带探针过渡的设计,基于有限元场分析软件Ansoft HFSS对该类过渡的设计方法进行了研究。最后给出了Ka波段内的优化数据。仿真结果表明,该宽带波导-微带探针过渡在26.5G~40GHz内插入损耗小于0.065 dB,达到了设计目标。     

Design of W-Band Tripler

This paper describes a high performance W-band tripler with a novel structure. Input frequency is 25-36.7 GHz, output frequency 75-110 GHz, input power is 20dBm and conversion loss 16 dB. It can extend microwave signal to W-band (adding in Ka-band doubler). In the design, we give some approaches to achieve high band performances.     

基于微带线的W波段二次分谐波混频器设计

采用微带混合集成电路技术设计了一款W波段二次分谐波混频器.通过分析二级管封装结构引入的寄生参量,提出了一种减小二级管并联寄生电容的方法.为了避免在W波段使用传统分谐波混频器中普遍使用的过孔接地及侧边平行耦合微带线带通滤波器,提出了一种改进型分谐波混频器结构.测试结果表明混频器在本振频率为45 GHz,中频频率为2.4 GHz时单边带变频损耗最小,最小值为8 dB.射频频率在90 ～ 100 GHz测试频率范围内,变频损耗的测量值小于10.5 dB.     

W-band single-layer vertical transitions

Vertical single-layer transitions operating at W-band frequencies have been developed. The designs are uniplanar, use electromagnetic coupling, and do not require via holes or air bridges. The first transition uses coplanar-waveguide-mode coupling and results in an insertion loss of better than 0.6 dB over the whole band, with a loss of 0.25 dB from 85 to 110 GHz. The return loss is better than -10 dB from 75 to 110 GHz. The second transition uses microstrip-mode coupling and results in a 0.2-dB insertion loss over the whole W-band. These transitions can prove very useful for millimeter-wave packaging and vertical interconnects     

一种新型的毫米波功率合成电路

针对毫米波功率合成技术研究,吸取传统W ilk inson电桥的优点,提出了一种新型低损耗毫米波微带集成3dB电桥,其成本低、加工制作容易、在32GHz~37GHz,插损为0.2dB;以此3dB电桥为基础的Ka频段功率合成网络,在频率33~35GHz,合成效率达75%.     

Ka-band reflectarray using ring elements

A simple ring structure to realise a Ka-band circularly polarised microstrip reflectarray is presented. With rotation techniques employed to focus the reflected wave at a focal point, a 0.5 m right-hand circularly polarised microstrip reflectarray is developed and tested at 31.75 GHz resulting in 50% aperture efficiency. The cross-polarisation levels measured are 40.7 dB down at broadside, showing the validity of the structure.     

Wide-band PIN diode SPST switch in unilateral asymmetric finline

This paper reports the design and modelling of a wide-band, low insertion loss finline SPST switch using beam lead PIN diodes at the Ka-band. A unilateral asymmetric finline with an offset slot has been used to realize a transmission line with lower impedance to best match the impedance of the diode. Finline tapered transitions have been designed with exponential profiles for minimum reflection coefficient over the band. Wide-band operation, covering the full Ka-band, has been achieved with reactive tuning by varying the diode spacing. Four PIN diodes have been shunt mounted across the unilateral asymmetric finline slot. An insertion loss of 0.9 dB minimum and 1.65 dB maximum over the entire Ka-band and isolation of >25 dB from 26.5 to 35GHz and >20 dB over the complete Kaband has been achieved.     

Quasiplanar 3 dB hybrid for millimetre-wave integrated circuits

A quasiplanar 3 dB hybrid suitable for integration in millimetre-wave fin-line circuits is presented. The performance of the device is characterised by 0.5 dB insertion loss, less than 0.5 dB imbalance and 20?25 dB isolation over the entire Ka-band (26.5?40 GHz).     

High-isolation W-band MEMS switches

This paper presents the design, fabrication and measurement of single, T-match and π-match W-band high-isolation MEMS shunt switches on silicon substrates. The single and T-match design result in -20 dB isolation over the 80-110 GHz range with an insertion loss of 0.25±0.1 dB. The π-match design results in a reflection coefficient lower than -20 dB up to 100 GHz, and an isolation of -30 to -40 dB from 75 to 110 GHz (limited by leakage through the substrate). The associated insertion loss Is 0.4±0.1 dB at 90 GHz. To our knowledge, this is the first demonstration of high-performance MEMS switches at W-band frequencies     

高功率毫米波回旋器件实验研究

介质加载是解决回旋行波管振荡一个较好的方法,本文利用这种结构在Ka波段回旋行波管的实验中利用这种结构在工作模式TE01,加速电压66 kV,电子注电流13A得到了293 kW的峰值输出功率,最大增益56 dB,效率34.2％,3 dB带宽2.1 GHz的结果;介绍了W波段回旋行波管、回旋振荡管、Q波段回旋行波管的实验情况.