具有带外抑制特性的Ka波段低功耗低噪声放大器

基于0.15μm GaAs赝配高电子迁移率晶体管(PHEMT)工艺,成功研制了一款30~34 GHz频带内具有带外抑制特性的低功耗低噪声放大器(LNA)微波单片集成电路(MMIC)。该MMIC集成了滤波器和LNA,其中滤波器采用陷波器结构,可实现较低的插入损耗和较好的带外抑制特性;LNA采用单电源和电流复用结构,实现较高的增益和较低的功耗。测试结果表明,该MMIC芯片在30~34 GHz频带内,增益大于28 dB,噪声系数小于2.8 dB,功耗小于60 mW,在17~19 GHz频带内带外抑制比小于-35 dBc。芯片尺寸为2.40 mm×1.00 mm。该LNA MMIC可应用于毫米波T/R系统中。     

基于DGS结构的超宽带带通滤波器

基于双开口-互补开环谐振器的缺陷地结构(DGS),设计了一个结构紧凑的基片集成波导(SIW)超宽带带通滤波器。通过调整蚀刻在SIW底面的双开口-互补开环谐振器,SIW表面的共面波导与腔体之间的耦合,同时在阻带获得3个传输零点,以得到较好的频率选择性和良好的带外抑制。经过仿真优化及实物制作,测试结果表明,该滤波器工作在7.2GHz,相对带宽28%,带外抑制良好,仿真与测试结果吻合。     

基于DGS 与半集总结构的新型LTCC 超宽带滤波器

设计了一款基于低温共烧陶瓷(LTCC)技术的新型超宽带(UWB,)带通滤波器.该款滤波器结合了半集总高通结构与缺陷地(DGS)结构,利用半集总结构实现截止频率为3.1GHz的高通滤波器,再结合DGS在高端产生阻带,从而实现通带为3.1～ 10.6GHz的带通滤波器,尺寸仅为3.2mm×1.6mm×1.2mm.实测结果表明:插入损耗＜1.5dB,反射损耗＜12dB,群时延＜0.8ns,带外抑制＞15dB(11.5～17GHz).测试与仿真结果较为吻合.此种LTCC滤波器结构具有尺寸小、插损小、群时延小等优点,而且结构简单,带宽和中心频率容易控制,相对带宽可做到150％以上,特别适合用于极宽带通信系统的频率选择.     

一款2.4GHzWiFi频段FBAR带通滤波器设计

该文设计了一款2.4 GHz WiFi频段(2 401~2 483 MHz)薄膜体声波谐振器(FBAR)滤波器。采用一维Mason电路模型,在ADS中搭建了阶梯形滤波器电路;在HFSS中建立了封装结构和测试电路有限元电磁模型,并在ADS中完成了联合仿真设计。通过微机电系统(MEMS)工艺制备与测试,滤波器在2 401~2 483 MHz频段的插入损耗≤2.2 dB。在2 520~2 900 MHz处,带外抑制≥40 dB,滤波器体积仅1.1 mm×0.9 mm×0.65 mm。     

一种基于模式匹配法的窄带Iris波导滤波器设计

提出了一种基于模式匹配法的窄带Iris波导滤波器设计方法,通过引入Matlab优化使滤波器设计周期缩短了约1/3。设计的窄带滤波器相对带宽小于3%,且较好的克服了毫米波频段滤波器高频端带外抑制较差的难题。测试结果表明,该带通滤波器插入损耗小于0.8 dB,驻波比小于1.2,中心频率34.86 GHz,带外抑制52 dB@36.5 GHz,已被成功应用于某毫米波雷达通信系统中。     

一种新型SIR结构LTCC带通滤波器设计与制作

采用低温共烧陶瓷(LTCC)技术及SIR结构,设计制作了一种新型LTCC带通滤波器,采用ADS和HFSS软件进行三维建模和电磁场优化仿真及测试。结果表明:该滤波器中心频率为2.46 GHz左右,3 dB带宽为2.28~2.71 GHz,带外抑制≥25 dB(偏离中心频率±500 MHz),外形尺寸为3.20 mm×1.61 mm×1.03 mm。     

超宽带四通道开关滤波器的设计

基于砷化镓(GaAs)工艺,利用ADS软件仿真设计了一款超宽带四通道开关滤波器芯片,频率覆盖了6GHz～20GHz,尺寸为仅3.2mm×2.4mm×0.1mm.该开关滤波器芯片由两个单刀四掷开关和四个带通滤波器电路组合而成.实物测试结果显示,在通带内插入损耗≤10dB,端口回波损耗≥15 dB,带外抑制达到了40dB....     

一种IPD吸收式低通滤波器的设计

为解决反射信号损害系统性能的问题,提出了一种具有高带外抑制和高带外吸收的小型化吸收式低通滤波器。该滤波器通过高通通路和低通通路实现了吸收式低通滤波器;通过抑制增益支路实现了高带外抑制。利用ADS和HFSS仿真软件对滤波器结构进行优化设计,并进行了实物的加工和测试。实测结果表明:该滤波器的3 dB截止频率为4 GHz,其带内最小插入损耗0.88 dB,通带内DC到3.5 GHz的回波损耗大于20 dB,阻带回波损耗大于10 dB,10.5 GHz处的阻带抑制大于45dB,从8 GHz到30 GHz的带外抑制大于33 dB,实测结果与仿真结果有较好的吻合。该滤波器尺寸仅为1220μm×650μm×87.71μm,相比传统PCB、LTCC工艺的滤波器,体积大大缩小,符合现代射频与微波系统小型化的发展趋势。     

5G 毫米波三频单阶 ISGW 腔体滤波器设计

本文提出了一种紧凑的三频单阶集成基片间隙波导( ISGW)腔体滤波器。 为了限定腔内模式数量,通过分析ISGW 腔模的谐振频率关系,设计了一个腔内只有三个谐振模式的 ISGW 腔体。 为了改善频段之间的带外抑制同时提高频率选择性,提出了新颖的三频单阶滤波响应耦合拓扑,然后在研究该腔体内的腔模位于四个端口处的耦合关系的基础上,设计了不同于传统输入输出端口的位置关系,其输入输出端口各有一个“U”型槽,呈 90°布局作馈电结构。 最后得到了三个通带内只有一个谐振模式的三频单阶腔体滤波器。 对该滤波器进行了建模、仿真和构造,然后利用网络分析仪测量了其端口反射传输系数。 测试结果表明,该滤波器的三个频段的中心频率分别为 f01 = 24. 25 GHz、f02 = 27. 57 GHz 和f03 = 31. 14 GHz;插入损耗(IL)分别为IL1 =1. 58 dB、IL2 = 1. 07 dB和IL3 =2. 51 dB;有限传输零点(FTZ)分别为FTZ1 =20. 55 GHz、FTZ2 = 26. 20 GHz、FTZ3 = 29. 37 GHz 和 FTZ4 = 33. 17 GHz;频段之间的带外抑制优于 13 dB。 测量结果与仿真结果之间存在一定的频移,但相对带宽优于仿真结果。 相比较传统滤波器器件,该款滤波器具有设计频段高、在毫米波频段带外抑制水平高、频率选择性强、整体体积小和质量轻等优势。     

新型高抑制波导滤波器设计

提出了一种新颖的波导带通滤波器设计。该滤波器是一个四阶广义切比雪夫滤波器,中心频率为9.93GHz,带宽为200 MHz,插损小于0.5 dB,带内回波损耗大于20 dB。谐振器为CQ结构,通过一个矩形波导膜片(一个不完全高度的导电杆),实现了交叉耦合,相比传统方法,产生一个额外的传输零点。由于在高端产生了两个零点,使得滤波器在阻带高端10.1 GHz处的带外抑制达到了35 dB以上。仿真实验证明了该设计方法能显著提高滤波器的带外抑制,对滤波器的小型化、高性能化有一定的意义。     

一种新型超宽带带通滤波器的设计

针对超宽带(UWB)系统易受无线网络信号干扰及传统的超宽带带通滤波器阻带较窄,不能有效抑制谐波的问题,提出了一种新型的UWB带通滤波器,该滤波器由两级交指梳状耦合谐振器级联组成,通过增加耦合指的个数来实现陷波特性,然后在两个交指谐振器的中间添加一个槽线锥形谐振器,使该滤波器具有抑制高次谐波特性,达到拓宽高阻带的效果,同时由于槽线谐振器的加入,陷波频段的抑制电平进一步提高.实验结果证明,所设计的滤波器既能保证3.1～10.6 GHz频段内的插入损耗小于3 dB,陷波频段为5.7～5.8 GHz,陷波频段的抑制电平高达-43 dB,同时又能拓宽高频阻带.     

Compact multilayer dual-band bandpass filter design using stepped impedance resonators

Compact dual-band bandpass filter (BPF) for the 5th generation mobile communication technology (5G) radio frequency (RF) front-end applications was presented based on multilayer stepped impedance resonators (SIRs). The multilayer dual-band SIR BPF can achieve high selectivity and four transmission zeros (TZs) near the passband edges by the quarter-wavelength tri-section SIRs. The multilayer dual-band SIR BPF is fabricated on a 3-layer FR-4 substrate with a compact dimension of 5.5 mm ×5.0 mm ×1.2 mm. The measured two passbands of themultilayer dual-band SIR BPF are 3.3 GHz -3.5 GHz and 4.8 GHz -5.0 GHz with insertion loss (IL) less than 2 dB respectively. Both measured and simulated results suggest that it is a possible candidate for the application of 5G RF front-end at sub-6 GHz frequency band.     

Analytical design of a microstrip UWB BPF with sharp rejection

This paper presents a new Ultra-WideBand (UWB) BandPass Filter (BPF) using half-wavelength (??/2) Stepped-Impedance Stub-Loaded Resonator (SISLR). Analytical equations derived by the even-odd mode analysis show the new filter has two tunable transmission zeros at both sides of the passband to provide a sharp rejection and seven transmission poles inside the passband to achieve U.S. UWB performance. For verification, a UWB BPF is designed, fabricated and measured. The measured results show that the fabricated filter has a -3 dB fractional bandwidth from 3.0 GHz to 10.9 GHz and its insertion loss less than 0.9 dB over the whole passband. Furthermore, the new filter exhibits a simple topology, sharp rejection, and deep stopband suppression.     

A Narrow Bandwidth Microstrip Band‐Pass Filter with Symmetrical Frequency Characteristics

This letter proposes a band‐pass filter (BPF) with two transmission zeros based on a combination of parallel coupling and end coupling of half‐wave transmission lines. The fabricated BPF exhibited a narrow bandwidth and two transmission zeros near the pass‐band due to the end‐coupled and shielding waveguide. At the center operation frequency of 60 GHz, the 20 dB bandwidth of the BPF is 1.0 GHz, which is almost 2% of the center operation frequency, and the insertion loss is 3.12 dB. Two transmission zeros reach approximately 40 dB at 58.5 and 62.5 GHz. The simulation results almost agree with the measured results.     

A 3.3 mW K-Band 0.18-μ m 1P6M CMOS Active Bandpass Filter Using Complementary Current-Reuse Pair

This letter presents a low-power active bandpass filter (BPF) at K-band fabricated by the standard 0.18 mum 1P6M CMOS technology. The proposed filter is evolved from the conventional half-wavelength resonator filter, using the complementary-conducting-strip transmission line (CCS TL) as the half-wavelength resonator. Furthermore, the complementary MOS cross-couple pair is proposed as a form of current-reuse scheme for achieving low-power consumption and high Q-factor simultaneously. The simulated results indicate that the Q-factor of the proposed half-wavelength resonator can be boosted from 9 to 513 at 25.65 GHz compared with the resonator enhanced by the nMOS cross-couple pair to Q-factor of merely 43 under the same power consumption. The proposed active BPF of order two occupies the chip area of 360 mum times 360 mum without contact pads. The measured results show that the center frequency of the active BPF is 22.70 GHz and a bandwidth of 1.68 GHz (7.39 %). The measured P_{1 dB} and noise figure at 22.70 GHz are -7.65 dBm and 14.05 dB, respectively. There is a 56.84 dB suppression between the fundamental tone and the second harmonic when the input power is -11.26 dBm. While showing 0 dB loss and some residual gain, the active BPF consumes 2.0 mA at 1.65 V supply voltage with maximum of 0.15 dB insertion loss and 9.96 dB return loss at pass band.     

Synthesis and design of an LPF with wide-stop band and high rejection level

In this paper, a compact microstrip lowpass filter (LPF) is designed, analyzed, simulated, and tested. The proposed design that consists of a basic part in the central section of the structure and two parts of suppression of harmonics that are inserted in the first and last sections of the basic part, have wide-stop band, high suppression factor (−38 dB attenuation level from 2.4 GHz up to 27.4 GHz), low normalized size and sharp roll-off. The proposed LPF has a −3 dB cut-off frequency of 2.4 GHz, a wide stopband bandwidth around 11th harmonic suppression and an insertion loss less than 0.1 dB at passband. This filter has been fabricated and tested and good agreement is observed between the simulated and measured results.     

A Balun-Bandpass filter with good in-band performance and wide stopband

A high performance Balun BandPass Filter (BPF) with capacitively loaded multiple coupled lines with very simple structure is proposed in this paper, this structure realizes simultaneous size reduction and superior harmonic response suppression performance in bandpass filtering meanwhile good differential performance of the Balun. The theory of this structure for unbalanced input into balanced output has been studied in this paper and a proper Balun and BPF characteristic by the symmetric feeding and skew symmetric feeding have been obtained to prove the theory. The enter frequency of the fabricated Balun-BPF is operated at 2.45 GHz with 6.93% Fractional Band Width (FBW), and this frequency is used for Bluetooth and some other communication systems. The differences between the two outputs are 180° ± 1.92° in phase and within 0.33 dB in magnitude. At f ₀, the amplitude imbalance and phase difference are within 0.25 dB and 180.86°, respectively. The measured frequency responses agree well with the simulated ones. With the theoretical analyses and practical results, it is shown that the proposed one has the advantages of simple structure, convenient analysis and good performance of both BPF and Balun.     

Miniaturized dual-band bandpass filter with good frequency selectivity using SIR and DGS

A miniaturized dual-band bandpass filter (BPF) using stepped impedance resonator (SIR) and defected ground structure (DGS) is presented. In order to get two desired passbands, two different transmission paths and source–load cross coupling have been implemented. One path is the SIR, and the other is the DGS. Meanwhile, it is easy to obtain good frequency selectivity by introducing several transmission zeros. The coupling scheme and current distributions are applied to demonstrate the flexible design approach. A dual-band BPF is designed, simulated, and fabricated to demonstrate the performance of the proposed dual-band filter. The measured results show that the fabricated dual-band BPF has two passbands centered at 2.41 and 3.52 GHz with the fractional bandwidth of 5.8 and 7.7%, respectively. The measured insertion loss is about 2 dB and 2.2 dB at the lower and upper passbands. The measured results show good agreement with the simulated ones.     

Multiband BPF with wide upper stop band using asymmetrically positioned stub loaded open loop resonators

In this paper, asymmetrically positioned stub loaded open loop resonators with pseudo interdigital coupling are used to design compact multiband planar bandpass filters. The first design pertains to a dualband BPF that operates at 3.5 GHz and 5.7 GHz. The parameters like position of stub, which quantifies the asymmetry, and length of stub are further optimised using real coded genetic algorithm to evolve a triband BPF. The evolutionary design procedure is supported with an example of triband BPF having passband at 3.5 GHz, 5.5 GHz and 6.8 GHz, respectively. The transmission line models for both filters are developed as well as fabricated prototypes are realised and tested. There is a good agreement between the measured and simulated results. The measured insertion loss at first and second band centred around 3.5 GHz and 5.7 GHz of the dual band BPF are 1.5 dB and 1.25 dB, respectively. For the triband BPF the values are 1.24 dB, 1.6 dB and 1.8 dB at 3.5, 5.5 and 6.8 GHz, respectively. The dualband design covers the WiMAX and IEEE 802.11a bands where as the triband design also covers the 6.8 GHz RFID frequency.     

Small Ultra-Wideband (UWB) Bandpass Filter With Notched Band

A compact ultra-wideband (UWB) bandpass filter (BPF) with notched band has been proposed and implemented in this letter. H-shaped slot is studied and adopted to tighten the coupling of inter-digital capacitor in order to improve the BPF's performance. Three pairs of tapered defected ground structures (DGS) are formed to assign their transmission zeros towards the out of band signal, thereby suppressing the spurious passband. Combining these two structures we obtain a small sized UWB BPF. Meander line slot is developed to reject the undesired wireless local-area network (WLAN) radio signals. An experimental UWB filter with notched band was fabricated with 35% less length as compared to an embedded open-circuited stub. The measured BPF insertion loss is less than 1.0 dB throughout the pass band of 2.8 to 10.8 GHz, the variation of group delay less than 0.20 ns in this band except for the notched band, and a wide stopband bandwidth with 20 dB attenuation up to at least 20.0 GHz.