高本振中频隔离超宽带混频芯片设计

超宽带谐波混频器一般采用本振中频双工器,从本振通路引出中频信号。但是当本振频率和中频频率相近或者重叠时,难以实现本振到中频高隔离。本文采用了不同于常用谐波混频器结构,用射频中频双工器替代了本振中频双工器,从射频通路引出中频信号,设计了30~110 GHz 4次谐波混频芯片,并进行了封装实验测试。经测试,4次谐波混频器射频频率30~110 GHz,中频频率1 GHz的变频损耗小于25 dB,DC-15 GHz本振和中频端口间的隔离度可达30 dB,固定本振时中频频率DC-7 GHz变频损耗小于28 dB。因此,本设计可有效隔离频率相近的本振和中频信号,为拓宽中频带宽提供可能。     

3 mm波段宽带混频器的设计

混频器广泛应用于通信接收系统,随着微波通信系统向高频段方向发展,高频段的毫米波混频器成为了重点研究毫米波器件之一。介绍了一种结构新颖的毫米宽带混频器的设计,本振信号由矩形波导向悬置微带线引入,射频信号由矩形波导向鳍线引入,一对肖特基二极管搭在悬置微带线和鳍线之间构成了平衡混频电路,经仿真验证,设计出的毫米波宽带混频器在75~105 GHz的工作频率上,变频损耗优于12 dBm,各端口之间的隔离度也优良,且该混频器具有结构简单、易于加工等优点。     

V波段宽带混频器的设计

宽带混频器由于其工作带宽大,变频损耗低,在通信、雷达以及微波毫米波测试仪器等系统得到广泛的应用。介绍了一种V波段鳍线单平衡混频器的设计过程并给出了测试结果。从单平衡混频器的基本原理出发,阐述了鳍线单平衡混频电路和矩形波导到鳍线的过渡结构的设计。最后制作出的宽带混频器在射频频率为50～75GHz的整个V波段内,变频损耗小于10dBm,并有良好的变频损耗平坦度。     

0.7—7.7GHZ超宽带微波集成双平衡混频器

本文介绍一超宽带微波集成双平衡混频器的理论、设计方法并给出测试结果。文中采用导纳矩阵法对微带巴伦进行理论分析,给出了最佳巴伦阻抗值;为扩展中频带宽,提出了利用悬置微带线提取中频,从实验证明了新方法是可行的。最后将测试结果与国内外同类产品进行比较。该混频器在0.7～7.7GHz范围内,平均单边带变频损耗L≤10db,射频与本振端间隔离度为20dB,中频可扩展到1000MHz。     

基于六端口混频器的研究

在航天测控系统中通常对射频信号采用多级变频的方式来得到中频信号,传统的变频方式结构复杂,射频端口与本振端口具有隔离度小等缺点。针对航天系统中传统变频器的这些缺陷,设计了一个由功分器和耦合器组成无源六端口结、平方率检波器以及差分放大器组成的六端口混频器结构,其工作中心频率为2.25 GHz。首先对六端口混频器结构和变频原理进行了分析,采用ADS软件分别对六端口结和六端口混频器进行了仿真。仿真表明六端口结具有很好的隔离度和相位传输特性,六端口混频器具有变频损耗小,动态范围大以及所需本振功率低等特点。同时六端口混频器结构简单,因此用六端口混频器替代传统的混频器结构有一定的优势。     

3～40 GHz宽带双平衡混频设计与分析

双平衡混频器具有宽频带、高隔离度等优点,因而具有广阔的应用前景。设计了一种40GHz双平衡混频器,介绍了双平衡混频器设计原理和关键技术的解决方案。基波双平衡混频器利用微波薄膜混合集成电路工艺,在3～40GHz范围内实现宽频带输出,具有较低的变频损耗,并具有较好的本振-射频、本振-中频隔离度,在实际工程中可作为上、下变频器使用。     

一种宽带微带线-悬置微带线过渡电路设计

基于悬置微带电路的应用需求,设计了一种新型的宽频带微带线-悬置微带线过渡电路,过渡结构采用"V型开槽地"结构实现微带线到悬置微带线电场方向的过渡转换,并使用渐变信号线进行阻抗匹配以拓展带宽。最终的仿真结果表明:该结构在0~40 GHz的频带范围内回波损耗优于15 dB,插入损耗小于0.165 dB,并且电路性能对电路尺寸的敏感性较低。该设计将具有超低损耗的悬置线与最常用的微带线电路相结合,并且具有宽频带、插损低、易于加工、结构紧凑等优势,改善了悬置微带电路的应用范围,可以更好地同其它电路或系统进行综合应用。     

高线性低变频损耗短波超宽带混频器设计

采用双平衡场效应管管堆和巴伦设计了一款适用于短波超宽带接收机的高线性低变频损耗混频器。巴伦由射频铁氧体传输线变压器实现,插入损耗小,工作频带宽。该混频器射频输入频率为0.3~70MHz,覆盖7.8个倍频程,本振输入频率为40.755~110.455MHz,中频输出为40.455MHz。测试结果表明,混频器最佳本振功率在17dBm左右,变频损耗5dB左右,输入三阶截点高于34dBm,本振-中频隔离度大于30dB,本振-射频隔离度大于50dB。     

插入式扫频振荡器达到新的谐波水平

8350型扫频振荡器有一种新的射频插入式信号源,其型号为83592C,在2～20GHz频率范围内谐波信号含量仅为-55dBc,这个谐波抑制电平比以前的宽带微波扫描发生器(包括8350型的其它插入式单元)至少改善了15dB。 83592C型射频插入式单元在它的输出电路中附加YIG跟踪滤波器,所以可达到这样低的谐波。仔细调整这种滤波器     

宽带同轴混频器的设计

本文就研制0.01～2GHz宽带扫频信号发生器中所用的同轴混频器进行了分析和论述。文中简要分析了双平衡混频电路的特点,并论述了同轴混频器中,同轴线构成巴仑的基本原理设计方法,在同轴巴仑的设计中指出了匹配段设置的必要性及用阻抗园图进行计算的方法。最后,对实际制作的0.01～2GHz宽带同轴混频器测试情况,实用效果和与其他结构形式的宽带混频器特点比较作了简要介绍。     

CPW 馈电的高隔离度一阻带 UWB-MIMO 天线设计

针对目前超宽带多输入多输出( ultra wideband multiple-input multiple,UWB-MIMO)天线仍存在的尺寸大、端口隔离不 够高、抗干扰能力弱等缺陷,设计了一款使用共面波导馈电( coplanar waveguide feed,CPW) 馈电的小型化具有陷波特性的 UWB-MIMO 缝隙天线,通过将方形辐射贴片切角来拓宽带宽,两天线单元地板互联,并在天线单元间增加栅栏形解耦枝节来 提高天线的隔离度。 天线尺寸仅为 30 mm × 56 mm × 0. 8 mm。 此外,在方形辐射贴片上刻蚀了开口谐振环( split ring resonator,SSR)结构的 C 形槽,可滤除 WLAN 频段信号( 5. 15 ~ 5. 85 GHz)对 UWB 系统的干扰。 天线的实测结果表明,该天 线工作频段为 2. 73 ~ 10. 71 GHz,端口隔离度小于- 20 dB,包络相关系数 ECC< 0. 01。 实验结果表明该天线适用于 UWBMIMO 通信系统。     

紧凑型超宽带 MIMO 天线的研究

针对当前超宽带多输入多输出(UWB-MIMO)天线存在尺寸大、隔离度低等缺陷,设计了一款紧凑型UWB-MIMO天线,天线尺寸仅有41 mm×25 mm×1.6 mm。通过扳手形微带馈线扩宽天线的带宽,在天线的接地平面上引入锯齿形和梳状电磁带隙结构以获得较高的隔离度;加载C形枝节形成陷波以抑制X波段的下行频段对超宽带系统的干扰。实验结果表明,所设计的UWB-MIMO天线的阻抗带宽为3.1～12.0 GHz,陷波频带为7.0～7.9 GHz;在整个工作带宽内,隔离度大于20 dB。设计的UWB-MIMO天线具有良好的辐射特性、稳定的增益和较低的包络相关系数(ECC<0.006),适用于UWB-MIMO系统应用。     

FABRICATION AND CHARACTERIZATION OF FULLY EMBEDDED DIPLEXER AND BAND-PASS FILTERS FOR ORGANIC RF SOP APPLICATIONS

ABSTRACT

In this paper, fully embedded dual-band WLAN diplexer, 2.4 GHz WLAN BPF and wide-band pass filter are investigated into a multi-layered organic package substrate for low cost RF SOP (System on Package) applications. These embedded passive components were designed and analyzed by using ADS circuit simulator and CST 3D EM simulator for verifying their applicability. The fabricated diplexer and filters are the smallest one of the filters formed onto the organic substrate. The diplexer has a size of 3 mm × 2.5 mm × 0.77 mm and exhibits an insertion loss of max ?0.68 dB in 2.4 ～ 2.5 GHz band and max –3 dB in 5.15 ～ 5.32 GHz band, respectively. The 2.4 GHz BPF has a size of 2.7 mm × 2.1 mm × 0.77 mm and exhibits an insertion loss of max ?2.7 dB. The WBPF has a size of 3.2 mm × 2.5 mm × 0.77 mm and exhibits an insertion loss of ?2.65 dB. The major benefit of these embedded passive components, compared to a discrete solution, is a significant simplification and size/volume reduction of RF systems design.     

A linearized and low noise CMOS mixer with B‐type amplifier‐based sub‐harmonic balun

A low noise and high linearity down‐conversion CMOS mixer for 2.4‐GHz wireless receiver is presented in this paper. Using a sub‐harmonic balun with a simple but effective B‐type amplifier, the local oscillator frequency required for this mixer has been reduced by half, and the input local oscillator signal could be single‐ended rather than differential, which simultaneously simplifies the design of local oscillator. A distortion and noise cancelation transconductor in association with current bleeding technique is employed to improve the noise and linearity of the entire mixer under a reduced bias current without compromising the voltage gain. Fabricated in a 0.18‐µm RF CMOS technology of Global Foundries, the mixer demonstrates a voltage gain of 15.8 dB and input‐referred third‐order intercept point of 6.6 dBm with a noise figure of 2.6 dB. It consumes 7.65 mA from a 1.0‐V supply and occupies a compact area of 0.75 × 0.71 mm² including all test pads. Copyright © 2016 John Wiley & Sons, Ltd.     

A 1–6 GHz analog radio frequency power driver in 90 nm complementary metal‐oxide semiconductor technology for wireless applications

One of the most challenging subsystems for integrated radio frequency (RF) complementary metal‐oxide semiconductor (CMOS) solutions is the power amplifier. A 1–6 GHz RF power driver (RFPD) in 90 nm CMOS technology is presented, which receives signals from on‐chip RF signal chain components at ?12 dBm power levels and produces a 0 dBm signal to on‐chip or off‐chip 50 Ω loads. A unique unit cell design is developed for the RFPD to offset issues associated with very wide multi‐fingered transistors. The RF driver was fabricated as a stand‐alone sub‐circuit on a 90 nm CMOS die with other sub‐circuits. Experimental tests confirmed that the on‐chip RFPD operates up to 6 GHz and is able to drive 50 Ω loads to the desired 0 dBm power level. Spur free dynamic range exceeded 70 dB. The measured power gain was 11.6 dB at 3 GHz. The measured 1 dB compression point and input third‐order intercept point (IIP3) were ?4.7 dBm and ?0.5 dBm, respectively. Also, included are modeling, simulation, and measured results addressing issues associated with interfacing the die to a package with pinouts and the package to a printed circuit test fixture. The simulations were made through direct current (DC), alternating current (AC), and transient analysis with Cadence Analog Design Environment. The stability was also verified on the basis of phase margin simulations from extracted circuit net‐lists. Copyright © 2013 John Wiley & Sons, Ltd.     

A reconfigurable high ultimate rejection inductorless band‐pass filter by the use of N‐path passive mixers

In this paper, a band‐pass filter with a tunable bandwidth and the center frequency is introduced, which employs N‐path and N × M‐path passive mixer structures, for multiband multistandard wireless receivers. The center frequency of the proposed filter is tunable from 0.1 to 1 GHz, while its bandwidth is also adjustable from 6% to 34% of the center frequency at 100 MHz. The passband ripple is reduced by applying a Miller compensation technique, resulting in a worst‐case ripple of only 1.6 dB over the entire tuning range. An additional eight‐path filter is also utilized at the input of the circuit, which highly improves the out‐of‐band rejection of the filter as well as its out‐of‐band linearity. The noise figure and the input return loss are, respectively, better than 5 and 10 dB, and depending on the desired center frequency, the total power consumption of the proposed filter varies from 41 to 70 mW.     

采用阶梯 T 型谐振器的双陷波 UWB 滤波器

为有效抑制印度国家卫星通信C频段和X卫星频段对超宽带通信系统的干扰,提出了一种新型双陷波超宽带滤波器。该滤波器采用阶梯T型多模谐振器(multimode resonator, MMR)与缺陷地结构(defected ground structure, DGS)的交趾耦合,实现超宽带特性。采用非对称耦合线及在MMR两侧耦合分裂环谐振器的方法,分别在6.67～7.06 GHz, 7.47～7.57 GHz两个频段内产生陷波。实测结果与仿真结果吻合较好,该滤波器的通带范围为3.03～11.50 GHz, 3 dB带宽达到123%,插入损耗仅有0.87 dB,两处陷波中心频率分别在6.87 GHz和7.52 GHz,陷波深度均大于20 dB,且整体尺寸紧凑,仅有16 mm×8 mm大小。     

Duo triangle-shaped rectangular microstrip-fed patch antennas input and output parameters investigation

Conventional rectangular microstrip-fed patch antennas are initially investigated numerically within the frequency band 2.0 to 2.8 GHz for Wi-Fi applications. In order to enhance the input parameters of the underlying antennas, three prototypes are designed. A split is diagonally loaded on a conventional radiating patch to achieve a duo triangle-shaped microstrip-fed patch antenna in the first step. The conducting ground plane of the conventional and the duo triangle-shaped patches is modified to design the microstrip-fed monopole and duo triangle-shaped monopole antennas in the second and third steps, respectively, within the frequency band of 2.0 to 7.0 GHz. Concepts of voltage and current waves as well as classical electrostatics approach solutions are used to, respectively, investigate the return loss bandwidth and the electric field radiation pattern of the proposed antennas. Numerical simulations show some relevant antenna performances such as a triple-band, a −10-dB return loss bandwidth of 29% , a gain of 7.5 dB, and a calculated half power beam width of 120^° in E-plane.