Frequency Tunable Microstrip Patch Antenna Using RF MEMS Technology

A novel reconfigurable microstrip patch antenna is presented that is monolithically integrated with RF microelectromechanical systems (MEMS) capacitors for tuning the resonant frequency. Reconfigurability of the operating frequency of the microstrip patch antenna is achieved by loading it with a coplanar waveguide (CPW) stub on which variable MEMS capacitors are placed periodically. MEMS capacitors are implemented with surface micromachining technology, where a 1-mum thick aluminum structural layer is placed on a glass substrate with a capacitive gap of 1.5 mum. MEMS capacitors are electrostatically actuated with a low tuning voltage in the range of 0-11.9 V. The antenna resonant frequency can continuously be shifted from 16.05 GHz down to 15.75 GHz as the actuation voltage is increased from 0 to 11.9 V. These measurement results are in good agreement with the simulation results obtained with Ansoft HFSS. The radiation pattern is not affected from the bias voltage. This is the first monolithic frequency tunable microstrip patch antenna where a CPW stub loaded with MEMS capacitors is used as a variable load operating at low dc voltages     

On the gain of a reconfigurable-aperture antenna

A full-wave analysis based on the method of moments (MoM) is carried out for a reconfigurable-aperture antenna consisting of a two-dimensional (2-D) array of filamentary microstrip-dipoles interconnected by lossy microelectromechanical-system (MEMS) switches. Activation of specific MEMS switches allows the dipoles to be maintained near the halfwave-resonant length as the frequency is reduced in octave increments between 16 and 2 GHz. This keeps the real part of the dipole self-impedance much higher and the imaginary part much lower than in a dipole having a fixed length of λ/2 at 16 GHz. Hence, the array antenna gain and aperture efficiency remain much higher with frequency than in an array of fixed dipoles. Broad side aperture efficiencies of -3.9, -6.0, -9.5, and -10.6 dB are predicted for 16×16, 8×8, 4×4, and 2×2 recap dipole arrays at frequencies of 16, 8, 4, and 2 GHz, respectively, for MEMS switches having 0.5 dB insertion loss. In contrast, fixed-element λ/2-separated arrays operating at the same frequencies have predicted efficiencies of -3.9, -24.2, -45.0, and -63.0 dB, respectively     

Package‐Platformed Linear/Circular Polarization Reconfigurable Antenna Using an Integrated Silicon RF MEMS Switch

This letter presents a K‐band polarization reconfigurable antenna integrated with a silicon radio frequency MEMS switch into the form of a compact package. The proposed antenna can change its state from linear polarization (LP) to circular polarization (CP) by actuating the MEMS switch, which controls the configuration of the coupling ring slot. Low‐loss quartz is used for a radiating patch substrate and at the same time for a packaging lid by stacking it onto the MEMS substrate, which can increase the system integrity. The fabricated antenna shows broadband impedance matching and exhibits high axial ratios better than 15 dB in the LP and small axial ratios in the CP, with a minimum value of 0.002 dB at 20.8 GHz in the K‐band.     

A 60-GHz multilayer parasitic microstrip array antenna on LTCC substrate for system-on-package

This letter describes a compact and high-gain multilayer parasitic microstrip array antenna (MPMAA). The design and performance of the proposed array antenna are presented. The antenna employs three layers with a 2/spl times/2 parasitic array on each layer. The developed prototype MPMAA employs a multilayer low-temperature co-fired ceramic (LTCC) substrate that is well suited to the assembly of MMIC chips. The fabricated MPMAA achieves a 7.17 dBi absolute gain at 60 GHz including the loss derived from the feeding parts and RF probe to measure its antenna performance. The spacing of the top layer of the parasitic array constructed by 2/spl times/2 elements has a free-space wavelength of 0.36 and the chip size is 10 mm/sup 2/. The fabricated MPMAA achieves both compact and high directional gain and satisfies the requirements for a millimeter-wave system-on-package (SOP).     

Design of MEMS C-Band Microstrip Antenna Array Based on High-Resistance Silicon for Intelligent Ammunition

In recent years, microstrip antennas have been more widely applied in satellite communications, mobile phones, unmanned aerial vehicle (UAV), and weapons. A micro-electro-mechanical systems-based (MEMSbased) high-resistance silicon C-band microstrip antenna array has been designed for the intelligent ammunition. The center frequency is 4.5 GHz. A cavity has been designed in substrate to reduce the dielectric constant of silicon and high-resistance silicon has been used as the material of substrate to improve the gain of antenna. It is very easy to be manufactured by using MEMS technology because of the improved structure of the antenna. The results show that the gain of the antenna is 8 dB and voltage standing wave ratio (VSWR) is less than 2 by the analysis and simulation in high frequency structure simulator (HFSS).     

新型Ku波段基片集成波导缝隙阵列天线设计

介绍了基片集成波导缝隙天线的相关理论,以及宽边基片集成波导缝隙驻波阵的设计方法。首先,根据指标要求,利用HFSS电磁仿真软件来获取缝隙初始导纳参数;然后,使用Matlab软件进行数据拟合;最终,得到缝隙电导与缝隙偏置的数学函数。采用该方法设计了中心频率为15. 9 GHz 的4 元等幅同相的驻波直线阵,仿真得到在15. 8 GHz ~16 GHz 频段内驻波比小于1. 88。     

A Fully Differential Monolithic LNA With On-Chip Antenna for a Short Range Wireless Receiver

This letter presents the smallest reported 5 GHz receiver chip (1.3 mm²) with an on-chip antenna in standard 0.13 mum CMOS process. The miniaturization is achieved by placing the circuits inside a meandered antenna. The on-chip antenna is conjugately matched to the low noise amplifier (LNA) over a wide frequency range. The design methodology for co-design of the on-chip antenna and LNA is described. The LNA is completely differential, consumes only 8 mW of power and provides a gain of 21 dB. Design tradeoffs and measurement challenges are given.     

一种新型宽带印制天线

本文给出了一种新型双偶极子型宽带印制天线,并设计出相应的类平行宽边耦合双线双面馈电结构。采用矩量法求解积分方程进行理论分析,由此设计出一种新型宽带印制天线,并进行实验测试。理论分析表明：在相同的基片上,双偶极子型印制天线比普通微带振子天线的带宽宽得多;同时实测结果表明：在0.8mm的介质基片上,工作于中心频率2GHz的该新型天线带宽可达23％（VSWR＜2.0）,增益达4.3dBi。该宽带天线为平面印制结构,易于与电路集成,亦可做为天线阵元,成本低,性能好。     

A Dual-Polarized Planar-Array Antenna for S-Band and X-Band Airborne Applications

A new dual-frequency dual-polarized array antenna for airborne applications is presented in this paper. Two planar arrays with thin substrates (R/T Duroid 5880 substrate, with εr = 2.2 and a thickness of 0.13 mm) are integrated to provide simultaneous operation at S band (3 GHz) and X band (10 GHz). Each 3 GHz antenna element is a large rectangular ring-resonator antenna, and has a 9.5 dBi gain that is about 3 dB higher than the gain of an ordinary ring antenna. The 10 GHz antenna elements are circular patches. They are combined to form the array with a gain of 18.3 dBi, using a series-fed structure to save the space of the feeding line network. The ultra-thin array can be easily placed on an aircraft's fuselage, due to its lightweight and conformal structure. It will be useful for wireless communication, radar, remote sensing, and surveillance applications.     

A 77-GHz Phased-Array Transceiver With On-Chip Antennas in Silicon: Receiver and Antennas

In this paper, we present the receiver and the on-chip antenna sections of a fully integrated 77-GHz four-element phased-array transceiver with on-chip antennas in silicon. The receiver section of the chip includes the complete down-conversion path comprising low-noise amplifier (LNA), frequency synthesizer, phase rotators, combining amplifiers, and on-chip dipole antennas. The signal combining is performed using a novel distributed active combining amplifier at an IF of 26 GHz. In the LO path, the output of the 52-GHz VCO is routed to different elements and can be phase shifted locally by the phase rotators. A silicon lens on the backside is used to reduce the loss due to the surface-wave power of the silicon substrate. Our measurements show a single-element LNA gain of 23 dB and a noise figure of 6.0dB. Each of the four receive paths has a gain of 37 dB and a noise figure of 8.0 dB. Each on-chip antenna has a gain of +2 dBi     

A Transceiver Front-End for Ultra-Wide-Band Applications

An integrated pulse based ultra-wide-band (UWB) transceiver front-end is presented in this paper. The pulse generator produces Gaussian modulated pulses satisfying Federal Communication Commission spectral mask with possibility for binary-phase shift keying modulation. The generated pulses have a bandwidth of 2 GHz from 3.1 to 5.1 GHz. The receiver front-end consists of an UWB low-noise amplifier (LNA). The transmit and receive paths are chosen by a transmit/receive (T/R) switch. The pulse generator, T/R switch and the LNA are integrated on a single chip and fabricated using 0.25-mum SiGe:C BiCMOS technology. The integrated circuit components are designed fully differential. The off-chip antenna and bandpass filter are single ended and connected to the T/R switch through a hybrid coupler     

应用于毫米波无线接收系统的高集成化LTCC AIP设计

介绍了一种基于低温共烧陶瓷工艺的新型高度集成毫米波无源接收前端,该前端由阵列天线、馈电网络和带通滤波器构成.上述无源器件以天线集成封装方式经过一体化设计,并应用于毫米波无线系统.首先,设计了2×2线极化空气腔阵列天线,通过采用新颖的内埋空气腔体结构,使天线最大增益提高了2.9 dB.其次,将具有双层谐振结构的三阶小型化发卡型带通滤波器和天线馈电网络进行一体化设计.该滤波器测试结果显示:插入损耗为1.9dB,3 dB相对带宽为8.1％(中心频率为34 GHz).最后将上述天线和滤波网络进行一体化设计,实现了三维无线接收前端.在集成结构中,通过采用金属柱栅栏抑制了寄生模式.测试结果显示天线最大增益可达14.3dB,通过集成滤波馈电网络,其阻抗带宽为2.8 GHz.该新型一体化集成前端系统具有良好的射频性能,可作为全集成无源前端应用于Ka波段无线系统中.     

Reconfigurable dual-band antenna with high frequency ratio (1.6:1) using MEMS switches

A reconfigurable patch antenna integrated by using RF-mircoelectro-mechanical system (MEMS) switches is presented. The proposed antenna radiates a right-hand circularly polarised wave at the selected dual frequencies (4.8 and 7.6 GHz) with a high frequency ratio (1.6:1). The switches are incorporated into the diagonally fed square patch for controlling the operation frequencies. The proposed antenna satisfies the 3 dB axial ratio criterion and has gain between 5-6 dBi at both operating frequencies.     

W波段宽带SIW背腔缝隙天线

W波段（75~110 GHz）的电磁波大气吸收率低、波长短、可用频带宽,在雷达、通信等领域应用广泛.文章设计了一种W波段基片集成波导（substrate integrated waveguide,SIW）背腔缝隙天线,-10 dB的阻抗带宽达到28.6%（78.93~105.24 GHz）,覆盖了W波段75%的频带范围.天线采用双层基片结构.上层为SIW谐振腔及四条辐射缝隙构成的谐振辐射单元,谐振腔内同时存在TM₁₃₀与TM₃₁₀混合模、TM₃₂₀模以及TM₃₃₀模三种高次模,和辐射缝隙一起形成多谐特性,实现带宽拓展;底层为通过耦合缝隙馈电的集成波导,易于扩展成平面网络,构建高增益背腔缝隙天线阵列.该天线频带宽、交叉极化低、剖面低、易于与平面微波电路集成、加工成本低,具有良好的应用前景.     

基片集成波导全向滤波天线多天线阵列

设计、制作并测量了工作在Ku波段的、可用于频分复用(FDD)无线通信系统的基片集成波导缝隙辐射全向滤波天线及其多输入多输出(MIMO)天线阵列。滤波天线是将射频滤波器和天线辐射部分进行一体化、联合设计,以减少射频前端滤波器与天线间的连接所引入的插入损耗。经过仿真、制作、测量和比较,得出结论:独立全向滤波天线保持了辐射部分的全向辐射特性,同时能很好地抑制带外杂散信号,使输入端反射系数的过渡带变得陡峭。工作在13.6GHz和14.4GHz、带宽为100MHz的相邻频率的全向滤波天线隔离性能良好,可用于频分复用系统的收、发信道。多输入多输出天线阵列中的单个全向滤波天线辐射特性基本保持不变。     

A 220 GHz Single-Chip Receiver MMIC With Integrated Antenna

This letter presents the design and characterization of a 220 GHz microstrip single-chip receiver monolithic microwave integrated circuit (MMIC) with an integrated antenna in a 0.1 mum GaAs metamorphic high electron mobility transistor technology. The receiver MMIC consists of a novel slot-square substrate lens feed antenna, a three-stage low noise amplifier, and a sub-harmonically pumped resistive mixer. The receiver MMIC is mounted on a 12 mm silicon substrate lens which focuses the radiation from the calibration loads to the on-chip antenna through an opening in the backside metallization of the MMIC. The double sideband noise figure of this quasioptical receiver is as low as 8.4 dB (1750 K) at 220 GHz including the losses in the antenna and in the lens. To the best of the authors' knowledge, this work demonstrates the highest integration level versus operating frequency for a MMIC ever published, regardless of technology.     

Planar millimeter-wave antennas using SiNx-membranes onGaAs

Planar aperture coupled microstrip antennas for 77 GHz are demonstrated for the first time. As far as possible standard GaAs monolithic microwave/millimeter-wave integrated circuit (MMIC) technology is used to realize the antennas. The antenna patches are suspended on a thin dielectric SiN_x membrane on GaAs substrate. Therefore a novel plasma-enhanced chemical vapor deposition (PECVD) process step for the fabrication of the membranes is developed and described. The single antenna patches are coupled to a microstrip line through an aperture in the ground metallization. The method of moments in spectral domain is applied to design the patches. The feed network of a 3×1 antenna array for homogeneous excitation is simulated and optimized with a microwave design system (MDS). From reflection measurements the operation frequency of this triple patch antenna is determined to be 77.6 GHz. The farfield antenna characteristics are measured in an anechoic chamber, showing good agreement between simulated and measured results and a co- to cross-polarization isolation better than 30 dB     

A New Compact Microstrip Integrated E-Array Patch Antenna with High Gain and High Aperture Efficiency

This paper describes a new compact single-feed, single-layer microstrip E-shaped patch antenna. It is an integrated array antenna and it is designed for a frequency range around 2.45 GHz ISM band. It is a symmetrical antenna suitably designed for WLAN application. This prototype was fabricated on a FR4 substrate with a relative permittivity of 4.7 and about 0.8 mm thickness. The aperture efficiency and gain of about 72 % and 6.7 dBi was obtained. It can be achieved by numerical algorithms for electromagnetic solutions like finite element method (FEM) and the method of moments (MOM) by using electromagnetic simulation software. For validation purpose CAD FEKO 6.1 suite is used. The bandwidth and gain achieved in the array antenna is 15 % greater than the single patch antenna.     

Broadband high-efficiency circularly polarized active antenna and array for RF front-end application

This paper presents a broadband high-efficiency circularly polarized (CP) active integrated antenna, and a broadband CP active array at 2 GHz. To realize the broadband CP antenna, a circular patch is aperture coupled by crossed slots in the ground plane, which are fed by an L-shaped microstrip feed line below the ground. The antenna is designed to serve the functions of both a radiator and a harmonics-terminated load for class-E high-efficiency power-amplifier (PA) integration. The broadband CP active antenna is realized by directly integrating the broadband CP antenna with the class-E PA. It achieves a 9% bandwidth (1.84-2.01 GHz) for axial ratio (AR) below 3 dB, and a 12% bandwidth for power-added efficiency (PAE) over 60%. To form the broadband CP active array, four active antenna elements are sequentially rotated, and each element is directly integrated with broadband class-E PA. A low-cost printed-circuit-board technology is employed in fabrication and a pseudomorphic high electron-mobility transistor is used. A peak drain efficiency of 71.5% for the class-E amplifier is measured at 1.95 GHz. The active array achieves a peak-effective radiated power of 39.7 dBm, and PAE is over 50% within a 22.6% bandwidth (1.72-2.16 GHz). The AR is below 3 dB over a 27% bandwidth (1.72-2.26 GHz).     

3-D-integrated RF and millimeter-wave functions and modules using liquid crystal polymer (LCP) system-on-package technology

Electronics packaging evolution involves system, technology, and material considerations. In this paper, we present a novel three-dimensional (3-D) integration approach for system-on-package (SOP)-based solutions for wireless communication applications. This concept is proposed for the 3-D integration of RF and millimeter (mm) wave embedded functions in front-end modules by means of stacking substrates using liquid crystal polymer (LCP) multilayer and /spl mu/BGA technologies. Characterization and modeling of high-Q RF inductors using LCP is described. A single-input-single-output (SISO) dual-band filter operating at ISM 2.4-2.5 GHz and UNII 5.15-5.85 GHz frequency bands, two dual-polarization 2/spl times/1 antenna arrays operating at 14 and 35 GHz, and a WLAN IEEE 802.11a-compliant compact module (volume of 75/spl times/35/spl times/0.2 mm/sup 3/) have been fabricated on LCP substrate, showing the great potential of the SOP approach for 3-D-integrated RF and mm wave functions and modules.