2.5 dB NF 3.1-10.6 GHz CMOS UWB LNA with small group-delay variation

A 3.1-10.6 GHz ultra-wideband low-noise amplifier (UWB LNA) with excellent phase linearity property (group-delay variation is only plusmn 16.7 ps across the whole band) using standard 0.13 mum CMOS technology is reported. To achieve high and flat gain and small group-delay variation at the same time, the inductive peaking technique is adopted in the output stage for bandwidth enhancement. The UWB LNA achieved input return loss (S₁₁) of -17.5 to -33.6 dB, output return loss (S₂₂) of -14.4 to -16.3 dB, flat forward gain (S₂₂) of 7.92 plusmn 0.23 dB, and reverse isolation (S₁₂) of -25.8 to -41.9 dB over the 3.1-10.6 GHz band of interest. A state-of-the-art noise figure (NF) of 2.5 dB was achieved at 10.5 GHz.     

Bidirectional radiated circularly polarised square-ring antenna for portable RFID reader

A novel single-layer, dual-fed technique for a bidirectional radiated circularly polarised square-ring antenna operated in the UHF band is presented. The two feed ports of the square-ring radiating element are placed in orthogonal directions and connected to a feeding network with a Wilkinson power divider in the same plane. Properly adjusting the size of the capacitive coupling groundplane results in good impedance matching and circularly polarised radiation, and a broad impedance bandwidth (S₁₁ ⩽ -10 dB) of about 45.2% and a 3 dB axial-ratio bandwidth of about 8.7% were obtained.     

Reconfigurable SiGe Low-Noise Amplifiers With Variable Miller Capacitance

A new input matching method making use of shunt-shunt feedback capacitance is introduced. Based on the new input matching method, reconfigurable SiGe low-noise amplifiers (LNAs) by varying shunt-shunt feedback capacitance are proposed. Two approaches are used to vary the shunt-shunt feedback capacitance. One approach is to switch between two different bias currents while the other is to use a series combination of a switch and a capacitor. Miniaturized fully monolithic reconfigurable SiGe LNAs without emitter degenerative inductors were realized by the above two approaches. The reconfigurable SiGe LNA achieved by switching bias currents only occupies a very small area of 355 mumtimes155 mum, excluding measurement pads. This LNA achieves an input return losses (S₁₁) of -27.6 dB, a voltage gain (A _v) of 19.8 dB, and a noise figure (NF) of 3.18 dB for 2.4-GHz band when biased at a current of 3.8 mA and can be reconfigured to obtain A_v=20.4/20.3 dB, S₁₁=-47.1/-24.6 dB and NF=3.42/3.21 dB for 5.2/5.7-GHz band when bias current is switched to 3 mA. In addition, a 2.4/4.9/5.2/5.7-GHz reconfigurable SiGe LNAs for WLAN applications, whose variable shunt-shunt feedback capacitance is controlled by a switch and a capacitor, was also realized     

First demonstration of monolithic InP-based HBT amplifier with PNPactive load

An InP-based integrated HBT amplifier with PNP active load was demonstrated for the first time using complementary HBT technology (CRBT). Selective molecular beam epitaxy (MBE) regrowth was employed and a merged processing technology was developed for the monolithic integration of InP-based NPN and PNP HBTs on the same chip. The availability of PNP devices allowed design of high gain amplifiers with low power supply voltage. The measured amplifier with PNP HBT active load achieved a voltage gain of 100 with a power supply (V_CC) of 1.5 V. The corresponding voltage swing was 0.9 V to 0.2 V. The amplifier also demonstrated S₂₁ of 7.8 dB with an associated S₁₁ and S₂₂ of -9.5 dB and -8.1 dB, respectively, at 10 GHz     

0.18 μm 21-27 GHz CMOS UWB LNA with 9.3 ± 1.3 dB gain and 103.9 ± 8.1 ps group delay

A 21-27 GHz CMOS ultra-wideband low-noise amplifier (UWB LNA) with state-of-the-art phase linearity property (group delay variation is only ± 8.1 ps across the whole band) is reported for the first time. To achieve high and flat gain (S₂₁) and small group delay variation at the same time, the inductive series peaking technique was adopted in the output of each stage for bandwidth enhancement. The LNA dissipated 27 mW power and achieved input return loss (S₁₁) of 213 to 220.1 dB, output return loss (S₂₂) of 28.2 to 230.2 dB, flat S21 of 9.3 ± 1.3 dB, reverse isolation (S₁₂) of 252.7 to 273.3 dB, and noise figure of 4.9?6.1 dB over the 21-27 GHz band of interest. The measured 1 dB compression point (P_1dB) and input third-order intermodulation point (IIP3) were 214 and 24 dBm, respectively, at 24 GHz.     

Phase-coherent frequency divider with high speed-gain/power figure-of-merit

A phase-coherent transformer (PCT) enabled 22 GHz dynamic frequency divider in 0.18 mum CMOS with 16 dB power gain, 7 dB phase noise reduction and superb speed-gain/power FOM of 2times10²/pJ is demonstrated. The on-chip PCT enforces energy reverberation between the sensing/latching stages and enhances the frequency divider efficiency by eliminating the `slave' stage and the buffer amplifiers     

基于慢波基片集成波导的X波段功分器设计

针对传统基片集成波导（substrate integrated waveguide,SIW）功分器设计中宽带化和小型化不易兼顾的问题,提出了一种基于慢波SIW（slow-wave SIW, SW-SIW）的功分器. 采用微带折线构成的慢波结构单元加载于SIW金属表面上,代替传统SIW连续的金属表面,与同尺寸的SIW相比,SW-SIW的截止频率下降了40%,能够实现横向尺寸的缩减,尤其当SW-SIW达到与SIW相同的相移量时,SW-SIW所需纵向尺寸更小. 所提出的基于SW-SIW的功分器在具有较宽带宽的同时实现了器件尺寸的减小. 通过测试结果可得,该功分器在8.25～12.8 GHz频带内的反射系数|S₁₁|相似文献   

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.     

0.18 μm 3.1-10.6 GHz CMOS UWB LNA with 11.4±0.4 dB gain and 100.7± 17.4 ps group-delay

A3.1-10.6 GHz ultra-wideband low-noise amplifier (UWB LNA) with excellent phase linearity property (group-delay-variation is only plusmn17.4 ps across the whole band) using standard 0.18 mum CMOS technology is reported. To achieve high and flat gain and small group-delay-variation at the same time, the inductive peaking technique is adopted in the output stage for bandwidth enhancement. The UWB LNA dissipates 22.7 mW power and achieves input return loss (S₁₁) of -9.7 to -19.9 dB, output return loss (S22) of-8.4 to -22.5 dB, flat forward gain (S21) 11.4 plusmn0.4 dB, reverse isolation (S12) of -40 to -48 dB, and noise figure of 4.12-5.16 dB over the 3.1-10.6 GHz band of interest. A good 1 dB compression point (Pi dB) of -7.86 dBm and an input third-order intermodulation point (IIP3) of 0.72 dBm are achieved at 6.4 GHz. The chip area is only 681 x 657 mum excluding the test pads.     

A 60-dB gain, 55-dB dynamic range, 10-Gb/s broad-band SiGe HBTlimiting amplifier

A limiting amplifier IC implemented in a silicon-germanium (SiGe) heterojunction bipolar transistor technology for low-cost 10-Gb/s applications is described. The IC employs 20 dB gain limiting cells, input overload protection, split analog-digital grounds, and on-chip isolation interface with transmission lines. A gain enhancement technique has been developed for a parallel-feedback limiting cell. The limiting amplifier sensitivity is less than 3.5 mV_pp at BER=10^-9 with 2-V_pp maximum input (55-dB dynamic range). The total gain is over 60 dB, and S₂₁ bandwidth exceeds 15 GHz at 10-mV_pp input. Parameters S₁₁ and S₂₂ are better than -10 dB in the 10-GHz frequency range. The AM to PM conversion is less than 5 ps across input dynamic range. The output differential voltage can be set from 0.2 to 2 V_pp with IC power dissipation from 250 mW to 1.1 W. The chip area is 1.2×2.6 mm². A 10-Gb/s optical receiver, built with the packaged limiting amplifier, demonstrated -19.6-dBm sensitivity. The IC can be used in 10-Gb/s fiber-optic receivers requiring high sensitivity and wide input dynamic range     

Analysis, design, and optimization of InGaP-GaAs HBTmatched-impedance wide-band amplifiers with multiple feedback loops

The realization of matched impedance wide-band amplifiers fabricated by InGaP-GaAs heterojunction bipolar transistor (HBT) process is reported. The technique of multiple feedback loops was used to achieve terminal impedance matching and wide bandwidth simultaneously. The experimental results showed that a small signal gain of 16 dB and a 3-dB bandwidth of 11.6 GHz with in-band input/output return loss less than -10 dB were obtained. These values agreed well with those predicted from the analytic expressions that we derived for voltage gain, transimpedance gain, bandwidth, and input and output impedances. A general method for the determination of frequency responses of input/output return losses (or S₁₁, S₂₂) from the poles of voltage gain was proposed. The intrinsic overdamped characteristic of this amplifier was proved and emitter capacitive peaking was used to remedy this problem. The tradeoff between the input impedance matching and bandwidth was also found     

High-temperature superconducting beam forming network forcommunication system applications

This paper presents an application of the high-temperature superconductor (HTS) technology to the development of a high-performance antenna beam forming network (BFN) for communication systems. Design and measurements are made in Ku-band with a multiple power divider technique involving a cascade of 3-dB branch-line couplers. Three microstrip couplers are integrated to form a one-to-four BFN. An experimental prototype is fabricated with TlBaCaCuO thin film deposited onto LaAlO ₃ substrate. Power handling capability of related HTS components such as line, bend, and BFN are also studied together with third-order intermodulation characteristics. It is shown that theoretical prediction is consistent with experimental results, presenting insertion loss of the four output ports ranging from 6.1-6.4 dB and return loss better than 14 dB at 11.95 GHz. These preliminary results demonstrate the potential of extending such a power divider technique in designing an N-port BFN. It is also indicated that the proposed HTS BFN scheme can offer advantages compared to its conventional counterpart, namely, a significant reduction in size/weight and low power loss     

3–10-GHz Ultra-Wideband Low-Noise Amplifier Utilizing Miller Effect and Inductive Shunt–Shunt Feedback Technique

In this paper, we demonstrate an SiGe HBT ultra-wideband (UWB) low-noise amplifier (LNA), achieved by a newly proposed methodology, which takes advantage of the Miller effect for UWB input impedance matching and the inductive shunt-shunt feedback technique for bandwidth extension by pole-zero cancellation. The SiGe UWB LNA dissipates 25.8-mW power and achieves S₁₁ below -10 dB for frequencies from 3 to 14 GHz (except for a small range from 10 to 11 GHz, which is below -9 dB), flat S₂₁ of 24.6 plusmn 1.5 dB for frequencies from 3 to 11.6 GHz, noise figure of 2.5 and 5.8 dB at 3 and 10 GHz, respectively, and good phase linearity property (group-delay variation is only plusmn28 ps across the entire band). The measured 1-dB compression point (P₁ dB) and input third-order intermodulation point are -25.5 and -17 dBm, respectively, at 5.4 GHz.     

一种新型布局的圆极化微带天线阵优化设计

提出了一款高增益低副瓣新型圆极化微带天线阵。单元天线采用叠层切角圆极化微带结构,通过八边形边界布局和顺序旋转交叠组阵技术,实现了天线阵方向性图的对称性和圆极化辐射性能的最优化;馈电网络采用威尔金森功分器和最大平坦式阻抗变换器实现不等功分宽带阻抗匹配,通过改进馈电方向寻求对称结构,简化了馈电网络的设计。制作了天线阵实物并进行了测量。测试结果表明:天线在3.2~4.6 GHz频段内S₁₁<-10 dB,阻抗相对带宽36%;在3.8~4.5 GHz频段内顶点轴比小于3 dB,圆极化相对带宽17%;在4~4.4 GHz频段内天线增益均在15 dB以上,最高增益达17 dB。     

Miniaturized Microstrip Wilkinson Power Divider With Harmonic Suppression

A microstrip Wilkinson power divider with harmonic suppression and size reduction is presented in this letter. The proposed power divider not only effectively reduces its occupied area to 36.5% of the conventional design at 2.65 GHz but also has higher order harmonics suppression. From the measured results, a 29 dB suppression for the third harmonic and a 34 dB suppression for the fifth harmonic are achieved while maintaining the characteristics of a conventional Wilkinson power divider. Based on a 15 dB return-loss criteria, the measured fractional bandwidth is 48%. At an operation frequency of 2.65 GHz, the insertion losses are better than 3.4 dB, the return loss is 27 dB, and the isolation is better than 22 dB.      

Broadband single- and double-balanced resistive HEMT monolithicmixers

A double-balanced (DB) 3-18 GHz and a single-balanced (SB) 2-16 GHz resistive HEMT monolithic mixer have been successfully developed. The DB mixer consists of a AlGaAs/InGaAs HEMT quad, an active LO balun, and two passive baluns for RF and IF. At 16 dBm LO power, this mixer achieves the conversion losses of 7.5-9 dB for 4-13 GHz RF and 7.5-11 dB for 3-18 GHz RF. The SB mixer consists of a pair of AlGaAs/InGaAs HEMT's, an active LO balun, a passive IF balun and a passive RF power divider. At 16 dBm LO power, this mixer achieves the conversion losses of 8-10 dB for 4-15 GHz RF and 8-11 dB for 2-16 GHz RF. The simulated conversion losses of both mixers are very much in agreement with the measured results. Also, the DB mixer achieves a third-order input intercept (IP₃) of +19.5 to +27.5 dBm for a 7-18 GHz RF and 1 GHz IF at a LO drive of 16 dBm while the SB mixer achieves an input IP ₃ of +20 to +28.5 dBm for 2 to 16 GHz RF and 1 GHz IF at a 16 dBm LO power. The bandwidth of the RF and LO frequencies are approximately 6:1 for the DB mixer and 8:1 for the SB mixer. The DB mixer of this work is believed to be the first reported DB resistive HEMT MMIC mixer covering such a broad bandwidth     

Lithium Niobate Ridge Waveguides Fabricated by Wet Etching

The fabrication of LiNbO₃ ridge waveguides etched by a mixture of HF and HNO₃ using chromium (Cr) stripes as masks is reported. Smooth etched surfaces are obtained by adding some ethanol into the etchant. Under-etching is nearly avoided by annealing the sample with the Cr masks before the wet etching process. Low-loss monomode ridge guides with a height of up to 8 mum and a width between 4.5 and 7.0 mum are demonstrated. As an example, the propagation losses in a 6.5-mum-wide and 8-mum-high structure are 0.3 dB/cm for transverse-electric and 0.9 dB/cm for transverse-magnetic polarization, respectively, at 1.55-mum wavelength     

A Compact, ESD-Protected, SiGe BiCMOS LNA for Ultra-Wideband Applications

Two 3.65-mW, ESD-protected, BiCMOS ultra-wideband low-noise amplifiers (LNAs) for operation up to 10 GHz are presented. These common-base LNAs achieve significant savings in die area over more widely used cascoded common-emitter LNAs because they do not use an LC input matching network. A design with a shunt peaked load achieves a high S₂₁ (17-19 dB) and low noise figure (NF) (4-5 dB) across the band. A resistively loaded design exhibits a lower S₂₁ (15-16 dB) and higher NF (4.5-6 dB), but also utilizes 20% less silicon area. Both LNAs achieve a 1.5 kV ESD protection level and an acceptable S₁₁ (<-10 dB) across the band. Current source noise reduction is critical in common base topologies. Therefore, detailed noise analyses of MOS- and HBT-based current sources are provided     

Integrated metal magnetic film coupled line circulators for monolithic microwaveintegrated circuits

A new structure of integrated planar metal magnetic film coupled line (MMFCL) circulators is presented, in which a metal magnetic film is used instead of ferrite materials. Simulation was performed with HFSS based on coupled-mode theory. An insertion loss of 4 dB and isolation of -13.5 dB between S₂₁ and S₁₂ over a frequency band of 3 GHz (from 36.5 to 39.5 GHz) were realised for a three-port MMFCL circulator     

Modeling of Cascade Lasing in Dy : Chalcogenide Glass Fiber Laser With Efficient Output at 4.5 μm

The performance of a continuous-wave Dy:GeAsGaSe chalcogenide glass fiber laser operating on the ⁶H_11/2 rarr ⁶H_13/2 transition at 4.2-4.7 mum is studied using numerical modeling. A double-clad fiber geometry is assumed, with direct pumping of the ⁶H_11/2 level at 1.7 mum. It is shown that simultaneous lasing on the ⁶H_13/2 rarr ⁶H_15/2 transition serves to effectively depopulate the ⁶H_11/2 level and significantly improve the efficiency and power scalability. A slope efficiency of 0.16 is calculated when the fiber loss is 1 dB/m. For efficient operation, it is necessary to keep the fiber loss below ap5 dB/m.