Novel 53/106 GHz Dual-Band MMW LC Oscillator Implemented in SiGe BiCMOS Technology

In this Paper, we present a fully integrated millimeter wave LC voltage-controlled oscillator (VCO), which employs a novel topology, operating at dual-band frequency of 53.22 GHz-band and 106.44 GHz-band. The low-phase noise performance of –107.3 dBc/Hz and –106.1 dBc/Hz at the offset frequency of 600 kHz, –111.8 dBc/Hz and –110.6 dBc/Hz at the offset frequency of 1 MHz around 53.22 GHz and 106.44 GHz are achieved using IBM BiCMOS-6HP technology, respectively. Two tuning ranges, of 52.7 - 53.8 GHz and 105.4 - 107.6 GHz for the proposed LC VCO are obtained. The output voltage swing of this VCO is around 1.8 V_p-p at the operation frequency of 53.22 GHz and 0.45 V_p-p at 106.44 GHz; the total power consumption is about 16.5 mW. To our knowledge, this is the first oscillator which operates at dual-band frequency above 50 GHz with the best preformance.     

L波段ESR谱仪用微波源和腔

叙述了L波段压控振荡源和谐振腔的结构和性能.振荡器的振荡频率可在0.9-1.07GHz范围变更,输出功率大于10mW.附有锯齿波产生器,能在扫频方式工作.样品腔为方柱裂缝腔,插入圆柱形样品时,频率改变较小.腔输入为磁耦合,改变线圈与腔之间的距离可以改变耦合度.     

The digital predistortion of non-linear frequency modulation of voltage-controlling-oscillator in MM-band

The reason and rectification method of the non-linear frequency modulation of voltage-controlling-oscillator in millimeter-wave band have been presented in this paper. The digital predistortion for the controlling signal of the varactor in VCO possesses high rectification sensitivity, simple circuit and convenient adjustment. The method can be used in mm-wave and microwave VCOs that are fabricated by all kinds' transmission lines, and can eliminate the dispersion of FM characteristic in VCOs that are usually caused by the machining deviation and the inconsistent parameters of semiconductors. The digital predistortion technique has been applied in NRD-guide VCO in Ka-band, which main performances are: f0 = 36.30648GHz, the frequency-stability reaches 2.26×10^–5, the maximum frequency-deviation is 150MHz, the linear-FM error is less than 5%.     

An estimation of S/N degradation at millimeter waves during rain events

The use of Ka Band (20/30 GHz) for future satellite communications has been addressed. The exploitation of Ka band with a bandwidth of 2500 MHz seems to represent the largest significant achievement in satellite communications potential, so far. The problems associated with the use of this frequency band such as attenuation and receiver noise temperature (floor) variation with rain has been addressed. The receiver noise floor variation with rain has so far been ignored. Therefore, in view of propagation and noise study over this Ka Band, both signal attenuation and receiver noise floor variations with rain rate are estimated using dual frequency radiometers operating at 22.235 and 31.4 GHz over a tropical station, Calcutta, India.     

Development of Broad Band VCO at Ka-Band

A broad band VCO has been developed at Ka-band for FMCW Radar applications. To achieve a wide range of frequency variation, VCO has been designed in series configuration. Design steps have been presented. VCO exhibits a tuning range of 600 MHz with the power output of 50 mw, when the controlled varactor voltage varies from 7.5 volts to 15 volts. Frequency drift with temperature has been contained within 30 MHz using a proportionally controlled DC heater module over the temperature range of 0°C to +55°C. Phase Noise of the oscillator measured at the mid and extreme frequencies is about -70 dBc/kHz at 10 kHz away from the carrier. The experimental circuit and measured performance is also presented.     

HL-2A 装置上的快扫Q 波段微波反射系统研制

介绍了在HL-2A 装置上发展的一套快速扫频的Q 波段外差微波反射系统,用于高时空分辨测量等离子体边缘到约束区的电子密度分布。该系统采用外差式连续波扫频调制技术(VCO),由外部任意波电压控制,工作频率为33~50GHz,全波段扫频周期达到6μs。在台面标定中发展了VCO 源的动态标定技术,并解决了微波源及器件的非线性响应、波导的色散特性等因素造成差频频率动态范围过大的问题,使反射面固定时系统输出的差频为定频信号,有利于降低噪声干扰和数据处理。同时发展了直接相位处理技术,实现快速的电子密度分布反演。实验中用该微波反射系统测得了L 模、H 模等不同等离子体放电条件下的电子密度分布,观测ELM 爆发前后台基区的形成与垮塌过程。     

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介绍了在HL-2A装置上发展的一套快速扫频的Q波段外差微波反射系统,用于高时空分辨测量等离子体边缘到约束区的电子密度分布。该系统采用外差式连续波扫频调制技术(VCO),由外部任意波电压控制,工作频率为33~50GHz,全波段扫频周期达到6μs。在台面标定中发展了 VCO 源的动态标定技术,并解决了微波源及器件的非线性响应、波导的色散特性等因素造成差频频率动态范围过大的问题,使反射面固定时系统输出的差频为定频信号,有利于降低噪声干扰和数据处理。同时发展了直接相位处理技术,实现快速的电子密度分布反演。实验中用该微波反射系统测得了L模、H模等不同等离子体放电条件下的电子密度分布,观测ELM爆发前后台基区的形成与垮塌过程。     

具有双陷波特性的超宽带天线设计

设计了一款基于共面波导馈电的小型化具有双陷波特性的超宽带天线,该天线的带宽在3～14 GHz内,电压驻波比(VSWR)小于2。在辐射贴片上通过开L型和半圆环缝隙实现了在3.3～3.7 GHz和5.150～5.825 GHz的双频段的陷波特性,抑制了802.16无线城域网和无线局域网对超宽带系统的干扰,在整个工作频段具有稳定的增益和良好的全向性。通过对天线模型进行加工制作并测量,测试结果表明:天线的带宽是3～14 GHz,在3.3～3.7 GHz和5.15～5.825 GHz频段内VSWR大于4,实现了天线的双陷波特性。该天线尺寸小、结构紧凑的特点,适合现代的无线通信系统。     

Tunable microwave photonics filter with dual pass-band based on PM-FBG and PS-FBG

In this paper, a dual pass-band microwave photonics filter with simple, commercial structure is proposed and demonstrated. The key devices are the specially designed polarization maintaining fiber Bragg grating and the phase shift fiber Bragg grating. They are employed to extract out two orthogonally polarized sidebands and remove the undesired sideband, respectively. The simulation results show that without any extra operations or electrical processing, the dual pass-band can be achieved with the two central frequencies of 3.5 GHz and 8 GHz when the frequency spacing between the two orthogonally polarized sidebands is 12 GHz, their 3-dB bandwidth are about 500 MHz. The central frequencies of the two pass-bands can be simply tuned by adjusting the frequency spacing in a range of 4 GHz. In addition, the spurious free dynamic ranges for the two pass-bands are 75.71 dB Hz^2/3 and 70.17 dB Hz^2/3 respectively. Finally, a brief experiment is also carried out to demonstrate the feasibility.     

The Development of a Dual Channel SIS Receiver of Trao Telescope

We developed a low noise dual channel receiver with 100GHz and 150GHz band, which is used to make the simultaneous observation with two bands. The SIS mixers are used in both bands. The constructed dewar for the receiver has a performance with a vacuum of 10^–8torr and a temperature of 4.2K. The receiver noise temperature is 50K(DSB) for 100GHz band and 80K(DSB) for 150GHz band, respectively. In order to achieve the simultaneous observations, the quasioptical system is precisely designed, and also evaluated by measurements in the laboratory. The relative pointing offset between two bands is 3. We have observed the various sources using the receiver since October 1998.     

Phoxonic crystals and cavity optomechanics

Phoxonic crystals are dual phononic/photonic crystals exhibiting simultaneously band gaps for both types of excitations. Therefore, they have the ability to confine phonons and photons in the same cavity and in turn allow the enhancement of their interaction. In this paper, we review some of our theoretical works on cavity optomechanical interactions in different types of phoxonic crystals, including two-dimensional, slab, and nanobeam structures. Two mechanisms are behind the phonon–photon interaction, namely the photoelastic and the moving interface effects. Coupling rates of a few MHz are obtained with high-frequency phonons of a few GHz. Finally, we give some preliminary results about the optomechanical interaction when a metallic nanoparticle is introduced into the cavity, giving rise to coupled photon–plasmon modes or, in the case of very small particles, to an enhancement of the electric field at the position of the particle.     

超宽带Cassegrain双反射面天线研究

 为了减小馈线损耗和方便天线旋转，设计了超宽带Cassegrain双反射面天线系统。采用FEKO数值模拟软件在0.2~1.5 GHz频率范围内模拟了不同副反射面直径的4.5 m双反射面天线(焦径比为0.4)的辐射增益，并与相同口径和焦径比的前馈式反射面天线进行了比较。模拟结果表明:当双曲副反射面直径为70 cm，焦距为22.5 cm时，在0.2~1.0 GHz频率范围内，双反射面天线增益比前馈式抛物面天线高1～2 dB；在1.1～1.5 GHz频率范围内，双反射面天线增益比前馈式抛物面天线小1～2 dB。选择直径为70 cm、焦距为22.5 cm的双曲副面与TEM喇叭和4.5 m抛物面组成双反射面天线系统，分别用960 ps和3 ns脉宽的单极脉冲源对天线进行了实验研究。实验结果表明:用960 ps和3 ns脉宽的单极脉冲激励，Cassegrain双反射面天线在70 m轴上远场辐射场波形峰峰值分别为前馈式反射面天线的158%和162%。     

The development of nonradiative dielectric waveguide transmitting front-end in Ka-band

The operating theory,design method and experimental results of the nonradiative dielectric waveguide (NRD-guide) transmitting front-end in millimeter wave band are related in details in this paper. As a kind of dielectric waveguide,the NRD-guide possesses fine transmission performances, and it can be used to fabricate the millimeter wave hyterodyne integrated circuits. The two kinds NRD-guide transmitting front-ends substantiated in the paper, the voltage controlling oscillator(VCO) and twin-Gunn-diode power-combiner,have very similar structures to each other and possess compact sizes, fine machinery and electric performances.For the VCO front-end in Ka-band, the frequency modulation band is greater than 150MHz, the output power is larger than 20mW.For the power-combiner, the output power is larger than 40mW,the combination efficiency is better than 90%,the frequency stabilization reaches 1.68×10^–5. Combined with the receiving front-end reported before,the transmitter and receiver can be composed to a dielectric waveguide R/T module to be applied in some millimeter wave sub-systems.     

220-320 GHz Harmonic Mixer for a Full Band Sweep Vector Network Analyzer

This paper presents the design and characterization of a fixed tuned 220-320 GHz harmonic mixer employing commercial Schottky beam lead diodes in an antiparallel configuration. A diplexer provides distinct ports and matching for the subharmonic LO (26-40GHz) and the IF (20 MHz). The conversion loss was measured using a Gunn + tripler or quadrupler source calibrated with an absolute bolometer. We have built a 220-320 GHz full band sweep Vector Network Analyzer (VNA) using two WR3 waveguide couplers and three identical harmonic mixers (transmitter, reference, and receiver) pumped by two synthesizers (13-20GHz) followed by active doublers. The available dynamic range is 60 dBc/Hz over most of the band.     

W-band 1/3 frequency dividers

In this article the theoretical and experimental performances of a Gunn harmonically synchronized frequency divider are presented. The results show that such a divider has a 96-32GHz division, with 15-mW output power over the operating band greater than 1400MHz at 10-mW input power level.     

窄带高温超导滤波器的研制

介绍了S波段窄带高温超导滤波器的设计过程,采用仿真建模和拓扑结构优化关键技术,在不需调谐的情况下,研制成功中心频率2.1GHz,带宽6MHz,群延时起伏在4.3MHz(71.7%带宽)内达到了18.321ns,插入损耗小于0.5dB,带边陡度大于17dB/MHz,驻波比优于1.5的高温超导滤波器,有利于器件的工程化应用。     

过模波导器件的迭代设计方法

从模式保留和转换的角度, 过模波导器件可分为模式转换器、模式保留器和模式综合器. 传统方法只解决其中一种器件的设计或者对器件的某个指标进行改进. 本文在深入分析耦合波理论之后, 提出了过模波导器件的迭代设计方法, 从原理上解决了过模波导器件的设计问题. 该方法能够统一设计三类过模波导器件, 通过添加不同的结构控制方法, 可得到转换效率更高、带宽更宽、结构更紧凑、满足不同工程需求的器件, 而且还能有效设计一些新型器件. 给出了两个设计实例: 双频TM₀₁–TE₁₁模式变换器和光壁馈源喇叭. 双频TM₀₁–TE₁₁模式变换器的两个工作频点为8.75 GHz和10.3 GHz, 波导半径为16 mm, 在两个频点转换效率为99%以上. 光壁馈源喇叭实现TE₁₁模式向高斯束的转换. CST仿真结果验证了这两个器件设计的正确性和有效性. 关键词： 耦合波理论 模式转换器 模式过渡器 迭代法     

Electromagnetic absorption of SRR based double-inverse E-Shaped metamaterial for DCS,EESC, 5G,and WiMAX applications

Herein, a novel double-inverse E-structured resonator metamaterial (MTM) surrounded by split-ring resonators (SRRs) is introduced and proposed. The proposed MTM has working frequency ranges of 1.62 – 1.79 GHz, 2.08 – 2.21 GHz, 4.39 – 4.99 GHz, and 5.65 – 6.09 GHz. In addition, the proposed MTM can be applied in digital cellular system uplinks (DCS) (1.736 GHz), earth exploration-satellite communication (EESC) (2.148 GHz), lower band 5G (4.8 GHz), and WiMAX (5.89 GHz) applications. The electromagnetic radiation reduction performance of the proposed MTM is investigated at 900 MHz and 1800 MHz of GSM cellular bands. The Finite Integration Technique (FIT) based on high-frequency electromagnetic software is utilised for the development of design along with a detailed investigation of the MTM properties. The proposed MTM is formed by developing a double-inverse E-structure in the middle surrounded by SRRs. The resonator structure with SRRs is implemented on an epoxy resin FR4 substrate, which has a compact size of 11.11 × 11.11 mm². The unit cell has a high effective medium ratio of 14.82. Furthermore, the developed MTM shows a negative refractive index region from 3.124 to 6.98 GHz and double-negative region from 3.94 to 4.57 GHz, 5.26 to 5.49 GHz, and 6.29 to 6.88 GHz. In addition, SAR evaluation is also performed to test the competence of utilising the proposed MTM on modern mobile phones. The MTM has an electromagnetic absorption rate of about 44% and 43% at 900 MHz and 1800 MHz, respectively, for 1g whereas about 43% and 44% at 900 MHz and 1800 MHz, respectively, for 10g. Thus, the performance and characteristics of the developed MTM can be utilised for the above-mentioned applications.     

X波段低温低噪声放大器的研制

介绍了X波段低温低噪声放大器的设计和实验结果。该放大器采用HEMT器件三级级联,频率范围为8 500MHz~8 850 MHz,在环境温度大约20K的环境下,噪声温度小于11K,输入输出回波损耗小于-25dB,功耗小于25mW,0~40GHz内无条件稳定。     

Two-frequency quasi-optical radiospectrometer for substance investigations

In this paper two-frequency radiospectrometer is described: frequency of ESR is n _e =(120 GHz – 150 GHz); frequency of the nuclear magnetic resonance (NMR) is n _n =(180 MHz – 200 MHz).Radiospectrometer is operates in the temperature band T=(4.2 K 1.7 K) and in the magnetic field band H=5 T.