A Broad-Band Low-Noise Schottky Diode Full-Height Waveguide Mixer from 80 to 115 GHz

The RF matching problem in the input circuit of the mm-wavelength whisker contacted Schottky diode mixer is studied. The experimental results, obtained on the 3mm wavelength mixer mounts in the broad band of frequencies from 80 to 115 GHz are presented. It is shown that advantage in the receiver noise temperature may be realized by the use of a full-height instead of 1/4-reduced-height waveguide because of reduction loss in the mixer input circuit even beginning from the 3mm-wavelength. With a full-height waveguide mixer the double sideband (DSB) receiver noise temperature is 300 divided by 350K over the 85 to 110 GHz band. Input bandwidth of the fullheight waveguide mixer (cap delta f _S/f _SO greater than 30%) is equal to 1/2-and close to 1/4-reduced-height waveguide mixers.     

A 75 GHz to 115 GHz quasi-optical amplifier

A wideband quasi-optical amplifier employing two pyramidal back-to-back horns has been developed. Using a four-stage W-band low noise amplifier (LNA) designed and fabricated by Martin Marietta Laboratories, the quasi-optical amplifier gives a system gain greater than 11 dB from 86 GHz to 113 GHz without any low frequency oscillations. A peak system gain of 15.5 dB is measured at 102 GHz, and the measured noise figure of the system is 7.4 dB at 94 GHz. The quasi-optical amplifier design maintains the same polarization of the received and transmitted signal, provides better than -40 dB isolation, and can be fabricated monolithically at millimeter-wave frequencies     

大功率单路和功率合成式100~115GHz 肖特基平衡式二倍频器

研究了基于肖特基二极管的单路和功率合成式110 GHz大功率平衡式二倍频器。单路倍频器电路具有33%的峰值测试效率,且其工作带宽超过13.6%。另外,采用了不同的双路合成结构来实现两种不同的合成式110 GHz倍频器。该功率合成式倍频器在两只127 μm 厚的 ALN 基片上焊接了四个分立的肖特基二极管。在800 mW的驱动功率下,两种合成式倍频器都测得了大于200 mW的输出功率,证明了利用该合成式倍频结构可实现更高输出功率。     

A 492 GHz Submillimeter-Wave Receiver

A 492 GHz submillimeter receiver was designed for application to the POrtable Submillimeter Telescope (POST). The receiver includes a Schottky diode mixer, a phase-locked Gunn oscillator at 82.3 GHz coupled with multipliers (×2×3), and low-noise amplifiers. In this paper, the system configuration and performance will be introduced.     

30GHz单片接收机

已经研制成功30GHz接收机用的几种单片集成电路.低噪声放大器芯片在14dB增益时噪声系数为7.dB,中频放大器在30dB控制范围内,增益为13dB.混频器和移相器变频损耗和插入损耗分别为10.5dB和1.6dB.     

Pumped Schottky diodes with noise temperatures of less than 100 K at 115 GHz

New Schottky-barrier diodes, with an epitaxial layer thickness of < 1000 ? and doping 2.5×1016 cm?3, yield a mixer noise temperature of 98 K at 115 GHz. The diodes have a diameter of 1.8 ?m, and show repeatable performance. Measurements indicate negligible capacitance variation to at least +0.2 V. The noise temperature is competitive with values reported for Josephson and quasiparticle junctions.     

A Broad-Band Second-Harmonic Mixer Covering 76-106 GHz

A broad-band second-harmonic millimeter-wave mixer has been constructed. The circuit consists of a single unencapsulated Schottky-barrier diode and embedding network which includes a wave absorber in the IF output terminal. The conversion loss of the mixer is 14.6/spl plusmn/0.9 dB over a frequency range of 76-106 GHz. The mixer is pumped by a Iocal oscillator that is tuned over the range of 37.15-52.15 GHz. The IF is kept constant at 1.7 GHz. The new mixer looks attractive for use in broad-band millimeter-wave measuring equipment, such as spectrum analyzers.     

The Measured and Computed Performance of a 140--220 GHz Schottky Diode Mixer

In this paper, we compare the measured and theoretical performance of a room-temperature single-ended Schottky diode mixer in the WR-5 (140-220-GHz) waveguide band. Using the computer program GISSMIX, combined with measurements made on a 100X scale model of the WR-5 mixer, we have been able to predict the millimeter-wave mixer performance over a wide tuning range with unprecedented accuracy. In addition we have examined the sensitivity of the mixer performance to various diode and mount characteristics. Our rneasured conversion loss and mixer noise temperature, single sideband, are 5.7 dB and 750 K at 180 GHz, and 5.7 dB and 500 K at 150 GHz, which we believe to be the best reported for a room-temperature mixer at these frequencies.     

A broadband 800 GHz Schottky balanced doubler

A broadband planar Schottky balanced doubler at 800 GHz has been designed and built. The design utilizes two Schottky diodes in a balanced configuration on a 12 μm thick gallium arsenide (GaAs) substrate as a supporting frame. This broadband doubler (designed for 735 GHz to 850 GHz) uses a split waveguide block and has a relatively simple, fast, and robust assembly procedure. The doubler achieved ≈10% efficiency at 765 GHz, giving 1.1 mW of peak output power when pumped with about 9 mW of input power at room temperature     

一种基于肖特基二极管的逆导型SOI-LIGBT

提出了一种逆导型(RC)SOI-LIGBT。通过在LIGBT阳极发射结反向并联一个肖特基二极管,在没有增大LIGBT正向导通压降的情况下,消除了传统阳极短路RC-LIGBT在正向导通时的电压折回效应。通过二维仿真软件对器件稳态、瞬态的电学特性进行了分析。仿真结果表明,与传统的SOI-LIGBT、续流二极管相比,该RC-LIGBT具有更高的击穿电压,且击穿电压不受阳极掺杂浓度的影响。该器件的反向恢复电荷减小了15.2%,软度因子提高一倍以上。     

A 250 GHz planar low noise Schottky receiver

A planar quasi-optical Schottky receiver based on the quasi-integrated horn antenna has been developed and tested over the 230–280GHz bandwidth. The receiver consists of a planar GaAs Schottky diode placed at the feed of a dipole-probe suspended on a thin dielectric membrane in an etched-pyramidal horn cavity. The diode has a 1.2Μm anode diameter and a low parasitic capacitance due to the use of an etched surface channel. The antenna-mixer results in a measured DSB conversion loss and noise temperature at 258GHz of 7.2dB±0.5dB and 1310K±70K, respectively, at room temperature. The design is compatible with SIS mixers, and the low cost of fabrication and simplicity makes it ideal for submillimeter-wave imaging arrays requiring a 10–20% bandwidth.     

A Low Noise 100 GHz Sideband-Separating Receiver

We have built a 100 GHz sideband-separating receiver. The receiver, a breadboard for the band 3 cartridges for ALMA, achieves a SSB noise temperature of 6hf/k with a 4–8 GHz IF. We show that it is possible to meet the ALMA specifications. The design of the receiver is reviewed and the relationships between the receiver noise temperature and properties of the components used in the receiver are discussed.     

A Broad-Band Traveling-Wave Maser for the Range 40-46.5 GHz

A tunable traveling-wave maser (TWM) for the frequency range 40-46.5 GHz has been developed, which is characterized by an extended instantaneous bandwidth. Andahssite (Al/sub 2/SiO/sub 5/ ) doped with Fe/sup 3/ atoms is used as the active crystal. The slow-wave structure is a digit comb with broad-band matching particularly suitable for the millimeter range. The new type of isolator employed is based on textured hexagonal ferrite materials, namely BaNi/sub 2/Sc/sub x/Fe,/sub 16/-/sub x/O/sub 27/. The net gain within the tuning band is 20-35 dB. The instantaneous bandwidth at a --3-dB level is 150-100 MHz, dependhsg on the net gain. The noise temperature at the input does not exceed 25° K.     

简洁构型与馈电的宽带双极化金属锥阵列天线北大核心CSCD

本文提出了一种宽带双极化金属锥阵列天线。该阵列天线以传统的旋转体天线结构为主体,通过在锥体底部开设四道正交的直通槽,以便在锥状单元内部形成可与地板间构成匹配谐振腔的开放式空腔结构。在阵列中,任意两个相邻的锥状单元之间可形成类似于Vivaldi天线的辐射缝隙结构。馈电采用同轴馈电方式,探针无弯折结构,金属锥体无弯折过孔。每个金属锥状单元独立,可极大简化加工、装配和维护过程。该天线具有两个正交极化,分别由左右和前后相邻单元构成。仿真结果表明,在频率范围为2～8GHz内,阵列大部分有源VSWR小于2,小部分端口有源VSWR小于2.5 (相对带宽为120%)。     

A Planar Gunn Diode Operating Above 100 GHz

We show the experimental realization of a 108-GHz planar Gunn diode structure fabricated in GaAs/AlGaAs. There is a considerable interest in such devices since they lend themselves to integration into millimeter-wave and terahertz integrated circuits. The material used was grown by molecular beam epitaxy, and devices were made using electron beam lithography. Since the frequency of oscillation is defined by the lithographically controlled anode-cathode distance, the technology shows great promise in fabricating single chip terahertz sources.     

Ni，Ti/4H-SiC肖特基势垒二极管

采用本实验室生长的4H-SiC外延片,分别用高真空电子束蒸Ni和Ti做肖特基接触金属,Ni合金作欧姆接触,SiO_2绝缘环隔离减小高压电场集边效应等技术,制作出4H-SiC肖特基势垒二极管(SBD)。该器件在室温下反向击穿电压大于600 V,对应的漏电流为2.00×10~(-6)A。对实验结果分析显示,采用Ni和Ti作肖特基势垒的器件的理想因子分别为1.18和1.52,肖特基势垒高度为1.54 eV和1.00 eV。实验表明,该器件具有较好的正向整流特性。     

A Superconducting Tunnel Junction Receiver for 230 GHz

The performance of superconducting tunnel junctions as high-frequency receivers is discussed. Low-noise mixing in superconductor insulator-superconductor (SIS) quasi-particle tunnel junctions has been seen for frequencies up to 400 GHz. Such mixers have the significant advantage of small local-oscillator power requirements. A receiver has been constructed which has a single-sideband (SSB) receiver noise temperature of 305 K at 241 GHz.     

A 24 GHz 6-Bit CMOS Phased-Array Receiver

This letter presents a 24 GHz 6 b phased-array receiver implemented in 0.13 mum CMOS. This design is based on a novel active vector generator that results in wideband quasi-quadrature vectors, which are used to synthesize the desired phase response. The active phase shifter has measured rms gain and phase errors of <0.5 dB and < 2.8deg at 23-24.4 GHz, resulting in a 6 b resolution. The phased-array receiver has a gain of 14 dB, a NF of 6 dB, a 3-dB gain bandwidth of 4.7 GHz and wideband input and output match. The chip consumes 30 mA from a 1.5 V supply with dimensions of 0.66 times 1.25 mm² including pads (0.5 times 1 mm² without pads).     

A sideband separating mixer for 85-115 GHz

This paper presents the results of development and tests of a sideband separating heterodyne receiver for the 85-115 GHz band with superconducting tunnel junctions (SIS) as frequency down converters. Sideband separation is achieved by using a quadrature scheme where two identical mixer junctions are pumped by a local oscillator (LO) with 90/spl deg/ phase difference. We used an innovative mixer layout where the quadrature scheme is implemented using waveguide-based and integrated on-chip components. We employed an additional pair of SIS junctions as terminations for LO-injection directional couplers.