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1.
《Microwave Theory and Techniques》1984,32(5):498-507
A cryogenic 3-mm receiver has been developed which fully utilizes the low-noise potential of Schottky diodes by approaching the shot-noise limit within 10 percent. With a broad-band mixer design which properly terminates the input sidebands and reactively terminates the second harmonic of the local oscillator and its sidebands, the double sideband (DSB) mixer noise temperature is 35 K in the best case. This design has given an average DSB receiver noise temperature of 75 K over the 80 to 115-GHz band with a best noise temperature of 62 K. 相似文献
2.
An integrated 3mm-wave Schottky diode mixer and pseudomorphic high-electron-mobility transistor (PHEMT) IF amplifier with record noise performance at room temperature is described. The design has shown the room-temperature double-sideband (DSB) receiver noise temperature T R DSB of 190 K at 100 GHz due to a very low conversion loss in the full-height waveguide mixer and an ultra-low noise of the PHEMT IF amplifier. The receiver noise temperature has been reduced by a factor of 1.5 in comparison with the best previously reported 3mm-wave Schottky diode mixer receiver. 相似文献
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A Broad-Band Second-Harmonic Mixer Covering 76-106 GHz 总被引:3,自引:0,他引:3
《Microwave Theory and Techniques》1978,26(6):425-427
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. 相似文献
5.
《Microwave Theory and Techniques》1984,32(12):1579-1590
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. 相似文献
6.
Takafumi Kojima Kouichi Kuroiwa Yoshinori Uzawa Matthias Kroug Masanori Takeda Yasunori Fujii Keiko Kaneko Akihira Miyachi Zhen Wang Hideo Ogawa 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(11):1321-1330
We have developed a low-noise heterodyne waveguide Superconductor-Insulator-Superconductor (SIS) mixer with a novel local
oscillator (LO) injection scheme for the Atacama Large Millimeter/submillimeter Array (ALMA) band 10, over the frequency range
0.78–0.95 THz. The SIS mixer uses radio frequency (RF) and LO receiving horns separately and a waveguide 10 dB LO coupler
integrated in the mixer block. The insertion loss of the waveguide and coupling factor of the coupler were evaluated at terahertz
frequencies at both room and cryogenic temperatures. The double-sideband (DSB) receiver noise temperatures were below 330 K
(7.5hf/k
B) at LO frequencies in the range 0.801–0.945 THz. The minimum temperature was 221 K at 0.873 THz over the intermediate frequency
range of 4–12 GHz at an operating temperature of 4 K. This waveguide heterodyne SIS mixer exhibits great potential for practical
applications, such as high-frequency receivers of the ALMA. 相似文献
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8.
Schlecht E. Gill J. Dengler R. Lin R. Tsang R. Mehdi I. 《Microwave and Wireless Components Letters, IEEE》2007,17(12):879-881
We report on the design and performance of a novel broadband, biased, subharmonic 520-590 GHz fix-tuned frequency mixer that utilizes planar Schottky diodes. The suspended stripline circuit is fabricated on a GaAs membrane mounted in a split waveguide block. The chip is supported by thick beam leads that are also used to provide precise radio frequency (RF) grounding, RF coupling and dc/intermediate frequency connections. At room temperature, the mixer has a measured double sideband noise temperature of 3000 to 4000 K across the design band. 相似文献
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《Microwave Theory and Techniques》1958,6(3):311-314
The design of a series of broad-band Tchebycheff-type stepped waveguide transformers from various sizes of standard rectangular waveguides to a double ridged waveguide covering the frequency range of 4750 to 11,000 mc is described. Four separate transformers employing RG-67/U (WR-90), RG-68/U (WR-112), RG-106/U (WR-137), and WR-159 to Airtron ARA-133 double-ridged waveguide have been designed using this technique and cast in aluminum. The complete frequency range is covered by several pairs depending on which sizes of mating rectangular waveguides are desired. The RG-106/U design covers a frequency range of 53 per cent with a maximum VSWR of 1.08, while the other three designs each cover a slightly smaller frequency band with a VSWR not exceeding 1.05. Along with the experimental results obtained, an outline of the design method is given which can be used to design similar transformers between any compatible rectangular and double ridged waveguides. 相似文献
11.
Shin'ichiro Asayama Takashi Noguchi Hideo Ogawa 《Journal of Infrared, Millimeter and Terahertz Waves》2003,24(7):1091-1099
The design and performance of a fixed-tuned W-band SIS mixer with a wide band IF of 4.0-7.5 GHz is presented. Waveguide-to-stripline transition of the SIS mixer is designed using the lumped-gap-source port provided by HFSSTM. Measured receiver noise temperature is less than 25 K in the frequency range of 95-120 GHz, with a minimum value of around 19 K achieved. Mixer noise temperature is determined to be about 8.5 K, which is around twice the quantum limit (i.e., 2hw/k). In spite of the high IF frequencies (f 0 = 6 GHz), the performance of the SIS receiver is comparable or even superior to those of the best mechanically-tunable waveguide SIS receivers at low IF frequencies (f 0 = 1.5 GHz). This result suggests that it is easy to design waveguide-to-stripline transitions without scale-model measurements. 相似文献
12.
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 相似文献
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14.
Thomas B. Alderman B. Matheson D. de Maagt P. 《Microwave and Wireless Components Letters, IEEE》2008,18(5):353-355
The design, fabrication and test of a combined sub-millimeter wave mixer/doubler featuring a 380 GHz sub-harmonic mixer and a 190 GHz frequency doubler on a single quartz based microstrip circuit is reported in this letter. The integrated circuit uses separate flip-chip mounted planar Schottky diode components to perform the two functions. Measurements give best double sideband mixer noise temperatures of 1625 K at 372 GHz, and a corresponding mixer conversion loss of 8 dB. The measured fixed-tuned radio frequency bandwidth extends from 368 to 392 GHz, in good agreement with simulations. This work represents the first demonstration of a single substrate combined submillimeter wave mixer/doubler. 相似文献
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《Microwave Theory and Techniques》1967,15(11):629-635
The theory of mixer operation is briefly reviewed and the results presented in graphical form convenient to the designer. In particular, the minimum noise figure, conversion loss, and the source and output impedances are plotted as functions of the pulse duty ratio of the diode current. Emphasis is placed on the pulse duty ratio as a more fundamental parameter for defining mixer operation than the magnitude of the diode voltage which is generally nonsinusoidal. It is shown that Schottky diode mixers should exhibit single sideband noise figures as low as 3 dB at X band when used in conjunction with 1.5 dB noise figure IF amplifiers, provided the diodes have cutoff frequencies higher than 500 GHz. 相似文献
17.
《Electron Device Letters, IEEE》2009,30(3):206-208
18.
《Microwave Theory and Techniques》1956,4(3):181-183
This paper describes a broad-band dual-mode waveguide transducer designed to couple two orthogonal TE/sub 11/ circular waveguide modes in separate rectangular waveguide ports. A compact, rugged, and economical junction has been developed to operate from 8600 mc to 9600 mc with a vswr of less than 1.15 at the rectangular port and a mode isolation of 50 db or greater. Developmental models are described to indicate the evolution from theory to the final model. Some problems encountered in attaining a small physical size are discussed in detail. The new junction has application to mode multiflexing, circular waveguide ferrite devices, circular polarization, and as a circular wave guide magic-T. 相似文献
19.
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。 相似文献
20.
F. Yang H. F. Meng W. B. Duo Z. L. Sun 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(5):630-637
Sub-harmonic mixers are the core element of terahertz room temperature, high spectral resolution heterodyne receivers for planetary science, and remote sensing. Here, terahertz sub-harmonic mixer up to 400 GHz using discrete Schottky diode is presented. Measured performance is in agreement with results from the linear and nonlinear co-simulations, and this methodology shows its practicability for the discrete planar GaAs Schottky diode-based terahertz core circuit design. 相似文献