{"title":"A Millimeter-Wave Gunn-Oscillator, Tunable with a Barium-Ferrite Sphere","authors":"M. Lemke","doi":"10.1109/EUMA.1979.332645","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332645","url":null,"abstract":"First results of a 65 GHz barium-ferrite tuned Gunn-oscillator are reported, similar to the YIG-sweepers. Electronic tuning is accomplished by a single crystal barium-ferrite sphere coupled to the image line oscillator circuit. The high internal field of the ferrite considerably reduces the external magnetic field required for ferrimagnetic resonance at mm-wave frequencies. The new mm-wave oscillator design has the potential for wide tuning ranges and good noise performance.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115187305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Near-Field Analysis by the Vector Wave Expansion Technique and the FFT","authors":"E. Ojeba","doi":"10.1109/EUMA.1979.332659","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332659","url":null,"abstract":"The dyadic Green's function expanded in the vector waves (cylindrical or spherical) is used to determine, from source function, the coefficient of expansion of the source fields. The reconstructed field over the surface of any cylinder or sphere surrounding the source is reduced into a two dimensional Fourier transform which is then evaluated using the Fast Fourier Transform (FFT) algorithm. This yields treamendous computational efficiency over the conventional integration of the aperture sources. Furthermore, the present technique, illustrated with rectangular and circular apertures, has wider applications than the recently reported Plane Wave Approach which has comparable computing efficiencies.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115542554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Image Recovery Millimeter-Wave Mixer","authors":"B. Vowinkel","doi":"10.1109/EUMA.1979.332668","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332668","url":null,"abstract":"This paper describes the design of an 80 GHz image recovery mixer that has a conversion loss of 4.4 dB. The image filter is a circular highpass filter using the cutoff properties of a waveguide section with reduced diameter. LO injection is preformed by a TE111-mode bandpass filter. The mixer noise temperature is 650 K at room temperature and 280 K at 20 K. The lower sideband suppression is better than 40 dB.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129909036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The TDRSS 18.3-Meter Ku-Band Antennas","authors":"A. Gianatasio, T. Leonard","doi":"10.1109/EUMA.1979.332688","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332688","url":null,"abstract":"Three 18.3 meter diameter Ku-band antennas have recently been completed as part of the Tracking and Data Relay Satellite System (TDRSS) Ground Station at the NASA Johnson Space Center, White Sands Test Facility in New Mexico, U.S.A. These antennas, which are believed to be among the largest Ku-band satellite communications antennas to date, exhibit directivities in excess of 68 dBi and half power beamwidths of less than 0.08°. Additional performance requirements include autotrack accuracies of greater than 0.01°, frequency reuse, and suppressed intermodulation products (IMP). This paper describes some of the design, analysis, and measurement techniques which were used with these high-gain antennas.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127026456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Statistical Predictions During Rain for Dual-Polarization Systems","authors":"J. Kanellopoulos, R. Clarke","doi":"10.1109/EUMA.1979.332658","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332658","url":null,"abstract":"A theoretical formula is derived for the joint statistics of cross-polarization discrimination (XPD) and rain attenuation for a microwave link, assuming log-normal and normal forms for the rain attenuation and XPD distribution respectively. This formula is used to predict the distribution of XPO conditional on the co-polar rain attentuation, and also the distribution of XPD during a rain fade. Experimental results from Atlanta, Georgia and from Southern England are compared with theoretical curves, and the agreement is encouraging. Finally, a formula for the estimation of outage time on microwave links, appropriate to dual-polarization frequency-reuse systems has also been derived.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123957372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Importance of Harmonic Terminations in Performances of a Class-C UHF Transistor Power Amplifier","authors":"A. Azizi, Shamsur R. Mazumdert, F. Gardiol","doi":"10.1109/EUMA.1979.332649","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332649","url":null,"abstract":"The influence of 2nd harmonic on the performances of an UHF class-C transistor power amplifier was determined. A matching circuit was designed, in which the reactive impedance termination presented at the second harmonic can be varied without affecting the impedance presented at the fundamental frequency. The main performance characteristics of the transistor power amplifier (output power, efficiency, intermodulation) were then determined, using two such matching circuits at the input and the output ports of the transistor. A graphical presentation of the results facilitates the choice of the 2nd harmonic terminations which significantly improve the performances of the amplifier.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124022632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Advanced Design Concepts in Ground Station Antennas","authors":"A. Cha, D. Bathker, W. Williams","doi":"10.1109/EUMA.1979.332690","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332690","url":null,"abstract":"Large ground station antennas traditionally are of the symmetric Cassegrainian dual reflector type. New concepts, such as clear aperture (no blockage) designs, offset dual shaped reflectors and dual frequency band feed systems are examined in this paper as possible future large aperture ground facilities. It is shown that offset dual reflectors offer prospectively superior performance compared to the standard symmetric system. Theoretical designs of offset dual shaped reflectors for ground station applications are considered utilizing a newly developed synthesis approach. Recent innovations in feed design and engineering, including the S/X dichroic reflex system for the NASA/JPL 64-m and 34-m antenna projects and a dual band common aperture corrugated feed under development are discussed.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"189 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123212875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A High Performance 8 GHz, 8 PSK Digital Radio","authors":"G. Russo, Paul P. Hartmann","doi":"10.1109/EUMA.1979.332709","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332709","url":null,"abstract":"Rapid growth and modernization of microwave communications is currently taking place in the commercial and military environments. Much of this growth is being accomplished through digital transmission and calls for efficient utilization of frequency spectrum allocated for LOS communications. As the bit efficiency and data rates of digital radio systems have increased, the problems associated with multipath phenomena have become more evident. To minimize outages and to meet path availability objectives diversity protection alone, in many instances, is not sufficient. However, diversity protection coupled with an adaptive equalizer will meet the objective in all but a few severe cases. This paper describes a digital radio system in the 8 GHz band with 8 PSK modulation and nominal data rates of 45 Mb/s and 90 Mb/s. Multipath propagation and its effects on digital transmission are discussed. Improvements in bit error rate threshold with the use of an adaptive equalizer designed into the receiver are also presented.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"78 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126237291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Radiating Performances of Periscope Antenna at Millimetric Wavelengths","authors":"N. Bui-Hai","doi":"10.1109/EUMA.1979.332691","DOIUrl":"https://doi.org/10.1109/EUMA.1979.332691","url":null,"abstract":"In radio links, the periscope antenna is used mainly to avoid terrain obstructions. This type of antenna comprises of a parabolic reflector located on the ground which radiates vertically and illuminates a passive reflector located at the top of a pylon. This passive reflector reflects the beam in the desired direction. Most of the studies about periscope antenna concern the gain problems and rarely the radiation pattern. Due to the large dimension of the periscope antenna, it is very difficult to investigate the radiation patterns. Our studies at millimetric wavelengths allow to reduce these dimensions. So that the radiation patterns of a periscope antenna over 360° can be measured and conclusions can be drawn concerning the influence of periscope antenna parameters :height, shape and dimensions of the passive reflector and, also, the effects of the support and the pylon.","PeriodicalId":128931,"journal":{"name":"1979 9th European Microwave Conference","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1979-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131925563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
