Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124433
H. Kodera, Y. Kaneko, H. Sato
A half-micron gate GaAs MESFET is designed and fabricated for the minimum gate parasitics. The single bonding-pad design of the gate and intentional side-etching of the lower layer of the double-layered Schottky-gate satisfy the above requirement. The best noise figure so far measured is 2.5 dB at 10 GHz for the packaged device and 2.1 dB at 12 GHz for the chip device. An X-band unit amplifier is designed for the FET chip. It can be cascaded to get a specified power gain or modified to have a necessary bandwidth.
{"title":"A Half-Micron Gate Low Noise GaAs MESFET and Amplifiers","authors":"H. Kodera, Y. Kaneko, H. Sato","doi":"10.1109/MWSYM.1977.1124433","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124433","url":null,"abstract":"A half-micron gate GaAs MESFET is designed and fabricated for the minimum gate parasitics. The single bonding-pad design of the gate and intentional side-etching of the lower layer of the double-layered Schottky-gate satisfy the above requirement. The best noise figure so far measured is 2.5 dB at 10 GHz for the packaged device and 2.1 dB at 12 GHz for the chip device. An X-band unit amplifier is designed for the FET chip. It can be cascaded to get a specified power gain or modified to have a necessary bandwidth.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117070533","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124350
H. Gnerlich, J. Ondria
Low frequency current and voltage fluctuations have been measured, and it has been confirmed that noise in packaged Transferred Electron Devices (TEDs) is due to three distinct noise mechanisms: Flicker, generation-recombination, and thermal noise. For Transferred Electron Oscillators (TEOs), this low frequency noise is unconverted into the microwave frequency range and adds to the intrinsic RF noise. We have found that, between 1 kHz and 1 MHz off the carrier, temperature dependent generation-recombination noise is the main contributor to the total noise. An improved model of a noisy TEO is presented. This model permits the calculation of AM and FM noise spectra from device and circuit parameters for measured low frequency noise or the derivation of device characteristics from noise and circuit parameter measurements.
{"title":"A New Look at Noise in Transferred Electron Oscillators","authors":"H. Gnerlich, J. Ondria","doi":"10.1109/MWSYM.1977.1124350","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124350","url":null,"abstract":"Low frequency current and voltage fluctuations have been measured, and it has been confirmed that noise in packaged Transferred Electron Devices (TEDs) is due to three distinct noise mechanisms: Flicker, generation-recombination, and thermal noise. For Transferred Electron Oscillators (TEOs), this low frequency noise is unconverted into the microwave frequency range and adds to the intrinsic RF noise. We have found that, between 1 kHz and 1 MHz off the carrier, temperature dependent generation-recombination noise is the main contributor to the total noise. An improved model of a noisy TEO is presented. This model permits the calculation of AM and FM noise spectra from device and circuit parameters for measured low frequency noise or the derivation of device characteristics from noise and circuit parameter measurements.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"738 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128920264","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124396
R. L. Ernst, R. Camisa, A. Presser
The graceful degradation properties of matched isolated power combiners as a function of amplifier failures of the same type has been determined using general techniques applicable to all such circuits. The effects of complete amplifier failures, amplitude and phase imbalances and poor VSWRs on overall combiner system output power, combining efficiency and input-output impedances can be determined by the resulting equations and plots.
{"title":"Graceful Degradation Properties of Matched N-Port Power Amplifier Combiners","authors":"R. L. Ernst, R. Camisa, A. Presser","doi":"10.1109/MWSYM.1977.1124396","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124396","url":null,"abstract":"The graceful degradation properties of matched isolated power combiners as a function of amplifier failures of the same type has been determined using general techniques applicable to all such circuits. The effects of complete amplifier failures, amplitude and phase imbalances and poor VSWRs on overall combiner system output power, combining efficiency and input-output impedances can be determined by the resulting equations and plots.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128947859","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124352
G. Engen
Although the six-port measurement technique is rapidly gaining the attention of the microwave community, theoretical development, to date, yields but limited intuitive insight into how the technique actually works. This paper presents an alternative introduction to the general subject which provides this insight.
{"title":"The Six-Port Reflectometer: An Alternative Network Analyzer","authors":"G. Engen","doi":"10.1109/MWSYM.1977.1124352","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124352","url":null,"abstract":"Although the six-port measurement technique is rapidly gaining the attention of the microwave community, theoretical development, to date, yields but limited intuitive insight into how the technique actually works. This paper presents an alternative introduction to the general subject which provides this insight.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129874187","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124419
H. Komizo, Y. Arai, T. Saito
An FM transmitter with a power efficiency of 11.5 % was developed utilizing GaAs power MESFETs for a 7 GHz FM radio-relay equipment. The transmitter, which consists of an FM modulator and power amplifiers, provides an output power of 1 watt and transmitting capability of 960 telephone circuits.
{"title":"A 7 GHz FM Transmitter Utilizing GaAs Power MESFETs","authors":"H. Komizo, Y. Arai, T. Saito","doi":"10.1109/MWSYM.1977.1124419","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124419","url":null,"abstract":"An FM transmitter with a power efficiency of 11.5 % was developed utilizing GaAs power MESFETs for a 7 GHz FM radio-relay equipment. The transmitter, which consists of an FM modulator and power amplifiers, provides an output power of 1 watt and transmitting capability of 960 telephone circuits.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128815837","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124463
K. Schunemann, R. Knochel, G. Begemann
The electrical performance of active microwave components for radio link systems is described, which have been realized utilizing evanescent mode resonators. This waveguide-below-cutoff technique is shown to be an alternative to the techniques established till now.
{"title":"Components for Microwave Integrated Circuits with Evanescent Mode Resonators","authors":"K. Schunemann, R. Knochel, G. Begemann","doi":"10.1109/MWSYM.1977.1124463","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124463","url":null,"abstract":"The electrical performance of active microwave components for radio link systems is described, which have been realized utilizing evanescent mode resonators. This waveguide-below-cutoff technique is shown to be an alternative to the techniques established till now.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129062147","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124456
H. Kritikos, K. Foster, H. Schwan
Temperature profiles are calculated in tissue models exposed to microwave radiation, by solving the heat transport equation taking into account thermal conduction, thermal convection due to blood flow, and surface cooling of the tissue. We consider two idealized models representing limiting cases of the microwave heating behavior of actual tissue sections. The first consists of a semi-infinite tissue slab exposed to plane electromagnetic radiation; the second considers focused microwave heating in a finite volume of tissue. In both cases, the steady state temperature profile is largely determined by the blood flow and can be considerably different from the microwave energy deposition pattern. In the steady state, the blood flow at physiological levels creates an effective diffusion length of about 1 cm which averages out the temperature variation in the tissue.
{"title":"Effect of Surface Cooling and Blood Flow on the Electromagnetic Heating of Tissue","authors":"H. Kritikos, K. Foster, H. Schwan","doi":"10.1109/MWSYM.1977.1124456","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124456","url":null,"abstract":"Temperature profiles are calculated in tissue models exposed to microwave radiation, by solving the heat transport equation taking into account thermal conduction, thermal convection due to blood flow, and surface cooling of the tissue. We consider two idealized models representing limiting cases of the microwave heating behavior of actual tissue sections. The first consists of a semi-infinite tissue slab exposed to plane electromagnetic radiation; the second considers focused microwave heating in a finite volume of tissue. In both cases, the steady state temperature profile is largely determined by the blood flow and can be considerably different from the microwave energy deposition pattern. In the steady state, the blood flow at physiological levels creates an effective diffusion length of about 1 cm which averages out the temperature variation in the tissue.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127672688","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124353
C. Hoer
Theory is presented for designing a microwave network analyzer which measures the circuit parameters device by connecting small portable 6-port reflectometers on each side of the 2-port. Several techniques are described, including self-calibration.
{"title":"A Microwave Network Analyzer Using Two 6-Port Reflectometers","authors":"C. Hoer","doi":"10.1109/MWSYM.1977.1124353","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124353","url":null,"abstract":"Theory is presented for designing a microwave network analyzer which measures the circuit parameters device by connecting small portable 6-port reflectometers on each side of the 2-port. Several techniques are described, including self-calibration.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130259074","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124478
E. Wolff
A Public Service Communications Satellite study has been undertaken at the NASA Goddard Space Flight Center (GSFC) to define the problems and opportunities of a renewed NASA role and the form such NASA involvement should take. Civilian communications satellite technology could be applied now to the betterment of life on earth. Citizens who reside in remote regions do not enjoy the quality of public services available to those in more densely populated areas. There are people in the United States without access to the normal communications services (telephone and television). There are people in thinly populated rural areas that lack the services of medical professionals enjoyed by urban residents. The use of satellite techniques holds tremendous promise for increasing the effectiveness of public safety personnel by enabling more rapid response and coordination to emergency situations. Small portable, mobile, and hand-held communication devices are an essential ingredient for efficient services for ambulances, police, fire and rescue vehicles.
{"title":"Public Service Satellite Communications Opportunities","authors":"E. Wolff","doi":"10.1109/MWSYM.1977.1124478","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124478","url":null,"abstract":"A Public Service Communications Satellite study has been undertaken at the NASA Goddard Space Flight Center (GSFC) to define the problems and opportunities of a renewed NASA role and the form such NASA involvement should take. Civilian communications satellite technology could be applied now to the betterment of life on earth. Citizens who reside in remote regions do not enjoy the quality of public services available to those in more densely populated areas. There are people in the United States without access to the normal communications services (telephone and television). There are people in thinly populated rural areas that lack the services of medical professionals enjoyed by urban residents. The use of satellite techniques holds tremendous promise for increasing the effectiveness of public safety personnel by enabling more rapid response and coordination to emergency situations. Small portable, mobile, and hand-held communication devices are an essential ingredient for efficient services for ambulances, police, fire and rescue vehicles.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121429480","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}
Pub Date : 1977-06-21DOI: 10.1109/MWSYM.1977.1124400
J. Vokes, W. P. Barr, J. R. Dawsey, B. T. Hughes, Susan Shrubb
This paper describes on the advantages of figures of 2.2 dB at the factors affecting the performance of low noise FET amplifiers, with particular emphasis coplanar waveguide as the microwave circuit. RF results include overall amplifier noise 7.5 GHz from devices made from two quite different GaAs structures.
{"title":"A Low Noise FET Amplifier in Coplanar Waveguide","authors":"J. Vokes, W. P. Barr, J. R. Dawsey, B. T. Hughes, Susan Shrubb","doi":"10.1109/MWSYM.1977.1124400","DOIUrl":"https://doi.org/10.1109/MWSYM.1977.1124400","url":null,"abstract":"This paper describes on the advantages of figures of 2.2 dB at the factors affecting the performance of low noise FET amplifiers, with particular emphasis coplanar waveguide as the microwave circuit. RF results include overall amplifier noise 7.5 GHz from devices made from two quite different GaAs structures.","PeriodicalId":299607,"journal":{"name":"1977 IEEE MTT-S International Microwave Symposium Digest","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1977-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123759532","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}
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