A COOLED SCHOTTKY-DIODE MIXER FOR 75-120 Antti GHz V. Raisanen*+, C. Read Predmore*, Peter T. Parrish*, Paul F. Goldsmith*, Jose L. R. Marrero*, Richard A. Kot*, Martin V. Schneider** ABSTRACT A cryogenic, ultra low noise mixer has been designed and built at the Five College Radio Astronomy Observatory. New details of this mixer include improved waveguide, back short , RF-filter and IF-matching

BROAD-BAND TUNABLE GaAs-FET EVANESCENT-MODE RESONATORS OSCILLATOR WITH HYBRID-COUPLED MICROSTRIP AND A. Jacob and R. Knochel. ABSTRACT An integrated GaAs-FET oscillator pensive tuning of the oscillation 950 MHz with little power variation This was achieved by coupling the mode cavity, which is part of the a varactor diode has been mounted additional electronic tuning over has been developed

50-50~ PACKAGED GaAs FET FOR X AND Ku BANDS H.DEREWONKO + ABSTRACT. Everyone Parasitic losses power reduce knows how difficult reaction, stability, are presented increased power matched with it gain, is to use packaged output biased power with FETS above 8 GHz. circuit Medium in X power. elements input-output and self 50, VSWR and matching and bandwidth. lumped FETs internally and Ku band

DESIGN OF BROADBAND MICROWAVE FET-AMPLIFIERS Martti Valtonen ABSTRACT A new design method for broadband microwave FET-amplifiers is outlined. The design procedure utilizes the measured S-parameters of the FET and neither a new synthesis method nor a new transfer function approximation is required. Instead the equalizing networks are developed from conventional matched Butterworth or Chebyshe

CHARACTERISTICS OF LOW-NOISE GaAs MESFETS FROM 300K TO 20K S. Weinreb * and T. M. Brookes t ABSTRACT Measurements of the noise temperature and transconductance of a GaAs field-effect transistor at temperatures of 300K and 17K are reported as a function of drain current. These results are compared with theory and the contributions of various noise mechanisms to the total noise temperature are

4 GHz BAND FET AMPLIFIER AT -50°C T. Nakazawa ABSTRACT , K. Ogiso WITH THE NOISE TEMPERATURE OF 55K , F. Takeda, S. Miyazaki and A. Nara Thermoelectrically cooled 4 GHz band FET amplifier with noise temperature of 55K has been developed for low noise amplifier of satellite communications earth stations. In this amplifier with the FET which was developed in our company, the new design metho

A NOVEL NOISE MODEL FOR SUBMICROMETER GATE FET I s B. Carnez, A. Cappy, G. Salmer, E. Constant ABSTRACT A novel noise model for submicrometer gate FET's is described: it takes into account the non stationnary electron dynamics effects. It allows us to evaluate the intrinsic and extrinsic FET noise figure and to give some informations about the origin of noise in MESFET. A comparison betwe

TRANSIENT THERMAL STATES IN MICROWAVE AVALANCHE DIODES Zbigniew J. STASZAK and Janusz GULCZYNSKI ABSTRACT Transient thermal states of microwave avalanche diodes have been investigated using the computer model Iing approach. Some of the results of computations have been experimentally verified using the developed new measurement technique. Investigations have ~en caYried out for sil ico

UNIFOIM ION IMPLANl'ATIONFOR GaAs FETs PROCESSING VARIABIES - RELATION TO MATERIAL AND P.A. Leigh and N. McIntyre ABSTRACT Uniformly ion implanted semi-insulating wafers of gallium arsenide are desirable if the material is ever to be used for high yield integrated circuit manufacture. In this work an established implantation and device technology is described. Careful measurements and charac

GaAs p+-n+-i(lI)-n+ TUNNETT DIODE J. Nishizawa*, K. Motoya** and K. Suzuki* ABSTRACT The Tunnett (tunnel injection lransit lime) diode has been evaluated to be useful device in the frequency range from 100 to 1000 GHz following SIT till 100 GHz. The higher oscillation frequency with lower bias voltage and lower noise level of the Tunnett diode will be superior to those of the Impatt diode. Ga