A SENSITIVE AND PERMANENT JO~EPHSON MIXER FOR MilLIMETER WAVES J. Edrich ABSTRACT A new method to construct permanent Josephson mixers for millimeter waves is described. In contrast to conventional point contacts which are mechanically unstable and require adjustments after each cooldown, these point contact junctions are set at room temperature, stay mechanically stable and can be temperatu

BROADBAND MATCHING OF MICROSTRIP DIFFERENTIAL PHASE SHIFTERS B. Schiek, J. Kohler, W. Schilz ABSTRACT Meanderline phase shifters in microstrip are badly matched (vswr ~ 2), due to the difference in phase velocity of the odd and even mode of the coupled transmission lines. This is overcome by a stepped impedance design, allowing to realize e.g. a 90º phase shifter with a return loss better than 3

ACCURATE ANALYSIS AND DESIGN OF MICROSTRIP INTERDIGITATED COUPLERS Vittorio Rizzoli-- Alessandro Lipparini- Abstract. The electrical behaviour of interdigitated directional couplers in an inhomogeneous dielectric medium is analyzed. Thanks to the symmetry properties of the device, the concepts of even and odd networks can be applied, leading to simple, closed-form expressions for coupler

EFFECTS OF THE EVEN AND ODD PHASE VELOCITY SEPARATION ON THE BANDWIDTH OF NONUNIFORM J.P. Villotte, LINE MICROSTRIP COUPLERS. ~ LIMITATION Y. Garault, D. and J. Rousset ABSTRACT Frequency response of nonuniform line micros trip couplers is given by using a second order theory applied for the even and odd signals which have unequal velocities. This condition leads to finite isolation which beco

SURFACE. WAVES IN MICROSTRIP CIRCUITS R.J. COLLIER and P.D. WHITE* ABSTRACT The launching of surface waves by discontinuities in microstrip circuits can cause extra coupling between adjacent devices. This paper gives measurements of the efficiency of an open circuit in microstrip to both launch and receive surface waves. The measurement technique is described in which the radiated waves from

THEORETICAL NON-UNIFORM MICROSTRIP AND EXPERIMENTAL IN THE ANALYSIS FREQUENCY OF RANGE LINES 2-18 GHz Guglielmo D'lnzeo, Franco Giannini and Roberto Sorrentino ABSTRACT In the field of microwave integrated devices, non-uniform microstrip lines have recently received considerable attention. Among these, with regard to band-width and losses, non-uniform microstrips with a continuously varyi



New Transistor Operating for High Frequency and High Power Jun-ichi Nishizawa * and Yoji Kato ** The main mechanism of operation of a new transistor which shows exponential I-V character, is based on the static induction and is called SIT (Static Induction Transistor). SIT is a promissing device also for higher frequency operation because of (1) short channel length, (2) lower gate ser

GaAs POWER MESFET AMPLIFIER DESIGN John A. Angus, David A. Abbott and Edward Kelly ABSTRAC T GaAs power MESFETs capable of producing in excess of 600 mWwith 6 dB gain and 33% power added efficiency at 8 GHz have been produced. The use of these devices in amplifiers for S, C and X-bands will be described. Techniques for effective heat sinking whilst maintaining low parasitics will be discuss

IMPROVEMENTS IN LOW NOISE GALLIUM ARSENIDE FETS FOR X-BAND APPLICATIONS Richard S. Butlin, Donald Parker, Anthony J. Waller and James A. Turner* ABSTRACT A single stage narrow band amplifier operating at 8 GHz has been developed with a noise figure of 2.2 dB and associated gain of 7.0 dB. Correcting for microstrip losses yields a device noise figure of 1.9 dB and associated gain of 7.6 dB