TEMPERATURE ANALYSIS AND THERMAL RESISTANCE OF A MATRIX OF IMPATT DIODES * * A. Strum + and A. Bar-Lev ABSTRACT A composite Impatt device consisting of a matrix of Impatt diodes, in a multimesa structure, with a common n + electrode region and a common heatsink, represents a complex non-linear thermal problem since each diode heat contribution depends indirectly on its junction temperature. Numer

MEASUREMENT AND CALCULATION OF THE COMPLEX SCATTERING MATRIX FOR A DIELECTRIC CYLINDER S. Riegger*, D. Hollmann*, G. Schone*, W. Wiesbeck* ABSTRAC The complex scattering matrix [S] represents the polarization signature of targets. In this paper the scattering of a lossy dielectric cylinder with dimensions even in order of the wavelength is investigated. Both, an analytical and a numerical method f

A FIVE-PORT MUnoz REFLECTOMETER USING A THREE J.M., PROBES Martin SCHEME E. J., Margineda J., Zamarro ABSTRACT A five-port automatic reflectometer is presented. The measuring cell consists of three fixed probes on a rectangular waveguide. The system performance is described and a procedure for source matching error correction is proposed and tested. The calibration procedure, unlike for mo

SYNTHESIS OF RADIOWAVE DISCRETE INVARIANT SENSORS OF INTERFACE POSITION m TWO COMPONENT MEDIA - B. V. Lunkin, ABSTRACT N. A. Kriksunova* A new approach is suggest to the problem of discrete (multipoint) measurements of an interface position in dielect ric two-component media. The design of sensors suggested for the purpose rests upon the capability of distributed electromagnetic systems to gen

OPTIMUM DESIGN OF A MATCHING NETWORK FOR TE11 MODE COAXIAL WAVEGUIDE HORNS D. SAVINI (*), G. FIGLIA (*), K.v.t. KLOOSTER (**) ABSTRACT The paper deals with the design of an irises matching network in coaxial waveguide. The design procedure allows to get the optimum solution without any iterative experimental analysis. The accuracy and the reliabi1ity of the procedure arise from: the complete

BEAM-FORMING SATELLITES NETWORKS FOR FUTURE EUROPEAN COMMUNICATION M. LISI ABSTRACT IE This paper reviews some state-of-the-art topics on beamforming networks for satellite multibeam antennas;it also presents the results of relevant R&D activities promoted by ESTEC on this subject. 

RADOME EFFECTS ON MICROSTRIP ANTENNA PARAMETERS B. Roudot, J.R. Mosig and F.E. Gardiol* ABSTRACT Green's function for microstrip two-layer cases are studied and determined. Radome effects on microstrip antenna parameters are presented. Numerical results for rectangular patches are compared with experiment for several values of dielectric constant and radome thickness. 

Effects of dielectric microstrip antennas truncation on the input impedance of monopole and P. Krier, C.M. Snowden, J.R. Richardson, and V. PostoyalkoJ ABSTRACT The variation of the input impedance of microstrip antennas on PTFE and GaAs substrates with substrate size is presented. This is of particular relevance to the design of monolithic active sub-arrays. The results show significant ch

COMPARISION OF MEASURED AND CALCULATED RADIATION COVERED ANTENNA UNDER RAIN AND SLEET CONDITIONS PATTERNS OF A RADOME Hakan A. Sandell1, ABSTRACT Markku I. Oksanen2 The 13.7 m radome covered antenna at Metsahovi has been used for SIRIO and OTS propagation measurements at 11.6 GHz. In this report the impact of a wet radome on measured radiation patterns has been compared with the theoretical p

RAY METHODS FOR TAPERED Ercan DIELECTRIC TOPUZ ANTENNAS ABSTRACT Due to their simplicity and versatility ray methods are well suited to the analysis of tapered dielectric antennas wherein the availability of fast algorithms which can yield a sufficiently accurate representation of the surface field distribution on the antenna is of great importance. The accuracy of the ray optical calculations