Complete characterisation of leakywave antennas based on stepped rectangular waveguides Carlo Di Nallo, Fabrizio Frezza, Alessandro Galli and Paolo Lampariello Abstract A complete procedure has been carried out for the analysis and the design of a class of leaky-wave antennas based on 'stepped' rectangular waveguides, introducing a new topology which results quite advantageous in terms of compact

Analysis of slot array antennas radial fed line Manue. SI.,ra*, Marla V.ra and Antonio Q Plno** a on a Abstract An easy way to analyze a slot array fed through a radial line is presented. The analysis is based on a circuit approach where circuit parameters have been estimated using the first propagation mode in the radial line and the far field theory. Moment method full wave analysis has be

Cross-polarization causes by dichroic subreflectors of tripoles or loaded four- pole elements Benedikt A lIunk end Rudy Emrick ElectroScience Laboratory, The Ohio State University, 1320 Kinnear Road, Columbus, Ohio 43212 Frequency Selective surfaces (FSS) are widely used as subreflectorsin Cassegrain systems permitting the use oftwodifferentfeeds at differentfrequencies, see Figure1. This paper

8x8 Butler high power matrix at L-band A Nubia, .1M Montero, L Bustamante*, Dr G Crone** and N Hill*** Abstract Thispaper presents a ButlerMatrix with8 inputports and 8 output ports. Ituses 3 dB branch linecouplers, phase shifters,and TNCcoaxialconnectors,allofthem linkedby means of U-shape TEMtransmission lines. The design is focused in high power (220 watts) application, low PIMP and multipacti

Design and performance of an HTS beamforming network for satellite communications H Kobeissi and K Wu., D Drolet and M G Stubbs.., G Larralde and S Rao... Abstract A high temperature superconductor (HTS) beamforming network (BFN) is reported based on a multiple power divider technique involving a cascade of 3 dB branch-line couplers. The 1-to-4 HTS BFN was designed to operate over the frequency

A switched radial divider for an L.band mobile satellite antenna Ross S Varnes* Marek E Blalkowski** Abstract A multiway switched radial power divider for use in a mobile satellite antenna-array operating in the microwave L-band is described. The divider is designed using low-cost substrate and inexpensive switching diodes. It features good return loss and small insertion losses over a 7% bandwid

Direct calculation of the HBT small. signal equivalent circuit with, special emphasize to the feedback capacitance D Peters*, W Daumann*, W Brockerhoff*, R Reuter*, E Koenig**, F .. 'Tegude* Abstract In this paper a new direct evaluation technique for the small-signal equivalent circuit of AIGaAs/GaAs Heterojunction Bipolar Transistors is presented. Based on the known hot and cold measurement tec

Physical heterojunction bipolar transistor model for microwave large signal simulation U Schaper, D Ahlers Abstract A new physical large signal HBT model is proposed in this contribution. To our knowledge it is the first time that a physical large signal HBT model is implemented into a circuit simulator. The new HBT model describes the transistor action of the intrinsic HBT by an analytic formula

GaAs power HBTs with 84% power-added efficiency operating in C-X band Faal Ali, Colin Aitchison* Bert Hewitt and Abstract This paper describes the results of an experimental study of operating GaAs Power Heterojunction Bipolar Transistors (HBTs) in Class C bias mode over C-X frequency Bands. We find that the power-added efficiency (PAE) improves and power gain decreases in Class C when compared t

Design of experiments physical model .John. Atherton, Chrlatopher .. Snowden 8nd Roger D Pollard using a Abstract This paper describes the use of the Design of Experiments (DOE) technique with an accurate and efficient physical model. This approach allows for the systematic study of the effects of device geometry and process variations on electrical performance and demonstrates efficiently which