THE PERFORMANCE OF THE SQUARE AND CONICAL CORRUGATED BAND .. HORNS AS MONOPULSE FEEDS IN THE MILLIMETRIC . . Lot fY SAKR A 1a1n SARREMEJEAN ABSTRACT A theoritical and a practical study of both of horns have been made to show their performance in the millimetric band. A conical corrugated horn terminating a circular corrugated waveguide, which can support the tracking modes, was constru

VERY SHORT HORN ANTENNAS FOR ARBITRARY POLARISAT~ON F .M. Landstor£er and R.R. Sacher" --<)L~ .~.~ fI'" ~ with ~ / ~t ~~.J. YV' L; ~ f-- ABSTRACT The paper deals with new types of horn antennas mini- mised lengths. Four different antennas for various applications are presented. The shape of these antennas was found by a combination of experimental and CAD-techniques. Providing

REDUCED SIZE SPIRAL ANTENNA T.E.MORGAN * ABSTRACT The cavity backed spiral antenna with a square configuration is described. It is shown that with continual development and an invention of a unique design of cavity the aperture of this type of antenna is reduced to approximately 0.1 square at its lowest operating frequency. The antenna radiates circularly polarised energy with a uni-directiona

A CIRCULARLY POLARIZED TRAVELING-WAVE CHAIN ANTENNA Johan Henriksson, Kari Markus, Martti Tiuri* ABSTRACT A novel traveling-wave antenna array with bent conductors as elements can give circularly polarized radiation. An expression for the far-field has been derived, from which the lengths and bending angle of the conductors can be calculated for circular polarization. A useful application w

SIDELOBE SUPPRESSION OF A PHASED ARRAY ANTENNA SYSTEM BY OPTIMIZING THE PHASE ERRORS OF THE ANTENNA R. Zeitz + ABSTRACT A new method of peak sidelobe suppression is studied on a phased array antenna system with about 60 array elements. Based on measurements at the input of the array elements the phase error curve is optimized for low sidelobes of the antenna. The results of theoretical and exp

PHASE-ONLY ADAPTIVE NULLING WITH DISCRETE VALUES E. Mendelovicz, * E. T. Oestreich * ABSTRACT A method, using a branch and bound algorithm, is described for obtaining optimal phase settings for jammer cancellation with an electronically scanning array (ESA) whose only variable parameters are element phases which vary in discrete steps. Methods vector, of continuous analysis cannot produce the

THINNED ARRAYS USING AMPLITUDE SHARING G.H. Walker* ABSTRACT The work described in this article falls into two parts both related to the practical application of phased arrays. Firstly an exploratory examination of the radiation patterns obtained from thinned planar arrays of circular outline. If the thinning is done by statistically random choice [l] at each grid point it appears that a reg

RADIATING PERFORMANCES OF PERISCOPE ANTENNA AT MILLIMETRIC WAVELENGTHS Nhu BUI-HAI ABSTRACT In radio links, the periscope antenna is used mainly to avoid terrain obstructions. This type of antenna comprises of a parabolic reflector located on the ground which radiates vertically and illuminates a passive reflector located at the top of a pylon. This passive reflector reflects the beam in the de

ADVANCED DESIGN CONCEPTS IN GROUND STATION ANTENNAS A. G. Cha,t D. A. Bathkert and W. F. Williamst ABSTRACT Large ground station antennas traditionally are of the symmetric Cassegrainian dual reflector type. New concepts, such as clear aperture (no blockage) designs, offset dual shaped reflectors and dual frequency band feed systems are examined in this paper as possible future large aperture

A TWO-REFLECTORBEAMWAVEGUIDEFEED FOR INTELSAT-A GROUNDSTATION ANTENNASWITH FREQUENCYREUSE OPERATION U. Leupelt ABSTRACT A beam waveguide feed system for large ground station antennas composed of only two beam reflectors is described. It is fully capable of 4/6 GHz frequency reuse operations. After discussing the main design principles the RF-properties of the beam waveguide are demonstrated by sca