HIGH EFFICIENCY MICROSTRIP ANTENNA ARRAY Ferenc VOLGYI ABSTRACT A fixed beam (broadside) two-dimensional microstrip array of 16x16 resonant rectangular radiating elements at the frequency of 8.15 GHz with a gain of 29.5 dB is presented. A modular approach is utilized in which a given antenna is used as a building block for a higher-gain antenna. The high efficiency is achieved by optimising the l

INPUT IMPEDANCE AND RADIATION PATTERN OF PHASED ARRAYS OF RECTANGULAR MICROSTRIP PATCH ANTENNAS WITH A DIELECTRIC COVER H.-J. Eul and V. Hansen ,. ABSTHACT The input impedances of phased arrays of rectangular patch antennas with a dielectric cover are calculated by solving an integral equation for the antenna currents in the spectral domain. Radiation patterns are evaluated by considering the c

ANTENNA AND SYSTEM DESIGNS FOR MOBILE COMMUNICATION SATELLITES and L.A.Wegrowicz* H.J.Moody ABSTRACT In this paper the requirements and concepts for the M-Sat system and antenna design are discussed. Several designs developed during the MSat program are presented. 

RESULTS OF A FEASIBILITY STUDY FOR THE ANTENNAS OF A EUROPEAN DBS SATELLITE P. De Vincenti, G. Ruggerini*, P. Russo. ABSTRACT This paper presents the main results of a feasibility study aimed at defining the antenna subsystem of a European DBS satellite. The antennas of the satellite radiate a large number of channels over seven multinational, partially overlapping, coverages. The mass and v

HIGH CARRIER REJECTION FOR A 3.7 TO 4.2 GHz BPSK MODULATOR SOMBRIN J.**, LAPIERRE L. **, SAUTEREAU J.F*** LARROQUE J.*, ABSTRACT: This paper presents the performances of a 3.87 GHz balanced modulator, which is used for a fourphase remodulation demodulator. This modulator uses planar technology with slotlines and mi crostrip lines engraved on an Epsilam-type substrate, and two beam-lead Schott

INFLUENCE OF PARAMETERS ON COMMUNICATION SATELLITE SIGNAL INTERFERENCE MODELLING D.C. Carpenter* and A.P. Gallois ABSTRACT An introduction to inter-system signal interference for satellite communications is given. Particular parameters are highlighted. Spectral analysis for F.M. video spectra is outlined. Influence of climatic conditions and the statistical approach used is explained. Spac

A NEW GENERATION Of 12GHz SATELLITE APPLICATIONS CHANNEL DEMULTIPLEXERS FOR COMMUNICATIONS H. GREGG, R.J. ABSTRACT BRUNT and M.C. HUGHES * Five types of 12GHz Demultiplexer are presented. The five types are constructed in similar fashion and provide 22 highly selective channels with very flat gain and group delay responses spanning the band 10.9 to 12.7GHz in discrete segments. State of the

A HIGH PRECISION/HIGH PSK/AM ISOLATION PLANAR MODULATOR MM-WAVE U. Goebel Abstract A new approach to broadband mm-wave binary PSK/AM modulators is proposed using a double balanced configuration of 4 PIN diodes in a waveguide-coupled stripline circuit. The transition from two in-line orthogonal waveguides to four single-ended 180. reflection modulators is realized as a planar power divider/comb

THE ISIS MULTI-JUNCTION PULSED MILLIMETER VARACTOR AS A WAVE HARMONIC GENERATOR M.E. HINES, P.W. STAECKER, F. OCCHIUTI AND J.F. CUSHMAN* ABSTRACT Millimeter-wave varactor diodes of greatly improved power generation capability have been developed using multi-layer epitaxial GaAs material. These are "stacked" multijunction diodes in a monolithic form, with as many as three active varactor junctio

EFFECTS OF INSULATING DIELECTRIC LAYERS IN MILLIMETER-WAVE PLANAR TRANSMISSION LINES Brian Young * and Tatsuo Itoh * ABSTRACT Insulating dielectric layers added to waveguiding structures to reduce the conductor losses at high frequencies complicate the structure and usually introduce dominant mode crossing and leakage. A qualitative study is used to derive a design constraint that ensures that ins