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EVOLUTION OF COMMUNICATION SYSTEMS FROM MICROWAVE TO OPTICAL FREQUENCIES
OPTICS OF GUIDED WAVES
OPTICS OF GUIDED WAVES Reinhard Ulrich ABSTRACT In multimode waveguides, many classical optical effects continue to exist in modified form, and new optical effects are observed. The talk gives a review of some of these effects. The thin-film optical waveguide, a 2 dimensional (2D) propagation medium, may be considered as a versatile artificial dielectric. Trough local design of the guide, a v
NEW LOW GAIN S-BAND SATELLITE ANTENNA WITH SUPPRESSED BACK RADIATION
NEW LOW GAIN S-BAND SATELLITE ANTENNA WITH SUPPRESSED BACK RADIATION N.C. Albertsen, + P. Ball~ng . + and F. Laursen ++ ABSTRACT: Theoretical and experimental results are presented for a waveguide antenna with a cardoid-shaped pattern. The antenna, which operates in the S band, is proposed for telemetry and telecommand on future scientific satellites. The radiation takes place thro
ACTIVE RECEIVING THICK FOLDED DIPOLES ARRAY WITH GOOD SENSITIVITY BETWEEN 0.4 GHz AND 1 GHz.
ACTIVE RECEIVING THICK FOLDED DIPOLES ARRAY WITH GOOD SENSITIVITY BETWEEN 0.4 GHz AND 1 GHz. ~~ J.P. DANIEL, G. DUBOST. ABSTRACT. This paper describes the design and testing of a broadband active thickfolded-dipole, used for reception, between 0.4 and 1 GHz. This active antenna wnich exibits a good sensitivity can be used as an element of a directive array without a loss of bandwidth
AN ELEMENT POSITION MODULATED ANTENNA ARRAY
AN BLIMBN'l POSITION MOOOLAmD ANT.INNA ARRAY G. S. SaDl'al. and M. G. Sharma' ABSTRACT Analysis has been presented for a non-uniformly spaced linear array of large number of isotropic elements at locations obtained by sinusoidal position modulation. Studies on the space factor of such an array reveal lower sidelobe and grating plateaux levels in comparison to the uniform array. This type of a
ELEMENT PATTERNS FOR LINEAR PHASED ARRAYS WITH DESCATTERING NETWORKS
ELEMENT DESCA PATTERNS FOR LINEAR PHASED ARRAYS WITH TT ERING NET WORKS J. Bach Andersen and Amir 1. Zaghloul ABSTRACT The limitations on the element pattern for linear arrays are studied and it is shown that the ideal element pattern is the omnidirectional pattern, leading to a very wide angular scan. Lossless interconnecting networks are used to improve the element pattern and the
MICROSTRIP ARRAY ANTENNA
MICROSTRIP ARRAY ANTENNA Anders G. Derneryd ABSTRACT An equivalent network for rectangular shaped microstrip radiating elements is derived. In order to simplify the problem the radiating elements are considered as two slots separated by a transmission line of low characteristic impedance. The slots are characterized by their equivalent admittances. The radiation conductance is derived and found
LARGE SIGNAL EFFECTS IN THE AVALANCHE REGION OF HIGH-EFFICIENCY IMPATT DIODES
LARGE SIGNAL EFFECTS IN THE AVALANCHE REGION OF HIGH-EFFICIENCY DIODES IMPATT P. A. Blakey* ABSTRACT The avalanche different even that this will structures. regions of 'lo-hi-lo' and 'hi-la' IMPATTs are significantly though their drift regions may be similar. It is likely cause differences in the large signal behaviour of the two This possibility is investigated using computer simulation.
THE DESIGN AND OPERATION OF TRAPATT DIODES FOR SYSTEMS REQUIREMENTS IN THE 1-5GHz FREQUENCY BAND
THE DESIGN AND OPERATION OF TRAPATT DIODES FOR SYSTEMS REQUIREMENTS IN THE l-5GHz FREQUENCY BAND B.H. Newton, M. Pierrepont, C.D. Corbey, M.A. Ayling, J.G. Summers, M. Stace ABSTRACT Trapatt devices and circuits have been designed for use as solid state transmitters for pulse radars in the l-5GHz range. This has been achieved as a result of a device and circuit investigation in which pulse power
PERFORMANCE LIMITS OF PRACTICAL LOW NOISE, HIGH STABILITY GUNN OSCILLATORS