The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 01, 1996
Filed:
Apr. 16, 1993
Osten Makitalo, Uttran, SE;
Bo Olsson, Haninge, SE;
Televerket, Farsta, SE;
Abstract
The invention relates to a method and an arrangement for improving the communication between a base station and a number of mobile units belonging to it in a microcell system. In greater detail, the invention has the aim of reducing the fading which is a problem when the mobile units are moving slowly or are standing still. According to the invention, the problem is solved by introducing diversity on the downlink in the system. The antenna pattern of the base station is turned so that a wave pattern varying with time is produced with spatially separated fading points. The communication preferably utilizes time-division multiple access (TDMA), the turning of the antenna pattern being effected step by step between suitable time slots, preferably between TDMA frames. The turning of the antenna pattern is advantageously produced by controlling a sectoral antenna (7, 7'). In a preferred embodiment, the directional antenna (7') comprises an active element (10') in the form of a half-wave dipole surrounded by a dielectric (11) which, in turn, is enclosed in a cylinder which is made up of a number of passive elements (9') insulated from one another. The turning of the antenna pattern of the directional antenna is produced by electrically switching the passive elements.