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:
Mar. 20, 1990
Filed:
Dec. 08, 1987
Jacques Mainardi, Lievin, FR;
Alsthom, Paris, FR;
Abstract
Information is transmitted at microwave frequencies, the ground station being connected to a waveguide (25) and the station aboard a railway vehicle being connected to an antenna (26). Each station comprises a microwave generator (19) supplying a carrier, transmitters (3 through 7) supplying subcarriers, receivers (28 through 32) and a pilot generator (1). The carrier and subcarrier frequencies are multiples of the pilot frequency and the frequency difference between adjacent subcarriers equals the pilot frequency. A transmitter mixer (MTX) receives the carrier and the subcarriers and is connected to a circulator (24), itself linked to the waveguide (25) in the ground station and to the vehicle station antenna. A receiver mixer (MRX) is connected via a filter (23) to the circulator (24) and receives the carrier from the microwave generator; the latter mixer is connected to the receivers (28 through 32) to which it sends the subcarriers transmitted by the other station.