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. 04, 1983
Filed:
Jun. 08, 1981
Akira Matsumura, Yokosuka, JP;
Nissan Motor Company, Limited, Kanagawa, JP;
Abstract
A communication system for automotive vehicles includes a fixed unit for transmitting an area signal at all times and information signals when requested and a mobile unit mounted on an automotive vehicle for receiving the area signal when the automotive vehicle passes through a communications area and for then transmitting a request signal to receive the information signals from the fixed unit. Since the electric field strength transmitted from the fixed unit is predetermined to be higher than that transmitted from a mobile unit in the case where two threshold levels for electric field strengths transmitted from both the units are equal to each other, it is possible to maintain a stable communications between both the units, even if electric field strength received by the mobile unit drops for some or other.