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:
Jul. 17, 2007
Filed:
Oct. 05, 2001
Osamu Hirota, Yokohama, JP;
Yasuharu Shimizu, Tokyo, JP;
Masaki Sohma, Yokohama, JP;
Osamu Hirota, Kanagawa, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A method and system for distributing a key is provided which make use of effects of noise caused at the time of transmitting or receiving a signal to send a key. A transmission signal is amplified at a plurality of stages while the relationship between the transmission signal and noise is being maintained at a level enough to satisfy predetermined criteria for security measures against eavesdropping activities, and the key is sent over a long distance. The aforementioned operation makes it possible to transmit or distribute a key over a long distance while maintaining the relationship between the transmission signal and noise at a level enough to satisfy the criteria for security measures against eavesdropping activities.