ALEXANDRIA, Va., July 30 -- United States Patent no. 12,370,978, issued on July 29, was assigned to DENSO Corp. (Kariya, Japan).
"Electronic key system" was invented by Hiroya Yamamoto (Kariya, Japan), Ryusuke Ishikawa (Kariya, Japan) and Kohei Nimura (Kariya, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "An electronic key system installed in a vehicle includes: a first wireless communication controller performing transmission of a predetermined radio signal, as a verification signal, via a first wireless communication to confirm presence or absence of each of a first portable device and a second portable device each of which is usable as an electronic key of the vehicle; a second wireless communicati...