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. 17, 1987
Filed:
Jun. 07, 1985
Norio Numata, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A cordless telephone comprises a base unit and a plurality of remote units. The remote units are respectively adapted to establish radio communication at separate times with the base unit. Each remote unit generates a particular code in a particular format that includes at least one interval in which the particular code is present and at least one interval from which the particular code is absent. The particular code and particular format of each remote unit are different from those of the other remote units. A transmitter in each remote unit transmits the particular code of that unit in the particular format thereof to the base unit. The particular formats are such that the transmission of each particular code periodically corresponds to non-transmission of all of the other particular codes of the remote units. The particular codes can thus periodically be received by the base unit without interference caused by transmission of the other particular codes. The base unit echoes the particular code transmitted by a selected one of the remote units, and each of the remote units detects whether or not its own particular code matches the particular code echoed by the base unit. In response to such a match, a communication channel is established between the base unit and the one of the remote units in which the match occurs. The communication channel while established precludes establishment of a communication channel between the base unit and any of the other remote units.