US Patent 7135787 Self-contained keyless entry system to prevent lockout from restricted-access spaces

The disclosed technology can be used to develop systems and perform methods in which movements (e.g., manipulations of a door handle) associated with a locking element can be detected based on a sequence of signal interruptions caused by these movements and such sequence of signal interruptions can further serve as a basis for identifying an authorized user and as a basis for actuating the locking element to enable the authorized user to gain access to a restricted-access space defined within an enclosure (e.g., an automobile, a boat, an aircraft, a building, a container, a cabinet, etc.).