Patent ID: 11899096
Assignee: DENSO CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  H  B  E | IPC B  G  H

Claim 8:
9. A vehicle system comprising:
a portable device carried by a user; and
a transmission control device mounted on a vehicle and driving a plurality of antennas to detect a position of the portable device relative to the vehicle using a wireless communication between the portable device and the plurality of antennas, the plurality of antennas being arranged at respective positions of the vehicle and having different transmission ranges from one another,
wherein
the transmission control device includes a processor and memory configured to:
control a first transmission antenna to transmit, with use of a carrier wave, a genuine code that activates the portable device and a first burst signal following the genuine code, the first transmission antenna being one of the plurality of antennas; and
control a second transmission antenna to transmit, with use of a carrier wave, a second burst signal having a 180 degrees shifted phase from the first burst signal concurrently with a transmission of the first burst signal from the first transmission antenna, and the second transmission antenna being one of the plurality of antennas and having a transmission range that does not overlap with a transmission range of the first transmission antenna,

the portable device includes a transmission unit,
the transmission unit is configured to transmit information which enables a detection of the position of the portable device relative to the vehicle in response to a reception of the first burst signal followed by the genuine code, and
the transmission unit is configured to not transmit the information which enables the detection of the position of the portable device relative to the vehicle when the first burst signal is not received after a reception of the genuine code.