Abstract: In a door control system, a reservation signal is transmitted when a user operates a mobile device and reserves opening a door, a control device transmits a reservation acceptance signal and starts transmitting a response request signal upon receipt of the reservation signal. When the mobile device receives the reservation acceptance signal, a mobile device memory stores information indicating that the reservation is accepted and authorized and a notification unit notifies the user of authorization. When the mobile device receives the response request signal, the mobile device transmits a response signal including the stored information indicating authorization. When the control device receives the response signal including the information indicating authorization in response to the response request signal, a controller performs at least one of unlocking or opening the door.

Abstract: A vehicle communication system includes a vehicle-mounted device and a portable device. In the vehicle communication system, a transmission unit transmits a first to third radio signals having intensities weaker in this order, a measurement unit measures an intensity of each of the radio signals, and a determination unit that determines whether an intensity difference between any two of the radio signals among the radio signals measured by the measurement unit is larger than a threshold value. Control of a target mounted on the vehicle is permitted if the intensity difference is larger than the threshold value.

Abstract: In a door control system, a reservation signal is transmitted when a user operates a mobile device and reserves opening a door, a control device transmits a reservation acceptance signal and starts transmitting a response request signal upon receipt of the reservation signal. When the mobile device receives the reservation acceptance signal, a mobile device memory stores information indicating that the reservation is accepted and authorized and a notification unit notifies the user of authorization. When the mobile device receives the response request signal, the mobile device transmits a response signal including the stored information indicating authorization. When the control device receives the response signal including the information indicating authorization in response to the response request signal, a controller performs at least one of unlocking or opening the door.

Abstract: A vehicle communication system includes a vehicle-mounted device and a portable device. In the vehicle communication system, a transmission unit transmits a first to third radio signals having intensities weaker in this order, a measurement unit measures an intensity of each of the radio signals, and a determination unit that determines whether an intensity difference between any two of the radio signals among the radio signals measured by the measurement unit is larger than a threshold value. Control of a target mounted on the vehicle is permitted if the intensity difference is larger than the threshold value.

Abstract: A communication system has a first communication device, and a second communication device conduct wireless communication with the first communication device. The first communication device has a first transmitter that transmits a signal to the second communication device, and a first transmission controller that controls the first transmitter. The second communication device has a first receiver that receives the signal from the first communication device, a first reception controller that controls the first receiver, a signal processor that processes the signal received by the first receiver, and a determination part that determines whether the signal received by the first receiver is a normal signal. When transmitting a predetermined first signal, the first transmission controller divides the first signal into a plurality of segments to change a transmission frequency of the first transmitter in units of segments.

Abstract: A communication system has a first communication device, and a second communication device that conducts wireless communication with the first communication device. The first communication device has a first transmitter that transmits a signal to the second communication device, and a first transmission controller that controls the first transmitter. The second communication device has a first receiver that receives the signal from the first communication device, a measurement part that measures a reception intensity of the signal received by the first receiver, and a determination part that determines whether the signal received by the first receiver is a normal signal. The first transmission controller divides a predetermined portion of a predetermined signal into a plurality of portions when transmitting the predetermined signal.

Abstract: A vehicle portable device that locks and unlocks a door of a vehicle by remote control has a case that accommodates a mechanical key operable to lock and unlock the door of the vehicle therein, and having an accommodation part in which the mechanical key is inserted in a predetermined insertion direction, a first engagement part that engages with a second engagement part of the mechanical key, and a retaining member in which the first engagement part is formed. The retaining member is supported in the case while being rotatable about a first support point. An external force is provided on the retaining member so as to rotate the retaining member in a first rotating direction. When the mechanical key is accommodated in the accommodation part, an exposed portion of the mechanical key is partially exposed from the case.

Abstract: A vehicle portable device that locks and unlocks a door of a vehicle by remote control has a case that accommodates a mechanical key operable to lock and unlock the door of the vehicle therein, and having an accommodation part in which the mechanical key is inserted in a predetermined insertion direction, a first engagement part that engages with a second engagement part of the mechanical key, and a retaining member in which the first engagement part is formed. The retaining member is supported in the case while being rotatable about a first support point. An external force is provided on the retaining member so as to rotate the retaining member in a first rotating direction. When the mechanical key is accommodated in the accommodation part, an exposed portion of the mechanical key is partially exposed from the case.