A communication system includes: a vehicle-mounted communication device and a portable device. The communication device includes: a vehicle transmission unit which transmits a plurality of first signals to the portable device, and a vehicle reception unit which receives a second signal transmitted from the portable device. The portable device includes: a portable device reception unit which receives the first signals, a portable device controller which detects signal intensities of the received first signals, and which compares the signal intensities of the first signals, and a portable device transmission unit which transmits the second signal according to control of the portable device controller. The portable device controller sets an output value of the second signal to a predetermined value when a difference between the compared signal intensities of the first signals is equal to or less than a threshold.

An access system and a method for a vehicle, having at least one vehicle-mounted motion sensor and at least one motion sensor that can be carried by a person, in each case for sensing a single sequence of motions of the person moving outside of the vehicle and carrying the portable motion sensor, an access control unit of the vehicle for locking and/or unlocking at least one door of the vehicle and a controller for comparing the sequence of motions of the person sensed via the vehicle-mounted motion sensor with the sequence of motions of the person sensed via the portable motion sensor, wherein the access control unit can be actuated by the controller as a function of the comparison of the two sequences of motions in such a manner that the access control unit automatically locks or automatically unlocks the at least one door.

An information processing apparatus including a control unit configured to acquire a distance between a vehicle and a user terminal based on position information of the vehicle and position information of the user terminal, and generate a command for setting or releasing a remote immobilizer function and a smart cancel function based on the distance between the vehicle and the user terminal. The remote immobilizer function is a function for remotely setting or releasing an immobilizer of the vehicle. The smart cancel function is a function for stopping radio waves transmitted from the vehicle for communication between the vehicle and a key of the vehicle.

Since two pieces of fraudulently acquired authentication information A are transmitted from a transmission device at relatively short time intervals, a time Tp is relatively short, whereas the two pieces of authentication information A are received by a control device at relatively long time intervals, an elapsed time TMAX is relatively long and this relationship is different from that in a case where there is no fraudulent work. Thus, it is possible to accurately determine whether received authentication information is fraudulently acquired information on the basis of a relationship between a code included in the authentication information received in the control device and a code that is being selected in the control device, and a relationship between first time information and second time information included in the authentication information received in the control device.

A moving device receives a 100% duty measurement signal transmitted from an in-vehicle device. The receive strength of the received measurement signal is divided into unit time, and the average value of the receive strength for each unit time is determined The maximum value and the minimum value of the average value are determined, and the ratio between the maximum value and the minimum value is transmitted to the in-vehicle device as signal strength fluctuation information. The in-vehicle device determines that a communication state is abnormal if it is determined that the fluctuation ratio exceeds a predetermined threshold.

A vehicle communication system (100) comprises a base station (104) positioned in the vehicle (102) and a mobile communication unit (122). The base station (104) comprises a first transmitter for transmitting a signal to the mobile communication unit (122) and a first receiver for receiving an authentication signal from the mobile communication unit (122). The base station (104) is configured to track a position of the mobile communication unit with respect to the vehicle based on a time of flight of a communication between the mobile communication unit and at least the first transmitter and the first receiver, to receive a subsystem status signal relating to performance of a monitored vehicle (102) function and to determine, based on the subsystem status signal, a monitored function status relating to the monitored vehicle (102) function. The base station (104) is also configured to output a status update signal for receipt by the mobile communication unit (122), the status update signal being indicative of the monitored function status. The vehicle communication system (100) is configured to provide a status indication to a user based on the status update signal in dependence on the position of the mobile communication unit (122).

A control unit (40A) includes an operation state determination unit (43) that determines an operating state of a driving source (21) and a communication state determination unit (46) that determines a communication state between an authentication unit (2) and a remote key (4), and the control unit (40A) disables a starting of the driving source (21) by a driving source starting unit (21a) when the control unit (40A) is in an ON state, the operation state determination unit (43) determines that the driving source (21) is in a non-operating state, and the communication state determination unit (46) determines that communication with the remote key (4) is lost.

Aspects of the subject disclosure may include, for example, a device in which a processing system of a remote entry system selects a first circuit from a plurality of circuits of a key remote from the device; wirelessly transmits a first challenge signal to the key, the first challenge signal specifying the first circuit; and wirelessly receives a first response signal from the key, the first response signal having a first response signal power level and a first response signal delay with respect to the first challenge signal. The processing system analyzes the first response signal by comparing the first response signal power level and the first response signal delay respectively with a predetermined first signal power and predetermined first time delay associated with the first circuit; and, in accordance with the comparing, determines whether to enable the entry system. Other embodiments are disclosed.

A circuit device is used in an electronic device including a receiver, a control circuit that performs processing on reception data received by the receiver using a clock signal, a transmitter that transmits transmission data generated by performing processing based on the reception data by the control circuit. The circuit device includes a time-to-digital conversion circuit that measures a time difference between a transition timing of a start signal based on the reception data and a transition timing of a stop signal based on the transmission data or the clock signal, and an output interface that outputs, to the control circuit, a measurement result of the time difference of the time-to-digital conversion circuit.

System and techniques for a secure wireless lock-actuation exchange are described herein. After receiving a request to actuate a lock from a device, a controller can calculate a challenge counter and then perform verification iterations until an end condition is met—which is a failure of a verification iterations or the number of iterations reaches the challenge count. If the verification iterations reach the challenge count (e.g., there are no failed iterations), then the controller actuates the lock. Each iteration includes an exchange between the device and the controller that the device validates by signing a message with a private key shared by the device and the controller. The exchange also includes a freshness value integrated into the device validation to prevent replay attacks.