Abstract: A vehicle system includes a vehicle-mounted device mounted to a vehicle and a portable device portable by a user, and performs a control to the vehicle corresponding to a collation result performed based on a wireless communication established between the vehicle-mounted device and the portable device. The vehicle-mounted device includes a vehicle-mounted transmission unit which simultaneously transmits radio waves having a predetermined phase difference using at least two transmission antennas disposed orthogonal to each other. The portable device includes a triaxial reception antenna receiving the at least two radio waves, and a magnetic field strength detection unit detecting a magnetic field strength on each of three axes of the triaxial reception antenna. One of the vehicle-mounted device or the portable device includes an illicitness determination unit determining, based on the detected magnetic field strength, whether the wireless communication is established through an illicit repeater.

Abstract: A vehicle system includes: an in-vehicle apparatus having a signal transmission unit that transmits different pulse pattern signals from multiple transmitting antennas; and a portable device having a receiving unit that receives the signals. The in-vehicle apparatus or the portable device includes a portable device position identification unit that identifies a position of the portable device according to the signals. The portable device includes a frequency-to-voltage conversion unit that outputs a voltage corresponding to a frequency of each signal. The portable device position identification unit includes: a first storage unit that preliminary stores voltage change patterns corresponding to the frequencies of the signals in relation to positions of the vehicle; and a first position estimation unit that compares the voltage change patterns of the frequency-to-voltage conversion unit with the voltage change patterns in the first storage unit, and estimates the position of the portable device.

Abstract: In an antenna, a first element is connected to a GND of a feeder, on the same plane as a GND of a wireless circuit, and isolated from the GND of the wireless circuit. A second element is on the same plane as the GND of the wireless circuit and a first end connected to the first element and a second end as an open end. The third element has a first end connected to a power source of the feeder and located in a region occupied by the first element perpendicularly to the first element so that its first end source faces down. The fourth element has a first end connected to a second end of the third element and a second end as an open end, is parallel to the first element, and is perpendicular to a line connecting the first and second ends of the second element.

Abstract: A communication device changes an applied voltage output from a voltage circuit, and allows a capacitance measuring device to measure the respective capacitance values of a variable capacitance element before and after a change in the applied voltage. The communication device calculates a voltage correction value for correcting an initial variation of the capacitance value of the variable capacitance element using the respective capacitance values of the variable capacitance element before and after the change in the applied voltage, and respective applied voltage values before and after the change, and a correction voltage for canceling the initial variation in the capacitance value of the variable capacitance element, and outputs the correction voltage from the voltage circuit.

Abstract: A wireless communication system includes a mobile device carried by a user and an in-vehicle apparatus equipped to a vehicle and communicatively connected with the mobile device. The in-vehicle apparatus includes a transmission unit, a transmission control unit, a reception determination unit, and a position determination unit. The transmission unit transmits low-frequency band request signals generated by spread modulating transmission data with predetermined spreading factors. The transmission control unit controls the transmission unit to generate and transmit first and second request signals having first and second attainable ranges by spread modulation using first and second spreading factors, respectively. The reception determination unit performs reception determination to response signal transmitted from the mobile device in response to the request signal.

Abstract: A wireless communication system includes a mobile device carried by a user and an in-vehicle apparatus equipped to a vehicle and communicatively connected with the mobile device. The in-vehicle apparatus includes a transmission unit, a transmission control unit, a reception determination unit, and a position determination unit. The transmission unit transmits low-frequency band request signals generated by spread modulating transmission data with predetermined spreading factors. The transmission control unit controls the transmission unit to generate and transmit first and second request signals having first and second attainable ranges by spread modulation using first and second spreading factors, respectively. The reception determination unit performs reception determination to response signal transmitted from the mobile device in response to the request signal.

Abstract: In a smart system, an onboard system transmits a request signal. A portable device receives the request signal. An LF demodulation portion demodulates the request signal to acquire request data and returns an answer signal based on acquisition of the request data. The onboard system receives the answer signal and performs smart drive based on reception of the answer signal. The onboard system also transmits a specified counter-RA signal. A switching circuit of the portable device outputs the received counter-RA signal to a modulation portion while bypassing the LF demodulation portion. The modulation portion performs RF modulation using the counter-RA signal to acquire a counter-RA modulation signal and transmits the counter-RA modulation signal. When receiving the counter-RA modulation signal, the onboard system determines whether to allow or disallow the smart drive based on delay time of timing to receive the counter-RA modulation signal with reference to timing to transmit the counter-RA signal.

Abstract: An onboard apparatus control system is disclosed. The onboard apparatus control system includes a portable apparatus and an in-vehicle apparatus which controls an onboard apparatus according to position of the portable apparatus. From multiple transmitting antennae, the in-vehicle apparatus transmits pulse pattern signals with different transmission frequencies at an overlapping timing, so that the pulse pattern signals are radio waves whose intensities are changed stepwise according to different patterns. The portable apparatus receives the radio waves transmitted from the multiple transmitting antennae. The position of the portable apparatus with respect to the vehicle is determined based on a combined pattern of the received pulse pattern signals, which a receiving unit is to receive at location with respect to the vehicle.

Abstract: In a wireless communication apparatus, when a first switch electrically connects a second antenna to an impedance matching circuit and a second switch electrically connects a first antenna to a reception circuit, a frequency signal output from an oscillator of the reception circuit is received by the second antenna and applied to the impedance matching circuit. Then, a controller controls the impedance of the impedance matching circuit so as to bring a RSSI voltage output from a signal strength detection circuit of the reception circuit into agreement with a reference RSSI voltage, thereby bringing the reference frequency of the first antenna into agreement with a reference frequency.

Abstract: A wireless communication system has an in-vehicle system disposed in a vehicle and a portable device carried by a user, where the in-vehicle system and the portable device are communicably coupled. The in-vehicle system uses a transmitter for transmitting a request signal to the portable device in LF wave band, and the transmitter includes: a spread process unit for spread-modulating predetermined LF data by a spread spectrum method and for generating a spread data signal; and a modulation driver unit for converting the spread data signal to a modulation signal in the LF wave band and for outputting such modulation signal as a request signal to an antenna after amplifying the modulation signal.

Abstract: A matching circuit, connected to a receiving antenna and to the input of a receiving circuit, incorporates a variable capacitor that is adjustable for tuning the resonance frequency of the antenna to a desired reception frequency. In an automatic tuning mode of operation, an oscillator signal of different frequency from the reception frequency is applied to induce resonance of the antenna and matching circuit, and the variable capacitor is adjusted until an output signal level from the receiving circuit attains a predetermined value which has been stored beforehand in a memory and which corresponds to a condition whereby the antenna resonance frequency corresponds to the reception frequency and impedance matching exists between the antenna and receiving circuit.

Abstract: An onboard apparatus control system is disclosed. The onboard apparatus control system includes a portable apparatus and an in-vehicle apparatus which controls an onboard apparatus according to position of the portable apparatus. From multiple transmitting antennae, the in-vehicle apparatus transmits pulse pattern signals with different transmission frequencies at an overlapping timing, so that the pulse pattern signals are radio waves whose intensities are changed stepwise according to different patterns. The portable apparatus receives the radio waves transmitted from the multiple transmitting antennae. The position of the portable apparatus with respect to the vehicle is determined based on a combined pattern of the received pulse pattern signals, which a receiving unit is to receive at location with respect to the vehicle.

Abstract: When a demodulated signal of a radio signal in Ch1 transmitted from a TPMS transmitter is acquired, a control IC controls the frequency of a signal inputted from a PLL circuit to a mixer into a frequency for converting a TPMS radio signal into an intermediate frequency signal of a specific frequency. When the demodulated signal of the radio signal transmitted from a portable unit through two frequency channels is acquired, the control IC determines a channel whose state of communication is favorable from between Ch2 and Ch3, and controls the signal frequency for conversion into a frequency for converting a keyless radio signal in the determined channel into an intermediate frequency signal.

Abstract: When a vehicle door locking operation is conducted, an in-vehicle device checks the vehicle compartment to determine whether a mobile unit exists in the vehicle compartment. When the in-vehicle device receives a response from the mobile unit indicating its presence in the compartment, the in-vehicle device receives a response from the mobile unit, prohibits the door from locking, and activates a buzzer. The mobile unit thus can be prevented from being locked in the vehicle compartment. When the mobile unit receives the search signal, it sounds its buzzer, thereby making it possible to further indicate its location within the compartment.

Abstract: In a wireless communication apparatus, when a first switch electrically connects a second antenna to an impedance matching circuit and a second switch electrically connects a first antenna to a reception circuit, a frequency signal output from an oscillator of the reception circuit is received by the second antenna and applied to the impedance matching circuit. Then, a controller controls the impedance of the impedance matching circuit so as to bring a RSSI voltage output from a signal strength detection circuit of the reception circuit into agreement with a reference RSSI voltage, thereby bringing the reference frequency of the first antenna into agreement with a reference frequency.

Abstract: A matching circuit, connected to a receiving antenna and to the input of a receiving circuit, incorporates a variable capacitor that is adjustable for tuning the resonance frequency of the antenna to a desired reception frequency. In an automatic tuning mode of operation, an oscillator signal of different frequency from the reception frequency is applied to induce resonance of the antenna and matching circuit, and the variable capacitor is adjusted until an output signal level from the receiving circuit attains a predetermined value which has been stored beforehand in a memory and which corresponds to a condition whereby the antenna resonance frequency corresponds to the reception frequency and impedance matching exists between the antenna and receiving circuit.

Abstract: An electronic key system includes an in-vehicle unit mounted in a vehicle and a portable unit. When a user leaves the vehicle, the in-vehicle unit requests information on a relative position of the vehicle relative to a landmark object near the vehicle from a vehicle navigation device and transmits received relative position information to the portable unit. The portable unit stores the received relative position information, and notifies of the stored relative position information according to a user's operation.

Abstract: In a certification system, a smart security controller transmits to a portable terminal a designation request signal for which a response frequency is designated. In a case where any signal cannot be received within a preset allowable time period after the transmission of the designation request signal, the smart security controller transmits a designation request signal whose response frequency has been altered to a different frequency. The portable terminal selects the response frequency designated by the designation request signal, and transmits a reception response signal to the smart security controller at the selected response frequency. Accordingly, the response signal can be prevented from becoming unreceivable on account of the radio interference of the response signal.

Abstract: When a door locking operation is conducted in a vehicle, an in-vehicle device executes a vehicle compartment checking to check whether a mobile unit exists in the vehicle compartment. When the in-vehicle device receives a response from the mobile unit, the in-vehicle device transmits a search signal to the mobile unit, prohibits the door locking, and activates a buzzer, etc. The mobile unit can be prevented from being blocked in a vehicle compartment. When the mobile unit receives the search signal, it blows the buzzer, thereby making it possible to indicate the location of its existence.

Abstract: A mobile unit for an electronic key system includes an LF receiver unit that receives a radio signal transmitted from an in-vehicle device by an electric wave of an LF band, a UHF transmitter unit that transmits a radio signal to the in-vehicle unit by an electric wave of a UHF band. The mobile unit also includes a UHF receiver unit that receives a search signal transmitted from another mobile unit by an electric wave of the UHF band, and a buzzer that notifies outside existence thereof when the search signal is received by the UHF receiver unit. The UHF transmitter unit can transmit the search signal to the mobile unit in addition to the radio signal to the in-vehicle device.