Denso Corporation

Nippon Soken, Inc.

Hiromichi Naitoh

Masahiro Sugiura

Akira Takaoka

Kenichiro Sanji

Noriaki Okada

Munenori Matsumoto

Yuuji Kakuya

Masakazu Ikeda

Akihiro Taguchi

Kenichirou Sanji

Tomokazu Miyashita

Gorou Inoue

Ryozou Fujii

Masashi Urabe

Mitsugi Ootsuka

Hironori Katoh

Shinichirou Katou

An antenna device includes a ground plate which is a flat plate-shaped conductor member, an opposing conductive plate which is a flat plate-shaped conductor member installed at a predetermined distance from the ground plate and is electrically connected to a power supply line, and a plurality of short-circuit pins for electrically connecting the opposing conductive plate and the ground plate. One end of a plurality of short-circuit pins extends to a conductive plate plane, which is a plane including the opposing conductive plate, and the other end of the plurality of short-circuit pins extends to the ground plate plane, which is a plane including the ground plate. One or more of the plurality of short-circuit pins connect the opposing conductive plate and the ground plate.

Antenna device

In a wireless communication system, a portable device transmits a first signal spread based on a reference period indicated by a synchronization signal transmitted from an in-vehicle device and transmits a second signal spread based on an operation by a user. The in-vehicle device sets a search period based on a variation range in a delay time from when the synchronization signal is transmitted to when the spread first signal is transmitted and sets a residual period that starts at an ending point of the search period and ends at an ending point of the reference period when a starting point of the reference period is set at a starting point of the search period. When the in-vehicle device fails in a synchronous acquisition for the search period, the in-vehicle device performs a synchronous acquisition process for the residual period.

Wireless communication system

A receiving device for spread spectrum communication includes a phase determining unit and a data demodulating unit. The receiving device receives a signal spread and modulated with first spreading code. The phase determining unit calculates a cross correlation between the received signal and a second spreading code and determines a phase P(0) of the received signal based on the cross correlation. The data demodulating unit synchronizes the phase P(0) and the first spreading code and despreads and demodulates the received signal with the first spreading code. The number of components in each of the first spreading code and the second spreading code is an integer greater than or equal to 2.

Receiving device for spread spectrum communication

When a demodulated signal of a radio signal in Chtransmitted 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 Chand Ch, 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.

Vehicle control system

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.

Electronic key system and method

Growing community of inventors

Okazaki, Japan

Hiromichi Naitoh