Denso Corporation

Nippon Soken, Inc.

Gorou Inoue

Takatoshi Sekizawa

Yuji Sugimoto

Noriaki Okada

Munenori Matsumoto

Akihiro Sasaki

Kentaro Asai

Masahiro Sugiura

Tomoyuki Miyagawa

Hiromichi Naitoh

Syuichi Kono

Hironori Kato

Shinichirou Katou

Masahito Hirayama

A waveform shaping circuit wave-shapes a demodulated signal after FM demodulation to generate a binary value. A smoothing circuit smoothes the demodulated signal to generate a reference voltage. A comparator compares the reference voltage with the demodulated signal to output the binary value. A potential difference limiting circuit determines whether a potential difference between the demodulated signal and the reference voltage exceeds a set voltage. When the potential difference exceeds the set voltage, the potential difference is controlled to a value less than the set voltage. At the initiation of signal reception or after a jamming signal stops, the reference voltage follows the demodulated signal, thus allowing data reception to rapidly begin.

Receiving device for frequency modulated signals with voltage-limited reference input to demodulated signal binarization comparator

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

A transmission system is provided which includes a transmitter working to transmit data on a frame basis and a receiver. If two frames having the same data are inputted in sequence to the receiver, the receiver decides that it is unnecessary to decode a following one of the frames and stops receiving or decoding it. This results in decreases in operation load and power consumption of the receiver.

Frame data transmission system having power save structure

A receiver includes a circuit board and a dielectric antenna. The circuit board has a receiving circuit on a first surface, and a ground pattern on a second surface. The circuit board is disposed close to a rear window of a vehicle so that the ground pattern faces a roof panel. The dielectric antenna extends from an edge of the circuit board toward and along the rear window. As a result, the roof panel capacitively couples with the ground pattern, so that the roof panel becomes imaginary ground. The dielectric antenna functions as a monopole antenna with the imaginary ground. It is not influenced with a metallic material of the vehicle.

Vehicular radio wave receiver and information displaying apparatus with radio wave receiver

Growing community of inventors

Obu, Japan

Gorou Inoue