An electronic key system (3) that performs ID verification communication to verify an ID of an electronic key (1). The ID verification communication is started by transmission of a wireless signal from a vehicle (2) and performed between the vehicle (2) an...

A DSP tuner (70), which is equipped with an A/D converter (72) and a digital signal processing part (74), is provided to the receiving parts (18, 44) of an in-vehicle equipment and a portable equipment that constitute an in-vehicle equipment remote control...

A DSP tuner (70), which is equipped with an A/D converter (72) and a digital signal processing part (74), is provided to the receiving parts (18, 44) of an in-vehicle equipment and a portable equipment that constitute an in-vehicle equipment remote control...

Once the release switch is operated via the control unit in the car, a vehicle transmitter for the vehicle interior is triggered to send a passivation signal to an existing identification device (radio key device) in the vehicle. This signal prevents its f...

A passive signal discriminator for preventing activation by undesired signals of low power transponder circuits in a keyless entry system. These undesired signals may be noise or interfering signals. An asymmetrical low pass filter is used to determine the...