Remote control system for car-mounted device

A remote control system for a car-mounted device, comprising:

• a portable unit;
• and
• an in-car unit for controlling a certain operation in a car by communication with said portable unit;
• said portable unit including:
• function judgment means for judging whether a keyless function or a smart function is used based on an inquiry signal from an operation detection part or said in-car unit;
• amplification means for controlling transmission power of a transmission part in response to a result of judgment obtained at said function judgment means;
• and
• system clock generation means for controlling a transmission band of the transmission part in response to a result of judgment obtained at said function judgment part;
• said in-car unit including:
• in-car function judgment means for judging whether the keyless function or the smart function is used based on a response signal from said portable unit;
• and
• in-car system clock generation means for controlling a receiving band of an in-car receiving part in response to a result of judgment obtained at said in-car function judgment means.