Remote control security system for automobile issuing a fixed basic code and two variable codes

摘要

A remote control security system includes a remote control unit, a receiving unit, and an operation unit connected to the receiving unit for performing or cancelling an alarm function. A combination code having a basic code and two sets of remedy codes is produced by an encoder. When the receiver has received the signals from the remote control unit, a decoder compares the basic code and the two sets of remedy codes received by the receiver with a reference basic code and two sets of remedy codes generated by the encoder and, if the received and reference codes match, the decoder sends a control signal to the operation unit. One of the remedy codes is varied by a counter once each time the remote control button is pushed and the other is varied by the counter during the time that the button is being pushed.