Advanced embedded code hopping system having master fixed code encryption

摘要

A system for monitoring and controlling an area comprising a controller for controlling system operational functions; at least one remote-control transmitter for transmitting system commands to the controller in a code word having a fixed word and a hopping word therein; the fixed word comprising at least one fixed data bit and the hopping word comprising at least one changing data bit, wherein the hopping word changes its binary value from transmission to transmission of the system commands; and, means for scrambling bits of the fixed word and bits of the hopping word within the code word.