Patent ID: 7623663
Filing Date: 2009-11-24
Classification: G07C,H04L,Y04S

Abstract:
1. A security system for generating authorizing signals in response to transmitted rolling codes comprising: a transmitter responsive to interaction with a send button for transmitting rolling codes comprising a fixed portion and a rolling portion which varies with each transmission in accordance with a predetermined sequence of rolling portions; a receiver for receiving transmitted rolling codes and for learning the fixed portion and a first rolling portion of the sequence of rolling portions; the receiver being responsive to a received rolling code for generating authorizing signals when the received rolling code comprises the previously learned fixed code portion and a rolling portion within a first predetermined number of rolling portions in the sequence of the learned rolling portion; and the receiver being responsive to a received rolling code for generating authorizing signals when the received rolling code comprises the learned fixed code portion, the rolling code portion is beyond the first predetermined number of rolling portions and is within a second predetermined number of rolling portions of the rolling portion of a most recently received prior rolling code.