Patent number 8633797 is assigned to
The following quote was obtained by the news editors from the background information supplied by the inventors: "The invention relates in general to security systems which allow operation upon the receipt of a properly coded signal. More particularly, the invention relates to a security system or to a barrier operator system, such as a garage door operator, employing a transmitter and a receiver which communicate via code streams having at least a portion thereof which changes with multiple operation of the device.
"It is well known in the art to provide garage door operators or other barrier operators which include an electric motor connectable through a transmission to a door or other movable barrier which is to be opened and closed. Since many of these systems are associated with residences, as well as with garages, it is important that opening of the barrier be permitted only by one who is authorized to obtain entry to the area which the barrier protects. Some garage door operator systems have in past employed mechanical lock and key arrangements associated with electrical switches mounted on the outside of the garage. While these systems enjoy a relatively high level of security, they are very inconvenient to use for a person because it necessitates them exiting their vehicle in order to send the command to open the garage door. This also may present some danger to people when they exit the relative security of their vehicle if someone may be waiting to do injury to them.
"It is also well known to provide radio-controlled garage door operators which include a garage door operator unit having a radio receiver and a motor connected to be driven from the radio receiver. The radio receiver is adapted to receive radio frequency signals or other electromagnetic signals having particular signal characteristics which, when received, cause the door to be opened. More recently, such transmitter and receiver systems have become relatively more sophisticated in that they use radio transmitters which employ coded transmissions of multiple or three-valued digits, also known as 'trinary bits' or other serial coded transmission techniques. Among these systems are U.S. Pat. No. 3,906,348 to Willmott, which employs a transmitter and receiver system wherein a plurality of mechanical switches may be used to set a stored authorization code.
"U.S. Pat. No. 4,529,980 to Liotine et al. discloses a transmitter and receiver combination for use in a device such as a garage door operator wherein the transmitter stores an authorization code which is to be transmitted to and received by the receiver via a radio frequency link. In order to alter or update the authorization code contained within the transmitter, the receiver is equipped with a programming signal transmitter or light emitting diode which can send a digitized optical signal back to the transmitter where it is stored. Other systems also employing encoded transmissions are U.S. Pat. Nos. 4,037,201, 4,535,333, 4,638,433, 4,750,118 and 4,988,992.
"While each of these devices have provided good security for the user, it is apparent that persons wishing to commit property or person-related crimes have become more sophisticated as well. It is known in the security industry today that devices are being made available that can intercept or steal rolling code.
"What is needed is an economical encoding system which provides good security by using a rolling code, but which enables a user of the system to proceed via a gradually degraded pathway in the event that the receiver detects a signal condition indicative of what might be a lack of security."
In addition to the background information obtained for this patent, VerticalNews journalists also obtained the inventors' summary information for this patent: "The invention relates in general to an electronic system for providing remote security for entry of actuation of a particular device. Such a system may include a transmitter and receiver set, for instance with a hand-held transmitter and a receiver associated with a vehicle such as an automobile or the like. The transmitter, upon signaling the receiver, causing the vehicle to start up or to perform other functions. The system may also be useful in a barrier operator system such as a garage door operator by allowing the garage door to be opened and closed in a relatively secure fashion while preventing persons who may be intercepting the radio frequency signals from being able to, although unauthorized, cause the vehicle to being running or to allow access to the garage.
"The system includes a transmitter generally having means for developing a fixed code and a rolling or variable code. The rolling or variable code is changed with each actuation of the transmitter. The fixed code remains the same for each actuation of the transmitter. In the present system, the transmitter. In the present system, the transmitter includes means for producing a 32-bit frame comprising the fixed portion of the code and a second 32-bit frame comprising the variable portion of the code. The 32-bit rolling code is then mirrored to provide a 32-bit mirrored rolling code. The 32-bit mirrored rolling code then has its most significant bit 'deleted' by setting it to zero. The transmitter then converts the 32-bit fixed code and the mirrored variable code to a three-valued or trinary bit fixed code and a three-valued or trinary bit variable code or rolling code.
"To provide further security, the fixed code and the rolling codes are shuffled so that alternating trinary bits are comprised of a fixed code bit and a rolling code bit to yield a total of 40 trinary bits. The 40 trinary bits are then packaged in a first 20-trinary bit frame and a second 20-trinary bit frame which have proceeding them a single synchronization and/or identification pulse indicating the start of the frame and whether it is the first frame or the second frame. Immediately following each of the frames, the transmitter is placed into a quieting condition to maintain the average power of the transmitter over a typical 100 millisecond interval within legal limits promulgated by the
"Thus, the present system provides important advantages over the previous garage door operator systems and even previous rolling code systems. The system provides a multiple segmented windowed system which provides a valid code window, a second relatively insecure code window in which two successive valid codes must be received and finally a window in which no valid codes are recognized due to the likelihood of the receiver having been stolen.
"It is a principal object of the present invention to provide a security system involving a radio frequency transmitter and receiver wherein multiple security conditions may exist requiring different levels of signal security.
"It is another object of the present invention to provide a secure radio transmitter receiver system which may rapidly and easily decode a relatively large code combination.
"Other advantages of the invention will become obvious to one of ordinary skill in the art upon a perusal of the following specification and claims in light of the accompanying drawings."
URL and more information on this patent, see: Farris,
Keywords for this news article include:
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC
Most Popular Stories
- Software Writers Sought in Indiana
- Miley Cyrus Performs in Undies After Costume Goes Missing
- FBI Helping Ukraine Recover Stolen Billions
- HBO No Go During 'True Detective' Finale
- Uninsured Rate Continues to Fall
- Neil Young Debuts PonoMusic This Week
- Kim Jong Un Elected in Remarkable Unanimous Vote
- Growth Expected if Congress Passes Budget
- 'The Bachelor' Juan Pablo Picks His Love
- Colo. Raises $3.5 Million in Pot Revenue