Secure self learning system

• US 6,166,650 A
• Filed: 06/03/1997
• Issued: 12/26/2000
• Est. Priority Date: 05/29/1991
• Status: Expired due to Fees

• Current Assignee: Microchip Technology Incorporated
• Original Assignee: Microchip Technology Incorporated
• Inventors: Bruwer, Frederick
• Primary Examiner(s): Holloway, III, Edwin C.
• Application Number:
  US08/868,131
• Time in Patent Office: 1,302 Days
• Field of Search: 340/825.31, 340/825.22, 340/825.69, 340/825.72, 340/426, 380/21, 380/23, 380/262, 380/274, 341/176
• US Class Current: 340/5.26
• CPC Class Codes: G07C 2009/0023 with encription of the transmittted data signal
• CPC Class Codes: G07C 2009/00253 dynamically, e.g. variable code - rolling code
• CPC Class Codes: G07C 2009/00769 with data transmission performed by wireless means
• CPC Class Codes: G07C 2009/00928 for garage doors
• CPC Class Codes: G07C 2209/06 Involving synchronization or resynchronization between transmitter and receiver; reordering of codes
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks
• CPC Class Codes: G07C 9/00817 where the code of the lock can be programmed
• CPC Class Codes: G07C 9/00857 where the code of the data carrier can be programmed
• CPC Class Codes: H04L 2209/34 Encoding or coding, e.g. Huffman coding or error correction
• CPC Class Codes: H04L 2209/80 Wireless
• CPC Class Codes: H04L 2209/84 Vehicles
• CPC Class Codes: H04L 9/0869 involving random numbers or seeds

Abstract

A method and system for the remote control of devices having a secure self learn capability. The system includes an encoder and a decoder, the encoder encoding variable information including a user key using a non-linear algorithm to produce an encoded value transmitted to the decoder, the decoder decoding the value using the same algorithm. In a learning mode a new encoder is to be added to the system. The new encoder produces an encoded value using a key generation seed. The decoder, upon receiving the encoded key generation seed, produces a decoding key based upon the decoded key generation seed. The decoding key is stored in the decoder memory allowing valid recognition of the new encoder in a secure manner.

Claims

1. A method of operating a decoder which includes the steps of:

storing first information and a key generation routine;

setting the decoder into a learning mode by activating a decoder learning mode activation means physically remote or detached from the decoder;

receiving second information from an encoder; and

calculating a key using the second information, which has been received, the first information, which has been stored during manufacturing, and the key generation routine.

2. An access control system comprising:

an encoder;

a decoder;

wherein the encoder comprises;

a memory that stores a key during manufacturing, the key being generated using first information, second information, and a key generation routine; and

a memory that stores the second information;

wherein the decoder comprises;

a memory that stores a key generation routine and the first information during manufacturing;

a leaning mode activation circuit adaptable for setting the decoder into a learning mode, comprising;

a circuit to activate the encoder to transmit the second information to the decoder during learning;

a circuit to activate the decoder to receive the second information during learning; and

a circuit to calculate, during learning, a key in the decoder using the second information, which has been received, the first information, which has been stored during manufacturing, and the key generation routine; and

wherein the learning mode activation circuit is physically remote from the encoder and the decoder.

3. A method of operating an access control system, comprising the steps of:

storing a key in an encoder during manufacturing, the key being generated using first information, second information, and a key generation routine;

storing the second information in the encoder;

storing a key generation routine and the first information in a decoder during manufacturing;

activating a learning mode activation circuit, wherein the learning mode activation circuit is physically remote from the encoder and the decoder;

transmitting the second information from the encoder to the decoder in response to the learning mode activation circuit being activated;

receiving the second information by the decoder; and

calculating a key in the decoder using the second information, which has been received, the first information, which has been stored during manufacturing, and the key generation routine.