Electronic security system with two-way communication between lock and key

• US 4,779,090 A
• Filed: 08/06/1986
• Issued: 10/18/1988
• Est. Priority Date: 08/06/1986
• Status: Expired due to Fees

• Current Assignee: David A. Tenenbaum, Isaiah B. Micznik, Jeffrey Tenenbaum
• Original Assignee: David A. Tenenbaum, Isaiah B. Micznik, Jeffrey Tenenbaum
• Inventors: Tenenbaum, Jeffrey, Tenenbaum, David A., Micznik, Isaiah B.
• Primary Examiner(s): Weldon, Ulysses
• Application Number:
  US06/893,648
• Time in Patent Office: 804 Days
• Field of Search: 361/172, 70/256, 70/278, 380/3, 235/382, 235/382.5, 340/572, 340/825.3, 340/825.31, 340/825.34, 340/825.32, 340/825.64, 340/825.72
• US Class Current: 340/5.26
• CPC Class Codes: G07C 9/00904 for hotels, motels, office buildings or the like
• CPC Class Codes: G07C 9/28 the pass enabling tracking or indicating presence
• CPC Class Codes: G07C 9/29 the pass containing active electronic elements, e.g. smartcards

Abstract

An electronic security system having a locked and at least one unlocked state and comprising at least one electronic access controller and at least one electronic key. The electronic security system employs a predetermined, distinctive, first code stored in memories in each access controller and key, and each electronic key stores a predetermined second code consisting of a number part and an associated time delay part. The number parts of all second codes are also stored in the access controller memory.

Claims

1. A security system for controlling access through an entry point of an area or a system, said entry point having a locked state and one or more unlocked states, each said unlocked state allowing different access through said entry point, said system comprising:

an access controller at said entry point, said access controller comprising;

a memory storing a first code and one or more second codes;

a first electromagnetic wave receiver for receiving electromagnetic energy modulated by codes and producing first signals containing the information in said codes in response thereto,

first comparison means adapted to cause said security system to change from said locked state to one of said one or more unlocked states upon proper comparison of the information in codes contained in said first signals with the information in one of said one or more second codes, said one of said one or more unlocked states being a function of said second code that properly compares with the information in the codes contained in said first signals; and

a first transmitter for transmitting an unmodulated activation signal followed by a signal modulated by said first code; and

one or more electronic keys, each of said one or more electronic keys comprising;

a memory storing said first code and a designated one of said second codes;

a second electromagnetic energy receiver for receiving electromagnetic energy modulated by codes and producing second signals containing the information in said modulating codes in response thereto;

second comparison means for comparing the information in portions of said modulating codes contained in said second signals and portions of said stored first code;

a second transmitter for transmitting a signal modulated by said designated one of said one or more second codes upon the occurrence of proper comparison of the information in portions of modulating codes and portions of said stored code by said second comparison means;

a source of electrical power;

a power switch connected to said memory, said second electromagnetic energy receiver, said second comparison means, said second transmitter and said source of electrical power for selectively coupling electric power from said source of electric power to said memory, said second electromagnetic energy receiver, said second comparison means and said second transmitter; and

a passive trigger receiver for receiving said unmodulated activation signal and triggering said power switch to supply electric power to said memory, said second electromagnetic energy receiver, said second comparison means and said second transmitter, upon receipt of said unmodulated activation signal,

whereby each of said one or more electronic keys receives said unmodulated activation signal, switches on and transmits a signal modulated by its designated second code after receiving a signal modulated by the first code and properly comparing the information in a portion of the received first code with a portion of the stored first code, said access controller being operative to receive the signal transmitted by said one or more electronic keys, to compare the received designated second code with the stored one or more second codes, and to enter one of said one or more unlocked states upon the occurrence of a proper comparison of the received designated second code and one of the stored one or more second codes, said one of said one or more unlocked states being a function of said designated second code.

2. The security system of claim 1, wherein said unlocked states are hierarchical.

3. The security system of claim 1, wherein said electronic lock further comprises actuable switch means, said switch means producing a signal that causes said first transmitter to transmit said unmodulated activation signal.

4. The security system of claim 1, wherein said first signal and said signal transmitted by said second transmitter are amplitude modulated signals.

5. The security system of claim 1, wherein the electromagnetic energy is radio frequency energy.

6. The security system of claim 1, wherein said first transmitter includes means for periodically transmitting said unmodulated signal followed by said signal modulated by said first code.

7. The security system of claim 1, further comprising:

an actuable switch means; and

a mode selection means having first and second modes connected to said first transmitter and said actuable switch means for causing said first transmitter to transmit said unmodulated activation signal followed by said signal modulated by said first code upon actuation of said actuable switch means when in said first mode, and for causing said first transmitter to periodically transmit said unmodulated signal followed by said signal modulated by said first code when in said second mode.

8. The security system of claim 1, further comprising:

a power deactuation means connected to said power switch for receiving electric power from said source of electric power for triggering said power switch to cut off the supply of electric power to said memory, said second electromagnetic energy receiver, said second comparison means and said second transmitter a predetermined period of time after said power switch is triggered to supply electric power.

9. A security system having a locked state and an unlocked state, comprising:

an electronic lock comprising;

a memory storing a first code and one or more second codes, each of said one or more second codes comprising a number part and a delay part;

a first electromagnetic wave receiver for receiving electromagnetic energy modulated by codes and producing first signals containing the information in said codes in response thereto,

first comparison means adapted to cause said security system to change from said locked state to said unlocked upon proper comparison of the information in codes contained in said first signals with one of said one or more second codes, and

a first transmitter for transmitting a signal followed by a signal modulated by said first code; and

one or more electronic keys, each of said one or more electronic keys comprising;

a memory storing said first code and a designated one of said second codes;

a second electromagnetic energy receiver for receiving electromagnetic energy modulated by codes and producing second signals containing the information in said modulating codes in response thereto;

second comparison means for comparing the information in portions of said modulating codes contained in said second signals and portions of said stored first code;

a second transmitter for transmitting a signal modulated by said designated one of said one or more second codes upon the occurrence of proper comparison of the information in portions of modulating codes and portions of said stored code by said second comparison means; and

a time delay means connected to said memory, said second comparison means and said second transmitter for delaying said second transmitter for a predetermined period of time after the occurrence of proper comparison of the information in portions of modulating codes and portions of said stored first code, said predetermined period of time corresponding to said delay part of said designated one of said one or more second codes,

whereby one of said one or more electronic keys transmits a signal modulated by its designated second code after receiving a signal modulated by the first code and properly comparing the information in a portion of the received first code with a portion of the stored first code, said electronic lock being operative to receive the signal transmitted by said electronic key, to compare the received designated second code with the stored one or more second codes, and to enter the unlocked state upon the occurrence of a proper comparison of the received designated second code and one of the stored one or more second codes.

10. The security system of claim 9, wherein said time delay part of each of said one or more second codes is distinct, whereby each of said one or more second codes is distinct, whereby each of said one or more electronic keys corresponding to each of said designated one of said one or more second codes delays its response by different times.

11. The security system of claim 9, wherein said first comparison means and said second comparison means are programmed microprocessors.

12. A security system having a locked state and an unlocked state comprising:

an electronic lock comprising;

a memory storing a first code and one or more second codes;

a first electromagnetic wave receiver for receiving electromagnetic energy modulated by codes and producing a first signal containing the information in said codes in response thereto;

a first microprocessor adapted to generate a first random number and to cause said security system to change from said locked state to said unlocked state after deciphering said first signal and upon the occurrence of proper comparison of the information in codes contained in said first signal with one of said one or more second codes; and

a first transmitter for transmitting a second signal modulated by a third code encoded according to said first random number and said first code;

one or more electronic keys, each of said one or more electronic keys comprising;

a memory for storing said first code and a designated one of said one or more second codes;

a second electromagnetic wave receiver for receiving electromagnetic energy modulated by codes and producing third signals containing the information in said modulating codes in response thereto;

a second microprocessor for producing a second random number and for deciphering the codes contained in said third signals and comparing the information in portions of said deciphered codes contained in said third signal and portions of said stored first code; and

a second transmitter for transmitting a signal modulated by a fourth code encoded according to said second random number and said designated one of said one or more second codes upon the occurrence of proper comparison by said second microprocessor,

whereby each of said one or more electronic keys transmits a signal modulated by a fourth code encoded according to said second random number and said designated one of said one or more second codes and properly comparing the information in the received first code with the stored first code, the electronic lock receiving the signal transmitted by said one of said one or more electronic keys, comparing the received distinct fourth code with the stored one or more second codes, and entering the unlocked state upon a proper comparison of the received designated second code and one of said stored one or more second codes.

13. The security system of claim 12, wherein the second random number produced by said electronic key is equal to the first random number generated by said access controller.

14. The security system of claim 12, wherein the access controller further comprises a third transmitter for transmitting an uncoded actuation signal, and each of said one or more electronic keys further comprises a passive receiver and an electrical power switch connected thereto, to receive and respond to the activation signal by causing electrical power to be supplied to the remainder of said electronic key.

15. The security system of claim 12, wherein said third code is encoded by intermixing digits from said first random number and said first code according to a predetermined pattern.

16. The security system of claim 15, wherein said fourth code is encoded by intermixing digits from said second random number and said designated one of said one or more second codes according to a predetermined pattern.

17. The security system of claim 12, wherein the electromagnetic energy is radio frequency energy.