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GB1528901A - Radio signalling systems - Google Patents

Radio signalling systems

Info

Publication number
GB1528901A
GB1528901A GB32227/74A GB3222774A GB1528901A GB 1528901 A GB1528901 A GB 1528901A GB 32227/74 A GB32227/74 A GB 32227/74A GB 3222774 A GB3222774 A GB 3222774A GB 1528901 A GB1528901 A GB 1528901A
Authority
GB
United Kingdom
Prior art keywords
burst
cycles
given
count
further counter
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB32227/74A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to GB32227/74A priority Critical patent/GB1528901A/en
Publication of GB1528901A publication Critical patent/GB1528901A/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G—PHYSICS
    • G07—CHECKING-DEVICES
    • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C9/00—Individual registration on entry or exit
    • G07C9/20—Individual registration on entry or exit involving the use of a pass
    • G07C9/28—Individual registration on entry or exit involving the use of a pass the pass enabling tracking or indicating presence
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
    • G08B25/01—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
    • G08B25/10—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using wireless transmission systems
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Business, Economics & Management (AREA)
  • Emergency Management (AREA)
  • Time-Division Multiplex Systems (AREA)

Abstract

1528901 Selective signalling W D GILMOUR 20 Oct 1975 [20 July 1974] 32227/74 Heading G4H A radio signalling system includes a number of portable tokens each capable of transmitting signals in the form of bursts of carrier frequency separated by modulation pulses, the number of cycles in each burst being characteristic of that token, and a receiver capable of distinguishing between received signals from tokens with different characteristic numbers of cycles in their bursts. In a first embodiment, the cycles in each burst are counted and a most-significant part of the count is compared with a preset value to increment a further counter on equality and decrement it on inequality. If a predetermined number is reached by the further counter, access is given to a secure area. A second embodiment (usable by old people to summon help) differs in that a most-significant part of the count in one burst is compared with the same part for the next burst to control a further counter as before, but instead of access being given to a secure area, an alarm is given and the part-count displayed to identify the person.
GB32227/74A 1975-10-20 1975-10-20 Radio signalling systems Expired GB1528901A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB32227/74A GB1528901A (en) 1975-10-20 1975-10-20 Radio signalling systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB32227/74A GB1528901A (en) 1975-10-20 1975-10-20 Radio signalling systems

Publications (1)

Publication Number Publication Date
GB1528901A true GB1528901A (en) 1978-10-18

Family

ID=10335290

Family Applications (1)

Application Number Title Priority Date Filing Date
GB32227/74A Expired GB1528901A (en) 1975-10-20 1975-10-20 Radio signalling systems

Country Status (1)

Country Link
GB (1) GB1528901A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7811650A (en) * 1978-11-28 1980-05-30 James Arnold Rodrian Automatic animal identification system - uses transceiver and counter contained in portable transponder unit attached to animal
FR2443725A1 (en) * 1978-12-08 1980-07-04 Rodrian James Automatic animal identification system - uses transceiver and counter contained in portable transponder unit attached to animal
WO1982000377A1 (en) * 1980-07-21 1982-02-04 Taylor D A location device
USRE37986E1 (en) 1984-05-30 2003-02-11 The Chamberlain Group, Inc. Coding system for multiple transmitters and a single receiver

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL7811650A (en) * 1978-11-28 1980-05-30 James Arnold Rodrian Automatic animal identification system - uses transceiver and counter contained in portable transponder unit attached to animal
FR2443725A1 (en) * 1978-12-08 1980-07-04 Rodrian James Automatic animal identification system - uses transceiver and counter contained in portable transponder unit attached to animal
WO1982000377A1 (en) * 1980-07-21 1982-02-04 Taylor D A location device
USRE37986E1 (en) 1984-05-30 2003-02-11 The Chamberlain Group, Inc. Coding system for multiple transmitters and a single receiver

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Legal Events

Date Code Title Description
PS Patent sealed
PCNP Patent ceased through non-payment of renewal fee

Effective date: 19931020