System for detecting individuals or objects passing through an entrance-exit of a defined space

• US 20040070501A1
• Filed: 08/28/2003
• Published: 04/15/2004
• Est. Priority Date: 03/08/2001
• Status: Active Grant

• Current Assignee: EM Microelectronic - Marin SA (The Swatch Group AG)
• Original Assignee: EM Microelectronic - Marin SA (The Swatch Group AG)
• Inventors: Roz, Thierry, Desjeux, Olivier, Degrauwe, Marc
• Granted Patent: US 7,026,924 B2
• Time in Patent Office: Days
• US Class Current: 340/572.1
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G07B 15/02 taking into account a variable factor such as distance or time, e.g. for passenger transport, parking systems or car rental systems G07B15/06 takes precedence; taximeters G07B13/00; parking meters per se G07F17/24; car rental systems per se G07B15/00
• CPC Class Codes: G07C 9/00 Individual registration on entry or exit
• CPC Class Codes: G07C 9/28 the pass enabling tracking or indicating presence

Abstract

There is disclosed a system for detecting the passage of persons or objects through an entry-exit (4) to a delimited space (2), including (i) a detection device including transmission means (8) for transmitting different first and second electromagnetic signals (a, b) in respectively first and second communication regions (A, B) spatially separated from each other and partially overlapping, (ii) portable electronic units (40) intended to be fitted to said persons or objects and including reception means for said first and second electromagnetic signals, and (iii) means for detecting the direction of passage, through said entry-exit, of a person or an object fitted with a portable electronic unit. Each portable electronic unit includes amplitude measuring means for determining the reception amplitude of said first and second electromagnetic signals and comparator means for comparing the reception amplitude of the first and second electromagnetic signals so as to determine which of these two signals has the highest amplitude.

Claims

1. System for detecting the passage of persons or objects through an entry-exit (4) to a delimited space (2), including:

a detection device associated with said delimited space (2) and including transmission means (8) for transmitting different first and second electromagnetic signals (a, b) in respectively first and second communication regions (A, B) spatially separated from each other and partially overlapping, these first and second regions (A, B) each covering an entry-exit zone (32) defined by said entry-exit (4);

portable electronic units (40) intended to be fitted to said persons or objects and including reception means (41, 42;

41, 42a, 42b) for said first and second electromagnetic signals (a, b) transmitted by said transmission means (8); and

means for detecting the direction of passage, through said entry-exit (4, 5), of a person or an object fitted with one of said portable electronic units (40) as a function of the reception of said first and second electromagnetic signals,

characterised in that each portable electronic unit includes;

amplitude measuring means for determining the reception amplitude (RSSI;

RSSI_a, RSSI_b), by said portable electronic unit, of said first and second electromagnetic signals (a, b); and

comparator means (47) for comparing the reception amplitude of said first electromagnetic signal (a) with the reception amplitude of said second electromagnetic signal (b) so as to determine which of these two signals has the highest amplitude.

2. System according to claim 1, characterised in that said first and second electromagnetic signals (a, b) are transmitted at the same frequency and are multiplexed over time, said amplitude measuring means further including means (45, 46) for holding the reception amplitude measurement of the first electromagnetic signal (a), respectively of the second electromagnetic signal (b), during the amplitude measurement of the second electromagnetic signal (b), respectively of the first electromagnetic signal (a).

3. System according to claim 1, characterised in that said first and second electromagnetic signals (a, b) are simultaneously transmitted at different frequencies, each portable electronic unit (40) including first reception means (42a) tuned to the transmission frequency of said first electromagnetic signal (a) and second reception means (42b) tuned to the transmission frequency of said second electromagnetic signal (b).

4. System according to any of claims 1 to 3, characterised in that said comparator means (47) include a hysteresis comparator.

5. Portable electronic unit, particularly in the form of a card, to be fitted to a person or object and to allow detection of the passage of said person or object through an entry-exit (4) to a delimited space (2), said portable electronic unit including means (41, 42;

41, 42a, 42b) for receiving first and second electromagnetic signals (a, b) transmitted respectively in first and second communication regions (A, B) spatially separated from each other and partially overlapping, these first and second regions (A, B) each covering an entry-exit zone (32) defined by said entry-exit (4);

characterised in that each portable electronic unit further includes;

amplitude measuring means for determining the reception amplitude (RSSI;

RSSI_a, RSSI_b), by said portable electronic unit, of said first and second electromagnetic signals (a, b); and

comparator means (47) for comparing the reception amplitude of said first electromagnetic signal (a) with the reception amplitude of said second electromagnetic signal (b) so as to determine which of these two signals has the highest amplitude.

6. Electronic unit according to claim 5, characterised in that said first and second electromagnetic signals (a, b) are transmitted at the same frequency and are multiplexed over time, said amplitude measuring means further including means (45, 46) for holding the reception amplitude measurement of the first electromagnetic signal (a), respectively of the second electromagnetic signal (b), during the amplitude measurement of the second electromagnetic signal (b), respectively of the first electromagnetic signal (a).

7. Electronic unit according to claim 5, characterised in that said first and second electromagnetic signals (a, b) are simultaneously transmitted at different frequencies, each portable electronic unit (40) including first reception means (42a) tuned to the transmission frequency of said first electromagnetic signal (a) and second reception means (42b) tuned to the transmission frequency of said second electromagnetic signal (b).

8. Electronic unit according to any of claims 5 to 7, characterised in that said comparator means (47) include a hysteresis comparator.