METHOD, DEVICE, COMPUTER PROGRAM AND COMPUTER PROGRAM PRODUCT FOR DETERMINING WHETHER A PORTABLE KEY DEVICE IS LOCATED IN AN ACTIVE AREA IN RELATION TO A BARRIER

• US 20180052217A1
• Filed: 03/24/2016
• Published: 02/22/2018
• Est. Priority Date: 03/27/2015
• Status: Active Grant

• Current Assignee: Assa Abloy AB
• Original Assignee: Assa Abloy AB
• Inventors: JONSSON, Tomas
• Granted Patent: US 10,228,444 B2
• Time in Patent Office: Days
• CPC Class Codes: G01S 19/51 Relative positioning
• CPC Class Codes: G01S 2205/01 specially adapted for specific applications
• CPC Class Codes: G01S 3/46 using antennas spaced apart and measuring phase or time difference between signals therefrom, i.e. path-difference systems
• CPC Class Codes: G01S 3/48 the waves arriving at the antennas being continuous or intermittent and the phase difference of signals derived therefrom being measured
• CPC Class Codes: G01S 3/50 the waves arriving at the antennas being pulse modulated and the time difference of their arrival being measured
• CPC Class Codes: G01S 5/00 Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using active systems G01S13/00, G01S15/00, G01S17/00
• CPC Class Codes: G01S 5/04 Position of source determined by a plurality of spaced direction-finders
• CPC Class Codes: G01S 5/06 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/12 takes precedence
• CPC Class Codes: G01S 5/12 by co-ordinating position lines of different shape, e.g. hyperbolic, circular, elliptical or radial
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: G07C 2209/63 Comprising locating means for detecting the position of the data carrier, i.e. within the vehicle or within a certain distance from the vehicle
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 40/06 based on characteristics of available antennas

Abstract

It is presented a method for determining whether a portable key device is located in an active area in relation to a barrier. The method is performed in an access control device and comprising the steps of: detecting a first angle of arrival of a wireless signal from the portable key device using a first pair of separated antennas; detecting a second angle of arrival of a wireless signal from the portable key device using a second pair of separated antennas; determining a first pair of directions based on the first angle of arrival; determining a second pair of directions based on the second angle of arrival; determining a position of the portable key device to be where one of the first pair of directions intersects one of the second pair of directions; and determining whether the portable key device is located in the active area based on the position.

Claims

1. A method for determining whether a portable key device is located in an active area in relation to a barrier, wherein the active area is on the outside of the barrier, the method being performed in an access control device and comprising the steps of:

detecting a first angle of arrival of a wireless signal from the portable key device using a first pair of separated antennas;

detecting a second angle of arrival of a wireless signal from the portable key device using a second pair of separated antennas, wherein the first pair of antennas is located on the outside of the barrier and the second pair of antennas is located on the inside of the barrier;

determining a first pair of directions based on the first angle of arrival;

determining a second pair of directions based on the second angle of arrival;

determining a position of the portable key device to be where one of the first pair of directions intersects one of the second pair of directions, wherein any intersection located between a first line (6a) between the first pair of antennas and a second line between the second pair of antennas is discarded for determining the position; and

determining whether the portable key device is located in the active area based on the position.

2. The method according to claim 1, wherein the step of detecting a first angle of arrival comprises detecting the first angle of arrival based on a time difference of receiving the wireless signal in the first pair of separated antennas and wherein the step of detecting a second angle of arrival comprises detecting the second angle of arrival based on a time difference of receiving the wireless signal in the second pair of separated antennas.

3. The method according to claim 1, wherein the first pair of separated antennas and the second pair of separated antennas contain one and only one common antenna.

4. The method according to claim 1, wherein the first pair of separated antennas and the second pair of separated antennas contain different antennas.

5. The method according to claim 1, wherein the step of determining a first pair of directions comprises determining each direction as a direction from a first midpoint between the first pair of antennas with the first angle of arrival being on either side, respectively, of a first line between the first pair of antennas, and the step of determining a second pair of directions comprises determining each direction as a direction from a second midpoint between the second pair of antennas with the second angle of arrival being on either side, respectively, of a second line between the second pair of antennas.

6. The method according to claim 1, further comprising the step of:

determining a distance to the portable key device from one of the antennas; and

wherein the step of determining a position comprises determining a position based on the distance.

7. The method according to claim 6, wherein the step of determining a position comprises determining a position in three dimensions.

8. An access control device arranged to determine whether a portable key device is located in an active area in relation to a barrier, wherein the active area is on the outside of the barrier, the access control device comprising:

a processor; and

a memory storing instructions that, when executed by the processor, causes the access control device to;

detect a first angle of arrival of a wireless signal from the portable key device using a first pair of separated antennas;

detect a second angle of arrival of a wireless signal from the portable key device using a second pair of separated antennas, wherein the first pair of antennas is located on the outside of the barrier and the second pair of antennas is located on the inside of the barrier;

determine a first pair of directions based on the first angle of arrival determine a second pair of directions based on the second angle of arrival;

determine a position of the portable key device to be where one of the first pair of directions intersects one of the second pair of directions, wherein any intersection located between a first line between the first pair of antennas and a second line between the second pair of antennas is discarded for determining the position; and

determining whether the portable key device is located in the active area based on the position.

9. The access control device according to claim 8, wherein the instructions to detect a first angle of arrival comprise instructions that, when executed by the processor, causes the access control device to detect the first angle of arrival based on a time difference of receiving the wireless signal in the first pair of separated antennas and wherein the instructions to detect a second angle of arrival comprise instructions that, when executed by the processor, causes the access control device to detecting the second angle of arrival based on a time difference of receiving the wireless signal in the second pair of separated antennas.

10. The access control device according to claim 8, wherein the instructions to determine a first pair of directions comprise instructions that, when executed by the processor, causes the access control device to determine each direction as a direction from a first midpoint between the first pair of antennas with the first angle of arrival being on either side, respectively, of a first line between the first pair of antennas, and the instructions to determine a second pair of directions comprise instructions that, when executed by the processor, causes the access control device to determine each direction as a direction from a second midpoint between the second pair of antennas with the second angle of arrival being on either side, respectively, of a second line between the second pair of antennas.

11. The access control device according to claim 8, further comprising instructions that, when executed by the processor, causes the access control device to determine a distance to the portable key device from one of the antennas;

and wherein the instructions to determine a position comprise instructions that, when executed by the processor, causes the access control device to determine a position based on the distance.

12. A computer program for determining whether a portable key device is located in an active area in relation to a barrier, wherein the active area is on the outside of the barrier, the computer program comprising computer program code which, when run on an access control device, causes the access control device to:

detect a first angle of arrival of a wireless signal from the portable key device using a first pair of separated antennas;

detect a second angle of arrival of a wireless signal from the portable key device using a second pair of separated antennas, wherein the first pair of antennas is located on the outside of the barrier and the second pair of antennas is located on the inside of the barrier;

determine a first pair of directions based on the first angle of arrival;

determine a second pair of directions based on the second angle of arrival; and

determine a position of the portable key device to be where one of the first pair of directions intersects one of the second pair of directions, wherein any intersection located between a first line between the first pair of antennas and a second line between the second pair of antennas is discarded for determining the position; and

determine whether the portable key device is located in the active area based on the position.

13. A computer program product comprising a computer program according to claim 12 and a computer readable means on which the computer program is stored.