Presence detection system and method

• US 8,542,118 B2
• Filed: 05/26/2011
• Issued: 09/24/2013
• Est. Priority Date: 05/27/2010
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Al-Kadi, Ghiath, Syed, Aly Aamer, Brandsma, Ewout
• Primary Examiner(s): Lu, Shirley
• Application Number:
  US13/116,824
• Publication Number:
  US 20110291832A1
• Time in Patent Office: 852 Days
• Field of Search: 340/541, 340/552, 340/556, 377/6
• US Class Current: 340/541
• CPC Class Codes: G01V 8/20 using multiple transmitters or receivers
• CPC Class Codes: G08B 13/183 by interruption of a radiation beam or barrier
• CPC Class Codes: H05B 47/115 by determining the presence or movement of objects or living beings
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

A presence detection system for detecting objects which move through an entrance of a space. The system is based on the idea to create a signature of a moving object which can be used to determine whether the object is a human being.

Claims

1. A presence detection system for detecting objects which move through an entrance of a space, comprising:

a light source for emitting invisible light;

a plurality of sensors for receiving the invisible light emitted by the light source; and

a sensor processing unit for creating a signature of a moving object;

the presence detection system being arranged such that, in use, a subset of the sensors receives the invisible light upon movement of the object through the entrance, and such that the sensor processing unit creates the signature based upon the composition of the subset, wherein the plurality of sensors comprises a two-dimensional array of sensors mounted substantially vertically in a frame of the entrance;

wherein the two-dimensional array of sensors comprises at least a first column of sensors and a second column of sensors;

and wherein the sensor processing unit is arranged to determine whether the object enters or leaves the space by monitoring the chronologic order in which the sensors of the first column and the sensors of the second column receive the invisible light,

characterized in that the plurality of sensors further comprises a one-dimensional array of sensors mounted in the frame substantially perpendicular to the two-dimensional array of sensors;

wherein the sensor processing unit is arranged to determine the height of the object by;

determining a distance value indicative of the distance between the object and the frame based upon signals generated by the sensors of the one-dimensional array, and

calculating the height of the object using the distance value and signals generated by the sensors of the two-dimensional array.

2. A presence detection system as claimed in claim 1, wherein the sensor processing unit comprises:

a memory unit for storing data provided by the plurality of sensors,

a hardware accelerator unit for computing the signature of the object,

a communication unit for communicating with controllable devices in the space, and

a central processing unit for controlling the memory unit, the hardware accelerator unit and the communication unit.

3. A presence detection system as claimed in claim 1, wherein the invisible light comprises infrared light.

4. A Heating Ventilation Air Conditioning system comprising a presence detection system as claimed in claim 1.

5. A lighting system comprising a presence detection system as claimed in claim 1.

6. An alarming system comprising a presence detection system as claimed in claim 1.

7. An entertainment system comprising a presence detection system as claimed in claim 1.

8. A presence detection method for detecting objects which move through an entrance of a space, wherein:

a light source emits invisible light;

a plurality of sensors receives the invisible light emitted by the light source;

a subset of the sensors receives the invisible light upon movement of an object through the entrance;

a sensor processing unit creates a signature of the object based upon the composition of the subset,

wherein the plurality of sensors comprise a two-dimensional array of sensors mounted substantially vertically in a frame of the entrance;

wherein the two dimensional array of sensor comprises at least a first column of sensors and a second column of sensor;

and wherein the sensor processing unit determines whether the object enters or leaves the space by monitoring the chronologic order in which the sensors of the first column and the sensors of the second column receive the invisible light,

characterized in that the plurality of sensors further comprises a one-dimensional array of sensors mounted in the frame substantially perpendicular to the two dimensional array of sensors;

wherein the sensor processing unit determines the height of the object by;

determining a distance value indicative of the distance between the object and the frame based upon signals generated by the sensors of the one dimensional array, and

calculating the height of the object using the distance value and signals generated by the sensors of the two dimensional array.