Device for detecting an approach
A device for detecting an approach of a part of a user's body or of a portable user equipment, intended to be housed on board a motor vehicle, including: a near-field communication antenna configured to transmit signals at a high frequency selected between 3 and 30 MHz, the antenna being able to detect the approach of a portable user equipment and to communicate in near-field mode with the portable user equipment. The antenna including at least one winding that extends continuously in the form of a set of comb-shaped rods such that the antenna is able to generate a variation in capacitance in response to the approach of a part of a user's body; a controller for controlling the antenna; and a measurer for measuring a variation in impedance of the antenna, generated by the variation in capacitance.
1 . A device for detecting an approach of a part of a user's body or of a portable user equipment, intended to be housed on board a motor vehicle, the device comprising:
a) a control means; and
b) a near-field communication antenna configured to transmit signals at a high frequency selected between 3 and 30 MHZ, said antenna being able to detect the approach of the portable user equipment and to communicate in near-field mode with said portable user equipment, said antenna consisting of:
i) a first section having at least one winding connected to the control means for controlling said antenna, and
ii) a second section electrically connected to, and extending continuously from the first section, the second section being in the form of a set of comb-shaped rods such that said antenna is able to generate a variation in capacitance in response to the approach of a part of the user's body, and
wherein, the control means comprises measuring means for measuring a variation in impedance of said antenna, the impedance being modified by the variation in capacitance of the antenna in response to the approach of a part of the user's body, or upon the approach of the portable user equipment.
2 . The detection device as claimed in claim 1 , wherein the at least one winding defines a perimeter within which said antenna extends continuously in the form of a set of comb-shaped rods.
3 . The detection device as claimed in claim 2 , wherein, with the perimeter being rectangular, the rods are in the form of copper tracks perpendicular to a length or width of the perimeter.
4 . The detection device as claimed in claim 2 , wherein said antenna comprises rods on two opposing sides of the perimeter.
5 . The detection device as claimed in claim 1 , wherein the rods are identical to one another.
6 . The detection device as claimed in claim 1 , wherein the measuring means for measuring a variation in impedance are in the form of software and measure any variation in phase, in current or in voltage coming from the antenna.
7 . A vehicle door handle, comprising a detection device as claimed in claim 1 .
8 . An inductive charger for a portable user equipment, comprising a detection device as claimed in claim 1 .
9 . A motor vehicle, comprising a detection device as claimed in claim 1 .
10 . A device for detecting an approach of a part of a user's body or of a portable user equipment, intended to be housed on board a motor vehicle, the device comprising:
a) a control means; and
b) a near-field communication antenna configured to transmit signals at a high frequency selected between 3 and 30 MHZ, said antenna being able to detect the approach of the portable user equipment and to communicate in near-field mode with said portable user equipment, said antenna comprising:
i) a first section having one continuous winding electrically connected to the control means at a first connection point and a second connection point, the control means for controlling said antenna, and
ii) a second section electrically connected to the control means at the first connection point and the second connection point, the second section being in the form of a set of comb-shaped rods such that said antenna is able to generate a variation in capacitance in response to the approach of a part of the user's body, and
wherein, the control means comprises measuring means for measuring a variation in impedance of said antenna, the impedance being modified by the variation in capacitance of the antenna in response to the approach of a part of the user's body, or upon the approach of the portable user equipment.