ANTENNA FOR NEAR FIELD COMMUNICATION, DRIVING APPARATUS AND LIGHT EMITTING DIODE LUMINAIRE

TECHNICAL FIELD

The present disclosure relates to an antenna for Near Field Communication (NFC), a driving apparatus including the antenna, and a light emitting diode (LED) luminaire including the driving apparatus.

BACKGROUND

NFC technology is widely used in various application fields, such as access control, transportation, payment or the like. Am NFC antenna is a core component of an NFC device, which largely determines the communication performance of the NFC device.

Therefore, designing a high-performance NFC antenna is pursuit of the person of skill in the art.

SUMMARY

The present disclosure designs a high-performance NFC antenna with high coupling performance in multiple directions and positions. The high-performance NFC antenna according to the present disclosure is particularly suitable for a driving apparatus of a LED luminaire, which makes it more convenient for the driving apparatus of the LED luminaire to communicate with external devices such as mobile phones in the near field, for example, to realize in-field programming of the driving apparatus.

According to one aspect of the present disclosure, there is provided an antenna for NFC, comprising a pillar support and a winding wire, wherein the winding wire is wound on the side surface of the pillar support to form a plurality of coils; the plurality of coils are electrically connected in series or in parallel; and adjacent coils among the plurality of coils are spaced apart from each other by a predetermined distance.

In some implementations, the pillar support is a cylinder or a prism.

In some implementations, the pillar support is a plastic hollow column.

In some implementations, the number of the plurality of coils is two or three.

According to another aspect of the present disclosure, there is provided a driving apparatus for a LED luminaire, comprising: a printed circuit board; a driver chip, mounted on the printed circuit board for driving LED(s) of the LED luminaire; and an antenna according to an embodiment of the present disclosure, wherein the antenna is electrically connected to the driver chip, which is for the driver chip to communicate information with an external device through NFC, and the antenna is mounted on the printed circuit board through its pillar support.

In some implementations, the driver chip is an in-field programmable driver chip, which receives programming codes from the external device through the antenna.

In some implementations, the pillar support of the antenna is vertically mounted on the printed circuit board.

According to another aspect of the present disclosure, there is provided a LED luminaire comprising a LED module comprising one or more LEDs; and a driving apparatus according to an embodiment of the present disclosure for driving the LED module.

BRIEF DESCRIPTION OF THE DRAWINGS

To explain the technical solutions of the embodiments of the present disclosure more clearly, a brief introduction to the appended drawings required in the description of the embodiments is given below. Obviously, the drawings in the following description are some example embodiments of the present disclosure only. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

FIG. 1 A and FIG. IB show schematic diagrams of the coupling performance of an NFC antenna based on a printed circuit board;

FIG. 2 shows a schematic structural diagram of an NFC antenna according to an embodiment of the present disclosure;

FIG. 3A-3D show schematic diagrams of the coupling performance of an NFC antenna according to an embodiment of the present disclosure;

FIG. 4 shows a schematic diagram of the coupling performance of an NFC antenna with one coil;

FIG. 5 shows a schematic structural diagram of an NFC antenna according to another embodiment of the present disclosure;

FIG. 6 shows a schematic structural diagram of an NFC antenna according to another embodiment of the present disclosure; and

FIG. 7 shows a schematic structural diagram of a LED luminaire and its driving apparatus, according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

In order to make the purposes, technical solutions, and advantages of the present disclosure more obvious, example embodiments according to the present disclosure will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of and not all of the embodiments of the present disclosure, and it should be understood that the present disclosure is not limited by the example embodiments described herein.

In this specification and the drawings, substantially the same or similar steps and elements are denoted by the same or similar reference symbols, and repeated descriptions of these steps and elements will be omitted. Meanwhile, in the description of the present disclosure, the terms "first", "second" or the like are only used to distinguish the description, and shall not be understood as indicating or implying relative importance or order.

As described in background, NFC is widely used in various fields, and designing a high-performance NFC antenna is pursuit of the person of skill in the art. The inventors of the present disclosure have discovered in research that for some applications, a NFC device needs to be able to interact with the counterpart NFC device of NFC from different directions and/or positions. However, it is difficult for normal NFC antennas to have high coupling performance, i.e. coupling efficiency, in multiple directions or positions.

For example, in the field of LED luminaire, a LED luminaire has a driving apparatus such as a Programmable Switch Unit (PSU) for powering and controlling LED modules with one or more LEDs. It is desirable for the driving apparatus to be able to be set with driving parameters, be programmed in the field, or collect other data through an external portable device such as a mobile phone. However, in many circumstances, such as in outdoor streetlight applications, a LED luminaire is usually not connected with a wired or wireless network. In order to write data to or program the driving apparatus, an NFC antenna can be set in the driving apparatus to use NFC for data transmission. NFC can easily send data to the driving apparatus by a portable device near the driver.

However, an NFC antenna of a driving apparatus usually needs to be set in the housing of the driving apparatus. The housing of the driving apparatus often includes metal parts, which have an impact on NFC. Therefore, it is needed to design an NFC antenna that can have high coupling efficiency in different directions and/or positions, so that communication can be carried out from other positions or directions when certain parts of the driving apparatus are shielded by the metal housing. Furthermore, due to the diversity of installation methods and positions of the LED luminaires, the directions and positions in which the portable device can easily access the NFC antenna are also different under different installation methods or positions. Therefore, it is desirable to design an NFC antenna that can have high coupling efficiency in multiple directions and/or locations.

Conventional NFC antennas generally have high coupling efficiency in only one direction or position, but low coupling efficiency in other positions and directions. For example, a planar antenna formed by printed wires on a Printed Circuit Board (PCB) only has a high coupling efficiency for magnetic lines of force in a direction perpendicular to the PCB, but low coupling efficiency for magnetic lines of force in a direction parallel to the PCB. FIG. 1A and FIG. IB respectively show schematic diagrams of the coupling performance of the planar antenna on the PCB in the perpendicular direction and the parallel direction. In FIG. 1 A and FIG. IB, antenna 101 is a planar antenna formed by printed wires on PCB 100, and antenna 102 which can be the same PCB antenna as antenna 101 or other similar antennas, such as other planar antennas generally used in portable devices, is the counterpart antenna for NFC with antenna 101. In FIG. 1A, antenna 101 and antenna 102 are placed in parallel. In this instance, the central magnetic lines of force emitted by antenna 102 is perpendicular to antenna 101, so that they can pass through antenna 101 well, as shown by the dashed line M in FIG. 1A. Similarly, the magnetic lines of force emitted by antenna 101 can also pass through antenna 102 well, such that the coupling efficiency between them is relatively high. On the contrary, in FIG. IB, antenna 101 and antenna 102 are placed perpendicularly, and antenna 101 is substantially aligned with the center of antenna 102. In this instance, the central magnetic lines of force emitted by antenna 102 is parallel to antenna 101 and can hardly pass through antenna 101, as shown by dashed line M in FIG. IB. Meanwhile, the edge magnetic lines of force emitted by antenna 102 is bent outwardly and can hardly pass through antenna 101 either, so that low coupling efficiency exists between them and cannot meet the communication requirements.

In view of the above problems, embodiments of the present disclosure provide an NFC antenna (i.e., an antenna for NFC) capable of achieving high coupling efficiency in different directions and positions.

FIG. 2 shows a schematic structural diagram of a NFC antenna 200 according to an embodiment of the present disclosure. NFC antenna 200 includes a pillar support 201 and a winding wire 202. Winding wire 202 is wound on the side surface of pillar support 201 to form a plurality of coils 202a and 202b. The winding wire can be any wire suitable for making a coil, such as a copper core enameled wire. Each coil may have multiple turns of winding. The example embodiment of FIG. 2 shows two coils 202a and 202b, but embodiments of the present disclosure may also use more coils, such as 3, 4, etc. Multiple coils are electrically connected in series or in parallel, and the choice of which can be determined according to specific applications. In the case of multiple coils electrically connected in series, the electrical potentials induced by the multiple coils can be accumulated. Those skilled in the art can design the winding direction and/or connection relationship of multiple coils according to practical application requirements, so as to achieve accumulation of potentials or currents required by practical applications. For example, the winding directions of two adjacent coils can be designed to be opposite in order to accumulate electrical potentials in some scenarios. In addition, adjacent coils among the plurality of coils are spaced apart from each other by a predetermined distance. In the example of FIG. 2, there are only two coils 202a and 202b, which are adjacent coils, and the separation distance between the two is d. The predetermined distance can be predetermined according to the specific application of antenna 200, for example, according to the shape and size of the counterpartcounterpart antenna to be used. In the case of having 3 or more coils, there are multiple groups of adjacent coils, and the predetermined distances between adjacent coils of different groups can be the same or different.

NFC antenna 200 shown in FIG. 2 is a three dimensional (3D) coil antenna (hereinafter also referred to as a "3D antenna"), and its pillar support 201 can be a column of any shape, for example, a cylinder or a prism, and the prism may be a prism with any cross-sectional shape, such as a prism with a square cross-section. Furthermore, pillar support 201 may adopt a hollow structure and/or lightweight materials to reduce the weight of NFC antenna 200. For example, pillar support 201 may be a plastic hollow column. The multi-coil 3D structure of NFC antenna 200 makes coupling forms of the magnetic field more abundant, such that the antenna can have higher coupling efficiency in different directions and positions.

The coupling performance of the NFC antenna in different directions and positions according to an embodiment of the present disclosure will be described below with reference to FIGs. 3A-3D. FIGs. 3A-3D take 3D antenna 200 with two coils in FIG. 2 as an example for description. As an example, FIGs. 3A-3D use 3D antenna 200 as the receiver antenna, and planar antenna 102 shown in FIG. 1 as the transmitting antenna to illustrate the coupling performance between them. It is understood by those skilled in the art that the coupling performance of using 3D antenna 200 as the transmitting antenna and planar antenna 102 as the receiver antenna is similar. The reason why planar antenna 102 is selected as the counterpart antenna of 3D antenna 200 in an embodiment of the present disclosure is that the NFC antenna in a portable device is usually a planar antenna.

In FIG. 3 A, planar antenna 102 is located on the top of 3D antenna 200, and planar antenna 102 is perpendicular to the pillar support of 3D antenna 200 (that is, perpendicular to the axis of the pillar support). In this instance, the central magnetic lines of force emitted by planar antenna 102 are substantially perpendicular to the coil of 3D antenna 200 (that is, parallel to the axis of the pillar support), and thus can pass through the coil of 3D antenna 200 to achieve high coupling efficiency.

In FIG. 3B, planar antenna 102 is located at the side of 3D antenna 200 and parallel to the pillar support of 3D antenna 200. In addition, the center of planar antenna 102 is substantially aligned to the middle of two coils 202a and 202b of 3D antenna 200. In this instance, both coil 202a and coil 202b are not aligned to the center of planar antenna 102. Therefore, the magnetic lines of force directed to coil 202a and coil 202b emitted by planar antenna 102 are not parallel to the respective coils, such that good coupling can be achieved. As shown in FIG. 3B, magnetic lines of force Ml directed to coil 202a are not parallel to coil 202a, so they can pass through coil 202a; magnetic lines of force M2 aligned to coil 202b are not parallel to coil 202b, so they can pass through coil 202b. Therefore, high coupling efficiency is formed between 3D antenna 200 and planar antenna 102.

In FIG. 3C, planar antenna 102 is also located at the side of 3D antenna 200 and parallel to the pillar support of 3D antenna 200, but the center of planar antenna 102 is substantially aligned to the middle of coil 202a of 3D antenna 200. In this instance, the central magnetic lines of force Ml directed to coil 202a emitted by planar antenna 102 are substantially parallel to coil 202a (that is, perpendicular to the pillar support), so that central magnetic lines of force Ml cannot effectively pass through coil 202a to couple with it. However, coil 202b is not aligned to the center of planar antenna 102. Therefore, magnetic lines of force M2 aligned to coil 202b emitted by planar antenna 102 are not parallel to coil 202b and can pass through coil 202b to achieve good coupling. Therefore, 3D antenna 200 can still achieve a high coupling efficiency with planar antenna 102.

In FIG. 3D, planar antenna 102 is also located at the side of 3D antenna 200 and parallel to the pillar support of 3D antenna 200, but the center of planar antenna 102 is substantially aligned to the middle of coil 202b of 3D antenna 200. In this instance, central magnetic lines of force M2 directed to coil 202b emitted by planar antenna 102 are substantially parallel to coil 202b (that is, perpendicular to the pillar support), so that they cannot effectively pass through coil 202b to couple with it. However, coil 202a is not aligned to the center of planar antenna 102. Therefore, magnetic lines of force Ml directed to coil 202a emitted by planar antenna 102 is not parallel to coil 202a and can pass through coil 202a to achieve better coupling. Therefore, 3D antenna 200 can still achieve high coupling efficiency with planar antenna 102.

According to the above description of FIGs. 3A-3D, the NFC antenna according to an embodiment of the present disclosure can achieve high coupling efficiency in different directions and positions, which has obvious advantages relative to the planar antenna shown in FIG. 1. The planar antenna shown in Fig. 1 has good coupling efficiency only when the counterpart antenna is parallel to it. Moreover, the NFC antenna according to an embodiment of the present disclosure has a plurality of mutually distanced coils, such that the counterpart antenna has good coupling efficiency at multiple positions at its side. This is because multiple distanced coils can avoid that the magnetic lines of force directed to all coils emitted by the antenna of the counterpart are perpendicular to the receiving direction for the magnetic field of the coils, resulting in a situation that the NFC antenna cannot effectively receive the magnetic field sent by the counterpart antenna. In contrast, if the 3D antenna has only one coil, when planar antenna 102 is located at its side and the center of planar antenna 102 is substantially aligned to the middle of the one coil, the central magnetic lines of force emitted by planar antenna 102 are parallel to the one coil (that is, perpendicular to the receiving direction of the coil), so that the 3D antenna has poor coupling performance in this instance.

FIG. 4 shows a schematic diagram of the coupling performance of stereo antenna 400 with only one coil and counterpart planar antenna 102. The difference between 3D antenna 400 in FIG. 4 and 3D antenna 200 in FIG. 2 is that 3D antenna 400 has only one coil 402, while 3D antenna 200 in FIG. 2 has two mutually distanced coils 202a and 202b. Similar to FIGs. 3A-3D, FIG. 4 uses 3D antenna 400 as a receiver antenna and planar antenna 102 as a transmitting antenna. In FIG. 4, planar antenna 102 is located at the side of 3D antenna 400 and parallel to the pillar support of 3D antenna 400, and the center of planar antenna 102 is substantially aligned to the middle of coil 402 of 3D antenna 400. In this instance, the central magnetic lines of force emitted by antenna 102 are substantially parallel to coil 402, which makes it difficult for the central magnetic lines of force to pass through coil 402 to achieve good coupling. Comparing to FIGs. 3B-3D, the 3D antenna with a plurality of mutually distanced coils according to an embodiment of the present disclosure does not have the situation that the center of counterpart planar antenna 102 is aligned to all the coils. Therefore, compared with the 3D antenna with only one coil, the 3D antenna with multiple coils can make the counterpart coil have higher coupling efficiency in more positions.

It should be noted that, as described above, the NFC antenna according to an embodiment of the present disclosure is not limited to only having two coils, but may have 3 or more coils. More coils can lead to more locations with higher coupling efficiency, and make the antenna more convenient to use. FIG. 5 shows an NFC antenna 500 with three mutually distanced coils 502a, 502b, and 502c. Among the three coils, there are two sets of adjacent coils, namely coils 502a and 502b, coils 502b and 502b. The distance dl between coils 502a and 502b and the distance d2 between coils 502b and 502b can be the same or different. In addition, the pillar support of the NFC antenna according to an embodiment of the present disclosure is not limited to a cylinder, but can also be a prism with any cross- sectional shape. FIG. 6 shows an NFC antenna 600 with a prism with a square cross-section as the pillar support, which has two coils 602a and 602b. The distance between coils 602a and 602b is d.

The NFC antenna according to an embodiment of the present disclosure can be used in various devices with NFC function to facilitate a user's portable device (such as a mobile phone) to access the device from different directions and positions to achieve good NFC interaction. In particular, an embodiment of the present disclosure provides a driving apparatus of LED luminaire using the NFC antenna.

FIG. 7 shows a driving apparatus 701 and an LED luminaire 700 having driving apparatus 701 according to an embodiment of the present disclosure. As shown in the figure, LED luminaire 700 comprises a driving apparatus 701 and an LED module 702. Driving apparatus 701 is used to drive LED module 702, for example, to supply power to LED module 702, and/or to control the switch, brightness, color or the like of LED module 702. LED module 702 can comprise one or more LEDs. Driving apparatus 701 comprises a PCB 7011 on which a driver chip 7012 and an antenna 7013 according to an embodiment of the present disclosure are mounted. Driver chip 7012 is used to drive the LEDs in LED luminaire 700. Antenna 7013 is electrically connected to driver chip 7012 for driver chip 7012 to communicate information with an external device (for example, a portable device) through NFC. The interaction between driving chip 7012 and an external device includes, for example, obtaining driving parameters or other data from the external device, or receiving programming codes from the external device through antenna 7013 to achieve in-field programming when driving chip 7012 is an in-field programmable driver chip. In addition, if necessary, driver chip 7012 can also send data to the portable device through NFC, for example, send status data of the LED luminaire to the portable device. Antenna 7012 is mounted on the PCB 7011 through its pillar support, for example, it can be perpendicularly mounted on PCB 7011 as shown in FIG. 7. It should be noted that, according to an embodiment of the present disclosure, driving apparatus 701 and LED module 702 may be integrated together in a housing, or used as separate components in their respective housings. In addition, driving apparatus 701 and LED luminaire 700 according to an embodiment of the present disclosure may also comprise other components not shown in the figure.

Driving apparatus 701 according to an embodiment of the present disclosure can be conveniently programmed on the production line and in the field. When driving apparatus 701 is on the production line, PCB 7011 of driving apparatus 701 is usually parallel to a conveyor belt, and an external device for programming is usually set at the side of the conveyor belt. In this instance, the antenna of the external device can be coupled at the side of antenna 7012 of the driving apparatus. When driving apparatus 701 is used in the field, although the direction and position of driving apparatus 701 convenient for users may be changed due to the diversity of its installation positions and methods, the NFC antenna of driving apparatus 701 according to the present disclosure can have high coupling performance in multiple directions and positions. Therefore, users can use portable devices to couple with the antenna in multiple different directions and positions, which greatly improves the convenience of in-field programming or data transmission.

Those skilled in the art should understand that the specific embodiments mentioned above are only examples and not limitations. Various modifications, combinations, partial combinations and substitutions can be made to the embodiments of the present disclosure according to design requirements and other factors, as long as they fall within the scope of the appended claims or their equivalents.

The block diagrams of circuits, units, components, apparatus, devices and systems involved in the present disclosure are merely illustrative examples and not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these circuits, units, components, apparatus, devices and systems can be connected, arranged, and configured in any manner, as long as the desired purpose can be achieved. The circuits, units, components, apparatus involved in the present disclosure may be implemented in any suitable manner, such as an Application- Specific Integrated Circuit(ASIC), a Field Programmable Gate Array (FPGA), etc., or a general purpose processor combined with programs.