Slot antenna for LED light strip lighting device and applications thereof

Abstract

The present disclosure relates to a slot antenna for LED light strip lighting devices and applications thereof. One aspect of the present disclosure relates to a slot antenna for a light emitting diode (LED) light strip lighting device having an integrated communication module. The slot antenna and the LED light strip lighting device having the integrated communication module can be provided as part of a lighting fixture. In some embodiments, the lighting fixture includes a printed circuit board (PCB) including a plurality of LEDs mounted on the PCB, a radio communication module mounted on the PCB, and a coplanar coupling structure coupled to the radio communication module. In some embodiments, the PCB is configured to feed the slot antenna through the coplanar coupling structure. In some embodiments, the slot antenna is disposed parallel to and separate from the coplanar coupling structure.

Description

[0001] Cross-referencing related applications

[0002] This application claims the benefits of U.S. Provisional Application No. 63 / 686,379, filed August 23, 2024, and U.S. Provisional Application No. 63 / 739,742, filed December 30, 2024, both of which are hereby expressly incorporated herein by reference in their entirety. Technical Field

[0003] The technology disclosed herein generally relates to slot antennas for light-emitting diode (LED) strip lighting devices, and more specifically to slot antennas for LED strip lighting devices with integrated communication modules. Background Technology

[0004] LED lighting devices offer numerous advantages over traditional lighting systems (e.g., incandescent lighting devices), including reduced energy consumption, increased lifespan and durability, and lower costs. As an example, LED strip lighting devices, which include printed circuit boards (PCBs) with arrays of surface-mount LEDs (SMD LEDs) mounted on them, have become common in various applications, such as home and industrial applications. Specifically, lighting fixtures incorporating such LED strip lighting devices can further include various electronic components, such as drivers, antennas, and radio communication devices, to provide wireless control of the LED strip lighting device. Typically, small-area and low-height antennas are desirable to prevent unwanted shadows on the lighting fixture. However, when the lighting fixture includes a large-area metal backplate armature (or reflector), the armature may interfere with low-height antenna solutions. Furthermore, to improve antenna efficiency, the antenna should be pointed away from the armature and away from any PCB mounted on the armature; however, such solutions may produce undesirable shadows in the light pattern. Therefore, existing LED strip lighting device implementations have not yet proven to be completely satisfactory in all aspects. Summary of the Invention

[0005] Embodiments of this disclosure include systems, apparatus, and methods for providing slot antennas for LED strip lighting devices with integrated communication modules.

[0006] In an exemplary aspect, the lighting device includes a printed circuit board (PCB) comprising a plurality of light-emitting diodes (LEDs) mounted on the PCB, a radio communication module mounted on the PCB, and a coplanar coupling structure coupled to the radio communication module. In some embodiments, the PCB is configured to feed a slot antenna through the coplanar coupling structure. In some embodiments, the slot antenna is positioned parallel to and separate from the coplanar coupling structure.

[0007] In some embodiments, the lighting device further includes a metal armature that includes an opening defining a slot, wherein the slot provides a slot antenna. In some embodiments, a PCB is mechanically attached to the metal armature.

[0008] In some embodiments, the slot includes a half-wavelength slot.

[0009] In some embodiments, the metal armature is configured to provide a radiator for the slot antenna.

[0010] In some embodiments, the groove includes a Z-shaped groove or a V-shaped groove.

[0011] In some embodiments, the PCB comprises a single-layer rigid PCB.

[0012] In some embodiments, the mechanically attached PCB covers approximately half of the groove.

[0013] In some embodiments, the PCB is configured to feed the slot antenna capacitively or inductively via a coplanar coupling structure.

[0014] In some embodiments, the lighting device further includes an LED driver mounted on a PCB, wherein the LED driver is coupled to a radio communication module and to a plurality of LEDs to drive the plurality of LEDs.

[0015] In some embodiments, the lighting device further includes a matching network coupled to a coplanar coupling structure and to the output of a radio communication module.

[0016] In some embodiments, the coplanar coupling structure includes coupling traces, which include conductive traces on a PCB.

[0017] In another exemplary aspect, the lighting device includes an armature comprising a slot integral with the armature, wherein the slot provides a slot antenna. In some embodiments, the lighting device further includes a light-emitting diode (LED) strip printed circuit board (PCB) mechanically attached to the armature. In some embodiments, the lighting device further includes a radio chip mounted on the LED strip PCB and coupled to a coupling trace defined by conductive traces of the LED strip PCB. In some embodiments, the LED strip PCB is configured to capacitively or inductively feed the slot antenna via the coupling trace.

[0018] In some embodiments, the coupling trace defines a first conductive plane, and the armature defines a second conductive plane that is parallel to the first conductive plane and separated from the first conductive plane by a distance substantially equal to the thickness of the insulating substrate of the LED strip PCB.

[0019] In some embodiments, the groove includes a Z-shaped groove or a V-shaped groove.

[0020] In some embodiments, the LED light strip PCB includes a single-layer rigid PCB.

[0021] In some embodiments, the LED strip PCB covers approximately half of the groove.

[0022] In some embodiments, the radio chip includes a radio frequency (RF) terminal that provides an RF output of the radio chip, and wherein the RF output is coupled to a coupling trace.

[0023] In some embodiments, a matching network is coupled between the RF output and the coupling trace.

[0024] In another exemplary aspect, the lighting device includes an armature comprising a Z-slot providing a slot antenna. In some embodiments, the lighting device further includes a printed circuit board (PCB) attached to the armature and covering approximately half of the Z-slot. In some embodiments, the PCB includes an array of light-emitting diodes (LEDs), an LED driver coupled to the array of LEDs to drive the LEDs, and a radio chip coupled to the LED driver and to a matching network connected to the output of the radio chip. In some embodiments, the matching network is further coupled to conductive coupling traces on the PCB. In some embodiments, the PCB is configured to capacitively or inductively feed the Z-slot through the conductive coupling traces.

[0025] In some embodiments, the Z-groove has a first length equal to about half the wavelength of the target frequency, and the conductive coupling trace has a second length equal to about one-quarter the wavelength of the target frequency.

[0026] Further aspects, features, and advantages of this disclosure will become apparent from the following detailed description. Attached Figure Description

[0027] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several aspects of this disclosure and, together with the description of the drawings, serve to explain the principles of this disclosure.

[0028] Figure 1A A top perspective view of a lighting fixture according to some embodiments is shown.

[0029] Figure 1B A bottom perspective view of a lighting device according to some embodiments is shown.

[0030] Figure 1C Demonstrates some embodiments Figure 1B An enlarged view of a portion of the lighting equipment.

[0031] Figure 2A top view is shown of a portion of a printed circuit board (PCB) mounted on an armature including a slot, according to some embodiments.

[0032] Figure 3 A simplified top view is shown, illustrating an electrical / RF schematic of an assembly for coupling to a PCB according to some embodiments.

[0033] Figure 4 A top perspective view of a portion of a PCB mounted on an armature, according to some embodiments, is shown.

[0034] Figure 5 Another top perspective view shows a portion of a PCB mounted on an armature according to some embodiments.

[0035] Figure 6 , 7 Figures 8, 9, and 10 illustrate various exemplary simulation results of lighting fixtures including Z-grooves and attached PCBs according to some embodiments. Detailed Implementation

[0036] For the purpose of facilitating an understanding of the principles of this disclosure, embodiments illustrated in the accompanying drawings will now be described using specific language. Nevertheless, it should be understood that this is not intended to limit the scope of this disclosure. Any changes and further modifications to the described systems, apparatus, and methods, as well as any further application of the principles of this disclosure, are fully considered and included within this disclosure, as would normally occur to those skilled in the art to which this disclosure pertains. Specifically, upon careful consideration, features, components, and / or steps described with respect to one embodiment may be combined with features, components, and / or steps described with respect to other embodiments of this disclosure. However, for the sake of brevity, multiple repetitions of these combinations will not be described separately.

[0037] Compared to conventional lighting systems (e.g., incandescent lighting fixtures), light-emitting diode (LED) lighting fixtures are more energy-efficient and offer advantages such as longer lifespan, better durability, and lower costs. In one example, LED lighting fixtures can be implemented as LED strip lighting fixtures, which have become common in various applications, including residential and industrial applications (e.g., office lighting, restroom lighting, supermarket lighting, classroom lighting, corridor lighting, etc.). In various cases, LED strip lighting fixtures include a printed circuit board (PCB) on which an array of surface-mount LEDs (SMD LEDs) are mounted. In various examples, LED strip lighting fixtures can be manufactured on rigid or flexible substrates and can provide a variety of fixed and variable colors and brightness levels. Lighting installations incorporating LED strip lighting fixtures can also include various other electronic components that provide wireless control of the LED strip lighting fixtures, such as drivers, antennas, radio communication devices, etc. Typically, small-area and low-height antennas are desirable to prevent unwanted shading on the lighting fixture. However, when the lighting fixture includes a large-area metal backplate armature (or reflector), the armature may interfere with low-height antenna solutions. Furthermore, to improve antenna efficiency, the antenna should be pointed away from the armature and away from any PCB mounted on the armature; however, such solutions may produce undesirable shadows in the light pattern. Therefore, existing LED strip lighting implementations have not yet proven to be completely satisfactory in all aspects.

[0038] The embodiments of this disclosure offer advantages over the prior art, but it should be understood that other embodiments may offer different advantages, and not all advantages are necessarily discussed herein, nor are specific advantages required in all embodiments. For example, the embodiments discussed herein include systems, apparatus, and methods for providing slot antennas for LED strip lighting devices with integrated communication modules, which are effectively used to overcome various disadvantages of prior art implementations. In some embodiments, the lighting device includes a large-area metal backplate armature (or reflector) having a half-wavelength slot formed therein to provide a slot antenna integrated with the armature, wherein the armature acts as a radiator of the slot antenna. In various cases, the half-wavelength slot formed in the armature may include a V-shaped slot or a Z-shaped slot, as discussed in more detail below. By using a half-wavelength slot in the metal backplate (armature), embodiments of this disclosure provide efficient antennas that remain compatible with standard manufacturing practices.

[0039] In this example, the armature provides an infinitely large ground plane, on which the PCB (with an array of SMD LEDs mounted) is mechanically, rather than electrically, attached to the armature. For example, the PCB can be attached to the armature using screws, bolts, rivets, or other suitable fasteners. Alternatively, in some embodiments, the PCB can be attached to the armature using an adhesive backing provided along the back of the PCB. In some embodiments, the PCB comprises a single-layer rigid PCB including a linear array of SMD LEDs mounted thereon. For the purposes of the discussion provided herein, a PCB having an array of LEDs can be equivalently referred to as an "LED strip PCB" or "LED PCB". For example, according to embodiments of this disclosure, the single-layer PCB includes a conductive material (e.g., copper) only on one side of an insulating substrate (e.g., glass fiber, glass fiber-epoxy laminate, or other suitable material), wherein the conductive material is patterned to provide conductive traces for coupling to the array of LEDs and for other electronic components mounted thereon and / or electronic circuitry defined therein. Specifically, in various embodiments, in addition to the array of LEDs, a radio communication module (or radio chip) is also mounted on a single-layer PCB. For example, the radio chip includes a radio frequency (RF) output coupled to a matching network and / or filter network separate from the radio chip but also disposed on the LED strip PCB. The matching network and / or filter network is further connected to a coupling trace provided by conductive PCB traces. In various embodiments, the LED strip PCB is attached to the armature near a half-wavelength slot (slot antenna) in a metal backplane (armature) such that the feed of the half-wavelength slot is provided through a coplanar coupling structure (coupling trace) on the LED strip PCB, which is parallel to the surface of the armature (and therefore parallel to the half-wavelength slot) and covers at least a portion of the half-wavelength slot (e.g., half of the slot antenna in some cases). In various embodiments, the coplanar coupling structure may capacitively and / or inductively feed the half-wavelength slot (slot antenna). The disclosed LED strip PCB (including radio chip and coupling structure) and slot antenna (where the armature is used as the radiator of the slot antenna) thus provide efficient wireless control of an array of LEDs mounted on the LED strip PCB.

[0040] It should also be noted that since the armature may already include mounting holes for the LED strip PCB, the disclosed slot antenna can be provided without additional cost. Another advantage is that there is no problem with fragile wires protruding from the LED strip PCB, which could bend (and cause detuning) or cause shadows in the lighting pattern. Furthermore, the structure disclosed herein is easy to manufacture and reproducible. For example, alignment of the antenna slot and the LED strip PCB (including the radio chip and coupling structure) is not an issue. Further, the mounting tolerances of the LED strip PCB are much smaller than those required for high-efficiency antennas, and it is robust to manufacture. Generally, embodiments of this disclosure can therefore be used to manufacture inexpensive, mechanically robust, and scalable opto-armatures that can be easily implemented in a variety of consumer and industrial applications, including various Internet of Things (IoT) applications. Further details of embodiments of this disclosure are provided below, and further benefits and / or other advantages will become apparent to those skilled in the art who benefit from this disclosure.

[0041] Now for reference Figure 1A and Figure 1B , Figure 1A A top perspective view of a lighting fixture 100 according to some embodiments is shown, and Figure 1B A bottom perspective view of a lighting fixture 100 according to some embodiments is shown. In various instances, the lighting fixture 100 may be attached to an overhead structure (e.g., a ceiling), and in some cases, the lighting fixture 100 may be suspended by cables, chains, supports, or other suitable connectors. While specific embodiments of the lighting fixture 100 have been shown and described, it will be understood that embodiments of this disclosure can be used in a variety of other types and / or configurations of lighting fixtures without departing from the scope of this disclosure.

[0042] As shown, the lighting fixture 100 includes an armature 102 formed of a large-area conductive metal backplate. In some instances, the armature 102 may provide a reflector to reflect and guide light generated within the lighting fixture 100 (e.g., by an LED). As previously described, the armature 102 provides an infinitely large ground plane to which the LED strip PCB is mechanically attached, as described in more detail below. In some embodiments, the armature 102 may be formed of a metal plate, aluminum, or other conductive material. As shown, the armature 102 also has a substantially flat region 104, with sloping flat regions 106 extending from the substantially flat region on each side of the flat region 104. In some cases, instead of the sloping flat regions 106, the armature 102 may include convex or concave regions extending from each side of the flat region 104. More generally, in some embodiments, the armature 102 may have an overall parabolic or concave shape. It is certain that while some embodiments of the shape of the armature 102 have been provided, it will be understood that the exemplary shapes disclosed herein are not intended to be limiting.

[0043] In various embodiments, a half-wavelength slot 108 (or slot 108) is formed within the armature 102 and is an integral part of the armature 102, as the slot 108 is defined by an opening formed in a conductive metal backplate providing the armature 102. For example, the size of the slot 108 is set to resonate in a desired frequency band (or target frequency band), thereby forming a slot antenna suitable for wireless communication and control of LEDs mounted on an LED strip PCB. In various embodiments, the armature 102 also functions as a radiator for the slot antenna. As described in more detail below, the length of the slot 108 is approximately half the radiating wavelength in the desired frequency band (or target frequency band). In some embodiments, the desired frequency band (or target frequency band) can be approximately 2.4-2.5 GHz. Therefore, and in some instances, the length of the slot 108 can be approximately 55-65 mm. However, it will be understood that different frequency bands can be implemented by appropriately setting the size of the slot 108 without departing from the scope of this disclosure. In the example shown, slot 108 is Z-shaped, but in other examples, slot 108 may alternatively be V-shaped, as discussed in more detail below. Furthermore, since slot 108 and the slot antenna provided therefrom are integrated with armature 102, no additional external antenna is required. Moreover, the slot antenna provided by slot 108 is cost-effective and mechanically robust, and does not obstruct light generated within lighting equipment 100 (e.g., by LEDs).

[0044] like Figure 1BAs shown, a PCB 110 including a plurality of LEDs 112 is attached to the inner surface of an armature 102. As discussed above, the PCB 110 can be attached to the armature 102 by screws, bolts, rivets, or other suitable fasteners. In some cases, the PCB 110 can be attached to the armature 102 by an adhesive backing provided along the back side of the PCB 110. In various embodiments, the PCB 110 includes a single-layer rigid PCB on which the LEDs 112 are mounted. In some alternative embodiments, the PCB 110 may include a single-layer flexible PCB, a multi-layer rigid PCB, or a multi-layer flexible PCB. The LEDs 112 collectively define an array or linear array of LEDs 112 providing a light source for the lighting device 100. In some embodiments, the LEDs 112 include surface-mount LEDs (SMD LEDs) electrically coupled to conductive traces on the PCB 110. As described above, the PCB 110 having an array of LEDs 112 provides an LED strip PCB (or LED PCB). As described in more detail below, in addition to the array of LEDs 112, a radio communication module (or radio chip) is also mounted on PCB 110. As shown, PCB 110 is attached to armature 102 near slot 108 such that PCB 110 covers at least a portion of slot 108 (e.g., in some cases, half of slot 108) to provide capacitive and / or inductive coupling between the coupling structure on PCB 110 and slot 108. Figure 1A Includes dashed line 110A, which corresponds to PCB 110 and more clearly shows an example of PCB 110 covering at least a portion of the slot 108. In various embodiments, PCB 110 may include additional components such as drivers, matching networks and / or filter networks, coplanar coupling structures, other circuit systems, etc. Further, in some instances, lighting fixture 100 may include other components such as heat sinks, power connections, other hardware or electrical components or circuits, etc.

[0045] refer to Figure 1C It shows Figure 1B An enlarged view of a portion of the lighting equipment, including PCB 110 and an array of LEDs 112. Similarly... Figure 1CAs illustrated, a radio communication module 114 (or radio chip 114) is mounted on a PCB 110. For example, the radio chip 114 may be mounted on the PCB 110 to be electrically coupled to multiple conductive traces on the PCB 110. In some embodiments, the radio chip 114 is coupled via conductive traces on the PCB 110 to one or more LED drivers 116 mounted on the PCB 110, and the LED drivers 116 are further coupled (e.g., via conductive traces on the PCB 110) to an LED 112 to drive the LED 112. As shown, the radio chip 114 is also coupled to a matching network and / or a filter network 118. As discussed in more detail below, the matching network and / or filter network 118 is further connected to coupling traces provided by the conductive traces on the PCB 110. In various embodiments, PCB 110 capacitively and / or inductively feeds the slot antenna (provided by slot 108) through a coplanar coupling structure (coupling trace) on PCB 110, the coplanar coupling structure (coupling trace) being connected to a matching network and / or a filter network 118 and parallel to the surface of armature 102. Additionally, as shown, PCB 110 may cover at least a portion of slot 108.

[0046] For example, the radio chip 114 is a system-on-a-chip (SoC) with multiple components, such as an integrated radio module (operating between approximately 2.4-2.5 GHz), a microcontroller, a power management unit, memory, an integrated balun and RF filter, and a security engine. In some embodiments, the integrated radio module supports multiple communication protocols such as Bluetooth Low Energy and IEEE 802.15.4 communication. In some instances, the radio chip 114 also includes interfaces such as a pulse width modulation (PWM) interface and an internal integrated circuit (I2C) interface (e.g., an analog-to-digital converter interface, a universal synchronous receiver-transmitter interface, and a serial peripheral interface) for generating PWM and I2C signals (which can be used to control the LED driver 116). Typically, and in various embodiments, the radio chip 114 may include a multi-standard low-power communication controller, which can be deployed in any of multiple IoT end-node applications, such as connected lighting devices, sensors, smart plugs, thermostats, or wearable devices. Additionally, and in some embodiments, the radio chip 114 may include GaN-based devices and / or circuitry, such as GaN-based depletion-mode devices and circuitry. For example, in various instances, such GaN-based devices and circuitry may include power amplifiers (PAs), switches, mixers, low-noise amplifiers (LNAs), filters, duplexers, multiplexers, modulators, multipliers, transceivers, or other GaN-based circuitry and / or devices.

[0047] Now for reference Figure 2 The image shows a more detailed top view of a portion of the PCB 110 mounted on the armature 102. Figure 2 Examples also demonstrate fasteners 202 (e.g., screws, bolts, rivets) used to mechanically, rather than electrically, attach PCB 110 to armature 102. Additionally, Figure 2 Various conductive traces on PCB 110 are shown. For example, conductive trace 204 is provided for mounting the array of LEDs 112 described above. Conductive trace 205 is also provided for radio chip 114, matching network and / or filter network 118, coplanar coupling structure (coupled trace), and other associated features, as described in more detail below. In various embodiments, a tinning process (e.g., by electroplating, immersion, or chemical tinning) may be performed before subsequent soldering of LEDs 112, radio chip 114, passive devices (e.g., resistors, capacitors, inductors), or other electronic components to protect conductive traces 204, 205 from oxidation.

[0048] Specifically, Figure 2 An exemplary length 'L1' associated with slot 108 is shown. In an embodiment, length 'L1' may be equal to approximately 57.8 mm. In some cases, length 'L1' may be in the range of approximately 55-60 mm. Also shown... Figure 2The exemplary length 'L2' of the diagonal portion of the Z-shaped slot 108. In some embodiments, length 'L2' may be equal to about 5 mm. In some cases, length 'L2' may be in the range of about 4.5-5.5 mm. In some cases, length 'L2' may be even longer, assuming that length 'L1' has also been adjusted accordingly, as described below. In some instances, the exemplary width 'W' of slot 108 may be equal to about 2 mm. In some cases, width 'W' may be in the range of about 1.5-2.5 mm. In some embodiments, the total (or electrical) length of slot 108 may be equal to L1+L2, wherein the total (or electrical) length is measured along the centerline of slot 108. As previously discussed, the length of slot 108 will determine the frequency band of the slot antenna provided by slot 108. For a desired (or target) frequency band of about 2.4-2.5 GHz, the total (or electrical) length of the slot may be about 55-65 mm. Typically, the total (or electrical) length of slot 108 can be varied such that slot 108 resonates in the target frequency band. In some cases, one or both of lengths L1 and L2 can be varied such that slot 108 resonates in the target frequency band. As an example, consider a length 'L2' equal to or greater than about 10 mm. In such examples, and assuming that the desired frequency band of slot 108 remains constant (e.g., about 2.4-2.5 GHz), the length 'L1' can be reduced accordingly to maintain the total length (L1+L2) of slot 108 suitable for providing the target frequency band.

[0049] Figure 2 The alignment between PCB 110 and slot 108 is further illustrated. In some embodiments, PCB 110 covers approximately half of slot 108, with the other half of slot 108 adjacent to PCB 110. Therefore, as shown in the illustrated example, the edge 210 of PCB 110 can pass through the diagonal portion of the Z-shaped slot 108, thereby substantially bisecting slot 108. It is certain that in various embodiments, PCB 110 does not need to cover exactly half of slot 108. For example, as discussed further below, a misalignment of approximately + / - 1 mm between PCB 110 and slot 108 will still provide an efficient and robust slot antenna. In at least some cases, a misalignment of up to approximately + / - 2 mm between PCB 110 and slot 108 may still provide an antenna with good efficiency.

[0050] refer to Figure 3 This shows a simplified top view illustrating the electrical / RF schematic of the components used for coupling to the PCB 110 of slot 108. More specifically, Figure 3The diagram illustrates conductive traces (conductive traces 205) of PCB 110 for coupling to a slot antenna provided by a slot 108 formed within armature 102, and components formed thereon. As shown, conductive trace 205 includes a first coupling trace 205A and a second coupling trace 205B, wherein the length of each of the first coupling trace 205A and the second coupling trace 205B is approximately one-quarter of the radiation wavelength in the desired (or target) frequency band. In some embodiments, coupling trace 205B may be a ground trace. As previously stated, the total length of slot 108 is approximately half the radiation wavelength in the desired (or target) frequency band. In various examples, conductive traces 205 (located on PCB 110) define a first conductive plane, and a metal backplate of armature 102 defines a second conductive plane parallel to and separated from the first conductive plane by a distance substantially equal to the thickness of the insulating substrate of PCB 110.

[0051] Figure 3 A radio chip 114 is also shown mounted on PCB 110 and coupled to conductive trace 205. In some embodiments, radio chip 114 includes an RF terminal 114A providing the RF output of radio chip 114. RF terminal 114A may include an integrated balun and RF filter, and the output of RF terminal 114A may have an impedance of approximately 50 ohms. In various embodiments, a matching network and / or filter network 118 is electrically coupled to RF terminal 114A (to the RF output of radio chip 114) via conductive traces on PCB 110. In some embodiments, and if desired, radio chip 114 may be placed at a distance further from the slot antenna provided by slot 108 by using a 50-ohm transmission line.

[0052] As shown, the matching network and / or filter network 118 is further coupled to a coplanar coupling structure (coupling trace 205A). In various embodiments, and as previously described, the PCB 110 capacitively and / or inductively feeds the slot antenna (provided by slot 108) through the coplanar coupling structure (coupling trace 205A), which is connected to the matching network and / or filter network 118 and parallel to the surface of the armature 102. In the example of the Z-slot 108 shown, there may be a situation where the transmitter signal is coupled to a general-purpose input / output (GPIO) trace 209 parallel to the coupling trace 205B and connected to the radio chip 114. Figure 4 This generates some stray signals (harmonics). The nonlinear behavior of GPIO circuit systems can introduce harmonics into the transmitted signal. This effect has been shown to result in a limited margin of approximately 6 dB for European Telecommunications Standards Institute (ETSI) and Federal Communications Commission (FCC) certifications. Therefore, refer to the following... Figure 5 In more detail, in some cases, the V-groove 109 can be implemented to minimize coupling from the GPIO trace 209, which is not part of the feed structure (the coplanar coupling structure provided by the coupling trace 205A). In other words, the V-groove 109 is used to keep RF energy away from the GPIO trace 209, thereby reducing the risk of spurious signals. In some embodiments, by implementing the V-groove 109, the certification margin can be increased to about 10 dB without any loss in antenna efficiency. In various embodiments, and regardless of whether the Z-groove 108 or the V-groove 109 is used, about -3 dB of antenna efficiency can be provided.

[0053] refer to Figure 4 The image shows a more detailed top-view perspective of a portion of the PCB 110 mounted on the armature 102. Figure 4 Examples show fasteners 202 (e.g., screws, bolts, rivets) used to mechanically, rather than electrically, attach PCB110 to armature 102. Figure 4 Various conductive traces on PCB 110 are also shown, such as conductive trace 204 for mounting an array of LEDs 112. As previously mentioned, conductive trace 205 is also provided. Specifically, in addition to the coupling traces 205A and 205B discussed above, conductive trace 205 can provide coverage and pin connection areas 206 for the radio chip 114, programming and debug connection area 208, and power and input / output (I / O) area 212. In some embodiments, GPIO trace 209 or at least some GPIO traces 209 can be routed through programming and debug connection area 208 to couple the radio chip 114 to the power and I / O area 212. Figure 4 In one example, slot 108 is also shown as being located in the plane of armature 102 below PCB 110.

[0054] Figure 5 Another top perspective view shows a portion of PCB 110 mounted on armature 102. Figure 5 Examples show fastener 202 and conductive traces, such as conductive trace 204 for mounting an array of LEDs 112. Figure 5 The coverage area and pin connection area 206, programming and debugging connection area 208, and power and I / O area 212 of the radio chip 114 are also shown, as referenced above. Figure 4 The discussion focuses on this. However, compared to the Z-groove 108 shown in the previously described example, Figure 5Examples include a V-groove 109 integrated with the armature 102 and located below the PCB 110. In some embodiments, the angle θ defined by the V-groove 109 can be approximately 45 degrees. More generally, in some embodiments, the angle θ can be in the range of approximately 40-50 degrees. Further, in at least some embodiments, the angle θ can be as high as 90 degrees or typically in the range of approximately 45-90 degrees. For larger values ​​of θ, and in some cases, antenna properties (e.g., impedance, bandwidth, and / or efficiency) can be altered. By using the V-groove 109, undesirable coupling to the GPIO trace 209 (and / or undesirable coupling from other electronic circuitry present in the PCB 110 that is not part of the feed structure) can be minimized. In other words, by implementing the V-groove 109, the undesirable generation and radiation of spurious signals (harmonics) are reduced, thereby improving the robustness of the system (e.g., for electromagnetic compliance regulation). In some embodiments, and similar to the Z-groove 108, the PCB 110 may cover about half of the V-groove 109, while the other half of the V-groove 109 is adjacent to the PCB 110 (although farther from the PCB 110 than the other half of the Z-groove 108 adjacent to the PCB 110).

[0055] Now go to Figure 6-10 The document presents various exemplary simulation results of lighting fixtures, including the Z-slot 108 as described above and the attached PCB 110, according to some embodiments. Specifically, Figure 6 A top perspective view of a portion of PCB110 mounted on armature 102 is shown, wherein armature 102 includes Z-slot 108. Figure 6 An exemplary two-dimensional (2D) far-field plot 602 overlaid on slot 108 is also shown, providing a 2D graphical representation of the radiation pattern of the slot antenna (provided by the Z-shaped slot 108) in the region above the slot antenna. As shown, the radiation emitted by the slot antenna in the plane (the plane of slot 108) away from armature 102 is substantially uniform in all directions.

[0056] Figure 7 A top perspective view of a portion of a PCB 110 mounted on an armature 102 is shown, wherein the armature 102 includes a Z-slot 108. Figure 7 An exemplary three-dimensional (3D) far-field plot 702 overlaid on slot 108 is also shown, providing a 3D graphical representation of the radiation pattern of the slot antenna (provided by the Z-shaped slot 108) in the region above the slot antenna. In this example, 3D far-field plot 702 may correspond to the 2D far-field plot 602 discussed above. 3D far-field plot 702 further emphasizes that the radiation emitted by the slot antenna in the plane (the plane of slot 108) away from armature 102 is substantially uniform in all directions.

[0057] Figure 8A cross-sectional view of PCB 110 mounted on armature 102 is shown, wherein armature 102 includes Z-slot 108. Figure 8 An exemplary 3D far-field map 802 covering the slot 108 is also shown. Specifically, in Figure 8 In one example, the 3D far-field plot 802 provides a 3D graphical representation of the radiation pattern of the slot antenna (provided by the Z-shaped slot 108) in the regions above and below the slot antenna. Although Figure 6-7 Not explicitly shown, but it will be understood that, as with any slot antenna, radiation will be emitted from both sides of the slot. In this example, the 3D far-field diagram 802 may correspond to the 3D far-field diagram 702 and the 2D far-field diagram 602 discussed above. The 3D far-field diagram 802 also shows that the radiation emitted by the slot antenna from a plane away from the armature 102 (the plane of the slot 108) and on both sides of the armature 102 (e.g., above and below the armature 102) is substantially uniform in all directions.

[0058] Figure 9 Showing the corresponding Figure 8 An exemplary 2D far-field map 902 (or gain map) of the 3D far-field map 802. Specifically, the 2D far-field map 902 may correspond to... Figure 8 The 3D far-field diagram 802 is a cross-section, thus providing the radiation pattern of the slot antenna (provided by the Z-shaped slot 108) in the regions above and below the slot antenna, as well as a 2D graphical representation cut along the 2D cross-section of the 3D far-field diagram 802. Again, and in this example, the 2D far-field diagram 902 also shows that the radiation emitted by the slot antenna in the plane (the plane of the slot 108) away from the armature 102 and on both sides of the armature 102 (e.g., above and below the armature 102) is substantially uniform in all directions.

[0059] refer to Figure 10 The example S-parameter diagram 1002 (or return loss diagram 1002) is shown according to some embodiments. As illustrated, the S-parameter diagram 1002 includes S11 parameters plotted according to different values ​​of misalignment between PCB 110 and slot 108, as referenced above. Figure 2 The discussion is ongoing. For reference, bar 1005 is provided, where bar 1005 is the limit line for the -6dB reflection coefficient within the Industrial Science and Medical (ISM) band (2.4–2.48 GHz). Figure 10 As shown, S-parameter graph 1002 includes curve 1004 corresponding to a -1mm offset in the Y direction, curve 1006 corresponding to a -0.5mm offset in the Y direction, curve 1008 corresponding to a 0mm offset in the Y direction, and curve 1010 corresponding to a 0.5mm offset in the Y direction. For the purposes of this discussion, it will be assumed that... Figure 2The example provided corresponds to a 0mm offset in the Y direction, where the edge 210 of PCB 110 passes through the diagonal portion of the Z-slot 108 and substantially bisects the slot 108 (e.g., covering half of the slot 108). According to this example, an offset in the negative Y direction (or misalignment between the edge 210 of PCB 110 and the slot 108) would correspond to the case where PCB 110 covers less than half of the slot 108, while an offset in the positive Y direction would correspond to the case where PCB 110 covers more than half of the slot 108. For a -1mm offset in the Y direction (curve 1004), the slot antenna has a resonant frequency just below 2.38GHz (approximately 2.37GHz); for a -0.5mm offset in the Y direction (curve 1006), the slot antenna has a resonant frequency of approximately 2.42GHz; for a 0mm offset in the Y direction (curve 1008), the slot antenna has a resonant frequency of approximately 2.45GHz; and for a 0.5mm offset in the Y direction (curve 1010), the slot antenna has a resonant frequency of approximately 2.46GHz. In various embodiments, and considering... Figure 10 The exemplary simulation results clearly demonstrate that the disclosed slot antenna can still present matched impedance, even for such large manufacturing tolerances (e.g., misalignment tolerances). In other words, a robust slot antenna can still be provided even with some misalignment between PCB110 and slot 108. Furthermore, although Figure 10 The examples provide data on offsets in the Y direction, but it will be understood that a robust slot antenna can be similarly provided for offsets in the X direction and for offsets in the Z direction (e.g., for slight separation between PCB 110 and armature 102).

[0060] The foregoing has outlined features of several embodiments, enabling those skilled in the art to better understand aspects of this disclosure. Those skilled in the art will recognize that they can readily use this disclosure as the basis for designing or modifying other processes and structures to achieve the same purposes and / or realize the same advantages of the embodiments described herein. Those skilled in the art will also recognize that these equivalent constructions do not depart from the spirit and scope of this disclosure, and that various changes, substitutions, and alternatives can be made without departing from the spirit and scope of this disclosure.

Claims

1. A lighting device comprising: A printed circuit board (PCB) comprising a plurality of light-emitting diodes (LEDs) mounted on the PCB; A radio communication module, which is mounted on the PCB; as well as A coplanar coupling structure, wherein the coplanar coupling structure is coupled to the radio communication module; The PCB is configured to feed the slot antenna through the coplanar coupling structure, and the slot antenna is positioned parallel to and separate from the coplanar coupling structure.

2. The lighting device according to claim 1, further comprising: A metal armature, the metal armature including an opening defining a slot, wherein the slot provides the slot antenna; The PCB is mechanically attached to the metal armature.

3. The lighting device according to claim 2, wherein the slot comprises a half-wavelength slot.

4. The lighting device of claim 2, wherein the metal armature is configured to provide a radiator for the slot antenna.

5. The lighting device according to claim 2, wherein the slot comprises a Z-shaped slot or a V-shaped slot.

6. The lighting device according to claim 1, wherein the PCB comprises a single-layer rigid PCB.

7. The lighting device of claim 2, wherein the mechanically attached PCB covers about half of the slot.

8. The lighting device of claim 1, wherein the PCB is configured to capacitively or inductively feed the slot antenna through the coplanar coupling structure.

9. The lighting device according to claim 1, further comprising: An LED driver is mounted on the PCB, wherein the LED driver is coupled to the radio communication module and to the plurality of LEDs to drive the plurality of LEDs.

10. The lighting device according to claim 1, further comprising: A matching network, which is coupled to the coplanar coupling structure and to the output of the radio communication module.

11. The lighting device of claim 1, wherein the coplanar coupling structure comprises a coupling trace, the coupling trace comprising a conductive trace of the PCB.

12. A lighting device comprising: An armature, the armature including a slot integral with the armature, wherein the slot provides a slot antenna; A light-emitting diode (LED) light strip printed circuit board (PCB), the LED light strip PCB being mechanically attached to the armature; A radio chip, which is mounted on the LED strip PCB and coupled to a coupling trace defined by the conductive traces of the LED strip PCB; and The LED strip PCB is configured to feed the slot antenna capacitively or inductively through the coupling trace.

13. The lighting device of claim 12, wherein the coupling trace defines a first conductive plane, and wherein the armature defines a second conductive plane parallel to the first conductive plane and separated from the first conductive plane by a distance substantially equal to the thickness of the insulating substrate of the LED strip PCB.

14. The lighting device according to claim 12, wherein the slot comprises a Z-shaped slot or a V-shaped slot.

15. The lighting device according to claim 12, wherein the LED strip PCB comprises a single-layer rigid PCB.

16. The lighting device of claim 12, wherein the LED strip PCB covers about half of the slot.

17. The lighting device of claim 12, wherein the radio chip includes a radio frequency (RF) terminal that provides an RF output of the radio chip, and wherein the RF output is coupled to the coupling trace.

18. The lighting device of claim 17, wherein a matching network is coupled between the RF output and the coupling trace.

19. A lighting device comprising: An armature, the armature including a Z-shaped slot providing a slot antenna; and A printed circuit board (PCB) is attached to the armature and covers approximately half of the Z-groove; The PCB includes an array of light-emitting diodes (LEDs), an LED driver coupled to the array of LEDs to drive the LEDs, and a radio chip coupled to the LED driver and coupled to a matching network, the matching network being connected to the output of the radio chip; The matching network is further coupled to the conductive coupling traces of the PCB; and The PCB is configured to capacitively or inductively feed the Z-groove through the conductive coupling traces.

20. The lighting device of claim 19, wherein the Z-groove has a first length equal to about half the wavelength of the target frequency, and wherein the conductive coupling trace has a second length equal to about one-quarter the wavelength of the target frequency.

Images