Patent Application
20240136711
The present disclosure generally relates to antenna systems and methods. More specifically, the present disclosure relates to an integrated sheet-metal antenna with mechanically supported carrier screw which operates as a ground feed for the antenna and provides mechanical support in the electronic device.
Various devices utilize antennas for wireless communication, such as wireless Access Points (APs), streaming media devices, laptops, tablets, and the like (collectively “wireless devices”). Recently, the demand for antennas for mobile wireless applications has increased dramatically, this is driven in part by the Internet of Things (IoT) market. IoT devices include sensors, processing ability, and software applications that connect and exchange data with other devices over the internet or other similar communication networks. Every IoT device requires at least one antenna, and since IoT devices are expected to operate with many different devices at many different frequency bands, IoT devices can include multiple antennas in one small form device.
There exist many ways of implementing antennas into a wireless product. The typical existing implementing means include printed circuit board (PCB), flexible PCB (flex PCB), using metallic enclosures themselves, laser direct structuring (LDS), and stamped metal-sheet. Stamped metal-sheet antennas can be surface mounted on a PCB, which in the industry is known as surface mount technology (SMT). An electronic component mounted in this manner is referred to as a surface mount device (SMD). This SMT approach replaced the through-hole technology (THT) mainly because it is better suited for automated assembly techniques. The typical soldering technique used in SMT is reflow soldering wherein a solder paste is used temporarily to attach component(s) to their contact pads, after the entire assembly is heated and the solder reflows in a molten state creating the permanent solder joints. Stamped metal-sheet antennas can also be connected to the PCB by screws between the antenna and the PCB or attaching the antenna to a component carrier. A component carrier acts as a connecting element between a PCB and the antenna and can provide benefits such as ease of replacement and reducing assembly time and costs. The stamped metal-sheet antenna implementation requires mechanical support for the antenna, this can be accomplished by the SMT connection to the PCB, screwing the antenna to the PCB, or attaching it to a component carrier.
The challenge with implementing metal-sheet antennas into a small form wireless device compared to other antenna types such as PCB, flex PCB, or LDS is that the metal sheet requires a mechanical supporting means as it is not embedded in another stable component such as a trace on a PCB. As antenna design gets more complex and implemented into smaller form devices eliminating unnecessary components or combining functionality of multiple components into fewer elements frees up space inside the enclosure and also makes assembly and fabrication faster and less expensive. This drive for efficient use of interior space combined with a continued desire to automate assembly is especially evident with fasteners such as screws. Many small screws can require robotic assemblers to move in the horizontal and vertical direction in addition to a rotational movement to achieve the fastening. If fasteners such as screws can be reduced in the assembly, it can result in not only a cost savings but also a potential to add additional devices such as additional antennas that would not otherwise be possible.
The present disclosure includes an antenna for an electronic device comprising of a metal-sheet antenna and an antenna feed connecting the metal-sheet antenna to a radio frequency (RF) printed circuit board (PCB). A screw configured to operate as a ground feed for the metal-sheet antenna and to provide mechanical support in the electronic device wherein the screw is further configured to provide radiation for additional bands for the antenna.
This section will be the CLAIMS at the end rewritten in paragraph form once finalized
The present disclosure is illustrated and described herein with reference to the various drawings, in which like reference numbers are used to denote like system components/method steps, as appropriate, and in which:
Again, the present disclosure includes an antenna for an electronic device comprising of a metal-sheet antenna and an antenna feed connecting the metal-sheet antenna to a radio frequency (RF) printed circuit board (PCB). A screw configured to operate as a ground feed for the metal-sheet antenna and to provide mechanical support in the electronic device wherein the screw is further configured to provide radiation for additional bands for the antenna.
IoT (smart) devices typically utilize frequency bands for short range and mid-range connectivity. There exist several applications for wireless communications that require a wide range of frequency bands. Short range connectivity is most common in IoT applications and include protocols such as Bluetooth and Zigbee (2.4 GHz to 2.485 GHz), Near-Field Communication (NFC) (13.56 MHz), Wi-fi (2.4 GHz to 5 GHz), and 5G (5.15 GHz to 5.85 GHz). Ultra-wideband (UWB) can utilize a large frequency band (3.1 GHz to 10.6 GHz) that is broken down into physical bands provided as channels as defined by the WiMedia Alliance PHY specification.
The Matter protocol uses existing standards such as Wi-fi and Bluetooth for initial pairing and thread protocol that connects products from different brands without the need for a hub. Matter operates at 2.4 GHz similar to Wi-fi, Bluetooth, and Zigbee. Matter is new in the industry and is being developed to create a standard communication platform for smart devices to interface with one another.
It should be noted that antenna elements must be physically dimensioned to match the operating wavelength, and antenna size is inversely proportional to frequency, therefore the lower the operational frequency the larger the antenna that is required to operate at that frequency. Small intuitive configurations for antennas to receive radio waves in many different positions is a large part of antenna design in smart devices. Reducing the number of components and combining functionality of antenna components in a smart device can allow antenna designers to utilize the small form space required to operate at multiple frequencies and in multiple positions.
Stamped metal-sheet antennas can be implemented into a wireless device by securing with screws.
In another example, stamped metal-sheet antennas can be implemented into a wireless device by surface mounted on a PCB, which in the industry is known as surface mount technology (SMT). The typical soldering technique used in SMT is reflow soldering which a solder paste is used temporarily to attach component(s) to their contact pads, after the entire assembly is heated and the solder reflows in a molten state creating the permanent solder joints. As illustrated in
In yet another example, stamped metal-sheet antennas can be implemented into a wireless device by glue or heat-staking the metal-sheet to a dielectric carrier 300. A component carrier, or as shown in
In the circuit shown in 400, AC coupling occurs in the screw boss 410 which functions as a parasitic capacitance to the sheet-metal antenna. Parasitic capacitance exists between two nearby conductive elements possess different charge levels such as what occurs between the metallic screw boss 410 and the antenna short 470. Furthermore, the ground screw 450 is integrated into the wireless device to mechanically reinforce the entire structure of the product including PCBs 430 and heat spreaders 420 and 440, etc.). As illustrated the screw 450 and screw boss 410 being metallic allows those components to be used in the antenna circuit as well as provide mechanical support for the antenna circuit. The screw 450 and screw boss 410 are positioned in close proximity to the antenna short 470, this allows the screw boss 410 to couple with the antenna ground, excite the screw boss, and radiate energy and act as part of the antenna circuit. As illustrated in 320, the existing industry antenna implementation 300 depicts the antenna feed and short (320) separate from the screw boss 340. By using this screw boss 410 as part of the antenna short it reduces the number of components used in the wireless device and would save time and money during assembly. Since the screw and screw boss function as a radiating component of the antenna, the antenna can be tuned by manipulating the gap between screw boss 410 and antenna short 470 (referred to in the figure as SBS), manipulating the physical height (SBh) and width (SBl) of the screw boss 410 and manipulating the gap between the screw boss 470 and the antenna short foot 480 (SBg).
The second resonance is controlled by the currents flowing on the screw 840 and the screw boss 870. The dimensions of the screw boss which include diameter, length, width, and height and the screw gap near the screw boss determine the resonance length. The resonant length is quarter wavelength at operating frequency, therefore at 6.5 GHz (UWB channel #5), the Sl, which represents the overall length shown in dotted double arrow line from the screw boss down to the screw, is approximately 11 mm. Sl−SBl/2+SBh+SBg, where SBl (screw boss width), SBh (screw boss height), SBg (gap between the screw boss 470 and the antenna short foot 480) are dimensions as shown in 400. The currents associated with this screw 840 and screw boss 870 are shown in 800. It should be noted that the screw boss 870 is floating and is not in contact with the antenna short or short foot therefore can be considered a passive radiator or a parasitic element. Parasitic elements are conductive elements that are not in electrical contact with anything but will form between any conductive elements that carry a charge, in this case the current is coupled between the screw boss 870 and the antenna short 880, wherein the antenna short provides the charge. The screw is installed in a cavity 860 that exists between the wireless device components such as heat spreaders (810,830) and PCB (820) to keep the screw electrically floating. The current that results from the coupling is directed up the screw 840 into the screw boss in a counterclockwise direction as shown by arrows in 800.
The third resonance is the electric field created by the gap between the screw boss 870/screw 840 and the antenna short element 880. The third resonance is created by the electric field as shown by the arrows between the antenna short element 880 and the screw boss 870. The screw boss 870 and antenna short element 880 is separated by a dielectric such that there is no contact between the two, but the electric field is inducted between the two elements. This third resonance can be controlled by the length GI which is shown as a dotted double arrow line on the illustration 800 which can be adjusted by modifying the screw boss 870 size. Since the screw 840 is installed from the underside of the heat spreader 830 modifying the screw boss would be very easy and not affect other components in the assembly. This circuit configuration acts as an open slot radiator and the resonance length is set to quarter wavelength. To achieve 8 GHz (UWB channel #9) the GI is approximately 9 mm.
The circuit diagram with electrical fields shown in 800 depicts a traditional IFA/PIFA antenna with resonance, the screw 840/screw boss 870 provides a second resonance since it is electrically floating in respect to the PIFA/IFA, and the third resonance is created by the field between the screw boss and the antenna short. By utilizing this screw (which traditionally would be separate from the antenna electrical circuit) into the antenna circuit it not only combines components making assembly less complex, but it also allows multiple antennas acting at multiple frequencies to be utilized from a traditional single PIFA/IFA antenna design. The screw 840 and screw boss 870 can be adjusted to tune the antenna circuit in addition to providing a mechanical support to secure the antenna to the other wireless components such as the heat spreaders (810,830) and the PCB (820).
The three resonances that exist with the antenna configuration shown in 800 are shown on the frequency response graph (900). The first resonance occurs at the PIFA/IFA antenna and can be tuned by controlling the length of the antenna to the desired frequency, in this case the desired frequency is 2.4 GHz to support Bluetooth, Wi-Fi, and Matter (910).
The second resonance is tuned to a desired frequency of 6.5 GHz to support UWB Channel #5 (920). The frequency is achieved by modifying the dimensions of the screw boss. Since the screw and screw boss functions as a radiating component, the antenna can be tuned by manipulating the gap between screw boss 410 and antenna short 470 (SBS), manipulating the height and width of the screw boss 410 (SBl, SBh), and manipulating the gap between the screw boss 470 and the antenna short foot 480 (SBg). The screw boss 710 width can be extended (SPl) and it can be used to tune the antenna circuit. Similarly, AFh represents another adjustment that can be made to the antenna circuit that can provide tuning for the antenna (700). Controlling the second resonance is the most difficult however the screw and screw boss provide many tuning options to achieve the desired frequency and give the antenna designer flexibility for achieving many desired frequencies.
The third resonance can be controlled by the length GI as shown in 800 as a dashed double arrow line and can be adjusted by modifying the screw boss 870 size. The third resonance is tuned to 8 GHz to support UWB Channel #9 (930).
This implementation of the PIFA/IFA antenna allows the three resonance frequencies to be utilized with a much smaller footprint and reduced components such as reducing the number of screws that are required for mechanical support of the metal-sheet antenna. The first resonance is achieved by utilizing the PIFA/IFA antenna 1120. The screw 1110/screw boss 1190 provides a second resonance since it is electrically floating in respect to the PIFA/IFA, and the third resonance is created by the field between the screw boss 1190 and the antenna short 1180. By utilizing this screw (which traditionally would be separate from the antenna electrical circuit) into the antenna circuit it not only combines components making assembly less complex, but it also allows multiple antennas acting at multiple frequencies to be utilized from a traditional single PIFA/IFA antenna design. The screw 1110 and screw boss 1190 can be adjusted to tune the antenna circuit in addition to providing a mechanical support to secure the antenna to the other wireless components.
It will be appreciated that some embodiments described herein may include one or more generic or specialized processors (“one or more processors”) such as microprocessors; Central Processing Units (CPUs); Digital Signal Processors (DSPs): customized processors such as Network Processors (NPs) or Network Processing Units (NPUs), Graphics Processing Units (GPUs), or the like; Field Programmable Gate Arrays (FPGAs); and the like along with unique stored program instructions (including both software and firmware) for control thereof to implement, in conjunction with certain non-processor circuits, some, most, or all of the functions of the methods and/or systems described herein. Alternatively, some or all functions may be implemented by a state machine that has no stored program instructions, or in one or more Application-Specific Integrated Circuits (ASICs), in which each function or some combinations of certain of the functions are implemented as custom logic or circuitry. Of course, a combination of the aforementioned approaches may be used. For some of the embodiments described herein, a corresponding device in hardware and optionally with software, firmware, and a combination thereof can be referred to as “circuitry configured or adapted to,” “logic configured or adapted to,” etc. perform a set of operations, steps, methods, processes, algorithms, functions, techniques, etc. on digital and/or analog signals as described herein for the various embodiments.
Moreover, some embodiments may include a non-transitory computer-readable storage medium having computer readable code stored thereon for programming a computer, server, appliance, device, processor, circuit, etc. each of which may include a processor to perform functions as described and claimed herein. Examples of such computer-readable storage mediums include, but are not limited to, a hard disk, an optical storage device, a magnetic storage device, a ROM (Read Only Memory), a PROM (Programmable Read Only Memory), an EPROM (Erasable Programmable Read Only Memory), an EEPROM (Electrically Erasable Programmable Read Only Memory), Flash memory, and the like. When stored in the non-transitory computer-readable medium, software can include instructions executable by a processor or device (e.g., any type of programmable circuitry or logic) that, in response to such execution, cause a processor or the device to perform a set of operations, steps, methods, processes, algorithms, functions, techniques, etc. as described herein for the various embodiments.
Although the present disclosure has been illustrated and described herein with reference to preferred embodiments and specific examples thereof, it will be readily apparent to those of ordinary skill in the art that other embodiments and examples may perform similar functions and/or achieve like results. All such equivalent embodiments and examples are within the spirit and scope of the present disclosure, are contemplated thereby, and are intended to be covered by the following claims. Moreover, it is noted that the various elements, operations, steps, methods, processes, algorithms, functions, techniques, etc. described herein can be used in any and all combinations with each other.
