Patent Application
20230060856
A wireless apparatus, such as a wireless microphone, needs some form of antenna to transmit and/or receive wireless signals. However, the antenna typically is made up of additional components that add to the manufacturing cost and complexity and that take up extra space internal or external to the apparatus. Moreover, with an external antenna, the wireless apparatus often requires additional mechanical protection to prevent damage to the antenna if the apparatus is dropped, further increasing product cost and complexity.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the disclosure.
A wireless apparatus utilizes an antenna comprising one or more elements (which may each be an electrically conductive element, e.g., each be made of an electrically conductive material such as a metallic material, and/or a non-metallic conductive material such as graphite) that contributes to antenna functionality, in which the at least one element also supports a mechanical (e.g., structural) feature, an electrical circuit feature, and/or an ornamental feature. When one or more such elements are incorporated into an antenna, the element(s) may also continue to support its/their original feature(s). Each element may include, for example, a chassis, grille, label, housing, trim, battery casing, printed circuit board (PCB) ground plane, electrolytic capacitor casing, attachment clip, and so forth.
According to some aspects of the present disclosure, a transceiver, transmitter, or receiver of a wireless apparatus generates and/or receives a radio frequency (RF) signal to and/or from an antenna comprising one or more elements and that may be configured to operate within a specific frequency band. The frequency band may be any frequency band. For example, the frequency band may be appropriate to support Bluetooth® or WiFi® services.
According to further aspects of the disclosure, the antenna for the wireless apparatus may support a dipole antenna. The dipole antenna may comprise at least two elements such as a first element and a second element, where each of the first and second elements corresponds to a respective different half of the dipole. For a half wave dipole, for example, each of the first and second elements may be approximately a quarter wavelength along one of its dimensions. A transceiver, transmitter, or receiver may be electrically connected to each of the two elements via an electrically conductive connection such as a metal screw, metal spring, wire, cable, and so forth.
According to further aspects of the disclosure, the antenna for the wireless apparatus may be an inverted-F antenna. The inverted-F antenna may comprise at least one element such as a first element, where the first element may be, for example, approximately a quarter wavelength along one of the antenna's dimensions. A transceiver, transmitter, or receiver may be electrically connected to the element at a feed point of the antenna, while one end of the element may be electrically connected to a grounding point of the wireless apparatus.
According to further aspects of the disclosure, a wireless microphone utilizes an antenna that may comprise a first element (such as a grille assembly of the wireless microphone) and a second element (such as a chassis housing of the wireless microphone), where the grille assembly and the chassis housing may be electrically separated by an electrical insulator. The RF output of a transmitter of the wireless microphone may be electrically connected to the grille assembly while a grounding point of the transmitter may be electrically connected to the chassis housing.
According to further aspects of the disclosure, a matching circuit may be inserted between an antenna and a transmitter to help match the impedance of the antenna and the output impedance of the transmitter. Similarly, a matching circuit may be inserted between an antenna and a receiver to help match the impedance of the antenna and the input impedance of the receiver. Similarly, a matching circuit may be inserted between an antenna and a transceiver (which may include the above-mentioned transmitter and receiver) to help match the impedance of the antenna and the input and/or output impedances of the transceiver.
A more complete understanding of the exemplary embodiments of the present invention and the advantages thereof may be acquired by referring to the following description in consideration of the accompanying drawings, in which like reference numbers indicate like features and wherein:
In the following description of the various exemplary embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration various embodiments in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention.
A wireless apparatus (for example, a wireless microphone) may utilize an antenna comprising at least one element (component), which also supports a mechanical feature, an electrical circuit feature, or an ornamental feature. When an element is incorporated into an antenna, the element may also continue to support its original feature unrelated to the function of the antenna. In other words, a particular portion (an electrically conductive element) of the wireless apparatus supports both the original feature for which the portion is intended as well as an antenna feature. An element may assume different forms, including but not limited to, a chassis, grille, label, housing, trim, battery casing, printed circuit board (PCB) ground plane, electrolytic capacitor casing, attachment clip, and the like.
It may be desirable to support a small portable wireless microphone (such as wireless microphone 100) with an integrated Bluetooth® or other transceiver with a metal form factor for mobile wireless audio/visual capabilities and/or recording applications. A metal form factor may provide quality construction and improved durability; however, a metal form factor may also interfere with an antenna internal to the microphone by absorbing or reflecting radio frequency waves that would otherwise be received by the internal antenna or that would be transmitted via the antenna. Thus, it is not unusual for metal-housed radio circuitry to use external antennas with one or more physical radiating elements external to the housing. However, such external antennas can be less durable and cause the microphone to be larger than desirable. In order to reduce portable transceiver size and/or maximize durability, rather than using traditional external radiating antenna elements, the electrically conductive (e.g., metal) microphone grille (such as grille 102), electrically conductive (e.g., metal) circuit chassis assembly (such as chassis assembly 101), and/or other electrically conductive (e.g., metal) parts of the microphone that already serve other purposes (such as by housing portions of the microphone) may be used to form one or more antenna elements. For example, grille 102 and chassis assembly 101 may each be used as dipole antenna elements of an antenna of microphone 100.
Chassis assembly 101 and grille 102 may be used to form an antenna such as a dipole antenna (for example, a 2.4 GHz dipole antenna) by, for example, feeding an RF signal internally generated by the circuitry of microphone 100 to the grille assembly 102 through electrical connection 106 and grounding the internal RF circuit boards on PCB 104 to the chassis assembly 101 through electrical connection 105. Grille 102 and chassis assembly 101 may be electrically isolated from each other by insulator 103.
The antenna of wireless microphone 100 may be, for example, a half wave dipole antenna (where each element is approximately a quarter wavelength in one dimension), a harmonic dipole antenna (operational at odd harmonics of the fundamental frequency of a half wave dipole), an inverted-F antenna, and/or any other type of antenna. (A dipole antenna is a class of antennas producing a radiation pattern approximating that of an elernentaty electric dipole. An inverted-F antenna roughly corresponds to a shape of an inverted letter “F” and comprises a monopole antenna running parallel to a ground plane and grounded at one end. The inverted-F antenna is typically fed from an inter ediate point at a distance from the grounded end.)
The antenna of wireless apparatus 100 may utilize, for example, its largest structural feature(s) (such as the grille assembly 102 and/or chassis assembly 101) as antenna elements, potentially providing increased antenna bandwidth over other small form factor antennas. The larger the element, the smaller the Q (corresponding an increased frequency bandwidth) that may be expected. The increased bandwidth may reduce the effects of antenna detuning when the microphone is handled or transferred to a mic clip.
Such a grille-chassis antenna (comprising, in this example, chassis assembly 101 and grille assembly 102) may be configured as a dipole antenna structure, and may have a sufficiently high radiation efficiency and/or increased transmission and/or reception range in numerous typical performance applications.
The antenna (such as the grille-chassis antenna) may be adapted to one or multiple frequency bands as desired such as, but not limited to, 2.4 GHz (corresponding to Bluetooth® and/or WiFi® services) and/or 5.8 GHz (corresponding to WiFi services). Where a selected element has a dimension (length, width, or depth) of approximately λ/4, then it may be expected that λ. is the wavelength of operation. However, when the Q of an element is lower (for example, with a greater width), the approximation to λ/4 may be relaxed.
When chassis assembly 101 comprises a non-conductive material (for example, plastic), a grille-ground plane antenna may be formed from grille assembly 102 and a ground plane of PCB 104 (rather than chassis assembly 101), where the ground plane has at least one dimension of approximately λ/4 and where λ is the wavelength of operation. Different antenna configurations may be supported by the grille-ground plane antenna. For example, grille assembly 102 and the ground plane may each correspond to a half of a dipole antenna.
An illustrative embodiment for
If the antenna comprising elements 202 and 203 is not sufficiently matched to transceiver 201, matching circuit 204 may be inserted between transceiver 201 and element 202. For example, transceiver 201 may be implemented with a particular output impedance such as 50 ohms. If the antenna impedance is 25 ohms, the resulting voltage standing wave ratio (VSWR) is approximately 2. To reduce the VSWR, matching circuit 204 may be configured to match 50 ohms to 25 ohms. However, if the antenna has an impedance sufficiently close to the transceiver impedance, matching circuit 204 may not be needed for effective operation. For example, referring to
As previously mentioned, the grill-chassis antenna may be configured as a dipole antenna with microphone grille 102 forming one portion (e.g., one half and may be referred to as a first antenna feature) of the dipole and chassis assembly 101 forming the other portion (e.g., the other half and may be referred to as a second antenna feature). However, as will be discussed, other types of antennas may be formed, such as an inverted-F antenna.
A transceiver, transmitter, or receiver (not explicitly shown) may be mounted on PCB 502a and may be electrically connected to the inverted-F antenna through one or more electrical connections 551a and/or 552a. Connections 551a and 552a may comprise, for example, metallic screws, and may be configured as an antenna feed point and an antenna shorting pin, respectively.
Various aspects described herein may be embodied as a method, an apparatus, or as computer-executable instructions stored on one or more non-transitory and/or tangible computer-readable media. Any and/or all of the method steps described herein may be embodied in computer-executable instructions stored on a computer-readable medium, such as a non-transitory and/or tangible computer readable medium and/or a computer readable storage medium. Additionally or alternatively, any and/or all of the method steps described herein may be embodied in computer-readable instructions stored in the memory and/or other non-transitory and/or tangible storage medium of an apparatus that includes one or more processors, such that the apparatus is caused to perform such method steps when the one or more processors execute the computer-readable instructions. In addition, various signals representing data or events as described herein may be transferred between a source and a destination in the form of light and/or electromagnetic waves traveling through signal-conducting media such as metal wires, optical fibers, and/or wireless transmission media (for example, air and/or space).
Aspects of the disclosure have been described in terms of illustrative embodiments thereof. Numerous other embodiments, modifications, and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure. For example, one of ordinary skill in the art will appreciate that the steps illustrated in the illustrative figures may be performed in other than the recited order, and that one or more steps illustrated may be optional in accordance with aspects of the disclosure.
8. The wireless microphone of clause 1, wherein the antenna is configured to operate in an RF spectrum between 5 GHz to 6 GHz.
This application claims priority to provisional Application No. 63/236,433 filed Aug. 24, 2021, which is incorporated by reference in its entirety herein.
| Number | Date | Country | |
|---|---|---|---|
| 63236433 | Aug 2021 | US |
