This disclosure relates to the field of antennas, and in particular, to a printed antenna.
Currently, increasingly more electronic devices need built-in antennas to transmit and receive signals, and the antennas are generally disposed on a printed circuit board (PCB). When transmitting, the antenna converts a high-frequency current of a transmitter into a spatial electromagnetic wave, and when receiving, the antenna converts an electromagnetic wave intercepted from space into a high-frequency current and sends the high-frequency current to a receiver.
There are many types of antennas, and different applications require different antennas. A loop antenna is a type of antenna commonly used in a low-power and short-range system. The antennas have different radiation modes such as a monopole antenna and an inverted-F antenna, and different radiation modes correspond to different operating frequencies. However, a single radiation mode of the loop antenna cannot achieve relatively high radiation efficiency in different frequency bands, resulting in a relatively small coverage area of an operating frequency of the loop antenna.
Embodiments of this disclosure provide a printed antenna, to improve an operating frequency coverage area and a directivity pattern coverage area of the antenna.
According to a first aspect, an embodiment of this disclosure provides a printed antenna. The printed antenna is printed on a substrate, a feed module is further disposed on the substrate, and the printed antenna includes a loop antenna body, a feed port, and a switch component. The loop antenna body includes a first end and a second end, there is a spacing between the first end and the second end, a connection line between the first end and the second end forms a closed loop with the loop antenna body, the first end is connected to the feed module by using the feed port, and the second end is connected to a ground point (GND). The feed module is configured to output a feed signal to the loop antenna body by using the feed port. The loop antenna body includes a plurality of loop antenna branches, the switch component is disposed between every two adjacent loop antenna branches, and the switch component is configured to connect or disconnect the two adjacent loop antenna branches.
In this implementation, an operating frequency of the loop antenna changes in two different statuses in which the switch component is turned on or off. Therefore, a plurality of operating frequencies and directivity patterns may be covered by adjusting turn-on or turn-off of each switch component, thereby expanding an operating frequency and a directivity pattern coverage mode that can be selected by the antenna.
Optionally, in some possible implementations, each switch component is a 0-ohm resistor. If two ends of the 0-ohm resistor are respectively soldered to two adjacent antenna branches, it indicates that the 0-ohm resistor is in a turn-on state. If two ends of the 0-ohm resistor are not soldered to two adjacent antenna branches, or one end of the 0-ohm resistor is not soldered to one antenna branch, it indicates that the 0-ohm resistor is in a turn-off state.
In this implementation, compared with other types of switch components, the 0-ohm resistor has relatively low costs, and an original BOM on a PCB is minimally changed, so that a development cycle and maintenance costs of the printed antenna can be reduced as much as possible.
Optionally, in some possible implementations, a control module is further disposed on the substrate, and each switch component is a diode. Two ends of each diode are separately connected to a control module by using two bias power cables, and the two ends of the diode are respectively connected to two adjacent antenna branches. The control module controls a voltage drop of the diode to turn on or turn off the diode.
In this implementation, an advantage of using the diode instead of the 0-ohm resistor is that on-off of the diode may be controlled in real time by using the control module, without a need for a worker to change an on-off status by manually soldering the 0-ohm resistor. The operating frequency or a directivity pattern of the antenna may be switched more flexibly.
Optionally, in some possible implementations, the printed antenna further includes a first reflector antenna body, the first reflector antenna body is disposed on one side of the loop antenna body, and the first reflector antenna body is connected to the feed module. The first reflector antenna body includes two first reflector antenna branches, a switch component is disposed between the two first reflector antenna branches, and the switch component located between the two first reflector antenna branches is configured to connect or disconnect the two first reflector antenna branches.
In this implementation, the first reflector antenna body is specifically configured to reflect an electromagnetic wave. Therefore, the directivity pattern of the printed antenna may alternatively be adjusted by controlling the switch component between the two first reflector antenna branches, thereby enriching implementations of this solution.
Optionally, in some possible implementations, the printed antenna further includes a second reflector antenna body, the second reflector antenna body is disposed on the other side of the loop antenna body, and the second reflector antenna body is connected to the feed module. The second reflector antenna body includes two second reflector antenna branches, a switch component is disposed between the two second reflector antenna branches, and the switch component located between the two second reflector antenna branches is configured to connect or disconnect the two second reflector antenna branches.
In this implementation, reflector antenna bodies may be disposed on both sides of the loop antenna body, thereby improving scalability of this solution.
Optionally, in some possible implementations, a switch component is disposed between the second end and the GND, and the switch component located between the second end and the GND is configured to connect or disconnect the second end and the GND.
In this implementation, an operating frequency coverage area and a directivity pattern coverage area of the printed antenna may be further expanded by controlling on-off of the switch component between the second end and the GND.
Optionally, in some possible implementations, the printed antenna includes a first switch component, a second switch component, a third switch component, and a fourth switch component. The loop antenna body includes a first loop antenna branch, a second loop antenna branch, a third loop antenna branch, and a fourth loop antenna branch. One end of the first loop antenna branch is connected to the feed module by using the feed port, and the first switch component is disposed between the other end of the first loop antenna branch and the second loop antenna branch. The second switch component is disposed between the second loop antenna branch and the third loop antenna branch, the third switch component is disposed between the third loop antenna branch and one end of the fourth loop antenna branch, and the fourth switch component is disposed between the other end of the fourth loop antenna branch and the GND.
In this implementation, a structure in which the loop antenna body is divided into four loop antenna branches is described, thereby improving practicability of this solution.
Optionally, in some possible implementations, the first loop antenna branch is a monopole antenna having a single radiation mode, which provides a basis for dividing the loop antenna body, thereby improving feasibility of this solution.
Optionally, in some possible implementations, an operating frequency band of the printed antenna covers an operating frequency band (including 2.4 GHz and 5 GHz) of a wireless local area network (WLAN) standard and an operating frequency band (including 1.6 GHz to 2.2 GHz and 2.3 GHz to 2.7 GHz) of a long term evolution (LTE) standard. Radiation directions of the printed antenna include horizontal omnidirectional, horizontal directional, and vertical coverage.
In this implementation, a plurality of operating frequency bands and directivity patterns that can be covered by the printed antenna are listed, thereby further improving practicability of this solution.
It can be learned from the foregoing technical solutions that the embodiments of this disclosure have the following advantages:
In the embodiments of this disclosure, the loop antenna body includes a plurality of loop antenna branches, and the switch component is disposed between every two adjacent loop antenna branches. Each switch component may connect or disconnect two adjacent loop antenna branches. The operating frequency of the loop antenna changes in two different statuses in which the switch component is turned on or off. Therefore, a plurality of operating frequencies and directivity patterns may be covered by adjusting turn-on or turn-off of each switch component, thereby expanding the operating frequency and the directivity pattern coverage mode that can be selected by the antenna.
Embodiments of this disclosure provide a printed antenna, to expand an operating frequency and a directivity pattern coverage mode that can be selected by the antenna. In this specification, the claims, and the accompanying drawings of this disclosure, terms “first”, “second”, “third”, “fourth”, and the like (if existent) are intended to distinguish between similar objects but do not necessarily indicate a specific order or sequence. It should be understood that data termed in such a way is interchangeable in an appropriate circumstance, so that the embodiments described herein can be implemented in another order than the order illustrated or described herein. Moreover, terms “include”, “comprise”, and any other variants thereof mean to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a list of steps or units is not necessarily limited to those steps or units, but may include other steps or units that are not expressly listed or inherent to such a process, method, product, or device.
A type of the printed antenna is a loop antenna, and the loop antenna has advantages of a small volume, high reliability, and low costs, making the loop antenna an ideal antenna for a miniature communications product. However, a single radiation mode of the loop antenna cannot achieve relatively high radiation efficiency in different frequency bands, resulting in a relatively small coverage area of an operating frequency of the loop antenna.
Therefore, this disclosure provides a printed antenna, to improve an operating frequency coverage area and a directivity pattern coverage area of the antenna.
The loop antenna body 101 may be formed by winding from the first end 101a (or the second end 101b) to the second end 101b (or the first end 101a), and a connection line between the first end 101a and the second end 101b may form a closed loop with the loop antenna body 101. Specifically, a shape of the loop may be a square loop shown in
The loop antenna body 101 includes a plurality of branches, and the switch component 103 is disposed between every two adjacent branches. For example, as shown in
Specifically, each switch component 103 is configured to connect or disconnect two adjacent branches. For example, as shown in
It should be noted that different on-off combinations of switch components may change the directivity pattern of the antenna, in addition to changing the operating frequency of the antenna. The directivity pattern is also referred to as a radiation directivity pattern. The directivity pattern is a pattern in which relative field strength (a normalized modulus value) of a radiation field changes with a direction at a specific distance from an antenna, and is usually represented by using two mutually vertical plane directivity patterns in a maximum radiation direction of the antenna. A directivity pattern mode may include horizontal omnidirectional, horizontal directional, and vertical coverage. The following provides a further description with reference to simulation results of the directivity pattern.
The printed antenna shown in
It should be noted that the switch component in this disclosure may specifically have a plurality of different types, which are separately described below.
Type 1: The switch component is a 0-ohm resistor. If the 0-ohm resistor is soldered to the antenna, the 0-ohm resistor is in a turn-on state. If the 0-ohm resistor is not soldered to the antenna, the 0-ohm resistor is in a turn-off state.
It should be noted that, compared with other types of switch components, the 0-ohm resistor has relatively low costs, and an original BOM on a PCB is minimally changed, so that a development cycle and maintenance costs of the printed antenna can be reduced as much as possible.
Type 2: The switch component is a diode, and the diode is controlled to be turned on or off by using a control module.
It should be noted that, an advantage of using the diode instead of the 0-ohm resistor is that on-off of the diode may be controlled in real time by using the control module, without a need for a worker to change an on-off status by manually soldering the 0-ohm resistor. Switching of the operating frequency or the directivity pattern of the printed antenna is more flexible.
Optionally, in addition to the loop antenna body 101, the printed antenna 10 may further include at least one reflector antenna. The following provides a further description.
The reflector antenna 104a and the reflector antenna 104b are specifically configured to reflect an electromagnetic wave. Therefore, the directivity pattern mode of the printed antenna 10 may be adjusted by disposing the reflector antenna 104a and the reflector antenna 104b and controlling on-off of the switch component 103e and the switch component 103f. For example, an original directivity pattern mode of the printed antenna 10 is horizontal omnidirectional, and if the switch component 103e and the switch component 103f are both turned off, the directivity pattern mode of the printed antenna 10 is still horizontal omnidirectional. If the switch component 103e is turned on and the switch component 103f is turned off, the directivity pattern mode of the printed antenna 10 is right directional. If the switch component 103e is turned off and the switch component 103f is turned on, the directivity pattern mode of the printed antenna 10 is left directional.
It may be understood that the switch component 103e and the switch component 103f may be 0-ohm resistors, or may be diodes. This is not specifically limited herein.
Optionally, a switch component may also be disposed between the second end 101b of the loop antenna body 101 and the ground point 40. The following provides a further description.
Optionally, in addition to the foregoing described embodiment in which the loop antenna body is divided into three antenna branches, the loop antenna body may alternatively be divided into more antenna branches. The following describes an embodiment in which the loop antenna body is divided into four antenna branches.
2.3-3.3G
2.3-3.3G
2.2-3.1G
1.6-2.2G
1.7-2.1G
6.9-8.7G
It should be noted that a quantity of antenna branches obtained by dividing the loop antenna body and a quantity of switch components are subject to an actual requirement, and are not specifically limited herein. In addition, a placement position of the switch component may be determined in a plurality of manners. The following uses the printed antenna shown in
Step 1: Design antennas with a plurality of operating frequencies and whose directivity patterns are single radiation modes.
Step 2: Segment the antennas with single radiation modes by using the loop antenna body as a complete antenna, to obtain a plurality of antenna branches that do not overlap each other.
Step 3: Determine the position of the switch component based on the antenna branches. Specifically, the loop antenna body may be divided into the branch A, the branch B, the branch C, and the branch D by performing step 1 and step 2. In this case, a position between every two adjacent branches is a position at which each switch component is disposed. In addition, a switch component may also be disposed between the branch D and the ground point.
It should be noted that an operating frequency band of the printed antenna covers an operating frequency band (including 2.4 GHz and 5 GHz) of a wireless local area network (WLAN) standard and an operating frequency band (including 1.6 GHz to 2.2 GHz and 2.3 GHz to 2.7 GHz) of a long term evolution (LTE) standard. In addition, the printed antenna provided in this disclosure is not limited to a WLAN frequency band and an LTE frequency band. A size of the printed antenna, a quantity of antenna branches, and a division manner may be adjusted to meet more application requirements.
In the embodiments of this disclosure, the loop antenna body includes a plurality of loop antenna branches, and the switch component is disposed between every two adjacent loop antenna branches. Each switch component may connect or disconnect two adjacent loop antenna branches. The operating frequency of the loop antenna changes in two different statuses in which the switch component is turned on or off. Therefore, a plurality of operating frequencies and directivity patterns may be covered by adjusting turn-on or turn-off of each switch component, thereby expanding the operating frequency and the directivity pattern coverage mode that can be selected by the antenna.
It should be noted that the foregoing embodiments are merely intended to describe the technical solutions of this disclosure other than to limit this disclosure. Although this disclosure is described in detail with reference to the foregoing embodiments, persons of ordinary skill in the art should understand that they may still make modifications to the technical solutions described in the foregoing embodiments or make equivalent replacements to some technical features thereof, without departing from the spirit and scope of the technical solutions of the embodiments of this disclosure.
Number | Date | Country | Kind |
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201911345171.7 | Dec 2019 | CN | national |
This application is a continuation of International Application No. PCT/CN2020/116438, filed on Sep. 21, 2020, which claims priority to Chinese Patent Application No. 201911345171.7, filed on Dec. 23, 2019. The disclosures of the aforementioned applications are hereby incorporated by reference in their entireties.
Number | Date | Country | |
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Parent | PCT/CN2020/116438 | Sep 2020 | US |
Child | 17846215 | US |