This application relates to the field of communications technologies, and in particular, to a feeding device.
With continuous upgrading of mobile communications systems, multi-beam, miniaturization, and the like become main factors of modern antenna design. A multibeam communications network is a main technology that implements a multibeam antenna using spatial selectivity. Advantages such as spatial multiplexing, interference mitigation, and the like may be brought by using a spatial selectivity method. Currently, in the multibeam communications network, a Rotman lens is a mainly used feeding device. The Rotman lens has features such as a high bandwidth, being capable of being designed in a plane, and irrelevance between a beam direction and frequency. However, the Rotman lens has a relatively high insertion loss.
Embodiments of this application provide a feeding device, to reduce an insertion loss of the feeding device.
According to a first aspect, an embodiment of this application provides a feeding device, where the feeding device includes a body and at least one first port, the body includes at least one first contour port, and each of the at least one first contour port corresponds to one of the at least one first port; and the first contour port includes at least two sub-ports, and the at least two sub-ports of the first contour port are connected, by using at least one power splitter, to the first port corresponding to the first contour port.
In the foregoing implementation solution, the first contour port is divided into several sub-ports, where a feeding width of each sub-port is less than an original feeding width of the first contour port, and the first port and the several sub-ports are connected by using the at least one power splitter. Therefore, returned energy is less, and signals are more uniformly fed into the body, so that miniaturization of the body and a low insertion loss are achieved.
In a specific implementation solution, the feeding device further includes at least one second port, the body further includes at least one second contour port, and each of the at least one second contour port corresponds to one of the at least one second port; and the second contour port and the second port corresponding to the second contour port are connected by using a stepped impedance transformation structure. Therefore, energy returning to the body is less, and the insertion loss of the body is reduced.
In a specific implementation solution, a length a of each step of impedance structure in the stepped impedance transformation structure in a direction in which the second contour port points to the second port meets: the length a is a quarter of a wavelength corresponding to a central frequency of an operating frequency band of the feeding device.
In a specific implementation solution, the stepped impedance transformation structure is a microstrip stepped impedance transformation structure, a strip line stepped impedance transformation structure, or a coaxial line stepped impedance transformation structure, such as a stepped impedance transformation structure that is produced using a microstrip.
In a specific implementation solution, a redundant port is further disposed on the body, where the redundant port is disposed between two first contour ports; or the redundant port is disposed between the first contour port and the second contour port. Isolation between the contour ports is increased using the redundant port.
In a specific implementation solution, the power splitter is a microstrip power splitter, a strip line power splitter, or a coaxial line power splitter.
In a specific implementation solution, the feeding device further includes at least one third port, the body further includes at least one third contour port, and each of the at least one third contour port corresponds to one of the at least one third port; and the third contour port and the third port corresponding to the third contour port are connected by using a horn-shaped impedance converter.
The following describes the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application.
In this application, the term “a plurality of” refers to two or more, and other quantifiers are similar. The term “and/or” describes an association relationship between associated objects and represents that three relationships may exist. For example, A and/or B may represent the following three cases: only A exists, both A and B exist, and only B exists. The character “/” generally indicates an “or” relationship between the associated objects.
An embodiment of this application provides a feeding device, and the feeding device includes a body and at least one port. Optionally, the port may be an input port and/or output port of the feeding device. Correspondingly, a contour port corresponding to each port is disposed on the body. In descriptions of this application, the contour port may be a specific port, or may be a feeding section. For example, the contour port may be an arc-shaped section on the body, or the contour port may be an irregular feeding section on the body. This is not limited herein. Each port and the contour port corresponding to the port are connected. In a possible implementation, each port and the contour port corresponding to the port are connected by using a component.
In this embodiment of this application, a contour port of the feeding device may include at least two sub-ports, and the at least two sub-ports are connected to a port using at least one power splitter. In descriptions of this application, the sub-port may be a specific port, or may be a feeding section. This is not limited herein. The feeding device in this embodiment of this application may effectively reduce an occupied area of the feeding device. Therefore, miniaturization of the feeding device is achieved. Optionally, the at least one power splitter is connected in a cascading manner, such as two-level cascading and three-level cascading. This application constitutes no limitation on a quantity of the power splitters and a quantity of cascaded levels of the power splitters. Furthermore, the feeding device in this embodiment of this application may enable returning energy to be less, and signals to be more uniformly fed into the body.
To accurately describe various ports corresponding to the contour ports, in the embodiments of this application, a first port and a second port are used as an example for description. The first port may be an input port or an output port of the feeding device. When there is a plurality of first ports, some first ports may serve as the input ports of the feeding device, and some first ports may serve as the output ports of the feeding device. Specific effects of the first port depend on a scenario in which the feeding device is used. The second port may be an output port or an input port of the feeding device. When there is a plurality of second ports, some second ports may serve as the input ports of the feeding device, and some second ports may serve as the output ports of the feeding device. In a possible implementation, if the body has both the first port and the second port, when the first port serves as the input port of the feeding device, the second port serves as the output port of the feeding device; or when the first port serves as the output port of the feeding device, the second port serves as the input port of the feeding device. The two ports may be used based on a practical requirement. In a possible implementation, when there is a plurality of first ports and second ports, some first ports and second ports may serve as the input ports of the feeding device, and some first ports and second ports may serve as the output ports of the feeding device.
In a possible implementation, the feeding device is a Rotman lens.
For ease of understanding the feeding device provided in this embodiment, the following uses a feeding device shown in
For the feeding device shown in
In the feeding device shown in
Specific implementations of the first contour ports 11 (namely, the contour input port) and the second contour ports 12 (namely, the contour output port) shown in
In a possible implementation, when signals are propagated, the feeding device divides each first contour port 11 on the body 10 into at least two sub-ports 14, that is, each first contour port 11 includes at least two sub-ports 14. When there are two sub-ports 14, the two sub-ports 14 are connected to the first port 20 by using a power splitter 40. When there is a plurality of sub-ports, the plurality of sub-ports 14 are connected, using the cascaded power splitter 40, to the first port 20 corresponding to the first contour port 11. In a structure shown in
It should be understood that
The power splitter 40 may be a microstrip power splitter, a strip line power splitter, or a coaxial line power splitter. A microstrip power splitter is used in this embodiment.
In the foregoing embodiment, several power splitters 40 are used to feed signals into the contour input port in an equal phase. By using a connection manner in which the power splitter 40 feeds power, returning energy is less, and signals are more uniformly fed into the body. In addition, using the connection manner in which the cascaded power splitter 40 is used, an occupied area of the feeding device is effectively reduced. Therefore, miniaturization of the feeding device is achieved.
To implement feeding device broadband, a Chebyshev impedance transformation is used on each power splitter. The Chebyshev impedance transformation is a relatively great broadband impedance transformation in which a return loss is little. As shown in
In a possible implementation, to further improve performance of the feeding device provided in this embodiment, each second contour port 12 and the second port 30 corresponding to the second contour port 12 are connected using the stepped impedance transformation structure 50, that is, the second port 30 is connected to the second contour port 12 by using the stepped impedance transformation structure. The stepped impedance transformation structure 50 is an impedance transformation structure which has gradually increased impedances in a direction in which the second contour port 12 points to the second port 30. The stepped impedance transformation structure 50 is a microstrip stepped impedance transformation structure, a strip line stepped impedance transformation structure, or a coaxial line stepped impedance transformation structure. With reference to
In the foregoing embodiment, by using the stepped impedance transformation structure 50 between the second port 30 and the second contour port 12, energy that returns to a contour is less. Therefore, the return loss of the output port is reduced.
In a possible implementation, as shown in
In a possible implementation, the redundant port 13 may further be disposed between the first contour port 11 and the second contour port 12. The redundant port 13 may reduce unnecessary electromagnetic reflection on the feeding device, and a signal transmission disorder may be caused when excessively much electromagnetic reflection is reduced. A quantity of the redundant ports 13 that are disposed between the first contour port 11 and the second contour port 12 may be selected based on a requirement, such as one or two or three redundant ports 13. As shown in
For ease of understanding the feeding device provided in this embodiment, the following describes an electromagnetic model of the feeding device provided in an embodiment of this application.
The electromagnetic model of the feeding device shown in
It can be learned from the foregoing embodiment that the feeding device provided in this application effectively reduces an occupied space area and the insertion loss.
It should be understood that, in the foregoing embodiments, although the first port serves as the input port of the feeding device, and the second port serves as the output port of the feeding device, the first port may also serve as the output port of the feeding device and the second port may also serve as the input port of the feeding device, or some first ports serve as the input ports of the feeding device and some first ports serve as the output ports of the feeding device; or some second ports serve as the input ports of the feeding device and some second ports serve as the output ports of the feeding device. Principles thereof are similar to the foregoing specific embodiments, and details are not described herein again.
In a possible implementation, the feeding device provided in this embodiment of this application further includes at least one third port, the body further includes at least one third contour port, and each of the at least one third contour port corresponds to one of the at least one third port; and the third contour port and the third port corresponding to the third contour port are connected by using a horn-shaped impedance converter. Specifically, in a first case, the feeding device includes the first port and the third port, and correspondingly, the first contour port and the third contour port are disposed on the body. In a second case, the feeding device includes the first port, the second port, and the third port, and correspondingly, the first contour port, the second contour port, and the third contour port are disposed on the body.
First, for the first case, as shown in
It should be understood that, in a structure shown in
For the second case, as shown in
The first port 60 serves as an input port of the feeding device, the second port 90 serves as an output port of the feeding device, and the third port 70 may serve as the input port of the feeding device or the output port of the feeding device. Correspondingly, the first contour port serves as a contour input port, the second contour port serves as a contour output port, and the third contour port may serve as the contour input port or the contour output port. The first port 60 is connected to the first contour port by using a plurality of power splitters, and the second port 90 is connected to the third contour port by using a stepped impedance transformation structure 50. For descriptions of the connection manner and effects thereof, refer to the descriptions of the input port and the output port of the feeding device shown in
A redundant port may also be disposed on the feeding device. The redundant port may be disposed between any two contour input ports (the first contour port and the first contour port, or the first contour port and the third contour port); or may be disposed between the contour input port (the first contour port or the third contour port) and the contour output port (the second contour port or the third contour port). Effects of the redundant port are the same as the effects of the redundant port described in the foregoing embodiments, and details are not described herein again.
It can be learned from the foregoing descriptions that the input port is connected to sub-ports of the contour input port by using the power splitter 40, an occupied area of the feeding device may be effectively reduced, and an insertion loss may be effectively reduced.
It should be understood that, in a structure as shown in
Obviously, a person skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of this application. This application is intended to cover these modifications and variations provided that they fall within the scope of protection defined by the following claims and their equivalent technologies.
This application is a continuation of International Application No. PCT/CN2017/090037, filed on Jun. 26, 2017, the disclosure of which is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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Parent | PCT/CN2017/090037 | Jun 2017 | US |
Child | 16726455 | US |