Patent Description:
A wireless local area network usually includes a plurality of wireless access points (APs) that operate at a same frequency. A signal coverage area of a single wireless access point needs to be adjusted correspondingly based on a different use scenario requirement. When adjacent wireless access points are close to each other, the signal coverage area of the single wireless access point needs to be small, to avoid co-channel interference. When adjacent wireless access points are far away from each other, the signal coverage area of the single wireless access point needs to be large, to avoid a signal coverage hole.

The wireless access point may implement switching between beams at different azimuths by using a reconfigurable antenna. However, a beam at a pitch angle may be usually implemented by perform switching between two or more antennas by using a radio frequency switch. The antennas have different maximum gain directions. In such an adjustment manner, there is a high insertion loss, overall antenna performance decreases, and an antenna size is increased. <CIT> discloses an antenna system including a system ground plane, a first antenna array, and a second antenna array. The first antenna array includes a first antenna element, a second antenna element, a third antenna element, and a fourth antenna element. The second antenna array includes a fifth antenna element, a sixth antenna element, a seventh antenna element, and an eighth antenna element. The second antenna array is disposed between the first antenna array and the system ground plane. The first antenna array has a first polarization direction. The second antenna array has a second polarization direction. The first polarization direction and the second polarization direction are orthogonal to each other. <CIT> discloses a switchable antenna applied to wireless communication. The switchable antenna controls the state of a reflector corresponding to each antenna unit to obtain an expected radiation direction diagram, thereby realizing self adaption to the wireless environment and providing efficient and reliable communication link connection to two transmitting and receiving devices. Another aspect of the invention describes a switch (for example, a diode) used for connecting the two reflectors. Electronic control of the on-off states of the diode is carried out so that the corresponding two reflectors are electrically connected or disconnected.

This application provides a reconfigurable antenna, to implement a function of switching beams at a pitch angle when there is a small insertion loss. This application further relates to a network device including the reconfigurable antenna. Specific technical solutions are as follows:.

According to a first aspect, this application provides a reconfigurable antenna, including a bottom plate, a vertically polarized high-density antenna, wherein the bottom plate is disposed in the polarization direction of the vertically polarized high-density antenna, and a controllable reflector. The controllable reflector is located between the bottom plate and the vertically polarized high-density antenna, and a projection of the controllable reflector on the bottom plate is at a center of a projection of the vertically polarized high-density antenna on the bottom plate; and the controllable reflector includes a switch, and the switch is configured to enable the controllable reflector to be in an operating state or an off state
wherein the controllable reflector is further provided with an inductor structure, the inductor structure and the switch are connected in parallel, the inductor structure and the switch form a resonator, and a resonance frequency of the resonator falls within the operating frequency band of the vertically polarized high-density antenna.

In this application, the reconfigurable antenna reflects a signal of the vertically polarized high-density antenna by using the bottom plate, to improve overall performance of the antenna. The controllable reflector disposed between the bottom plate and the vertically polarized high-density antenna and located at a central location of the vertically polarized high-density antenna can reflect a beam of the vertically polarized high-density antenna outwards. When the switch of the controllable reflector is opened, the controllable reflector is in the off state. In this case, a pitch angle of the vertically polarized high-density antenna is narrow, and a signal coverage area is small, so that a high-density characteristic can be implemented. However, when the switch of the controllable reflector is closed, the controllable reflector is in the operating state. In this case, because the controllable reflector reflects a beam outwards, the pitch angle of the vertically polarized high-density antenna is widened, and the signal coverage area is correspondingly extended. Compared with a form of switching an antenna by using a radio frequency switch, in a process of adjusting a pitch angle of the reconfigurable antenna in this application, there is a smaller insertion loss, and a size of the reconfigurable antenna is also controlled.

In a possible implementation, the controllable reflector includes a part parallel to a polarization direction of the vertically polarized high-density antenna, a distance D1 between the controllable reflector and the vertically polarized high-density antenna meets a condition: D1 ≤ <NUM>/4λ, and λ is a wavelength corresponding to an operating frequency band of the vertically polarized high-density antenna.

In this implementation, the part that is of the controllable reflector and that is parallel to the polarization direction of the vertically polarized high-density antenna may reflect more beams in the polarization direction. However, the distance between the controllable reflector and the vertically polarized high-density antenna is set, to control a phase difference between the controllable reflector and the vertically polarized high-density antenna, and improve reflection efficiency of the controllable reflector.

In a possible implementation, in the polarization direction of the vertically polarized high-density antenna, the controllable reflector includes a first end close to the bottom plate, and the first end is electrically connected to the bottom plate.

In this implementation, the controllable reflector and the bottom plate are electrically connected, to extend a distance in which the controllable reflector performs an action on a beam, and further improve reflection efficiency of the controllable reflector.

In a possible implementation, the controllable reflector further includes a second end opposite the first end, and the switch is located closer to the first end than the second end.

In this implementation, the switch is disposed on a side close to the bottom plate, to reduce impact that is on a beam and that exists when the controllable reflector is in the off state, and improve a difference in reflection efficiency of the controllable reflector between the off state and the operating state.

In a possible implementation, a length of the controllable reflector in the polarization direction of the vertically polarized high-density antenna is a first length L1, and the first length L1 meets a condition: <NUM>/4λ ≤ L1 ≤ λ.

In this implementation, the length of the controllable reflector is controlled, to ensure a distance in which the controllable reflector performs an action on a beam, and improve reflection efficiency of the controllable reflector.

According to the invention, the controllable reflector is further provided with an inductor structure, the inductor structure and the switch are connected in parallel, the inductor structure and the switch form a resonator, and a resonance frequency of the resonator falls within the operating frequency band of the vertically polarized high-density antenna.

Thus, the inductor structure is disposed, to form the resonator in an operating frequency band of the switch, form large impedance when the switch is opened, and improve an isolation degree existing when the switch in an opened state.

In a possible implementation, there is one controllable reflector; or there are a plurality of controllable reflectors, and the plurality of controllable reflectors are evenly distributed in a circle.

In this implementation, when there is one controllable reflector, the controllable reflector may be located at a central location of the vertically polarized high-density antenna, so that a radiation pattern of the reconfigurable antenna in this application is more evenly distributed; or when there are a plurality of controllable reflectors, the plurality of controllable reflectors are evenly distributed, to increase a range in which the controllable reflector performs an action on a beam, and further increase the pitch angle of the reconfigurable antenna.

In a possible implementation, when the controllable reflector is in the off state, an angle corresponding to a maximum gain of a pitch angle of the reconfigurable antenna is <NUM> degrees; or when the controllable reflector is in the operating state, an angle corresponding to a maximum gain of a pitch angle of the reconfigurable antenna is <NUM> degrees.

In this implementation, when the angle corresponding to the maximum gain of the pitch angle of the reconfigurable antenna is controlled to be <NUM> degrees, the reconfigurable antenna in this application may operate in a high density mode. When the angle corresponding to the maximum gain of the pitch angle of the reconfigurable antenna is controlled to be <NUM> degrees, the reconfigurable antenna in this application may operate in an omnidirectional mode or a directional mode.

In a possible implementation, when the vertically polarized high-density antenna is in a directional mode, a maximum gain that is of the reconfigurable antenna and that exists when the controllable reflector is in the operating state is <NUM> decibel to <NUM> decibels greater than a maximum gain that is of the reconfigurable antenna and that exists when the controllable reflector is in the off state.

In this implementation, the vertically polarized high-density antenna may be set to be in the directional mode, to implement a larger signal coverage area in a preset direction. In addition, under the action of the controllable reflector, the maximum gain of the reconfigurable antenna in this application can be further improved in the directional mode, to improve antenna performance of the reconfigurable antenna.

In a possible implementation, the vertically polarized high-density antenna includes N dipoles and a feeding part, N is an integer greater than or equal to <NUM>, each dipole is connected to the feeding part, and the dipoles are distributed in a circle.

In this implementation, the N dipoles distributed in the circle form a radiation element of the vertically polarized high-density antenna, and signals are fed into the dipoles respectively through the feeding part, to form a low side lobe characteristic in the polarization direction of the vertically polarized high-density antenna, and suppress co-channel interference.

In a possible implementation, the vertically polarized high-density antenna is a dipole antenna, each dipole includes a pair of an upper dipole and a lower dipole, and the feeding part separately feeds each upper dipole and feeds each lower dipole.

In a possible implementation, the vertically polarized high-density antenna is a monopole antenna, the vertically polarized high-density antenna is further provided with a grounding part, and the grounding part is located between each dipole and the bottom plate.

In the foregoing two implementations, the vertically polarized high-density antenna has different constitution forms, and the low side lobe characteristic in the polarization direction can be implemented.

In a possible implementation, a length direction of each dipole points to a center of the vertically polarized high-density antenna, and a length of each dipole in the direction meets a condition: <NUM>/4λ ≤ L2 ≤ <NUM>/4λ.

In this implementation, the length direction of each dipole points to the center of the vertically polarized high-density antenna, so that a radiation pattern of the vertically polarized high-density antenna can be more even. However, the length of each dipole is limited, to improve radiation efficiency of each dipole.

In a possible implementation, the feeding part is located at a center of each dipole.

In this implementation, a location of the feeding part is set, to reduce an insertion loss of the vertically polarized high-density antenna.

In a possible implementation, the feeding part includes a power splitter, an impedance conversion line, and an ohm transmission line.

In this implementation, the feeding part feeds a signal through the power splitter, and feeds the signal into each dipole through the impedance conversion line and the ohm transmission line, to implement a feeding function.

In a possible implementation, the vertically polarized high-density antenna further includes a circuit board, and each dipole and the feeding part are disposed on an outer surface of the circuit board.

In a possible implementation, the vertically polarized high-density antenna is further provided with a plurality of azimuth reflectors, each azimuth reflector is also distributed in a circle, a length direction of each azimuth reflector is parallel to the polarization direction, and there is a maximum of one azimuth reflector between two adjacent dipoles.

The azimuth reflector is disposed, so that the radiation pattern of the vertically polarized high-density antenna is even, to improve a radiation capability of the vertically polarized high-density antenna in a horizontal direction.

In a possible implementation, each azimuth reflector is also provided with a switch.

In this implementation, the switch of the azimuth reflector is controlled, to adjust a horizontal radiation angle of the vertically polarized high-density antenna, so that the vertically polarized high-density antenna is switched between the directional mode and the omnidirectional mode.

In a possible implementation, each switch of each azimuth reflector is located at a central location of the azimuth reflector.

In this implementation, a location of the switch on the azimuth reflector is set, to reduce impact that is on a beam and that exists when the azimuth reflector is in an off state, and improve a reflection efficiency difference of the azimuth reflector between the off state and an operating state.

According to a second aspect, this application provides a network device, including a radio frequency circuit, a control circuit, and the reconfigurable antenna according to the first aspect of this application. The radio frequency circuit is electrically connected to the reconfigurable antenna, and a switch is controlled by the control circuit.

Technical effects achieved in the second aspect are similar to technical effects achieved by the corresponding technical means in the first aspect, and details are not described herein again.

<FIG> is a diagram of an application scenario of a network device according to an embodiment of this application. As shown in <FIG>, the scenario includes a controller <NUM>, an access point (access point, AP) <NUM>, and a plurality of terminals <NUM>. The controller <NUM> may manage and configure the access point <NUM>, and forward user data. The access point <NUM> is configured to provide a wireless access service for a plurality of connected terminals <NUM>. The network device provided in this application may be a base station, a router, a switch, or the like, and works as the access point <NUM>. The plurality of terminals <NUM> may be products such as a mobile phone, a computer, and a smart home appliance. In addition, only three terminals are used as an example for description in <FIG>, and do not constitute a limitation on a quantity of terminals in the application scenario provided in this embodiment of this application.

<FIG> is a diagram of an application scenario in which a plurality of network devices are deployed according to this application. A controller <NUM> may be configured to: centrally manage and configure a plurality of access points <NUM>, and forward user data. The plurality of access points <NUM> are usually disposed at a height of <NUM> meters to <NUM> meters (m). A radius of a coverage cell may be different based on a use requirement, and may be set to be less than <NUM> or fall within a range from <NUM> to <NUM>, or may even be greater than <NUM>.

For a use scenario requirement, a communication capacity and a quantity of channels are usually considered. When there is a large quantity of users per unit area, to ensure the communication capacity, it may be set that the access point <NUM> performs signal coverage in a large-angle omnidirectional mode (for example, a coverage radius of the access point <NUM> falls within the range from <NUM> and <NUM>). However, there is a limited quantity of channels of the single access point <NUM>. In this case, a distance between access points <NUM> may be set to be reduced, and signal coverage is performed in a small-angle high density mode (for example, a coverage radius of the access point <NUM> is less than <NUM>). However, in a scenario in which there is a small quantity of users per unit area and there is a large cell area, a distance between access points <NUM> may alternatively be set to be large, and signal coverage is performed in a super-large-angle directional mode (for example, a coverage radius of the access point <NUM> is greater than <NUM>).

<FIG> is a schematic diagram of a structure of a network device according to an embodiment of this application. For example, the access point <NUM> in <FIG> may be implemented by using the network device shown in <FIG>. Refer to <FIG>. The network device includes a baseband circuit <NUM>, a radio frequency circuit <NUM>, a control circuit <NUM>, and a reconfigurable antenna <NUM>.

The baseband circuit <NUM> is configured to process a received radio signal or a to-be-sent radio signal.

The reconfigurable antenna <NUM> is a reconfigurable antenna provided in this application. The reconfigurable antenna <NUM> includes a vertically polarized high-density antenna <NUM> and a switch <NUM>. For descriptions of the vertically polarized high-density antenna <NUM> and the switch <NUM>, refer to related descriptions in subsequent embodiments.

The radio frequency circuit <NUM> is connected between the vertically polarized high-density antenna <NUM> of the reconfigurable antenna <NUM> and the baseband circuit <NUM>, and is configured to cooperate with the reconfigurable antenna <NUM> to receive and send a radio signal.

The control circuit <NUM> is electrically connected to the switch <NUM> of the reconfigurable antenna <NUM>, and is configured to control an operating mode of the reconfigurable antenna <NUM>, so that a radiation angle of the reconfigurable antenna <NUM> can be switched, to change a signal coverage area, and adapt to different use scenario requirements. The control circuit <NUM> may be implemented by using a complex programmable logical device (CPLD), or in a general purpose input/output (GPIO) manner.

The following describes the reconfigurable antenna <NUM> provided in this embodiment of this application.

<FIG> is a schematic diagram of a structure of a reconfigurable antenna <NUM> according to an embodiment of this application. As shown in <FIG>, the reconfigurable antenna <NUM> may include a bottom plate <NUM>, a vertically polarized high-density antenna <NUM>, and a controllable reflector <NUM>. The vertically polarized high-density antenna <NUM> serves as a radiation body of the reconfigurable antenna <NUM>, and is configured to separately radiate to two opposite sides in a polarization direction of the vertically polarized high-density antenna <NUM>. The bottom plate <NUM> is conductive, and is disposed in the polarization direction of the vertically polarized high-density antenna <NUM>. The bottom plate <NUM> and the vertically polarized high-density antenna <NUM> are spaced from each other. The bottom plate <NUM> may reflect a signal beam emitted by the vertically polarized high-density antenna <NUM>, so that after a signal beam emitted by the vertically polarized high-density antenna <NUM> toward one side is reflected, the signal beam converges with a signal beam on the other side, and propagates toward a same side of the vertically polarized high-density antenna <NUM>. Usually, a direction of the same side is a downward propagation direction of a network device. In other words, the signal beam emitted by the vertically polarized high-density antenna <NUM> propagates toward the same side in the polarization direction of the vertically polarized high-density antenna <NUM> under a reflection action of the bottom plate <NUM>, to improve signal strength and achieve high density.

It can be understood that the vertically polarized high-density antenna <NUM> is a linearly polarized antenna, and the polarization direction of the vertically polarized high-density antenna <NUM> is a linear direction. In addition, because the bottom plate <NUM> is disposed on one side in the polarization direction of the vertically polarized high-density antenna <NUM> and spaced from the vertically polarized high-density antenna <NUM>, a pitch angle of the vertically polarized high-density antenna <NUM> is small, and an azimuth coverage area is also small, to achieve vertical polarization. In the reconfigurable antenna <NUM> in this application, the vertically polarized high-density antenna <NUM> may implement a high density mode of the reconfigurable antenna <NUM>, to implement small-range large-capacity communication.

The controllable reflector <NUM> is located between the bottom plate <NUM> and the vertically polarized high-density antenna <NUM>. In the schematic diagram of <FIG>, there is one controllable reflector <NUM>, and a length direction of the controllable reflector <NUM> is also disposed in the polarization direction of the vertically polarized high-density antenna <NUM>. In other words, an entirety of the controllable reflector <NUM> is disposed parallel to the polarization direction of the vertically polarized high-density antenna <NUM>. The controllable reflector <NUM> includes a switch <NUM>, and the switch <NUM> is configured to implement switching of the controllable reflector <NUM> between an off state and an operating state. It can be understood that, as described above, a control circuit <NUM> controls an operating mode of the reconfigurable antenna <NUM>. In other words, the operating mode of the reconfigurable antenna <NUM> may be implemented by that the control circuit <NUM> electrically connecting and controlling the switch <NUM>.

Refer to <FIG>. In the schematic diagram of <FIG>, a projection <NUM>' of the vertically polarized high-density antenna <NUM> on the bottom plate <NUM> in the polarization direction of the vertically polarized high-density antenna <NUM> is in an annular shape (a case in which a feeding network is located at a phase center is not considered), and has an inner circle and an outer circle. A projection of the controllable reflector <NUM> on the bottom plate <NUM> in the polarization direction is located at a center of the projection <NUM>' in the annular shape. In some embodiments, the controllable reflector <NUM> may alternatively properly offset relative to the center of the annular shape, but in this case, the reflector <NUM> still falls within the inner circle of the projection <NUM>' in the annular shape. In some other embodiments, the projection <NUM>' of the vertically polarized high-density antenna <NUM> on the bottom plate <NUM> in the polarization direction of the vertically polarized high-density antenna <NUM> may alternatively be in an elliptical annular shape or approximately in any hollow shape such as a shape of two concentric squares. In this case, the controllable reflector <NUM> may be located at a center of the hollow shape or offset relative to a central location, and remain within an inner circle of the hollow shape.

Under the action of the switch <NUM>, the controllable reflector <NUM> can be switched between the off state and the operating state. When the switch <NUM> is opened, the controllable reflector <NUM> is in the off state. In this case, the controllable reflector <NUM> does not affect a beam of the reconfigurable antenna <NUM>, and a signal coverage area of the reconfigurable antenna <NUM> is represented as a coverage area of the vertically polarized high-density antenna <NUM>. As mentioned above, the coverage area of the vertically polarized high-density antenna <NUM> is small. In this case, the operating state of the reconfigurable antenna <NUM> is in a high density mode.

When the switch <NUM> is closed, the reflector <NUM> is in the operating state. In this case, the controllable reflector <NUM> reflects the beam emitted by the vertically polarized high-density antenna <NUM>. Specifically, because the controllable reflector <NUM> is located at a central location of the vertically polarized high-density antenna <NUM>, the controllable reflector <NUM> may reflect the signal beam emitted by the vertically polarized high-density antenna <NUM> outwards in a direction parallel to the bottom plate <NUM>. To be specific, in a horizontal direction of the vertically polarized high-density antenna <NUM>, the controllable reflector <NUM> at the central location reflects the signal beam, so that a pitch angle of the vertically polarized high-density antenna <NUM> is increased, to further extend the coverage area of the vertically polarized high-density antenna <NUM>. In other words, an action radius of the vertically polarized high-density antenna <NUM> is increased. In this case, the operating state of the reconfigurable antenna <NUM> may be the foregoing omnidirectional mode or directional mode, and is specifically determined based on a shape of a radiation pattern of the vertically polarized high-density antenna <NUM>.

<FIG> and <FIG> respectively show pitch angle simulation results of a reconfigurable antenna <NUM> that exist when a controllable reflector <NUM> is in different states according to this application. <FIG> shows a simulation result existing when the controllable reflector <NUM> is in the off state. It can be learned that, under the action of the vertically polarized high-density antenna <NUM>, an angle corresponding to a maximum gain of a pitch angle of the reconfigurable antenna <NUM> in this application is <NUM> degrees. In other words, when the reconfigurable antenna <NUM> in this application operates in the high density mode, a pitch angle of the reconfigurable antenna <NUM> is approximately <NUM> degrees. <FIG> shows a simulation result existing when the controllable reflector <NUM> is in the operating state. It can be learned that, under the action of the controllable reflector <NUM>, the angle corresponding to a maximum gain of a pitch angle of the reconfigurable antenna <NUM> in this application is extended to <NUM> degrees. In other words, when the reconfigurable antenna <NUM> in this application operates in the omnidirectional mode or the directional mode, the pitch angle of the reconfigurable antenna <NUM> is approximately <NUM> degrees.

With reference to the schematic diagram of <FIG>, a height of <NUM> is still used for illustration. In a possible implementation, when the vertically polarized high-density antenna <NUM> in the reconfigurable antenna <NUM> in this application operates in the high density mode, the signal coverage area of the reconfigurable antenna <NUM> is shown by dotted lines in <FIG>, and signal coverage may be implemented in a range with a radius of <NUM>. However, when the vertically polarized high-density antenna <NUM> in the reconfigurable antenna <NUM> in this application operates in the omnidirectional mode, the signal coverage area of the reconfigurable antenna <NUM> is shown by a straight line in <FIG>, and signal coverage may be implemented in a range with a radius of <NUM>.

It can be learned that, under the action of the controllable reflector <NUM>, the pitch angle of the reconfigurable antenna <NUM> in this application may be adjusted in a large range. In addition, compared with a pitch angle adjustment manner in which a plurality of antennas are combined and a radio frequency switch chooses to perform switching, in this application, an insertion loss of the reconfigurable antenna <NUM> is smaller, and antenna operating efficiency is improved. In addition, the pitch angle of the reconfigurable antenna <NUM> in this application can be adjusted in a large range only by disposing the vertically polarized high-density antenna <NUM>. Compared with a structure in which radio frequency combination is performed on a plurality of antennas, the reconfigurable antenna <NUM> in this application has a smaller overall size, and further facilitates miniaturization and cost control of the network device in this application.

<FIG> is a side view of an embodiment of a reconfigurable antenna <NUM> in this application. In this embodiment, the controllable reflector <NUM> is in a strip shape, and is located at a center of the vertically polarized high-density antenna <NUM>, and the length direction of the controllable reflector <NUM> is disposed parallel to the polarization direction of the vertically polarized high-density antenna <NUM>. Because the signal beams emitted by the vertically polarized high-density antenna <NUM> also propagate approximately parallel to the polarization direction of the vertically polarized high-density antenna <NUM>, the controllable reflector <NUM> is disposed parallel to the polarization direction to reflect more beams. However, when the controllable reflector <NUM> is disposed at the central location of the vertically polarized high-density antenna <NUM>, reflection effects of the controllable reflector <NUM> on signal beams in a range of <NUM> degrees in the horizontal direction tend to be consistent, so that a radiation pattern of the reconfigurable antenna <NUM> in this application is distributed more evenly.

In an embodiment, it is further set that the controllable reflector <NUM> has a first length L1 in the polarization direction, and that the first length L1 meets a condition: <NUM>/4λ ≤ L1 ≤ λ. Further, a distance in which the controllable reflector <NUM> performs a reflection action on a signal beam is ensured, and reflection efficiency of the controllable reflector <NUM> is improved.

In this embodiment, the controllable reflector <NUM> includes a first end <NUM> and a second end <NUM> that are opposite in the length direction of the controllable reflector <NUM>, the first end <NUM> is located on a side close to the bottom plate <NUM>, and the second end <NUM> is located on a side close to the vertically polarized high-density antenna <NUM>. The second end <NUM> of the controllable reflector <NUM> and the vertically polarized high-density antenna <NUM> are disposed by being spaced from each other, there is a first spacing distance D1 between second end <NUM> and the vertically polarized high-density antenna <NUM>, the first spacing distance D1 further meets the following condition: D1 ≤ <NUM>/4λ, and λ is a wavelength corresponding to an operating frequency band of the vertically polarized high-density antenna <NUM>. Therefore, a phase difference may be formed between the controllable reflector <NUM> and the vertically polarized high-density antenna <NUM>, to improve reflection efficiency of the controllable reflector <NUM>.

On one side of the first end <NUM>, the first end <NUM> is in contact with the bottom plate <NUM> in a fixed manner. In other words, the first end <NUM> and the bottom plate <NUM> are electrically connected. In this case, the bottom plate <NUM> is used as a reflection surface of the vertically polarized high-density antenna <NUM>, and the distance in which the controllable reflector <NUM> performs an action on the signal beam is extended through an electrical connection between the bottom plate <NUM> and the controllable reflector <NUM>, to further improve efficiency in reflection performed by the controllable reflector <NUM> on the signal beam, and further increase the pitch angle of the reconfigurable antenna <NUM>.

The switch <NUM> is located between the first end <NUM> and the second end <NUM>, and the switch <NUM> is located at a location closer to the first end <NUM> than the second end <NUM>. In other words, the switch <NUM> is located on the side close to the bottom plate <NUM>, to reduce impact that is on the signal beam and that exists when the controllable reflector <NUM> is in the off state, provide a larger difference in reflection efficiency of the controllable reflector <NUM> between the operating state and the off state, and provide a larger pitch angle change amount of the reconfigurable antenna <NUM> in this application.

According to the invention, as shown in <FIG>, the controllable reflector <NUM> is further provided with an inductor structure <NUM>. The inductor structure <NUM> and the switch <NUM> are connected in parallel, and form a resonator. A resonance frequency of the resonator falls within the operating frequency band of the vertically polarized high-density antenna <NUM>. The resonator may form large impedance when the switch <NUM> is opened, to improve an isolation degree that is of the switch <NUM> and that exists when the switch <NUM> is in an opened state.

<FIG> shows a structure of another embodiment of a reconfigurable antenna <NUM> in this application. In this embodiment, there are four controllable reflectors <NUM>, and the four controllable reflectors <NUM> are evenly distributed in a circle, and are all separately disposed by offsetting relative to the center of the vertically polarized high-density antenna <NUM>. Referring to <FIG>, each controllable reflector <NUM> includes a first section <NUM> and a second section <NUM> that are disposed parallel to the polarization direction, and a connection section <NUM> connected between the first section <NUM> and the second section <NUM>.

In this embodiment, a plurality of controllable reflectors <NUM> are disposed, to extend an action range of the controllable reflector <NUM> on the signal beam, and further extend the pitch angle of the reconfigurable antenna <NUM>. However, the first section <NUM> and the second section <NUM> are disposed, to ensure the distance in which the controllable reflector <NUM> performs an action on the signal beam, and improves reflection efficiency of the controllable reflector <NUM>.

<FIG> shows a possible structure of a vertically polarized high-density antenna <NUM> according to this application. In the schematic diagram of <FIG>, the vertically polarized high-density antenna <NUM> includes N dipoles <NUM>, a feeding part <NUM>, and a circuit board <NUM>. The circuit board <NUM> may be a printed circuit board (printed circuit board, PCB). A quantity N of dipoles <NUM> is an integer greater than or equal to <NUM>. In <FIG>, that N is <NUM> is used as an example for description, but does not constitute a limitation on the quantity of dipoles <NUM> of the vertically polarized high-density antenna <NUM>. The N dipoles <NUM> and the feeding part <NUM> are all located on the circuit board <NUM>, and the N dipoles <NUM> are all connected to the feeding part <NUM>.

As shown in <FIG>, the N dipoles <NUM> may be distributed and arranged in a circle whose circle center is an antenna phase center. Optionally, the dipoles <NUM> may be arranged in the circle at equal intervals. In other words, an included angle between connection lines between the antenna phase center and every two adjacent dipoles <NUM> is <NUM>/N degrees. A single dipole <NUM> may be constructed as a strip rectangle, and a length direction of the dipole <NUM> may point to a center of an annular shape. In an embodiment, a length of the single dipole <NUM> in this direction meets a condition: <NUM>/4λ ≤ L2 ≤ <NUM>/4λ (refer to <FIG>). A length direction of each dipole <NUM> points to a center of the vertically polarized high-density antenna, so that the radiation pattern of the vertically polarized high-density antenna can be distributed more evenly. However, the length of each dipole <NUM> is limited, to improve radiation efficiency of each dipole <NUM>.

As mentioned above, the N dipoles <NUM> may further enclose an elliptical or rectangular annular shape. The power feeding part <NUM> is located inside the annular shape enclosed by the dipoles <NUM>, so that an insertion loss from the feeding part <NUM> to each dipole <NUM> is smaller. When the quantity N of dipoles <NUM> is an even number, the N dipoles <NUM> may include a plurality of dipole pairs, and two dipoles <NUM> in each dipole pair are centrally symmetrical with respect to the antenna phase center. For example, when N is <NUM>, the included angle between connection lines between the antenna phase center and every two adjacent dipoles <NUM> is <NUM> degrees. The eight dipoles <NUM> may be divided into four dipole pairs, and two dipoles <NUM> in each dipole pair are centrally symmetrical with respect to the antenna phase center. Certainly, the dipoles <NUM> may be arranged at unequal intervals. For example, it is assumed that an included angle between connection lines between the antenna phase center and two adjacent dipoles <NUM> connected to two ends of a same transmission line in the feeding part <NUM> is a first included angle, an included angle between connection lines between the antenna phase center and two adjacent dipoles <NUM> connected to different transmission lines is a second included angle, and the first included angle and the second included angle may be different.

In addition, the N dipoles <NUM> and the feeding part <NUM> may all be printed on a surface of the circuit board <NUM>. Based on different feeding parts <NUM> and different N dipoles <NUM>, the feeding part <NUM> and the N dipoles <NUM> may be located on an upper surface <NUM> of the circuit board <NUM>, may be located on a lower surface <NUM> of the circuit board <NUM>, or may be located on both an upper surface <NUM> and a lower surface <NUM>.

It can be understood that the N dipoles <NUM> and feeding parts <NUM> that are correspondingly connected to the N dipoles <NUM> may all be located on a same outer surface of the circuit board <NUM>. However, in some other embodiments, the vertically polarized high-density antenna <NUM> may alternatively be in an antenna form of a sheet metal structure. In this case, each dipole <NUM> is of a metal structure and has specific rigidity and strength. In this form, the circuit board <NUM> may be omitted.

In this application, the dipole <NUM> in the vertically polarized high-density antenna <NUM> may be a dipole element or a monopole element, and correspondingly, the vertically polarized high-density antenna <NUM> is a dipole antenna or a monopole antenna. The feeding part <NUM> may be disposed differently based on different forms of the dipole <NUM>. <FIG> shows a structure in which a vertically polarized high-density antenna <NUM> is a dipole antenna. In this structure, the dipole <NUM> includes an upper dipole <NUM> and a lower dipole <NUM>, the upper dipole <NUM> is located on the upper surface <NUM> of the circuit board <NUM>, and the lower dipole <NUM> is located on the lower surface <NUM> of the circuit board <NUM>.

The feeding part <NUM> forms a double-sided parallel microstrip line power division network. The feeding part <NUM> includes a part located on the upper surface <NUM>, and the part is used to feed each upper dipole <NUM>; and the feeding part <NUM> includes a part located on the lower surface <NUM>, and the part is used to feed each lower dipole <NUM>. <FIG> and <FIG> are schematic diagrams of planes of the upper surface <NUM> and the lower surface <NUM> in this embodiment. The feeding part <NUM> is used as a double-sided parallel microstrip line power division network, and an upper part and a lower part of the feeding portion <NUM> have a same shape. The upper dipole <NUM> and the lower dipole <NUM> may have a same shape. It can be understood that, in some other embodiments, the upper dipole <NUM> and the lower dipole <NUM> may alternatively have different shapes, or the upper dipole <NUM> and the lower dipole <NUM> may alternatively be distributed in a mirroring manner with respect to the feeding part <NUM>.

<FIG> and <FIG> each shows a structure of the feeding part <NUM> in this application. The feeding part <NUM> may include a first power splitter <NUM>, a plurality of ohm transmission lines <NUM>, a plurality of impedance conversion lines <NUM>, and a second power splitter <NUM>. The second power splitter <NUM> may be a two-way power splitter, and the first power splitter <NUM> may be selected based on the quantity of dipoles <NUM>. For example, in the example shown in <FIG>, there are eight dipoles, and when the second power splitter <NUM> is a two-way power splitter, the first power splitter <NUM> may be a four-way power splitter. Therefore, eight feeding lines may be led from a feeding point of the feeding part <NUM> through the first power splitter <NUM> and the second power splitter <NUM>, to feed the eight dipoles <NUM> respectively. The first power splitter <NUM> of the feeding part <NUM> may be located at the antenna phase center.

For example, as shown in <FIG>, four output ends of the first power splitter <NUM> may be connected to four impedance conversion lines <NUM>, and the other end of each impedance conversion line <NUM> is connected to one end of one ohm transmission line <NUM>. The impedance conversion line <NUM> may be used to implement impedance matching between the ohm transmission line <NUM> and the first power splitter <NUM>. The other end of each ohm transmission line <NUM> is connected to one second power splitter <NUM>. Two output ends of the second power splitter <NUM> each are connected to one upper dipole <NUM>. Therefore, after dividing one path of current input into the feeding part <NUM> into four paths, the first power splitter <NUM> may output the four paths of currents through the four output ends. The four paths of currents are respectively transmitted to four second power splitters <NUM> through the four impedance conversion lines <NUM> and four ohm transmission lines <NUM> connected to the four impedance conversion lines <NUM>, and each second power splitter <NUM> may divide a received current into two paths, and respectively output the two paths of currents to two adjacent upper dipoles <NUM>, to feed the two adjacent upper dipoles <NUM>.

In an embodiment, the impedance conversion line <NUM> may be a <NUM>/<NUM> wavelength impedance conversion line, and the ohm transmission line <NUM> may be a <NUM> ohm microstrip line. However, on the lower surface <NUM> shown in <FIG>, the structure of the feeding part <NUM> is also similar to that on the upper surface <NUM> shown in <FIG>, and a current is respectively transferred to each lower dipole <NUM>. Details are not described herein in this application.

In <FIG>, only an example in which N is <NUM> is used for description. For another case in which N is an even number, refer to the foregoing examples. A difference is that when N is a different even number, the feeding part <NUM> includes a different first power splitter <NUM>, and the feeding part <NUM> also includes different quantities of impedance conversion lines <NUM> and different quantities of ohm transmission lines <NUM>. For example, when N is <NUM>, a first power splitter in an upper surface network and a first power splitter in a lower surface network may be three-way power splitters. Correspondingly, the first power splitter may be connected to three impedance conversion lines <NUM>, the three impedance conversion lines <NUM> are connected to three ohm transmission lines <NUM>, each ohm transmission line <NUM> is connected to one two-way second power splitter <NUM>, and each second power splitter <NUM> may be connected to two upper dipoles <NUM> or lower dipoles <NUM>.

It can be understood that when N is an odd number, refer to <FIG>. A feeding part <NUM> located on the upper surface <NUM> of the circuit board <NUM> may include one first power splitter <NUM>, a plurality of impedance conversion lines <NUM>, and a plurality of ohm transmission lines <NUM>. As shown in <FIG>, that N is <NUM> is used as an example. The first power splitter <NUM> may be a five-way power splitter, the first power splitter <NUM> may be connected to five impedance conversion lines <NUM>, the other end of each impedance conversion line <NUM> is connected to one ohm transmission line <NUM>, and a tail end of each ohm transmission line <NUM> may be connected to one upper dipole <NUM> (which is identified as a dipole <NUM> in <FIG>). Correspondingly, a feeding part <NUM> located on the lower surface <NUM> of the circuit board <NUM> has a same structure as the upper surface <NUM>, and each lower dipole <NUM> is also connected to one end of one ohm transmission line <NUM> on the lower surface <NUM>.

For example, <FIG> also shows a structure in which the dipole <NUM> is L-shaped. As shown in <FIG>, the L-shaped dipole <NUM> has a radial part 21a and a non-radial part 21b, and the radial part 21a points to the antenna phase center. The non-radial part 21b may be approximately disposed perpendicular to the radial part 21a. <FIG> shows merely a possible implementation of the dipole <NUM> provided in this embodiment of this application. In some other possible implementations, the dipole <NUM> may alternatively be of another shape, for example, any shape such as a trapezoidal shape, a bent structure, a T-shape, or a Y-shape.

For example, <FIG> shows a structure in which the vertically polarized high-density antenna <NUM> is a monopole antenna. As shown in <FIG>, the vertically polarized high-density antenna <NUM> includes eight dipoles <NUM>, a feeding part <NUM>, a grounding part <NUM>, and a circuit board <NUM>. The eight dipoles <NUM> are all located on the upper surface <NUM> of the circuit board <NUM>, and the feeding part <NUM> is also located on the upper surface <NUM>. The grounding part <NUM> is located on the lower surface <NUM> of the circuit board <NUM>. In the illustrated embodiment, the grounding part <NUM> is annular.

With reference to <FIG>, in this embodiment, the feeding part <NUM> may also include a first power splitter <NUM>, a plurality of ohm transmission lines <NUM>, a plurality of impedance conversion lines <NUM>, and a second power splitter <NUM>. A structure of the feeding part is similar to that shown in <FIG>, and the second power splitter <NUM> is connected to each dipole <NUM>. For specific settings of the feeding part <NUM> and the dipole <NUM>, refer to related descriptions in <FIG>. Details are not described herein again in this application. The grounding part <NUM> forms an inner conductor of the monopole antenna, to improve radiation efficiency of each dipole <NUM>. In an embodiment, the grounding part <NUM> is also located at a center of a projection <NUM>' of the vertically polarized high-density antenna <NUM>, and the grounding part <NUM> and a projection of each dipole <NUM> are flush or has a gap.

In this embodiment of this application, when the plurality of dipoles <NUM> are arranged in a circle, a nearest distance D2 between each dipole <NUM> and the antenna phase center may be adjusted, to further adjust an azimuth of the vertically polarized high-density antenna <NUM>, in other words, adjust a coverage area of the vertically polarized high-density antenna <NUM> in a horizontal direction. For example, a distance D2 between a single dipole <NUM> and the antenna phase center meets a condition: <NUM>/8λ ≤ D2 ≤ <NUM>/2λ.

Referring to the embodiment in <FIG>, in this application, the vertically polarized high-density antenna <NUM> may be further provided with a plurality of azimuth reflectors <NUM>. The plurality of azimuth reflectors <NUM> are also distributed in a circle, and a maximum of one azimuth reflector <NUM> is disposed between two adjacent dipoles <NUM>. A length direction of the azimuth reflector <NUM> passes through a plane on which the plurality of dipoles <NUM> are located. In other words, the azimuth reflector <NUM> may be disposed parallel to the polarization direction of the vertically polarized high-density antenna <NUM>. Simultaneously referring to <FIG>, the azimuth reflector <NUM> includes a first reflection section <NUM> and a second reflection section <NUM> in the length direction of the azimuth reflector <NUM>. The first reflection section <NUM> is located on a side that is of the dipole <NUM> and that is away from the bottom plate <NUM>, and the second reflection section <NUM> is located between the dipole <NUM> and the bottom plate <NUM>.

Further refer to <FIG> for understanding. In the schematic diagram of <FIG>, there are four azimuth reflectors <NUM>, and the four azimuth reflectors <NUM> are also evenly distributed in a circle, and each azimuth reflector <NUM> is located between two adjacent dipoles <NUM>. The four azimuth reflectors <NUM> are paired, and each pair of azimuth reflectors <NUM> is symmetrically distributed with respect to the antenna phase center. The azimuth reflector <NUM> may reflect a signal beam in the horizontal direction of the vertically polarized high-density antenna <NUM>, and the azimuth reflectors <NUM> are disposed at intervals, so that the radiation pattern of the vertically polarized high-density antenna <NUM> is even, and a radiation capability of the vertically polarized high-density antenna <NUM> in the range of <NUM> degrees in the horizontal direction is improved.

In an embodiment, a distance D3 between a single azimuth reflector <NUM> and the antenna phase center is greater than or equal to the distance D2 between the dipole <NUM> and the antenna phase center, and is less than or equal to a maximum distance between the dipole <NUM> and the antenna phase center. In other words, D3 meets a condition: D2 ≤ D3 ≤ (D2+L2). It may also be described as follows: A projection of the azimuth reflector <NUM> on the bottom plate <NUM> is located within an annular region enclosed by the dipoles <NUM>. Therefore, the azimuth reflector <NUM> can reflect the signal beam of the vertically polarized high-density antenna <NUM> in the horizontal direction, and control a horizontal coverage area of the vertically polarized high-density antenna <NUM> to be small.

Refer to <FIG> again. The azimuth reflector <NUM> has a length L3 in the polarization direction of the azimuth reflector <NUM>. In an embodiment, the length L3 of the azimuth reflector <NUM> is further controlled to meet a condition: <NUM>/5λ ≤ L3 ≤ λ, to ensure a distance in which the azimuth reflector <NUM> performs an action on the signal beam. In addition, on a side that is of the azimuth reflector <NUM> and that is close to the bottom plate <NUM>, namely, on a side of the second reflection section <NUM> of the azimuth reflector <NUM>, the azimuth reflector <NUM> and the bottom plate <NUM> are further disposed by being spaced from each other, and it may be set that a spacing distance D4 meets a condition: D4 ≤ <NUM>/4λ. The azimuth reflector <NUM> and the bottom plate <NUM> are spaced from each other, to avoid too long distance in which the azimuth reflector <NUM> performs an action, causing a too large coverage area of the vertically polarized high-density antenna <NUM> in the horizontal direction. It can be understood that, in the embodiment in which the vertically polarized high-density antenna <NUM> includes the circuit board <NUM>, the azimuth reflector <NUM> may be fastened to the circuit board <NUM>, and the azimuth reflector <NUM> is disposed by being spaced from the bottom plate <NUM>. However, when the vertically polarized high-density antenna <NUM> is of a sheet metal structure, the vertically polarized high-density antenna <NUM> does not include the circuit board <NUM>, the azimuth reflector <NUM> may also be fastened to the bottom plate <NUM>, and the azimuth reflector <NUM> and the bottom plate <NUM> need to be isolated from each other.

In the schematic diagram of <FIG>, the azimuth reflector <NUM> is also provided with an azimuth switch <NUM>. The azimuth switch <NUM> may also be used to switch the azimuth reflector <NUM> between an off state and an operating state. It can be understood that, that the control circuit <NUM> controls the operating mode of the reconfigurable antenna <NUM> may further include: The control circuit <NUM> controls the azimuth switch <NUM>. Specifically, when each azimuth switch <NUM> on each reflector <NUM> is in an operating state, the vertically polarized high-density antenna <NUM> may be in the omnidirectional mode. In this case, coverage areas of the vertically polarized high-density antennas <NUM> in the range of <NUM> degrees in the horizontal direction tend to be consistent based on the antenna phase center. However, as mentioned above, when a distance between access points <NUM> is large, the reconfigurable antenna <NUM> may further implement signal coverage in a super-large-angle directional mode. In this case, only azimuth switches <NUM> of two adjacent azimuth reflectors <NUM> may be controlled to be in an operating state, and the other azimuth switches <NUM> are in an opened state, so that the vertically polarized high-density antenna <NUM> is in the directional mode.

Refer to the schematic diagram of <FIG>, when the vertically polarized high-density antenna <NUM> is in the omnidirectional mode (which is shown by using a solid line in <FIG>), a coverage area of the vertically polarized high-density antenna <NUM> in the range of <NUM> degrees is even. However, when the vertically polarized high-density antenna <NUM> is in the directional mode, as shown by a dashed line in the figure, a gain increase of <NUM> decibels of the vertically polarized high-density antenna <NUM> in a <NUM>-degree direction is achieved, and a signal coverage area in the direction is wider. However, two adjacent azimuth switches <NUM> have different locations, and a wider directional coverage area of the vertically polarized high-density antenna <NUM> in this application in a <NUM>-degree, <NUM>-degree, or <NUM>-degree direction is achieved. It can be understood that, under control of the operating state of the controllable reflector <NUM> in the reconfigurable antenna <NUM>, a pitch angle of the reconfigurable antenna <NUM> in the directional mode in this application may also be correspondingly adjusted, and a gain of <NUM> decibel to <NUM> decibels is realized at a preset angle, to obtain a greater signal coverage area in the directional mode.

Refer to <FIG> again. In this implementation, when the vertically polarized high-density antenna <NUM> is in the directional mode, as shown by a dashed line in <FIG>, the signal coverage area of the vertically polarized high-density antenna <NUM> may be extended to a range with a radius of <NUM>. It can be understood that a coverage area in the directional mode may also be adjusted based on a scenario requirement. In this application, a maximum coverage area of the reconfigurable antenna <NUM> may alternatively exceed the range of the radius of <NUM> or smaller than the range of the radius of <NUM>.

It should be noted that the schematic diagram of <FIG> is described based on an embodiment in which there are four azimuth reflectors <NUM>, and the four azimuth reflectors <NUM> are evenly distributed in a circle. In some other embodiments, the four azimuth reflectors <NUM> may alternatively be distributed in an uneven manner, and corresponding directional coverage angles are adjusted correspondingly. Alternatively, for the reconfigurable antenna <NUM> in this application, another quantity of azimuth reflectors <NUM> may alternatively be disposed based on a use requirement, and operating states of different azimuth reflectors <NUM> cooperate, to implement directional coverage effects of different quantities of azimuth reflectors <NUM> at different angles.

Claim 1:
A reconfigurable antenna (<NUM>), comprising a bottom plate (<NUM>), a vertically polarized high-density antenna (<NUM>) wherein the bottom plate (<NUM>) is disposed in the polarization direction of the vertically polarized high-density antenna (<NUM>), and a controllable reflector (<NUM>), wherein
the controllable reflector (<NUM>) is located between the bottom plate (<NUM>) and the vertically polarized high-density antenna (<NUM>), and a projection of the controllable reflector (<NUM>) on the bottom plate (<NUM>) is at a center of a projection of the vertically polarized high-density antenna (<NUM>) on the bottom plate (<NUM>); and
the controllable reflector (<NUM>) comprises a switch (<NUM>), and the switch (<NUM>) is configured to enable the controllable reflector (<NUM>) to be in an operating state or an off state
characterized in that the controllable reflector (<NUM>) is further provided with an inductor structure (<NUM>), the inductor structure (<NUM>) and the switch (<NUM>) are connected in parallel, the inductor structure (<NUM>) and the switch (<NUM>) form a resonator, and a resonance frequency of the resonator falls within the operating frequency band of the vertically polarized high-density antenna (<NUM>).