An antenna system and a control method thereof

Abstract

The application provides an antenna system and a control method thereof. The antenna system comprises a control unit, a feed network and a plurality of antenna branches. The antenna branch comprises a digital attenuator, a power amplifier and an antenna unit connected in sequence. The input end of the digital attenuator is connected to the output end of the feed network. The control end of the digital attenuator and the control end of the power amplifier are both connected to the control unit. The control unit determines a target excitation signal corresponding to a target branch according to sidelobe level information. The control unit adjusts the output impedance of the target power amplifier to match the target excitation signal and adjusts the attenuation amplitude of the target attenuator to match the target excitation signal according to the target excitation signal. By adjusting the output impedance of the target power amplifier and the attenuation amplitude of the target attenuator, the target power amplifier can output the target excitation signal. Because the output impedance is controlled to change, the target power amplifier can still be in a saturated power state and maintain the highest efficiency.

Description

Technical Field

[0001] This invention relates to the field of antennas, and more specifically, to an antenna system and its control method. Background Technology

[0002] To suppress sidelobes in the radiation pattern of an array antenna, the excitation signals of the array elements are typically weighted, using methods such as Chebyshev synthesis and Taylor synthesis. According to these synthesis methods, the excitation signals of all array elements except the center element need to be proportionally reduced. In practical arrays, attenuators are usually connected to adjust the output power to achieve excitation signals of different amplitudes.

[0003] However, the attenuation caused by the attenuator may prevent the antenna from achieving its highest efficiency output, which has become a problem of concern to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide an antenna system and its control method to improve the above-mentioned problems.

[0005] To achieve the above objectives, the technical solutions adopted in the embodiments of the present invention are as follows:

[0006] In a first aspect, embodiments of the present invention provide an antenna system, the antenna system comprising: a control unit, a feed network, and multiple antenna branches, wherein each antenna branch comprises a digitally controlled attenuator, a power amplifier, and an antenna element connected in sequence;

[0007] The input terminal of the digitally controlled attenuator is connected to the output terminal of the power supply network, and the control terminal of the digitally controlled attenuator and the control terminal of the power amplifier are both connected to the control unit;

[0008] The control unit is used to determine the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any of the antenna branches;

[0009] The control unit is used to adjust the output impedance of the target power amplifier to match the target excitation signal, and adjust the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the numerically controlled attenuator in the target branch.

[0010] Secondly, embodiments of the present invention provide an antenna system control method, applied to a control unit in the aforementioned antenna system, the method comprising:

[0011] The control unit determines the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any antenna branch;

[0012] The control unit adjusts the output impedance of the target power amplifier to match the target excitation signal, and adjusts the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the numerically controlled attenuator in the target branch.

[0013] Compared to existing technologies, this invention provides an antenna system and its control method. The antenna system includes a control unit, a feed network, and multiple antenna branches. Each antenna branch includes a digitally controlled attenuator, a power amplifier, and an antenna element connected sequentially. The input terminal of the digitally controlled attenuator is connected to the output terminal of the feed network, and the control terminals of the digitally controlled attenuator and the power amplifier are both connected to the control unit. The control unit is used to determine the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any antenna branch. The control unit is used to adjust the output impedance of the target power amplifier to match the target excitation signal and adjust the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the digitally controlled attenuator in the target branch. By adjusting the output impedance of the target power amplifier and the attenuation amplitude of the target attenuator, the target power amplifier can output the target excitation signal, and because the output impedance is changed in a controlled manner, the target power amplifier can still maintain saturated power and maximum efficiency.

[0014] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is one of the structural schematic diagrams of an antenna system provided in an embodiment of the present invention.

[0017] Figure 2 A schematic diagram of power and efficiency provided for an embodiment of the present invention.

[0018] Figure 3 This is a second schematic diagram of the antenna system provided in an embodiment of the present invention.

[0019] Figure 4This is a schematic diagram of the controllable load impedance modulation circuit provided in an embodiment of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0022] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0024] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed when in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0025] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0027] This invention provides an antenna system, please refer to... Figure 1 , Figure 1 This is one of the structural schematic diagrams of an antenna system provided in an embodiment of the present invention. The antenna system includes: a control unit, a feed network, and multiple antenna branches. Each antenna branch includes a digitally controlled attenuator, a power amplifier, and an antenna element connected in sequence. That is, the output terminal of the digitally controlled attenuator is connected to the input terminal of the power amplifier, and the output terminal of the power amplifier is connected to the input terminal of the antenna element. The number of antenna branches can be greater than or equal to 2.

[0028] The power supply network can be an equal power distribution network or an unequal power distribution network.

[0029] The input terminal of the digitally controlled attenuator is connected to the output terminal of the feed network, and the control terminals of the digitally controlled attenuator and the power amplifier are both connected to the control unit (for ease of illustration, only the connection relationship between one antenna branch and the control unit is shown in the figure).

[0030] The control unit is used to determine the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any antenna branch.

[0031] The control unit is used to adjust the output impedance of the target power amplifier to match the target excitation signal, and to adjust the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the numerically controlled attenuator in the target branch.

[0032] In the antenna system provided in this embodiment of the invention, by adjusting the output impedance of the target power amplifier and the attenuation amplitude of the target attenuator, the target power amplifier can output the target excitation signal, and because the output impedance is changed in a controlled manner, the target power amplifier can still be in saturated power state and maintain the highest efficiency.

[0033] For details, please refer to Figure 2 , Figure 2This diagram illustrates power and efficiency in an embodiment of the present invention. A1 corresponds to the power-efficiency curve when the output impedance of the target power amplifier is not adjusted to match the target excitation signal, and A2 corresponds to the power-efficiency curve when the output impedance of the target power amplifier is adjusted to match the target excitation signal. The comparison shows that in case A1, the efficiency decreases as the output power of the power amplifier decreases. In case A2, even if the output power of the power amplifier decreases, the amplifier can still maintain maximum efficiency because the output impedance of the target power amplifier is adjusted to match the target excitation signal.

[0034] Please refer to Figure 3 , Figure 3 This is a second schematic diagram of the antenna system provided in an embodiment of the present invention. The power amplifier includes an input matching circuit, a power amplifier chip, and a controllable load impedance modulation circuit. The input terminal of the input matching circuit is connected to the output terminal of the digitally controlled attenuator, the output terminal of the input matching circuit is connected to the input terminal of the power amplifier chip, the output terminal of the power amplifier chip is connected to the input terminal of the controllable load impedance modulation circuit, and the output terminal of the controllable load impedance modulation circuit is connected to the input terminal of the antenna element.

[0035] The control terminals of the power amplifier chip and the controllable load impedance modulation circuit (which serves as the control terminal of the power amplifier) ​​are both connected to the control unit.

[0036] Optionally, the control unit is used to send a control signal to the controllable load impedance modulation circuit according to the target excitation signal so that the load state of the controllable load impedance modulation circuit matches the target excitation signal.

[0037] The control unit can determine the control signal, bias voltage, and attenuation amplitude that match the target excitation signal by looking up a table.

[0038] In one alternative implementation, when the output power corresponding to the target excitation signal exceeds a preset boundary, such as being less than a set minimum power, the controllable load impedance modulation circuit can be adjusted to match the set minimum power, and the numerically controlled attenuator can be controlled to reduce the input power, thereby ultimately achieving the excitation signal requirements through power backoff.

[0039] It should be understood that the electrical signal output by the power supply network is transmitted to the digitally controlled attenuator via power distribution. After the digitally controlled attenuator processes the signal according to the corresponding attenuation amplitude, it transmits the attenuated electrical signal to the power amplifier. The power amplifier processes the received signal to generate the corresponding excitation signal and provides the excitation signal to the antenna unit. The antenna unit then emits the corresponding radio frequency signal according to the excitation signal.

[0040] Please refer to Figure 4 , Figure 4This is a schematic diagram of the controllable load impedance modulation circuit provided in an embodiment of the present invention. The controllable load impedance modulation circuit includes a first switch K1, a second switch K2, a third switch K3, a first variable capacitor C1, a second variable capacitor C2, a first variable inductor L1, and a second variable inductor L2.

[0041] The first terminal of the first switch K1 and the first terminal of the second switch K2 serve as the input terminals of the controllable load impedance modulation circuit (connected to the output terminal of the power amplifier chip). The second terminal of the first switch K1 is left floating. The third terminal of the first switch K1 is connected to one pole of the first variable capacitor C1. The fourth terminal of the first switch K1 is connected to one end of the first variable inductor L1. The other poles of the first variable capacitor C1 and the other end of the first variable inductor L1 are grounded.

[0042] The second terminal of the second switch K2 is connected to one pole of the second variable capacitor C2, the third terminal of the second switch K2 is connected to one terminal of the second variable inductor L2, the first terminal of the third switch K3 serves as the output terminal of the controllable load impedance modulation circuit (connected to the input terminal of the antenna unit), the second terminal of the third switch K3 is connected to the other pole of the second variable capacitor C2, and the third terminal of the third switch K3 is connected to the other terminal of the second variable inductor L2.

[0043] The control terminals of the first switch K1, the second switch K2, the third switch K3, the first variable capacitor C1, the second variable capacitor C2, the first variable inductor L1, and the second variable inductor L2 are all connected to the control unit.

[0044] Optionally, the control signals include a first switch control signal, a second switch control signal, a third switch control signal, a first capacitor control signal, a second capacitor control signal, a first inductor control signal, and a second inductor control signal;

[0045] The first switch control signal is used to switch the conduction relationship between the first terminal of the first switch K1 and the second, third and fourth terminals;

[0046] The second switch control signal is used to switch the conduction relationship between the first terminal and the second and third terminals of the second switch K2;

[0047] The third switch control signal is used to switch the conduction relationship between the first end and the second end, and the third end of the third switch K3. It should be noted that the third switch control signal is matched with the second switch control signal. That is, when the first end of the second switch K2 is connected to the second end, the first end of the third switch K3 is connected to the second end; when the first end of the second switch K2 is connected to the third end, the first end of the third switch K3 is connected to the third end.

[0048] The first capacitor control signal is used to adjust the capacitance value of the first variable capacitor C1;

[0049] The second capacitor control signal is used to adjust the capacitance value of the second variable capacitor C2;

[0050] The first inductor control signal is used to adjust the inductance value of the first variable inductor L1;

[0051] And the second inductor control signal is used to adjust the inductance value of the second variable inductor L2.

[0052] Optionally, the control unit is used to output a bias voltage to the power amplifier die that matches the target excitation signal.

[0053] The bias voltage serves as the operating voltage for power amplifier diodes. Using the DC power supplied by the bias voltage, the power amplifier diode converts small radio frequency (RF) signals into amplified RF signals by consuming DC power. By adjusting the bias voltage, the power amplifier diode can operate in different states, such as the well-known Class A, Class B, and Class AB amplifiers. By adjusting the bias voltage, i.e., the operating state, the power amplifier diode can produce different performance characteristics, such as saturated output power and efficiency.

[0054] Optionally, the control unit includes a controller and a bias voltage power supply circuit, the controller is connected to the bias voltage power supply circuit, and the output terminal of the bias voltage power supply circuit is connected to the control terminal of the power amplifier die;

[0055] The controller is used to send a corresponding trigger command to the bias voltage power supply circuit according to the target excitation signal, so that the bias voltage power supply circuit outputs a bias voltage that matches the target excitation signal.

[0056] Optionally, the controller is also connected to the control terminal of the controllable load impedance modulation circuit and the control terminal of the digitally controlled attenuator.

[0057] Optionally, the controller sends a control signal to the controllable load impedance modulation circuit according to the target excitation signal, so that the load state of the controllable load impedance modulation circuit matches the target excitation signal; the controller adjusts the attenuation amplitude of the target attenuator to match the target excitation signal.

[0058] It should be noted that the antenna system provided by the embodiments of the present invention can significantly improve the efficiency of amplitude-weighted active arrays. The excitation signal amplitude required for amplitude weighting can be accurately achieved. Taking the mature semiconductor process P10PA22 and an eleven-element Taylor-weighted, sidelobe-suppressed -20dB linear array as an example, calculations show that the efficiency of existing solutions can be improved by 1.6 times and 1.3 times respectively, and the average amplitude error of each channel is reduced by 0.47dB and 0.16dB respectively.

[0059] This invention also provides an antenna system control method, applied to the control unit in the antenna system described above. The antenna system control method includes S101 and S102, which are described in detail below.

[0060] S101, the control unit determines the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any antenna branch.

[0061] S102, the control unit adjusts the output impedance of the target power amplifier to match the target excitation signal according to the target excitation signal, and adjusts the attenuation amplitude of the target attenuator to match the target excitation signal. Here, the target power amplifier is the power amplifier in the target branch, and the target attenuator is the numerically controlled attenuator in the target branch.

[0062] In summary, the present invention provides an antenna system and its control method. The antenna system includes a control unit, a feed network, and multiple antenna branches. Each antenna branch includes a digitally controlled attenuator, a power amplifier, and an antenna element connected in sequence. The input terminal of the digitally controlled attenuator is connected to the output terminal of the feed network, and the control terminals of the digitally controlled attenuator and the power amplifier are both connected to the control unit. The control unit is used to determine the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any antenna branch. The control unit is used to adjust the output impedance of the target power amplifier to match the target excitation signal and adjust the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the digitally controlled attenuator in the target branch. By adjusting the output impedance of the target power amplifier and the attenuation amplitude of the target attenuator, the target power amplifier can output the target excitation signal, and because the output impedance is changed in a controlled manner, the target power amplifier can still maintain saturated power and maximum efficiency.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0064] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. An antenna system, characterized in that, The antenna system includes: a control unit, a feed network, and multiple antenna branches, wherein each antenna branch includes a digitally controlled attenuator, a power amplifier, and an antenna element connected in sequence. The input terminal of the digitally controlled attenuator is connected to the output terminal of the power supply network, and the control terminal of the digitally controlled attenuator and the control terminal of the power amplifier are both connected to the control unit; The control unit is used to determine the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any of the antenna branches; The control unit is used to adjust the output impedance of the target power amplifier to match the target excitation signal, and adjust the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the numerically controlled attenuator in the target branch; The power amplifier includes an input matching circuit, a power amplifier chip, and a controllable load impedance modulation circuit. The input terminal of the input matching circuit is connected to the output terminal of the digitally controlled attenuator, the output terminal of the input matching circuit is connected to the input terminal of the power amplifier chip, the output terminal of the power amplifier chip is connected to the input terminal of the controllable load impedance modulation circuit, and the output terminal of the controllable load impedance modulation circuit is connected to the input terminal of the antenna unit. The control terminal of the power amplifier chip and the controllable load impedance modulation circuit are both connected to the control unit.

2. The antenna system as described in claim 1, characterized in that, The control unit is used to send a control signal to the controllable load impedance modulation circuit according to the target excitation signal, so as to match the load state of the controllable load impedance modulation circuit with the target excitation signal.

3. The antenna system as described in claim 2, characterized in that, The controllable load impedance modulation circuit includes a first switch, a second switch, a third switch, a first variable capacitor, a second variable capacitor, a first variable inductor, and a second variable inductor. The first terminal of the first switch and the first terminal of the second switch serve as the input terminals of the controllable load impedance modulation circuit. The second terminal of the first switch is left floating. The third terminal of the first switch is connected to one pole of the first variable capacitor. The fourth terminal of the first switch is connected to one end of the first variable inductor. The other poles of the first variable capacitor and the other end of the first variable inductor are grounded. The second terminal of the second switch is connected to one pole of the second variable capacitor, the third terminal of the second switch is connected to one terminal of the second variable inductor, the first terminal of the third switch serves as the output terminal of the controllable load impedance modulation circuit, the second terminal of the third switch is connected to the other pole of the second variable capacitor, and the third terminal of the third switch is connected to the other terminal of the second variable inductor. The control terminals of the first switch, the second switch, the third switch, the first variable capacitor, the second variable capacitor, the first variable inductor, and the second variable inductor are all connected to the control unit.

4. The antenna system as described in claim 3, characterized in that, The control signals include a first switch control signal, a second switch control signal, a third switch control signal, a first capacitor control signal, a second capacitor control signal, a first inductor control signal, and a second inductor control signal; The first switch control signal is used to switch the conduction relationship between the first terminal and the second, third and fourth terminals of the first switch. The second switch control signal is used to switch the conduction relationship between the first terminal and the second and third terminals of the second switch; The third switch control signal is used to switch the conduction relationship between the first terminal and the second and third terminals of the third switch; The first capacitor control signal is used to adjust the capacitance value of the first variable capacitor; The second capacitor control signal is used to adjust the capacitance value of the second variable capacitor; The first inductor control signal is used to adjust the inductance value of the first variable inductor; And a second inductor control signal is used to adjust the inductance value of the second variable inductor.

5. The antenna system as described in claim 1, characterized in that, The control unit is used to output a bias voltage to the power amplifier die that matches the target excitation signal.

6. The antenna system as described in claim 1, characterized in that, The control unit includes a controller and a bias voltage power supply circuit. The controller is connected to the bias voltage power supply circuit, and the output terminal of the bias voltage power supply circuit is connected to the control terminal of the power amplifier chip. The controller is used to send a corresponding trigger command to the bias voltage power supply circuit according to the target excitation signal, so that the bias voltage power supply circuit outputs a bias voltage that matches the target excitation signal.

7. The antenna system as described in claim 6, characterized in that, The controller is also connected to the control terminal of the controllable load impedance modulation circuit and the control terminal of the digitally controlled attenuator.

8. A method for controlling an antenna system, characterized in that, The method, applied to the control unit in the antenna system according to any one of claims 1-7, comprises: The control unit determines the target excitation signal corresponding to the target branch based on the sidelobe level information, wherein the target branch is any antenna branch; The control unit adjusts the output impedance of the target power amplifier to match the target excitation signal, and adjusts the attenuation amplitude of the target attenuator to match the target excitation signal, wherein the target power amplifier is the power amplifier in the target branch, and the target attenuator is the numerically controlled attenuator in the target branch.

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