阅读说明：本技术 一种北斗有源天线 (Beidou active antenna ) 是由 何方勇 陈锦鹏 张焕彬 高峰 孙功宪 许祥滨 于 2020-12-25 设计创作，主要内容包括：本申请适用于北斗卫星通信技术领域,提供了一种北斗有源天线,该北斗有源天线通过射频同轴电缆接收北斗卫星通信终端提供的电压恒定的直流电信号；其中的发射模块包括：可变增益放大单元,用于基于第一增益对滤波处理后的第一射频信号进行功率放大处理；功率放大单元,用于在开启后对功率放大处理后的第一射频信号再次进行功率放大处理；开关控制单元,用于获取滤波处理后的第一射频信号的功率对应的第一场强信号,并基于第一场强信号对功率放大单元进行开关控制；增益控制单元,用于获取再次进行功率放大处理后的第一射频信号的功率对应的第二场强信号,并基于第二场强信号对第一增益进行反向调节,解决了天线功放易损坏的问题。(The Beidou active antenna receives a direct current signal with constant voltage provided by a Beidou satellite communication terminal through a radio frequency coaxial cable; the transmitting module comprises: the variable gain amplification unit is used for carrying out power amplification processing on the filtered first radio-frequency signal based on a first gain; the power amplification unit is used for carrying out power amplification processing on the first radio-frequency signal after the power amplification processing after being started; the switch control unit is used for acquiring a first field intensity signal corresponding to the power of the first radio-frequency signal after filtering processing, and performing switch control on the power amplification unit based on the first field intensity signal; and the gain control unit is used for acquiring a second field intensity signal corresponding to the power of the first radio-frequency signal subjected to the power amplification processing again, and reversely adjusting the first gain based on the second field intensity signal, so that the problem that the antenna power amplifier is easy to damage is solved.)

1. The Beidou active antenna is characterized in that the Beidou active antenna is connected with a Beidou satellite communication terminal through a radio frequency coaxial cable, and the Beidou satellite communication terminal provides a direct current signal with constant voltage for the Beidou active antenna; big dipper active antenna includes emission module and receiving module, emission module includes:

the filtering unit is used for filtering a first radio frequency signal to be transmitted;

the variable gain amplification unit is connected with the filtering unit and used for carrying out power amplification processing on the first radio-frequency signal after filtering processing based on a first gain;

the power amplification unit is connected with the variable gain amplification unit and used for carrying out power amplification processing on the first radio-frequency signal after the power amplification processing after being started;

the switch control unit is connected with the filtering unit and the power amplifying unit and is used for acquiring a first field intensity signal corresponding to the power of the first radio-frequency signal after filtering processing and carrying out switch control on the power amplifying unit based on the first field intensity signal;

the passive transmitting antenna is connected with the power amplifying unit and used for converting the first radio-frequency signal subjected to the power amplifying processing again into a field signal and transmitting the field signal;

and the gain control unit is connected with the power amplification unit and the variable gain amplification unit and used for acquiring a second field intensity signal corresponding to the power of the first radio-frequency signal subjected to the power amplification processing again and reversely adjusting the first gain based on the second field intensity signal.

2. The Beidou active antenna of claim 1, wherein the switch control unit comprises:

the first field intensity induction subunit is connected with the filtering unit and used for carrying out field intensity induction on the first radio-frequency signal after filtering processing to obtain a first field intensity signal and converting the first field intensity signal into a corresponding first induction level;

the power amplifier switch control subunit is connected with the first field strength induction subunit and the power amplification unit and is used for generating a switch control signal according to the first induction level and a first preset level threshold; the switch control signal is used for controlling the power amplification unit to be turned on or off.

3. The Beidou active antenna of claim 2, wherein the power amplifier switch control subunit generates a turn-on signal when it is determined that the first sensing level is greater than or equal to the first preset level threshold; the starting signal is used for controlling the power amplification unit to be started.

4. The Beidou active antenna of claim 2, wherein the power amplifier switch control subunit generates a turn-off signal when it is determined that the first sensing level is less than the first preset level threshold; the turn-off signal is used for controlling the power amplification unit to turn off.

5. The Beidou active antenna of claim 1, wherein the variable gain amplification unit comprises:

the first-stage pre-amplification subunit is connected with the filtering unit and is used for performing first-stage power amplification processing on the first radio-frequency signal after filtering processing based on second gain, and the second gain is adjustable;

the second-stage pre-amplification subunit is used for performing second-stage power amplification processing on the first radio-frequency signal after the first-stage power amplification processing based on a third gain; wherein a product of the second gain and the third gain is the first gain.

6. The Beidou active antenna of claim 5, wherein the gain control unit comprises:

the second field intensity induction subunit is connected with the power amplification unit and used for carrying out field intensity induction on the first radio-frequency signal output by the power amplification unit to obtain a second field intensity signal and converting the second field intensity signal into a corresponding second induction level;

the gain adjusting subunit is connected with the second field strength induction subunit and the first-stage preamplifier subunit and is used for generating a reverse gain adjusting signal corresponding to the second induction level; wherein the inverse gain adjustment signal is used to inversely adjust the second gain.

7. The Beidou active antenna of claim 6, wherein the gain adjustment subunit generates a first reverse gain adjustment signal when the second sensing level is greater than a second preset level threshold; wherein the first inverse gain adjustment signal is used to adjust down the second gain.

8. The Beidou active antenna of claim 6, wherein the gain adjustment subunit generates a second reverse gain adjustment signal when the second sensing level is less than a third preset level threshold; the second reverse gain adjustment signal is used for increasing the second gain, and the third preset level threshold is smaller than the second preset level threshold.

9. The Beidou active antenna of claim 1, wherein the receiving module comprises:

the passive receiving antenna is used for receiving a second radio frequency signal;

the receiving access is connected with the passive receiving antenna and used for preprocessing the second radio frequency signal and sending the preprocessed second radio frequency signal to the Beidou satellite communication terminal; wherein the preprocessing at least comprises filtering processing and power amplification processing.

10. The Beidou active antenna of any of claims 1 through 9, further comprising:

the feed module is connected with the Beidou satellite communication terminal and used for separating a radio frequency signal and a direct current signal transmitted between the Beidou active antenna and the Beidou satellite communication terminal;

the combining module is connected with the feeding module, the transmitting module and the receiving module and is used for combining the radio-frequency signals of different frequency bands transmitted by the Beidou active antenna;

and the power supply processing module is connected with the feeding module, the transmitting module and the receiving module and is used for outputting direct current signals with constant voltage to the transmitting module and the receiving module.

11. The Beidou active antenna of any of claims 1 through 9, wherein the first gain is adjustable.

Technical Field

The application belongs to the technical field of big dipper satellite communication, especially relates to a big dipper active antenna.

Background

The Beidou satellite navigation system is a satellite navigation system with independent and independent intellectual property rights in China, and with the rapid development of the Beidou satellite navigation system, various Beidou satellite communication terminals based on the Beidou satellite navigation system are produced at the same time and are widely applied to the fields of electric power, agriculture, water conservancy, sea and land transportation and the like.

Big dipper satellite communication terminal communicates through big dipper antenna and big dipper satellite usually, and in some specific application environment, the unable integration of big dipper antenna is in big dipper satellite communication terminal, need handle the antenna, and traditional solution is connected big dipper satellite communication terminal and big dipper antenna through the radio frequency cable, and this radio frequency cable of accessible transmits radio frequency signal and power signal between big dipper satellite communication terminal and the big dipper antenna like this. The existing Beidou antenna designed based on the scheme needs to be powered by a low-voltage direct-current power supply mode when in a signal receiving state and needs to be powered by a high-voltage direct-current power supply mode when in a signal transmitting state, so that the Beidou antenna is in a high-low voltage switching state for a long time, the damage of an antenna power amplifier is easily caused, the reliability of the Beidou antenna is reduced, and the service life of the Beidou antenna is shortened; and the power of the radio frequency signal output by the Beidou antenna is unstable, so that the communication quality is poor or the power consumption of the Beidou antenna is high.

Disclosure of Invention

In view of this, this application embodiment provides a big dipper active antenna to solve current big dipper antenna design scheme and cause the damage of antenna power amplifier easily, reduce the reliability of big dipper antenna, shorten the life of big dipper antenna, and the power of the radio frequency signal of current big dipper antenna output is unstable, thereby leads to the relatively poor or higher problem of the consumption of big dipper antenna of communication quality.

The embodiment of the application provides a Beidou active antenna, wherein the Beidou active antenna is connected with a Beidou satellite communication terminal through a radio frequency coaxial cable, and the Beidou satellite communication terminal provides a direct current signal with constant voltage for the Beidou active antenna; big dipper active antenna includes emission module and receiving module, emission module includes:

the filtering unit is used for filtering a first radio frequency signal to be transmitted;

the variable gain amplification unit is connected with the filtering unit and used for carrying out power amplification processing on the first radio-frequency signal after filtering processing based on a first gain;

the power amplification unit is connected with the variable gain amplification unit and used for carrying out power amplification processing on the first radio-frequency signal after the power amplification processing after being started;

the switch control unit is connected with the filtering unit and the power amplifying unit and is used for acquiring a first field intensity signal corresponding to the power of the first radio-frequency signal after filtering processing and carrying out switch control on the power amplifying unit based on the first field intensity signal;

the passive transmitting antenna is connected with the power amplifying unit and used for converting the first radio-frequency signal subjected to the power amplifying processing again into a field signal and transmitting the field signal;

and the gain control unit is connected with the power amplification unit and the variable gain amplification unit and used for acquiring a second field intensity signal corresponding to the power of the first radio-frequency signal subjected to the power amplification processing again and reversely adjusting the first gain based on the second field intensity signal.

Optionally, the switch control unit includes:

the first field intensity induction subunit is connected with the filtering unit and used for carrying out field intensity induction on the first radio-frequency signal after filtering processing to obtain a first field intensity signal and converting the first field intensity signal into a corresponding first induction level;

the power amplifier switch control subunit is connected with the first field strength induction subunit and the power amplification unit and is used for generating a switch control signal according to the first induction level and a first preset level threshold; the switch control signal is used for controlling the power amplification unit to be turned on or off.

Optionally, the power amplifier switch control subunit generates an open signal when determining that the first sensing level is greater than or equal to the first preset level threshold; the starting signal is used for controlling the power amplification unit to be started.

Optionally, the power amplifier switch control subunit generates a turn-off signal when determining that the first sensing level is smaller than the first preset level threshold; the turn-off signal is used for controlling the power amplification unit to turn off.

Optionally, the variable gain amplifying unit includes:

the first-stage pre-amplification subunit is connected with the filtering unit and is used for performing first-stage power amplification processing on the first radio-frequency signal after filtering processing based on second gain, and the second gain is adjustable;

the second-stage pre-amplification subunit is used for performing second-stage power amplification processing on the first radio-frequency signal after the first-stage power amplification processing based on a third gain; wherein a product of the second gain and the third gain is the first gain.

Optionally, the gain control unit includes:

the second field intensity induction subunit is connected with the power amplification unit and used for carrying out field intensity induction on the first radio-frequency signal output by the power amplification unit to obtain a second field intensity signal and converting the second field intensity signal into a corresponding second induction level;

the gain adjusting subunit is connected with the second field strength induction subunit and the first-stage preamplifier subunit and is used for generating a reverse gain adjusting signal corresponding to the second induction level; wherein the inverse gain adjustment signal is used to inversely adjust the second gain.

Optionally, the gain adjustment subunit generates a first reverse gain adjustment signal when the second sensing level is greater than a second preset level threshold; wherein the first inverse gain adjustment signal is used to adjust down the second gain.

Optionally, the gain adjustment subunit generates a second reverse gain adjustment signal when the second sensing level is smaller than a third preset level threshold; the second reverse gain adjustment signal is used for increasing the second gain, and the third preset level threshold is smaller than the second preset level threshold.

Optionally, the receiving module includes:

the passive receiving antenna is used for receiving a second radio frequency signal;

the receiving access is connected with the passive receiving antenna and used for preprocessing the second radio frequency signal and sending the preprocessed second radio frequency signal to the Beidou satellite communication terminal; wherein the preprocessing at least comprises filtering processing and power amplification processing.

Optionally, the big dipper active antenna still includes:

the feed module is connected with the Beidou satellite communication terminal and used for separating a radio frequency signal and a direct current signal transmitted between the Beidou active antenna and the Beidou satellite communication terminal;

the combining module is connected with the feeding module, the transmitting module and the receiving module and is used for combining the radio-frequency signals of different frequency bands transmitted by the Beidou active antenna;

and the power supply processing module is connected with the feeding module, the transmitting module and the receiving module and is used for outputting direct current signals with constant voltage to the transmitting module and the receiving module.

Optionally, the first gain is adjustable.

Implement the big dipper active antenna that this application embodiment provided and have following beneficial effect:

the Beidou active antenna provided by the embodiment of the application is connected with the Beidou satellite communication terminal through the radio frequency coaxial cable, and the switch control unit in the transmitting module can realize automatic switch control on the power amplification unit based on the power of the first radio frequency signal, so that the automatic switch control on the signal receiving and sending states of the Beidou active antenna is realized, and the Beidou satellite communication terminal can provide a direct current signal with constant voltage for the Beidou active antenna, so that the Beidou active antenna always works in a constant voltage state, the problem that the antenna power amplifier is easy to damage can be effectively solved, the reliability of the Beidou active antenna is improved, and the service life of the Beidou active antenna is prolonged; meanwhile, the variable gain amplification unit and the gain control unit are arranged in the transmitting module of the active Beidou antenna, the field intensity signal corresponding to the power of the first radio-frequency signal output by the power amplification unit is obtained through the gain control unit, and the first gain is reversely adjusted based on the field intensity signal, so that the self-adaptive adjustment of the power amplification factor of the first radio-frequency signal can be realized, the power of the first radio-frequency signal output by the power amplification unit can be stabilized in a fixed range, the problems of poor communication quality caused by small power of the transmitting signal and high antenna power consumption caused by large power of the transmitting signal are avoided, the communication quality can be improved, and the power consumption of the active Beidou antenna is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a schematic diagram of a connection relationship between a beidou active antenna and a beidou satellite communication terminal provided in an embodiment of the present application;

fig. 2 is a schematic structural diagram of a Beidou active antenna provided in the embodiment of the present application;

fig. 3 is a schematic structural diagram of another Beidou active antenna provided in the embodiment of the present application;

fig. 4 is a schematic structural diagram of a Beidou active antenna provided in another embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It should be understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items. Furthermore, in the description of the present application and the appended claims, the terms "first," "second," "third," and the like are used for distinguishing between descriptions and not necessarily for describing or implying relative importance.

It should also be appreciated that reference throughout this specification to "one embodiment" or "some embodiments," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the present application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," or the like, in various places throughout this specification are not necessarily all referring to the same embodiment, but rather "one or more but not all embodiments" unless specifically stated otherwise. The terms "comprising," "including," "having," and variations thereof mean "including, but not limited to," unless expressly specified otherwise.

Referring to fig. 1, fig. 1 is a schematic diagram illustrating a connection relationship between a Beidou active antenna and a Beidou satellite communication terminal according to an embodiment of the present application. As shown in fig. 1, the beidou active antenna 10 provided in the embodiment of the present application may be connected to a beidou satellite communication terminal 30 through a radio frequency coaxial cable 20. By way of example and not limitation, the Beidou satellite communication terminal 30 may be an electricity metering device for collecting electrical parameter values recorded by an electricity meter.

Specifically, the Beidou active antenna 10 is provided with a unique communication interface, namely a radio frequency interface 11. The type of the radio frequency interface 11 may be set according to actual requirements, and is not limited herein, for example, the type of the radio frequency interface 11 may be a Nut (Nut, N) type interface, a miniature precision version a (SMA) interface, or a radio frequency interface (TNC interface) of TNC electrical corporation.

The Beidou active antenna 10 is connected with one end of a radio frequency coaxial cable 20 through a radio frequency interface 11 of the Beidou active antenna, and the other end of the radio frequency coaxial cable 20 is connected with a Beidou satellite communication terminal 30. Radio frequency signals and direct current signals can be transmitted between the Beidou active antenna 10 and the Beidou satellite communication terminal 30 through the radio frequency coaxial cable 20, namely, transmission of two different signals can be realized by connecting one radio frequency coaxial cable 20 between the Beidou active antenna 10 and the Beidou satellite communication terminal 30, so that the cost can be reduced, and the installation is convenient.

In the embodiment of the application, big dipper satellite communication terminal 30 provides the invariable direct current signal of voltage for big dipper active antenna 10, no matter big dipper active antenna 10 is in signal reception state or signal transmission state promptly, big dipper satellite communication terminal 30 is unchangeable all the time for the voltage of the direct current signal of big dipper active antenna 10 provides, can effectively solve the fragile problem of antenna power amplifier like this, the reliability of big dipper active antenna has been improved, big dipper active antenna's life has been prolonged.

Please refer to fig. 2, fig. 2 is a schematic structural diagram of a Beidou active antenna according to an embodiment of the present application. As shown in fig. 2, the beidou active antenna 10 may include a transmitting module 12 and a receiving module 13.

The transmitting module 12 specifically includes:

the filtering unit 121 is configured to perform filtering processing on the first radio frequency signal to be transmitted.

A variable gain amplifying unit 122, connected to the filtering unit 121, for performing power amplification processing on the filtered first radio frequency signal based on the first gain; wherein the first gain is adjustable.

And the power amplifying unit 123 is connected to the variable gain amplifying unit 122, and is configured to perform power amplification processing on the first radio frequency signal after power amplification processing again after being turned on.

And the switching control unit 124 is connected to the filtering unit 121 and the power amplifying unit 123, and is configured to acquire a first field strength signal corresponding to the power of the filtered first radio frequency signal, and perform switching control on the power amplifying unit 123 based on the first field strength signal.

And the passive transmitting antenna 125 is connected to the power amplifying unit 123, and is configured to convert the first radio frequency signal subjected to the power amplifying processing again into a field signal and transmit the field signal.

And the gain control unit 126 is connected to the power amplification unit 123 and the variable gain amplification unit 122, and is configured to acquire a second field strength signal corresponding to the power of the first radio-frequency signal after the power amplification processing is performed again, and perform reverse adjustment on the first gain based on the second field strength signal.

In this embodiment of the application, because the signal transmission frequency of big dipper active antenna 10 needs to be in the L frequency channel, consequently, filtering unit 121 receives the first radio frequency signal back that comes from big dipper satellite communication terminal 30, filters the clutter that the frequency is not in the L frequency channel in the first radio frequency signal, and in this embodiment of this application, the frequency of first radio frequency signal is in the L frequency channel promptly. In a specific application, the center frequency of the L-band may be 1615.68 megahertz (MHz), and the L-band may be 1615.68MHz ± 4.08 MHz.

In this embodiment of the application, the field strength value of the first field strength signal corresponding to the power of the first radio frequency signal acquired by the switch control unit 124 is positively correlated with the power of the filtered first radio frequency signal, that is, when the power of the filtered first radio frequency signal is higher, the field strength value of the first field strength signal corresponding to the power of the first radio frequency signal acquired by the switch control unit 124 is higher; when the power of the first radio frequency signal after the filtering process is smaller, the field strength value of the first field strength signal corresponding to the power of the first radio frequency signal acquired by the switch control unit 124 is smaller.

In specific application, when the beidou satellite communication terminal 30 transmits a radio frequency signal through the beidou active antenna 10, the power of the first radio frequency signal output by the filtering unit 121 is usually large, and at this time, the field intensity value of the first field intensity signal corresponding to the power of the first radio frequency signal acquired by the switch control unit 124 is also large; when the big dipper active antenna 10 does not transmit the radio frequency signal, the power of the first radio frequency signal output by the filtering unit 121 is usually smaller, and at this time, the field strength value of the first field strength signal corresponding to the power of the first radio frequency signal acquired by the switch control unit 124 is also smaller.

Therefore, in an embodiment of the present application, when detecting that the field strength value of the first field strength signal corresponding to the power of the first radio frequency signal is greater than the preset field strength threshold, the switch control unit 124 indicates that the big dipper active antenna needs to transmit the radio frequency signal to the outside at this time, so that the switch control unit 124 may control the power amplification unit 123 to turn on, so that the power amplification unit 123 performs power amplification processing on the filtered first radio frequency signal, and further, the power of the first radio frequency signal output by the power amplification unit 123 meets the transmission requirement.

In another embodiment of the present application, when detecting that the field strength value of the first field strength signal corresponding to the power of the first radio frequency signal is greater than the preset field strength threshold, the switch control unit 124 indicates that the Beidou active antenna does not need to transmit the radio frequency signal outwards at this time, and therefore the switch control unit 124 may control the power amplification unit 123 to be turned off, so as to reduce the power consumption of the Beidou active antenna.

This application embodiment can realize the automatic switch control to power amplification unit 123 based on the power size of the first radio frequency signal that emission module 12 received to realized the automatic switch-over control to big dipper active antenna's signal receiving and dispatching state, can also reduce big dipper active antenna's consumption simultaneously.

In this embodiment of the application, the field strength value of the second field strength signal corresponding to the power of the first radio frequency signal acquired by the gain control unit 126 is positively correlated with the power of the first radio frequency signal output by the power amplification unit 123, that is, when the power of the first radio frequency signal output by the power amplification unit 123 is higher, the field strength value of the second field strength signal corresponding to the power of the first radio frequency signal acquired by the gain control unit 126 is higher; when the power of the first radio frequency signal output by the power amplification unit 123 is smaller, the field strength value of the second field strength signal corresponding to the power of the first radio frequency signal acquired by the gain control unit 126 is smaller.

The reversely adjusting the first gain by the gain control unit 126 based on the second field strength signal corresponding to the acquired power of the first radio frequency signal may specifically include: when the field intensity value of the second field intensity signal corresponding to the power of the first radio frequency signal is greater than the first preset field intensity value threshold, the first gain is reduced, so that the power of the first radio frequency signal output by the power amplification unit 123 is reduced; when the field strength value of the second field strength signal corresponding to the power of the first radio frequency signal is smaller than the second preset field strength threshold, the first gain is increased, so that the power of the first radio frequency signal output by the power amplification unit 123 is increased, and thus the power of the first radio frequency signal output by the power amplification unit 123 is always stabilized between the power corresponding to the second preset field strength threshold and the power corresponding to the first preset field strength threshold. Wherein the second preset field intensity threshold is smaller than the first preset field intensity threshold.

As can be seen from the above, the big dipper active antenna provided by the embodiment of the application is connected with the big dipper satellite communication terminal through the radio frequency coaxial cable, and the switch control unit in the transmitting module can realize automatic switch control on the power amplifying unit based on the power of the first radio frequency signal, so as to realize automatic switch control on the signal receiving and sending states of the big dipper active antenna, so that the big dipper satellite communication terminal can provide a direct current signal with constant voltage for the big dipper active antenna, so that the big dipper active antenna always works in a constant voltage state, thereby effectively solving the problem that the power amplifier antenna is easy to damage, improving the reliability of the big dipper active antenna, and prolonging the service life of the big dipper active antenna; meanwhile, the variable gain amplification unit and the gain control unit are arranged in the transmitting module of the active Beidou antenna, the field intensity signal corresponding to the power of the first radio-frequency signal output by the power amplification unit is obtained through the gain control unit, and the first gain is reversely adjusted based on the field intensity signal, so that the self-adaptive adjustment of the power amplification factor of the first radio-frequency signal can be realized, the power of the first radio-frequency signal output by the power amplification unit can be stabilized in a fixed range, the problems of poor communication quality caused by small power of the transmitting signal and high antenna power consumption caused by large power of the transmitting signal are avoided, the communication quality can be improved, and the power consumption of the active Beidou antenna is reduced.

Please refer to fig. 3, fig. 3 is a schematic structural diagram of a beidou active antenna according to another embodiment of the present application. As shown in fig. 3, in this embodiment, the switch control unit 124 may specifically include:

the first field strength sensing subunit 1241 is connected to the filtering unit 121, and is configured to perform field strength sensing on the filtered first radio frequency signal to obtain a first field strength signal, and convert the first field strength signal into a corresponding first sensing level.

A power amplifier switch control subunit 1242, connected to the first field strength sensing subunit 1241 and the power amplifying unit 123, for generating a switch control signal according to the first sensing level and a first preset level threshold; the switch control signal is used to control the power amplification unit 123 to be turned on or off.

In a specific application, the first field strength sensing subunit 1241 may be a field strength detection circuit, and the field strength detection circuit may convert the sensed first field strength signal into a corresponding first sensing level according to a conversion relationship between a field strength value of the field strength signal and the sensing level. The larger the field intensity value of the first field intensity signal is, the higher the corresponding first induction level is. In a specific application, the field intensity detection circuit can be composed of a detection circuit and a filter circuit.

In this embodiment, after the power amplifier switch control subunit 1242 receives the first sensing level output by the first field strength sensing subunit 1241, the first sensing level is compared with a first preset level threshold.

The first preset level threshold may be determined according to an induced level corresponding to a radio frequency signal output by the filtering unit 121 when the big dipper active antenna 10 transmits the radio frequency signal.

In an implementation manner of this embodiment, the power amplifier switch control subunit 1242 may generate a start signal when determining that the first sensing level is greater than or equal to the first preset level threshold; the turn-on signal is used to control the power amplification unit 123 to turn on. In another implementation manner of this embodiment, the power amplifier switch control subunit 1242 may generate a turn-off signal when it is determined that the first sensing level is smaller than the first preset level threshold; the shutdown signal is used to control the power amplifying unit 123 to be turned off.

Referring to fig. 3, in another embodiment of the present application, the variable gain amplifying unit 122 may specifically include:

the first-stage preamplification subunit 1221 is connected to the filtering unit 121, and is configured to perform first-stage power amplification processing on the filtered first radio-frequency signal based on the second gain; wherein the second gain is adjustable.

A second-stage pre-amplifying subunit 1222, configured to perform a second-stage power amplification processing on the first radio-frequency signal after the first-stage power amplification processing based on a third gain; wherein the third gain is not adjustable, and the product of the second gain and the third gain is the first gain.

Further, the gain control unit 126 may specifically include:

the second field strength sensing subunit 1261 is connected to the power amplifying unit 123, and is configured to perform field strength sensing on the first radio frequency signal output by the power amplifying unit 123 to obtain a second field strength signal, and convert the second field strength signal into a corresponding second sensing level.

A gain adjustment subunit 1262, connected to the second field strength sensing subunit 1261 and the first stage preamplifier subunit 1221, and configured to generate a reverse gain adjustment signal corresponding to the second sensing level; wherein the inverse gain adjustment signal is used to inversely adjust the second gain.

In a specific application, the second field strength sensing subunit 1261 may be a field strength detection circuit, and the field strength detection circuit may convert the sensed second field strength signal into a corresponding second sensing level according to a conversion relationship between a field strength value of the field strength signal and the sensing level. Wherein, the larger the field strength value of the second field strength signal is, the higher the corresponding second induction level is. In a specific application, the field intensity detection circuit can be composed of a detection circuit and a filter circuit.

In this embodiment, after the gain adjustment subunit 1262 receives the second sensing level output by the second field strength sensing subunit 1261, the second sensing level may be compared with a second preset level threshold and a third preset level threshold, and a corresponding anti-sounding gain adjustment signal is generated based on the comparison result.

The second preset level threshold may be determined according to a preset maximum power of the transmission signal, and the third preset level threshold may be determined according to a preset small power of the transmission signal.

In one implementation manner of this embodiment, the gain adjustment subunit 1262 generates a first reverse gain adjustment signal when it is determined that the second sensing level is greater than the second preset level threshold; wherein the first inverse gain adjustment signal is used to adjust down the second gain. In another implementation manner of this embodiment, the gain adjustment subunit 1262 generates a second inverse gain adjustment signal when it is determined that the second sensing level is less than the third preset level threshold; wherein the second inverse gain adjustment signal is used to adjust up the second gain.

Referring to fig. 3, in another embodiment of the present application, the receiving module 13 may include:

and a passive receiving antenna 132 for receiving the second rf signal.

The receiving channel 131 is connected with the passive receiving antenna and used for preprocessing the second radio frequency signal and sending the preprocessed second radio frequency signal to the Beidou satellite communication terminal; the preprocessing at least comprises filtering processing and power amplification processing.

In this embodiment, the passive receiving antenna 132 may specifically convert the field signal based on the electromagnetic field transmission mode into the radio frequency signal based on the path transmission mode, so as to receive the second radio frequency signal.

In this embodiment, since the signal receiving frequency of the Beidou active antenna 10 needs to be within the S frequency band, the frequency of the second radio frequency signal needs to be within the S frequency band. In a specific application, the center frequency of the S band may be 2491.75MHz, and the S band may be 2491.75MHz ± 4.08 MHz.

In specific application, the receiving path 131 may perform filtering processing on a clutter signal of the second radio frequency signal, where the frequency is not within the S frequency band, and perform power amplification processing on the filtered second radio frequency signal, so that the power of the second radio frequency signal meets the signal receiving requirement of the Beidou active antenna.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a Beidou active antenna according to another embodiment of the present application. As shown in fig. 4, in this embodiment, the beidou active antenna 10 further includes:

and the feed module 14 is connected with the Beidou satellite communication terminal 30 and used for separating the radio frequency signal and the direct current signal transmitted between the Beidou active antenna 10 and the Beidou satellite communication terminal 30.

And the combining module 15 is connected with the feeding module 14, the transmitting module 12 and the receiving module 13, and is used for combining the radio frequency signals of different frequency bands transmitted by the Beidou active antenna 10.

And the power supply processing module 16 is connected with the feeding module 14, the transmitting module 12 and the receiving module 13, and is used for outputting a direct current signal with constant voltage to the transmitting module 12 and the receiving module 13.

In this embodiment, the feed module 14 separates the radio frequency signal and the direct current signal transmitted between the Beidou active antenna 10 and the Beidou satellite communication terminal 30, so that the radio frequency signal and the direct current signal are isolated from each other and are not affected by each other.

The combining module 15 is specifically configured to combine the radio frequency signal in the L frequency band and the radio frequency signal in the S frequency band, so that the two signals are transmitted on the same radio frequency link.

The power processing module 16 can process the dc signal with constant voltage provided by the beidou satellite communication terminal 30, and provide a constant working voltage for the transmitting module 12 and the receiving module 13.

It should be noted that the power processing module 16 supplies power to other modules in the beidou active antenna 10 in addition to the transmitting module 12 and the receiving module 13.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.