CN116736348A

CN116736348A - Radio frequency front-end circuit and satellite navigation system

Info

Publication number: CN116736348A
Application number: CN202310797717.2A
Authority: CN
Inventors: 王柯乔; 陈锦贤
Original assignee: Guangzhou Xaircraft Technology Co Ltd
Current assignee: Guangzhou Xaircraft Technology Co Ltd
Priority date: 2023-06-30
Filing date: 2023-06-30
Publication date: 2023-09-12

Abstract

The application discloses a radio frequency front-end circuit and a satellite navigation system. The radio frequency front-end circuit provided by the embodiment of the application comprises a frequency dividing circuit and a matrix switch, wherein the frequency dividing circuit comprises at least two input ends and at least four output ends, the matrix switch comprises at least four input ends and at least four output ends, the input end of the frequency dividing circuit is used for being connected with an antenna, and each output end of the frequency dividing circuit is respectively connected with each input end of the matrix switch; each input end of the matrix switch is correspondingly connected with each output end through a switching device, and the output end of the matrix switch is used for being connected with a receiver chip; the plurality of switching devices in the matrix switch are switched under at least three switching state combinations, so that the receiver chip can respectively execute three RTK positioning algorithms under various switching state combinations. By the technical means, the problems of high manufacturing cost and large volume of the radio frequency front-end circuit of the satellite navigation system in the prior art are solved, and the applicability of the satellite navigation system is improved.

Description

Radio frequency front-end circuit and satellite navigation system

Technical Field

The present application relates to the field of satellite navigation technologies, and in particular, to a radio frequency front end circuit and a satellite navigation system.

Background

All kinds of electronic equipment are provided with satellite navigation systems, and the satellite navigation systems can execute RTK positioning algorithms through satellite signals received by antennas to determine the positions and the postures of the electronic equipment. The satellite navigation system can accurately position the electronic equipment based on the multi-frequency signals received by one antenna, and can also perform orientation gesture measurement on the electronic equipment based on the single-frequency signals or the multi-frequency signals received by a plurality of antennas.

In the prior art, in order to realize the functions of accurate positioning and directional attitude measurement of a satellite navigation system, the satellite navigation system is provided with three radio frequency front-end circuits for respectively receiving the multi-frequency signals of a single antenna, the single-frequency signals of multiple antennas and the multi-frequency signals of multiple antennas. But the three radio frequency front-end circuits have higher manufacturing cost and larger volume, and are not beneficial to popularization and use of the satellite navigation system.

Disclosure of Invention

The application provides a radio frequency front-end circuit and a satellite navigation system, which solve the problems of high manufacturing cost and large volume of the radio frequency front-end circuit of the satellite navigation system in the prior art, ensure the excellent radio frequency performance of the radio frequency front end, simultaneously have lower manufacturing cost and smaller volume, and can be applied to various scenes, thereby improving the applicability of the satellite navigation system.

In a first aspect, the present application provides a radio frequency front-end circuit, comprising a frequency dividing circuit and a matrix switch, the frequency dividing circuit comprising at least two inputs and at least four outputs, the matrix switch comprising at least four inputs and at least four outputs, wherein:

the input end of the frequency dividing circuit is used for being connected with an antenna, and each output end of the frequency dividing circuit is respectively connected with each input end of the matrix switch; each input end of the matrix switch is correspondingly connected with each output end through a switching device, and the output end of the matrix switch is used for being connected with a receiver chip;

the plurality of switching devices in the matrix switch are switched under at least three switching state combinations, so that the receiver chip can respectively execute three RTK positioning algorithms under various switching state combinations.

In a second aspect, the present application provides a satellite navigation system comprising an antenna, a receiver chip and a radio frequency front-end circuit as described in the first aspect.

In the application, the radio frequency front-end circuit comprises a frequency dividing circuit and a matrix switch, wherein the frequency dividing circuit comprises at least two input ends and at least four output ends, the matrix switch comprises at least four input ends and at least four output ends, each input end of the frequency dividing circuit is correspondingly connected with an antenna, and each output end of the frequency dividing circuit is respectively connected with each input end of the matrix switch. The input end of the frequency dividing circuit receives signals transmitted by the antennas, the frequency dividing circuit can divide the signals transmitted by each antenna into signals of two frequency bands, and signals of different antennas of different frequency bands are transmitted to different output ends of the frequency dividing circuit, so that the input end of the matrix switch is connected with signals of a plurality of frequency bands transmitted by a plurality of antennas. The multiple switch devices in the matrix switch are switched under at least three switch state combinations, so that the receiver chip respectively receives single-antenna multi-frequency signals, multi-antenna single-frequency signals and multi-antenna multi-frequency signals under various switch state combinations, and three RTK positioning algorithms of single-antenna multi-frequency positioning, multi-antenna single-frequency directional attitude measurement and multi-antenna multi-frequency directional attitude measurement are respectively executed based on the single-antenna multi-frequency signals, the multi-antenna single-frequency signals and the multi-antenna multi-frequency signals. Through the technical means, the satellite navigation system respectively realizes single-antenna multi-frequency positioning, multi-antenna single-frequency directional attitude measurement and multi-antenna multi-frequency directional attitude measurement by using one radio-frequency front-end circuit, so that the manufacturing cost of the radio-frequency front-end circuit is greatly saved, the integration level of the radio-frequency front-end circuit is improved, the volume of the radio-frequency front-end circuit is reduced, the problems of high manufacturing cost and large volume of the radio-frequency front-end circuit of the satellite navigation system in the prior art are solved, the excellent radio-frequency performance of the radio-frequency front-end is ensured, meanwhile, the low manufacturing cost and the small volume are realized, the satellite navigation system can be applied to various scenes, and the applicability of the satellite navigation system is improved.

Drawings

FIG. 1 is a schematic block diagram of a radio frequency front-end circuit provided by an embodiment of the present application;

fig. 2 is a schematic diagram of a frequency dividing circuit according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a radio frequency front-end circuit according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a matrix switch according to an embodiment of the present application;

FIG. 5 is a first schematic diagram of a first switch state combination according to an embodiment of the present application;

FIG. 6 is a second schematic diagram of a first switch state combination provided by an embodiment of the present application;

FIG. 7 is a first schematic diagram of a second switch state combination provided by an embodiment of the present application;

FIG. 8 is a second schematic diagram of a second switch state combination provided by an embodiment of the present application;

FIG. 9 is a schematic diagram of a third switch state combination provided by an embodiment of the present application;

FIG. 10 is a schematic diagram of another matrix switch according to an embodiment of the present application;

in the figure, 10, a frequency dividing circuit; 11. an input terminal of the frequency dividing circuit; 12. an output terminal of the frequency dividing circuit; 13. a splitter; 131. a first splitter; 132. a second splitter; 14. a filter; 141. a first filter; 142. a second filter; 143. a third filter; 144. a fourth filter; 151. a first low noise amplifier; 152. a second low noise amplifier; 161. a first adjustable attenuator; 162. a second adjustable attenuator; 163. a third adjustable attenuator; 164. a fourth adjustable attenuator; 171. a first variable gain amplifier; 172. a second variable gain amplifier; 173. a third variable gain amplifier; 174. a fourth variable gain amplifier; 181. a first phase shifter; 182. a second phase shifter; 183. a third phase shifter; 184. a fourth phase shifter; 20. a matrix switch; 21. an input of the matrix switch; 211. a first input; 212. a second input terminal; 213. a third input; 214. a fourth input; 22. the output end of the matrix switch; 221. a first output terminal; 222. a second output terminal; 223. a third output; 224. a fourth output terminal; 30. an antenna; 31. a first antenna; 32. a second antenna; 40. a receiver chip; 41. a first receiver chip; 42. a second receiver chip; 43. a third receiver chip; 44. a fourth receiver chip; s1, a single-pole three-throw switch; s2, a first single-pole double-throw switch; s3, a single-pole four-throw switch; s4, a second single-pole double-throw switch; s5, a third single-pole double-throw switch; s6, a fourth single-pole double-throw switch; s7, a fifth single-pole double-throw switch; s8, a sixth single-pole double-throw switch; r1, a first resistor; r2, a second resistor; r3, a third resistor; r4, a fourth resistor.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the following detailed description of specific embodiments of the present application is given with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the application and are not limiting thereof.

In describing embodiments of the present application, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

In a more common existing implementation manner, the satellite navigation system is provided with three radio frequency front-end circuits for respectively receiving the multi-frequency signals of a single antenna, the single frequency signals of multiple antennas and the multi-frequency signals of multiple antennas so as to realize three different RTK positioning algorithms, namely a single antenna multi-frequency positioning algorithm, a multi-antenna single-frequency directional gesture measurement algorithm and a multi-antenna multi-frequency directional gesture measurement algorithm. But the three radio frequency front-end circuits have higher manufacturing cost and larger volume, and are not beneficial to popularization and use of the satellite navigation system. And when testing the performance of single-antenna multi-frequency positioning, multi-antenna single-frequency directional attitude measurement and multi-antenna multi-frequency directional attitude measurement of various receiver chips, the matched receiver chip is configured for each radio frequency front-end circuit, and the testing cost is higher.

In order to solve the above problems, the embodiment of the application provides a radio frequency front-end circuit, which ensures the excellent radio frequency performance of the radio frequency front-end and has lower manufacturing cost and smaller volume.

Fig. 1 is a schematic block diagram of a radio frequency front-end circuit according to an embodiment of the present application. As shown in fig. 1, the radio frequency front-end circuit comprises a frequency dividing circuit 10 and a matrix switch 20, the frequency dividing circuit 10 comprising at least two inputs 11 and at least four outputs 12, the matrix switch 20 comprising at least four inputs 21 and at least four outputs 22. The input end 11 of the frequency dividing circuit 10 is used for connecting the antenna 30, and each output end 12 of the frequency dividing circuit 10 is connected with each input end 21 of the matrix switch 20; each input end 21 of the matrix switch 20 is correspondingly connected with each output end 22 through a switching device, and the output end 22 of the matrix switch 20 is used for being connected with the receiver chip 40; wherein the plurality of switching devices within the matrix switch 20 are switched in at least three switching state combinations to cause the receiver chip 40 to respectively execute three RTK positioning algorithms in various switching state combinations.

In the present embodiment, antenna 30 is a receiving antenna supporting multi-band signals, including but not limited to a wideband antenna and a multi-band antenna. Each input end of the frequency dividing circuit 10 is correspondingly connected with an antenna 30, and when the antenna 30 receives the multi-band signals sent by the satellite, the received multi-band signals are transmitted to the input end of the frequency dividing circuit 10. The frequency dividing circuit 10 receives the multi-band signals transmitted by the antennas 30 from the respective input terminals 11, and divides each multi-band signal into two different single-band signals. Since different satellite systems correspond to different working frequency bands, for example, the working frequency bands of the Beidou satellite system include B1, B2 and B3, the working frequency bands of the global positioning system include L1, L2 and L5, and the frequency dividing function of the frequency dividing circuit 10 can be selected according to the working frequency band of the satellite navigation system. For example, when the operating frequency band of the satellite navigation system is B1, B2, and B3, the frequency dividing circuit 10 may divide the multi-band signal transmitted by the antenna 30 into a signal in the B1 frequency band and a signal in the B2/B3 frequency band, and when the operating frequency band of the satellite navigation system is L1, L2, and L5, the frequency dividing circuit 10 may divide the multi-band signal transmitted by the antenna 30 into a signal in the L1 frequency band and a signal in the L2/L5 frequency band. Wherein, the frequencies of the B2 frequency band and the B3 frequency band are similar, the default B2 frequency band and the B3 frequency band are the same single frequency band, the frequencies of the L2 frequency band and the L5 frequency band are similar, and the default L2 frequency band and the L5 frequency band are the same single frequency band. After the frequency division circuit 10 divides the multi-band signal transmitted by each antenna 30 into two single-band signals, the two single-band signals corresponding to each antenna 30 are respectively transmitted to the two output terminals 12 of the frequency division circuit 10, and one output terminal 12 of the frequency division circuit 10 receives only one single-band signal. The output terminals 12 of the frequency dividing circuit 10 are connected to the input terminals 21 of the matrix switch 20 one-to-one, and the output terminals 12 of the frequency dividing circuit 10 can correspondingly transmit the received single-band signals to the input terminals of the matrix switch 20 correspondingly connected, so that each input terminal 31 of the matrix switch 20 correspondingly receives two single-band signals from each antenna 30. The present embodiment describes the working frequency bands of the satellite navigation system as L1, L2 and L5.

The input 21 and the respective output 22 of the matrix switch 20 may be one-to-one, one-to-many and/or many-to-one connections. However, whatever the connection structure, the input 21 and the output 22 are alternatively connected or disconnected in various combinations of switch states. For example, one input 21 of the matrix switch 20 is connected to three outputs 22, but the input 21 may be connected to only one of the outputs 22 or not connected to any of the outputs 22. Likewise, one output 22 is connected to a plurality of outputs 21, which will also be in communication with only one of the inputs 21 or not with any of the inputs 21. A switching state combination is understood to mean a combination of the matrix switches when the individual switching devices are in the corresponding switching state.

The present embodiment is described taking the one-to-one connection of the input terminal 21 and the output terminal 22 as an example. The input terminal 21 and the corresponding connected output terminal 22 are connected through a switching device, and the closing or opening of the switching device between the input terminal 21 and the corresponding connected output terminal 22 can control whether the input terminal 21 and the corresponding connected output terminal 22 are in an on state or an off state. When the input end 21 of the matrix switch 20 and the corresponding connected output end 22 are in a conducting state, the single-band signal received by the input end 21 of the matrix switch 20 can be transmitted to the corresponding connected output end 22; when the input terminal 21 of the matrix switch 20 is in an off state with the corresponding output terminal 22, the single-band signal received by the input terminal 21 of the matrix switch 20 cannot be transmitted to the corresponding connected output terminal 22. The control unit of the electronic device or the satellite navigation system can control each switching device in the matrix switch to be kept in a corresponding switching state according to an RTK positioning algorithm to be executed by the receiver chip.

The receiver chip can execute three RTK positioning algorithms, namely a single-antenna multi-frequency positioning algorithm, a multi-antenna single-frequency directional gesture measurement algorithm and a multi-antenna multi-frequency directional gesture measurement algorithm. Wherein, in the first switch state combination of the matrix switch, signals of each frequency band of the single antenna are transmitted to the receiver chip, so that the receiver chip executes the single antenna multi-frequency positioning algorithm based on the received signals. For example, when the receiver chip is to perform a single antenna multi-frequency positioning algorithm, the rf front-end circuit may transmit the single-band signals of multiple bands received by the single antenna 30 to the receiver chip 40. At this time, the control unit may control the switch device between the input end 21 and the corresponding output end 22 of the matrix switch 20, which receives the single-band signals from the same antenna 30, to be closed, and the switch device between the other input ends 21 and the corresponding output ends 22 to be opened, so that the two output ends 22 of the matrix switch 20, which receive the single-band signals, respectively send the single-band signals from the same antenna 30 to the two receiver chips 40, which are correspondingly connected, to enable the receiver chip 40, which receives the signals, to accurately position the electronic device based on the single-band signals from the two different frequency bands of the antenna 30.

And under the condition that the matrix switch is in the second switch state combination, the signals of the same frequency band of each antenna are transmitted to the receiver chip, so that the receiver chip executes a multi-antenna single-frequency directional attitude measurement algorithm based on the received signals. For example, when the receiver chip is to perform the multi-antenna single-frequency directional gesture measurement algorithm, the rf front-end circuit may transmit the single-band signals of the same frequency band received by the multiple antennas 30 to the receiver chip 40. At this time, the control unit may control the switching devices between the input end 21 and the corresponding output end 22 of the matrix switch 20, which receive the single-band signals from the same frequency band of the different antennas 30, to be closed, and the switching devices between the other input ends 21 and the corresponding output ends 22 to be opened, so that each output end 22 of the matrix switch 20, which receives the single-band signals, respectively sends the single-band signals from the same frequency band of the multiple antennas 30 to each corresponding connected receiver chip 40, so that the receiver chip 40, which receives the signals, performs directional gesture measurement on the electronic device based on the single-band signals from the same frequency band of the multiple antennas 30.

And under the condition that the matrix switch is in the third switch state combination, signals of all frequency bands of all antennas are transmitted to the receiver chip, so that the receiver chip executes a multi-antenna multi-frequency orientation gesture measurement algorithm based on the received signals. For example, when the receiver chip is to perform the multi-antenna multi-frequency orientation gesture measurement algorithm, the rf front-end circuit may transmit the single-band signals of the multiple frequency bands received by the multiple antennas 30 to the receiver chip 40. At this time, the control unit may control all the switching devices in the matrix switch 20 to be turned on, so that all the output terminals 22 of the matrix switch 20 respectively send the single-band signals of two different frequency bands from the multiple antennas 30 to the corresponding connected receiver chips 40, so that the receiver chip 40 receiving the signals performs orientation measurement on the electronic device based on the single-band signals of two different frequency bands of the multiple antennas 30.

It should be noted that, although fig. 1 shows that the frequency dividing circuit 10 is connected to four antennas 30, it is not limited to connecting four antennas 30, and the number of antennas 30 connected to the frequency dividing circuit 10 may be set according to the actual requirement of the satellite navigation system, and the number of receiver chips 40 in the satellite navigation system is twice as many as the number of antennas 30, because each receiver chip 40 is used for receiving one single-band signal from one antenna 30. The number of receiver chips can be adaptively reduced if the receiver chips employed are provided with two inputs or more.

In an embodiment, fig. 2 is a schematic diagram of a frequency dividing circuit according to an embodiment of the application. As shown in fig. 2, the frequency dividing circuit 10 includes 2N splitters 13 and 4N filters 14, and the matrix switch 20 includes 4N inputs 21 and 4N outputs 22, N being a positive integer greater than or equal to 1. The input end of each splitter 13 is used for being correspondingly connected with an antenna 30, the input ends of each two filters 14 are correspondingly connected with the output end of one splitter 13, and each input end 21 of the matrix switch 20 is connected with the output end of one filter 14. The splitter 13 is configured to split a signal input by the corresponding antenna 30 into two signals and transmit the two signals to the corresponding connected filters 14, and the two filters 14 connected to the same splitter 13 are configured to filter signals in different frequency bands.

The input end of each splitter 13 in the frequency dividing circuit 10 is an input end of the frequency dividing circuit 10, and the output end of each filter 14 is an output end of the frequency dividing circuit 10, and accordingly, the frequency dividing circuit 10 includes 2N input ends and 4N output ends. The frequency divider circuit 10 may be connected to 2N antennas 30, and the matrix switch 20 may be connected to 4N receiver chips 40. For ease of understanding, the frequency dividing circuit 10 may be considered to include 2N frequency dividing circuits, each of which includes one splitter 13 and two filters 14, and is configured to divide a multi-band signal transmitted by the antenna 30 to which the splitter 13 is correspondingly connected into two single-band signals having different frequency bands. In a frequency division sub-circuit, the splitter 13 splits the multi-band signal received by the corresponding connected antenna 30 into two multi-band signals, and transmits the two multi-band signals to the two filters 14 correspondingly connected. Assuming that the current satellite navigation system operates in the L1, L2, and L5 frequency bands, one filter 14 in the frequency divider circuit is a SAW (surface acoustic wave) filter supporting the L1 frequency band and has a good suppression effect on signals other than the L1 frequency band, and the other filter 14 is a SAW filter supporting the L2/L5 frequency band and has a good suppression effect on signals other than the L2/L5 frequency band. The SAW filter supporting the L1 frequency band carries out filtering processing on the received multi-frequency band signals, outputs signals of the L1 frequency band, carries out filtering processing on the received multi-frequency signals by the SAW filter supporting the L1 frequency band, and outputs signals of the L2/L5 frequency band. Each frequency division sub-circuit has the same structure, and can divide the multi-frequency band signal received by the corresponding connected antenna 30 into a signal in the L1 frequency band and a signal in the L2/L5 frequency band, so that each input end of the matrix switch 20 can receive the signal in the L1 frequency band and the signal in the L2/L5 frequency band received by the corresponding connected antenna 30 of each frequency division sub-circuit.

In this embodiment, splitter 13 may be a wideband power splitter or a diplexer having an operating bandwidth covering the operating frequency band of the satellite navigation system, including, but not limited to, a patch set power splitter and a wilkinson power splitter. For example, when the operating frequency band of the satellite navigation system is L1, L2, L5 frequency band, the splitter 13 may cover the L1, L2, L5 frequency band with an operating bandwidth.

In order to reduce the manufacturing cost and the operating power consumption of the satellite navigation system, the satellite navigation system is provided with two antennas 30 for receiving signals issued by satellites and four receiver chips 40 for processing the signals. Correspondingly, when the satellite navigation system is provided with two antennas 30 and four receiver chips 40, the frequency dividing circuit 10 is provided with two splitters 13 and four filters 14 to divide the signals transmitted by the antennas 30, and the matrix switch 20 is provided with four input ends 21 and four output ends 22 to transmit the signals transmitted by the frequency dividing circuit 10 to the receiver chips 40 according to the working mode of the satellite navigation system. In this embodiment, fig. 3 is a schematic structural diagram of a radio frequency front-end circuit according to an embodiment of the present application. As shown in fig. 3, the frequency dividing circuit 10 includes a first splitter 131, a second splitter 132, a first filter 141, a second filter 142, a third filter 143, and a fourth filter 144, and the matrix switch 20 includes four input terminals 21 and four output terminals 22. The input end of the first splitter 131 is used for being connected with the first antenna 31, and the output end of the first splitter 131 is connected with the input end of the first filter 141 and the input end of the second filter 142; the input end of the second splitter 132 is used for connecting the second antenna 32, and the output end of the second splitter 132 is connected with the input end of the third filter 143 and the input end of the fourth filter 144; the four input terminals 21 of the matrix switch 20 are respectively connected to the output terminal of the first filter 141, the output terminal of the second filter 142, the output terminal of the third filter 143 and the output terminal of the fourth filter 144, and the four output terminals 22 of the matrix switch 20 are respectively connected to the first receiver chip 41, the second receiver chip 42, the third receiver chip 43 and the fourth receiver chip 44; the first filter 141 and the third filter 143 are used for signals outside the first frequency band, and the second filter 142 and the fourth filter 144 are used for filtering signals outside the second frequency band.

In this embodiment, the first frequency band is an L1 frequency band, and the second frequency band is an L2/L5 frequency band. The first filter 141 and the third filter 143 are SAW filters supporting the L1 band, and the second filter 142 and the fourth filter 144 are SAW filters supporting the L2/L5 band, as an example. The first antenna 31 transmits the received multi-band signal to the first splitter 131, the first splitter 131 splits the multi-band signal into two paths, one path of multi-band signal is transmitted to the first filter 141, and the other path of multi-band signal is transmitted to the second filter 142. The first filter 141 filters signals of frequency bands other than the L1 band among the received multi-band signals, and outputs signals of the L1 band. The second filter 142 filters signals of frequency bands other than the L2/L5 band among the received multi-band signals, and outputs signals of the L2/L5 band. The second antenna 32 transmits the received multi-band signal to the second splitter 132, the second splitter 132 splits the multi-band signal into two paths, one path of multi-band signal is transmitted to the third filter 143, and the other path of multi-band signal is transmitted to the fourth filter 144. The third filter 143 filters signals of frequency bands other than the L1 band among the received multi-band signals, and outputs signals of the L1 band. The fourth filter 144 filters signals of frequency bands other than the L2/L5 band among the received multi-band signals, and outputs signals of the L2/L5 band.

Further, the four inputs 21 of the matrix switch 20 include a first input 211, a second input 212, a third input 213 and a fourth input 214, and the four outputs 22 of the matrix switch 20 include a first output 221, a second output 222, a third output 223 and a fourth output 224. The output of the first filter 141, the output of the second filter 142, the output of the third filter 144 and the output of the fourth filter 144 are respectively connected to the first input 211, the second input 212, the third input 213 and the fourth input 214 of the matrix switch 20.

In the case of the one-to-one connection structure of the input terminals 21 and the output terminals 22 of the matrix switch 20, the first input terminal 211 is connected to the first output terminal 221 through a first switching device, the second input terminal 212 is connected to the second output terminal 222 through a second switching device, the third input terminal 213 is connected to the third output terminal 223 through a third switching device, and the fourth input terminal 214 is connected to the fourth output terminal 224 through a fourth switching device. The first output 221, the second output 222, the third output 223, and the fourth output 224 of the matrix switch 20 are connected to the first receiver chip 41, the second receiver chip 42, the third receiver chip 43, and the fourth receiver chip 44, respectively. The first filter 141 feeds the L1 band signal from the first antenna 31 to the first input 211, the second filter 142 feeds the L2/L5 band signal from the first antenna 31 to the second input 212, the third filter 143 feeds the L1 band signal from the second antenna 32 to the third input 213, and the fourth filter 144 feeds the L2/L5 band signal from the second antenna 32 to the fourth input 214.

In this embodiment, the first switch state combination may be that the first and second switching devices are closed, and the third and fourth switching devices are opened, and at this time, the first and second input terminals 211 and 212 transmit the signals of the L1 band and the signals of the L2/L5 band from the first antenna 31 to the first and second receiver chips 41 and 42, respectively, and the first and second receiver chips 41 and 42 may perform a single antenna multi-frequency location algorithm based on the received signals of the L1 band and the signals of the L2/L5 band of the first antenna 31. Alternatively, the first switch state combination may also be that the first switch device and the second switch device are opened, and the third switch device and the fourth switch device are closed, and at this time, the third input terminal 213 and the fourth input terminal 214 transmit the signal in the L1 band and the signal in the L2/L5 band from the second antenna 32 to the third receiver chip 43 and the fourth receiver chip 44, respectively, and the third receiver chip 43 and the fourth receiver chip 44 may perform a single antenna positioning algorithm based on the received signal in the L1 band and the received signal in the L2/L5 band of the second antenna 32.

The second switch state combination may be that the first and third switching devices are closed, and the second and fourth switching devices are opened, when the first and third input terminals 211 and 213 transmit signals of the L1 frequency band from the first and second antennas 31 and 32 to the first and third receiver chips 41 and 43, respectively, and the first and third receiver chips 41 and 43 may perform a multi-antenna single frequency orientation gesture measurement algorithm based on the received signals of the L1 frequency band from the first and second antennas 31 and 32. Alternatively, the second switch state combination may be that the first switch device and the third switch device are opened, and the second switch device and the fourth switch device are closed, and the second input terminal 212 and the fourth input terminal 214 transmit signals of the L2/L5 frequency band from the first antenna 31 and the second antenna 32 to the second receiver chip 42 and the fourth receiver chip 44, respectively, and the second receiver chip 42 and the fourth receiver chip 44 may perform a multi-antenna single frequency orientation gesture measurement algorithm based on the signals of the L2/L5 frequency band from the first antenna 31 and the second antenna 32.

The third switch state combination may be that the first, second, third and fourth switch devices are closed, and at this time, the first, second, third and fourth input terminals 211, 212, 213 and 214 transmit the signals of the L1 band and the signals of the L2/L5 band from the first antenna 31 and the signals of the L1 band and the signals of the L2/L5 band from the second antenna 32 to the first, second, third and fourth receiver chips 41, 42, 43 and 44, respectively, such that the first, second, third and fourth receiver chips 41, 42, 43 and 44 perform a multi-antenna multi-frequency orientation gesture measurement algorithm based on the received signals.

In the case where the input terminals 21 and the output terminals 22 of the matrix switch 20 include a one-to-one, one-to-many, and many-to-one connection structure, the first input terminal 211 is connected to the first output terminal 221 and the third output terminal 223, the second input terminal 212 is connected to the second output terminal 222, the third input terminal 213 is connected to the second output terminal 222, the third output terminal 223, or the fourth output terminal 224, and the fourth input terminal 214 is connected to the fourth output terminal 224.

In this embodiment, when the matrix switch is in the first switch state combination, the first input terminal 211 is connected to the first output terminal 221, the second input terminal 212 is connected to the second output terminal 222, the third input terminal 213 is not connected to the second output terminal 222, the third output terminal 223 and the fourth output terminal 224, the fourth input terminal 214 is not connected to the fourth output terminal 224, the first input terminal 211 and the second input terminal 212 transmit the signal of the L1 band and the signal of the L2/L5 band from the first antenna 31 to the first receiver chip 41 and the second receiver chip 42, respectively, and the first receiver chip 41 and the second receiver chip 42 may perform a single antenna multi-frequency positioning algorithm based on the signal of the L1 band and the signal of the L2/L5 band of the first antenna 31. Alternatively, when the matrix switch is in the first switch state combination, the first input terminal 211 is not connected to the first output terminal 221 and the second output terminal 222, the second input terminal 212 is not connected to the second output terminal 222, the third input terminal 213 is connected to the third output terminal 223, the fourth input terminal 214 is connected to the fourth output terminal 224, the third input terminal 213 and the fourth input terminal 214 transmit the signal of the L1 band and the signal of the L2/L5 band from the second antenna 32 to the third receiver chip 43 and the fourth receiver chip 44, respectively, and the third receiver chip 43 and the fourth receiver chip 44 may perform the single antenna multi-frequency positioning algorithm based on the signal of the L1 band and the signal of the L2/L5 band of the second antenna 32.

When the matrix switch is in the second switch state combination, the first input terminal 211 is communicated with the first output terminal 221, the second input terminal 212 is not communicated with the second output terminal 222, the third input terminal 213 is communicated with the second output terminal 222, the fourth input terminal 214 is not communicated with the fourth output terminal 224, the first input terminal 211 and the third input terminal 213 respectively transmit signals of the L1 frequency band from the first antenna 31 and the second antenna 32 to the first receiver chip 41 and the second receiver chip 42, and the first receiver chip 41 and the second receiver chip 42 execute a multi-antenna single-frequency orientation gesture measurement algorithm based on the signals of the L1 frequency band of the first antenna 31 and the second antenna 32. Alternatively, when the matrix switch is in the second switch state combination, the first input 211 is connected to the third output 223, the second input 212 is not connected to the second output 222, the third input 213 is connected to the fourth output 224, the fourth input 214 is not connected to the fourth output 224, the second input 212 and the fourth input 214 transmit the signals of the L2/L5 band from the first antenna 31 and the second antenna 32 to the third receiver chip 43 and the fourth receiver chip 44, respectively, and the third receiver chip 43 and the fourth receiver chip 44 may perform the multi-antenna single-frequency orientation gesture measurement algorithm based on the signals of the L2/L5 band of the first antenna 31 and the second antenna 32.

When the matrix switch is in the third switch state combination, the first input end 211 is communicated with the first output end 221, the second input end 212 is communicated with the second output end 222, the third input end 213 is communicated with the third output end 223, the fourth input end 214 is communicated with the fourth output end 224, the first input end 211, the second input end 212, the third input end 213 and the fourth input end 214 respectively transmit signals of the L1 frequency band and signals of the L2/L5 frequency band from the first antenna 31 and signals of the L1 frequency band and signals of the L2/L5 frequency band from the second antenna 32 to the first receiver chip 41, the second receiver chip 42, the third receiver chip 43 and the fourth receiver chip 44, and the first receiver chip 41, the second receiver chip 42, the third receiver chip 43 and the fourth receiver chip 44 can perform a multi-antenna multi-frequency orientation and attitude measurement algorithm based on the received signals.

As can be seen from the above, the matrix switch has two first switch state combinations, and the single antenna multi-frequency positioning algorithm is executed by different receiver chips under different first switch state combinations; the matrix switch has two second switch state combinations, and the multi-antenna single-frequency positioning algorithm is executed by different receiver chips under different second switch state combinations. Therefore, the present embodiment proposes that, when testing the operation performance of the receiver chips, the first receiver chip 41 and the second receiver chip 42 can be configured as the first type of receiver chip, and the third receiver chip and the fourth receiver chip can be configured as the second type of receiver chip, so as to compare the performance of the two types of receiver chips in the operation modes of single-antenna multi-frequency positioning and multi-antenna single-frequency directional gesture measurement.

In this embodiment, in the case that the matrix switch is in the first switch state combination, signals of the first frequency band and the second frequency band of the first antenna are transmitted to the first receiver chip and the second receiver chip, respectively, so that the first receiver chip and the second receiver chip execute a single-antenna multi-frequency positioning algorithm based on the received signals to obtain a first positioning result; the signals of the first frequency band and the second frequency band of the second antenna are respectively transmitted to a third receiver chip and a fourth receiver chip, so that the third receiver chip and the fourth receiver chip execute a single-antenna multi-frequency positioning algorithm based on the received signals to obtain a second positioning result; the first positioning result and the second positioning result are used to test the positioning performance of the first type of receiver chip and the second type of receiver chip.

Illustratively, in a first switch state combination, the first input 211 is connected to the first output 221, the second input 212 is connected to the second output 222, the first receiver chip 41 and the second receiver chip 42 receive signals from the L1 band and the L2/L5 band of the first antenna 31, respectively, and the first receiver chip 41 and the second receiver chip 42 perform a single antenna multi-frequency positioning algorithm based on the signals from the L1 band and the L2/L5 band of the first antenna 31 to obtain a first positioning result. In another first switch state combination, the third input terminal 213 is connected to the third output terminal 223, the fourth input terminal 214 is connected to the fourth output terminal 224, the third receiver chip 43 and the fourth receiver chip 43 respectively receive signals of the L1 band and the L2/L5 band from the second antenna 32, and the third receiver chip 43 and the fourth receiver chip 44 execute a single antenna multi-frequency positioning algorithm based on the signals of the L1 band and the L2/L5 band of the second antenna 32 to obtain a second positioning result. The first positioning result may be compared with the second positioning result to analyze multi-antenna single frequency positioning performance of the receiver chips of the first type and the second type.

In the embodiment, under the condition that the matrix switch is in a second switch state combination, signals of a first frequency band of the first antenna and signals of a first frequency band of the second antenna are respectively transmitted to the first receiver chip and the second receiver chip, so that the first receiver chip and the second receiver chip execute a multi-antenna single-frequency positioning algorithm based on the received signals to obtain a first orientation gesture measurement result; the signals of the first frequency bands of the first antenna and the second antenna are respectively transmitted to a third receiver chip and a fourth receiver chip, so that the third receiver chip and the fourth receiver chip execute a multi-antenna single-frequency positioning algorithm based on the received signals to obtain a second orientation gesture measurement result; the first orientation gesture measurement result and the second orientation gesture measurement result are used for testing the orientation gesture measurement performance of the first type of receiver chip and the second type of receiver chip.

For example, in a second switch state combination, the first input terminal 211 is connected to the first output terminal 221, the third input terminal 213 is connected to the second output terminal 222, the first receiver chip 41 and the second receiver chip 42 receive signals in the L1 frequency band from the first antenna 31 and the second antenna 32, and the first receiver chip 41 and the second receiver chip 42 execute a multi-antenna single-frequency directional gesture measurement algorithm based on the signals in the L1 frequency band from the first antenna 31 and the second antenna 32 to obtain a first directional gesture measurement result. The first input end 211 is connected to the third output end 223, the third input end 213 is connected to the fourth output end 224, the third receiver chip 43 and the fourth receiver chip 44 receive signals of the L1 frequency band from the first antenna 31 and the second antenna 32, and the third receiver chip 43 and the fourth receiver chip 44 execute a multi-antenna single-frequency orientation gesture measurement algorithm based on the signals of the L1 frequency band from the first antenna 31 and the second antenna 32 to obtain a second orientation gesture measurement result. The first orientation gesture measurement result and the first orientation gesture measurement result can be compared, and the multi-antenna single-frequency orientation gesture measurement performance of the receiver chips of the first type and the second type can be analyzed.

In an embodiment, fig. 4 is a schematic structural diagram of a matrix switch according to an embodiment of the present application. As shown in fig. 4, the matrix switch 20 includes a first single pole double throw switch S2, a second single pole double throw switch S4, a third single pole double throw switch S5, a fourth single pole double throw switch S6, a fifth single pole double throw switch S7, a sixth single pole double throw switch S8, a single pole triple throw switch S1, and a single pole four throw switch S3. The main wiring point of the single-pole three-throw switch S1 is connected with the first input end 211, the three movable wiring points of the single-pole three-throw switch S1 are respectively connected with the first movable wiring point of the third single-pole two-throw switch S5, the first movable wiring point of the fifth single-pole two-throw switch S7 and the ground, the main wiring point of the third single-pole two-throw switch S5 is connected with the first output end 221, the main wiring point of the fifth single-pole two-throw switch S7 is connected with the third output end 223, the main connection point of the first single-pole two-throw switch S2 is connected with the second input end 212, the two movable wiring points of the first single-pole two-throw switch S2 are respectively connected with the first movable wiring point of the fourth single-pole two-throw switch S6 and the ground, the main connection point of the fourth single-pole two-throw switch S6 is connected with the second output end 222, the main connection point of the fourth single-pole four-throw switch S3 is connected with the third input end 213, the four movable connection point of the single-pole four-throw switch S3 is respectively connected with the second movable wiring point of the fourth single-pole two-throw switch S6, the second single-throw switch S7 is connected with the second movable wiring point of the fourth single-throw two-throw switch S8, and the second single-throw two-throw wiring point of the second single-throw switch S8 is connected with the second single-throw wiring point 8. In this embodiment, the movable connection point of the single-pole three-throw switch S1, the movable connection point of the first single-pole double-throw switch S2, the movable connection point of the single-pole four-throw switch S3, and the movable connection point of the second single-pole double-throw switch S4 are respectively connected to ground through resistors. The resistance of the resistor can be set according to practical situations, and is generally set to be 50 ohms.

In this embodiment, the first switch state combination may be that the first input terminal 211 communicates with the first output terminal 221 through the single pole three throw switch S1 and the third single pole double throw switch S5, and the second input terminal 212 communicates with the second output terminal 222 through the second single pole double throw switch S4 and the fourth single pole double throw switch S6. Alternatively, the first switch state combination may further include a third input terminal 213 connected to the third output terminal 223 through a single pole four throw switch S3 and a fifth single pole double throw switch S7, and a fourth input terminal 214 connected to the fourth output terminal 224 through a second single pole double throw switch S4 and a sixth single pole double throw switch S8.

Fig. 5 is a first schematic diagram of a first switch state combination according to an embodiment of the present application. As shown in fig. 5, the main junction of the single-pole three-throw switch S1 is connected to the first movable junction of the single-pole three-throw switch S1, the main junction of the third single-pole double-throw switch S5 is connected to the first movable junction of the third single-pole double-throw switch S5, and the first input end 211 is connected to the first output end 221 at this time, because the first movable junction of the single-pole three-throw switch S1 is connected to the first movable junction of the third single-pole double-throw switch S5. The main junction of the first single-pole double-throw switch S2 is connected to the first movable junction of the first single-pole double-throw switch S2, and the main junction of the fourth single-pole double-throw switch S6 is connected to the first movable junction of the fourth single-pole double-throw switch S6, so that the second input end 212 is connected to the second output end 222. The first receiver chip 41 and the second receiver chip 42 acquire signals of the L1 band and the L2/L5 band from the first antenna 31 through the first output terminal 221 and the second output terminal 222, respectively, and can perform positioning based on the signals of the L1 band and the L2/L5 band of the first antenna 31. Meanwhile, the main junction point of the single-pole four-throw switch S3 is connected to the fourth movable junction point of the single-pole four-throw switch S3, and the third input end 213 is grounded due to the fact that the fourth movable junction point of the single-pole four-throw switch S3 is grounded through the third resistor R3, and the third resistor R3 can absorb the load of the third input end 213. The main junction of the second single-pole double-throw switch S4 is connected to the second movable junction of the second single-pole double-throw switch S4, and the fourth input terminal 214 is grounded due to the fact that the second movable junction of the second single-pole double-throw switch S4 is grounded through the fourth resistor R4, and the fourth resistor R4 can absorb the load of the fourth input terminal 214. The third resistor R3 and the fourth resistor R4 absorb loads to solve the problem of power reflection, and stability of the satellite navigation system is greatly improved.

Fig. 6 is a second schematic diagram of the first switch state combination according to the embodiment of the present application. As shown in fig. 6, the main junction of the single-pole four-throw switch S3 is connected to the second movable junction of the single-pole four-throw switch S3, and the main junction of the fifth single-pole double-throw switch S7 is connected to the second movable junction of the fifth single-pole double-throw switch S7, so that the third input end 213 is connected to the third output end 223. The main junction of the second single-pole double-throw switch S4 is connected to the first movable junction of the second single-pole double-throw switch S4, and the main junction of the sixth single-pole double-throw switch S8 is connected to the second movable junction of the sixth single-pole double-throw switch S8, so that the fourth input terminal 214 is connected to the fourth output terminal 224. The third receiver chip 43 and the fourth receiver chip 44 acquire signals of the L1 band and the L2/L5 band from the second antenna 32 through the third output terminal 223 and the fourth output terminal 224, respectively, and can perform positioning based on the signals of the L1 band and the L2/L5 band of the second antenna 32. Meanwhile, the main junction point of the single-pole three-throw switch S1 is connected to the third active junction point of the single-pole three-throw switch S1, and the first input end 211 is grounded due to the fact that the third active junction point of the single-pole three-throw switch S1 is grounded through the first resistor R1, and the first resistor R1 can absorb the load of the first input end 211. The main junction point of the first single-pole double-throw switch S2 is connected to the second movable junction point of the first single-pole double-throw switch S2, and the second movable junction point of the first single-pole double-throw switch S2 is grounded through the second resistor R2, so that the second input end 212 is grounded, and the second resistor R2 can absorb the load of the second input end 212. The first resistor R1 and the second resistor R2 absorb loads to solve the problem of power reflection, and stability of the satellite navigation system is greatly improved.

In this embodiment, the second switch state combination may be that the first input terminal 211 communicates with the first output terminal 221 through the single pole three throw switch S1 and the third single pole double throw switch S5, and the third input terminal 213 communicates with the second output terminal 222 through the single pole four throw switch S3 and the fourth single pole double throw switch S6. Alternatively, the second switch state combination may also be that the first input terminal 211 is connected to the third output terminal 223 through the single pole three throw switch S1 and the fifth single pole double throw switch S7, and the third input terminal 213 is connected to the fourth output terminal 224 through the single pole four throw switch S3 and the sixth single pole double throw switch S8.

Fig. 7 is a first schematic diagram of a second switch state combination according to an embodiment of the present application. As shown in fig. 7, the main junction of the single-pole three-throw switch S1 is connected to the first movable junction of the single-pole three-throw switch S1, the main junction of the third single-pole double-throw switch S5 is connected to the first movable junction of the third single-pole double-throw switch S5, and the first input end 211 is connected to the first output end 221 at this time, because the first movable junction of the single-pole three-throw switch S1 is connected to the first movable junction of the third single-pole double-throw switch S5. The main junction of the single-pole four-throw switch S3 is connected to the first movable junction of the single-pole four-throw switch S3, and the main junction of the fourth single-pole double-throw switch S6 is connected to the second movable junction of the fourth single-pole double-throw switch S6, so that the first movable junction of the single-pole four-throw switch S3 is connected to the second movable junction of the fourth single-pole double-throw switch S6, and at this time, the third input end 213 is connected to the second output end 222. The first receiver chip 41 and the second receiver chip 42 acquire signals of the L1 frequency band from the first antenna 31 and the second antenna 32 through the first output end 221 and the second output end 222, respectively, and can perform orientation measurement based on the signals of the L1 frequency band of the first antenna 31 and the second antenna 32. Meanwhile, the main junction point of the first single-pole double-throw switch S2 is connected to the second movable junction point of the first single-pole double-throw switch S2, and the second movable junction point of the first single-pole double-throw switch S2 is grounded through the second resistor R2, so that the second input end 212 is grounded, and the second resistor R2 can absorb the load of the second input end 212. The main junction of the second single-pole double-throw switch S4 is connected to the second movable junction of the second single-pole double-throw switch S4, and the fourth input terminal 214 is grounded due to the fact that the second movable junction of the second single-pole double-throw switch S4 is grounded through the fourth resistor R4, and the fourth resistor R4 can absorb the load of the fourth input terminal 214. The second resistor R2 and the fourth resistor R4 absorb loads to solve the problem of power reflection, and stability of the satellite navigation system is greatly improved.

Fig. 8 is a second schematic diagram of a second switch state combination according to an embodiment of the present application. As shown in fig. 8, the main junction of the single-pole three-throw switch S1 is connected to the second movable junction of the single-pole three-throw switch S1, the main junction of the fifth single-pole double-throw switch S7 is connected to the first movable junction of the fifth single-pole double-throw switch S7, and the first input end 211 is connected to the third output end 223 at this time, because the second movable junction of the single-pole three-throw switch S1 is connected to the first movable junction of the fifth single-pole double-throw switch S7. The main junction of the single-pole four-throw switch S3 is connected to the third movable junction of the single-pole four-throw switch S3, and the main junction of the sixth single-pole double-throw switch S8 is connected to the first movable junction of the sixth single-pole double-throw switch S8, so that the third input terminal 213 is connected to the fourth output terminal 224. The third receiver chip 43 and the fourth receiver chip 44 acquire signals of the L1 frequency band from the first antenna 31 and the second antenna 32 through the third output terminal 223 and the fourth output terminal 224, respectively, and may perform directional pose measurement based on the signals of the L1 frequency band of the first antenna 31 and the second antenna 32. Meanwhile, the main junction point of the first single-pole double-throw switch S2 is connected to the second movable junction point of the first single-pole double-throw switch S2, and the second movable junction point of the first single-pole double-throw switch S2 is grounded through the second resistor R2, so that the second input end 212 is grounded, and the second resistor R2 can absorb the load of the second input end 212. The main junction of the second single-pole double-throw switch S4 is connected to the second movable junction of the second single-pole double-throw switch S4, and the fourth input terminal 214 is grounded due to the fact that the second movable junction of the second single-pole double-throw switch S4 is grounded through the fourth resistor R4, and the fourth resistor R4 can absorb the load of the fourth input terminal 214. The second resistor R2 and the fourth resistor R4 absorb loads to solve the problem of power reflection, and stability of the satellite navigation system is greatly improved.

In this embodiment, the third switch state combination may be that the first input terminal 211 communicates with the first output terminal 221 through the single pole three throw switch S1 and the third single pole double throw switch S5, the second input terminal 212 communicates with the second output terminal 222 through the second single pole double throw switch S4 and the fourth single pole double throw switch S6, the third input terminal 213 communicates with the third output terminal 223 through the single pole four throw switch S3 and the fifth single pole double throw switch S7, and the fourth input terminal 214 communicates with the fourth output terminal 224 through the second single pole double throw switch S4 and the sixth single pole double throw switch S8.

Fig. 9 is a schematic diagram of a third switch state combination according to an embodiment of the present application. As shown in fig. 9, the main junction of the single-pole three-throw switch S1 is connected to the first movable junction of the single-pole three-throw switch S1, the main junction of the third single-pole double-throw switch S5 is connected to the first movable junction of the third single-pole double-throw switch S5, and the first input end 211 is connected to the first output end 221 at this time, because the first movable junction of the single-pole three-throw switch S1 is connected to the first movable junction of the third single-pole double-throw switch S5. The main junction of the first single-pole double-throw switch S2 is connected to the first movable junction of the first single-pole double-throw switch S2, and the main junction of the fourth single-pole double-throw switch S6 is connected to the first movable junction of the fourth single-pole double-throw switch S6, so that the second input end 212 is connected to the second output end 222. The main junction of the single-pole four-throw switch S3 is connected to the second movable junction of the single-pole four-throw switch S3, and the main junction of the fifth single-pole double-throw switch S7 is connected to the second movable junction of the fifth single-pole double-throw switch S7, so that the second movable junction of the single-pole four-throw switch S3 is connected to the second movable junction of the fifth single-pole double-throw switch S7, and at this time, the third input end 213 is connected to the third output end 223. The main junction of the second single-pole double-throw switch S4 is connected to the first movable junction of the second single-pole double-throw switch S4, and the main junction of the sixth single-pole double-throw switch S8 is connected to the second movable junction of the sixth single-pole double-throw switch S8, so that the fourth input terminal 214 is connected to the fourth output terminal 224. The first receiver chip 41, the second receiver chip 42, the third receiver chip 43 and the fourth receiver chip 44 acquire signals of the L1 frequency band and the L2/L5 frequency band from the first antenna 31 and the second antenna 32 through the first output end 221, the second output end 222, the third output end 223 and the fourth output end 224, respectively, and directional gesture measurement can be performed based on the signals of the L1 frequency band and the L2/L5 frequency band of the first antenna 31 and the second antenna 32.

Further, the second movable connection point of the third single-pole double-throw switch S5 is connected to the radio frequency test interface, and the receiver chip in the satellite navigation system can be debugged through the second movable connection point of the third single-pole double-throw switch S5.

It should be noted that, in the foregoing embodiments, the embodiment in which the satellite navigation system performs multi-antenna single-frequency directional attitude measurement based on the signals in the L1 frequency band of the first antenna and the second antenna is shown, if it is desired to simultaneously implement multi-antenna single-frequency directional attitude measurement based on the signals in the L2/L5 frequency band of the first antenna and the second antenna, the first single-pole double-throw switch S2 may be replaced by a single-pole four-throw switch S3, the second single-pole double-throw switch S4, the third single-pole double-throw switch S5, the fourth single-pole double-throw switch S6 and the fifth single-pole double-throw switch S7 may be replaced by a single-pole three-throw switch S1, so as to increase the connection paths between the second input end 212 and the first output end 221 and the third output end 223, and increase the connection paths between the fourth input end 214 and the second output end 222. Fig. 10 is a schematic structural diagram of another matrix switch according to an embodiment of the present application. As shown in fig. 10, the second input terminal 212 is connected to the first output terminal 221, the second output terminal 222, the third output terminal 223, or the ground, and the fourth input terminal 214 is connected to the second output terminal 222, the fourth output terminal 224, or the ground. When the second input 212 is connected to the first output 221 and the fourth input 214 is connected to the second output 222, the first receiver chip 41 and the second receiver chip 42 can receive signals in the L2/L5 band from the first antenna 31 and the second antenna 32. When the second input 212 is connected to the third output 223 and the fourth input 214 is connected to the fourth output 224, the third receiver chip 43 and the fourth receiver chip 44 can receive signals in the L2/L5 band from the first antenna 31 and the second antenna 32.

In one embodiment, the frequency dividing circuit 10 further includes 2N low noise amplifiers, and an input terminal of each splitter is correspondingly connected to an output terminal of one low noise amplifier, and an input terminal of each low noise amplifier is used for being connected to an antenna. The low noise amplifier is a broadband low noise amplifier chip supporting the working frequency band of the satellite navigation system, and the peripheral circuit of the broadband low noise amplifier chip is matched with the working frequency band so as to be suitable for the working frequency band of the satellite navigation system. The present embodiment is described taking an example in which the frequency dividing circuit 10 is provided with 2 low noise amplifiers. Referring to fig. 3, the frequency dividing circuit 10 includes a first low noise amplifier 151 and a second low noise amplifier 152, an input terminal of the first low noise amplifier 151 is connected to the first antenna 31, and an output terminal of the first low noise amplifier 151 is connected to an input terminal of the first splitter 131. An input terminal of the second low noise amplifier 152 is connected to the second antenna 32, and an output terminal of the second low noise amplifier 152 is connected to an input terminal of the second splitter 132. The first low noise amplifier 151 and the second low noise amplifier 152 amplify the signals received by the first antenna 31 and the second antenna 32, reduce noise of the signals, and improve the signal-to-noise ratio of output, so as to ensure that the signal links of the first antenna 31 and the second antenna 32 have good noise systems, and improve the noise performance of the whole radio frequency front-end circuit.

In one embodiment, the frequency divider circuit 10 includes 4N adjustable attenuators, each of which has an input terminal connected to the output terminal of one of the filters 14, and each of the input terminals 21 of the matrix switch 20 is connected to the output terminal of one of the adjustable attenuators. The adjustable attenuator can be an analog adjustable attenuator, a digital adjustable attenuator or a low-cost pi-shaped or T-shaped resistance attenuation network. Since the amplitude performance of devices such as a low noise amplifier and a splitter in different operating frequency bands is not uniform, for example, the gain and insertion loss of the L1 frequency band and the L2/L5 frequency band are not uniform, in the case that the number of devices on the signal link is large, the accumulation of the amplitude differences may seriously affect the amplitude balance of the signal finally entering the receiver chip 40. The introduction of the adjustable attenuator can ensure the amplitude balance of each signal link, the amplitude flatness of the signal links is stable in a smaller range, and the amplitude flatness of the signal links can be maintained within 1 db. This embodiment is described taking the case where the frequency dividing circuit 10 is provided with four adjustable attenuators as an example. Referring to fig. 3, the frequency dividing circuit 10 includes a first adjustable attenuator 161, a second adjustable attenuator 162, a third adjustable attenuator 163, and a fourth adjustable attenuator 164, wherein an input end of the first adjustable attenuator 161 is connected to an output end of the first filter 141, an input end of the second adjustable attenuator 162 is connected to an output end of the second filter 142, an input end of the third adjustable attenuator 163 is connected to an output end of the third filter 143, and an input end of the fourth adjustable attenuator 164 is connected to an output end of the fourth filter 144; the first input 211, the second input 212, the third input 213 and the fourth input 214 of the matrix switch 20 are connected to the output of the first adjustable attenuator 161, the output of the second adjustable attenuator 162, the output of the third adjustable attenuator 163 and the output of the fourth adjustable attenuator 164, respectively. The first, second, third and fourth adjustable attenuators 161, 162, 163 and 164 may adjust the amplitudes of the signals output from the first, second, third and fourth filters 141, 142, 143 and 144 so that the amplitudes of the signals received at the first, second, third and fourth inputs 211, 212, 213 and 214 may be stabilized within a certain range.

In one embodiment, the frequency dividing circuit 10 includes 4N variable gain amplifiers, each of which has an input terminal connected to the output terminal of one of the filters 14, and each of the input terminals 21 of the matrix switch 20 is connected to the output terminal of one of the variable gain amplifiers. The variable gain amplifier includes an amplifier with bypass (bypass) function, an analog variable gain amplifier, and a digital variable gain amplifier, and the variable gain amplifier can adjust the gain of the frequency dividing circuit 10 so that the radio frequency front end circuit is suitable for various external antennas 30. For example, when the antenna 30 gain is too large, the bypass function of the amplifier may be used or the gain of the variable gain amplifier may be reduced; when the gain of the antenna 30 is smaller, the amplifier can be turned on or the gain of the variable gain amplifier can be increased, so that the satellite navigation system can use various external antennas, the limitation of the gain range of the external antennas is avoided, and the dynamic range of the satellite navigation system is improved. The present embodiment is described taking the example in which the frequency dividing circuit 10 is provided with four variable gain amplifiers. Referring to fig. 3, the frequency dividing circuit 10 includes a first variable gain amplifier 171, a second variable gain amplifier 172, a third variable gain amplifier 173, and a fourth variable gain amplifier 174, an input terminal of the first variable gain amplifier 171 being connected to an output terminal of the first filter 141, an input terminal of the second variable gain amplifier 172 being connected to an output terminal of the second filter 142, an input terminal of the third variable gain amplifier 173 being connected to an output terminal of the third filter 143, an input terminal of the fourth variable gain amplifier 174 being connected to an output terminal of the fourth filter 144; the first input 211, the second input 212, the third input 213 and the fourth input 214 of the matrix switch 20 are connected to the output of the first variable gain amplifier 171, the output of the second variable gain amplifier 172, the output of the third variable gain amplifier 173 and the output of the fourth variable gain amplifier 174, respectively. The first variable gain amplifier 171 and the second variable gain amplifier 172 may process the signal of the first antenna 31 to adjust the signal amplitude of the first antenna 31 to be within the processable range of the receiver chip. The third variable gain amplifier 173 and the fourth variable gain amplifier 174 may process the signal of the second antenna 32 to adjust the signal amplitude of the second antenna 32 to the processable range of the receiver chip 40.

In one embodiment, the frequency dividing circuit 10 includes 4N phase shifters, each of which has an input terminal connected to an output terminal of one of the filters 14, and each of the input terminals 21 of the matrix switch 20 is connected to an output terminal of one of the phase shifters. The phase shifter may be an analog phase shifter, a digital phase shifter, or a low cost microstrip phase modulation loop. Since the phase performance of devices such as low noise amplifiers and splitters are inconsistent in different frequency bands, the accumulation of phase differences can severely affect the phase balance of the signal ultimately entering the receiver chip 40 when the number of devices on the signal link is large. The phase shifter can ensure the phase balance of each signal link, the phase flatness of the signal links is stable in a smaller range, and the phase flatness of the signal links can be maintained within 10 degrees. The present embodiment is described taking the case where the frequency dividing circuit 10 is provided with four phase shifters as an example. Referring to fig. 3, the frequency dividing circuit 10 includes a first phase shifter 181, a second phase shifter 182, a third phase shifter 183, and a fourth phase shifter 184. The input end of the first phase shifter 181 is connected with the output end of the first filter 141, the input end of the second phase shifter 182 is connected with the output end of the second filter 142, the input end of the third phase shifter 183 is connected with the output end of the third filter 143, and the input end of the fourth phase shifter 184 is connected with the output end of the fourth filter 144; the first input 211, the second input 212, the third input 213 and the fourth input 214 of the matrix switch 20 are connected to the output of the first phase shifter 181, the output of the second phase shifter 182, the output of the third phase shifter 183 and the output of the fourth phase shifter 184, respectively. The first phase shifter 181, the second phase shifter 182, the third phase shifter 183, and the fourth phase shifter 184 may adjust phases of signals output from the first filter 141, the second filter 142, the third filter 143, and the fourth filter 144 so that phases of signals input from the first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 are stabilized within a certain range.

Referring to fig. 3, when the frequency dividing circuit 10 is provided with an adjustable attenuator, a variable gain amplifier, and a phase shifter at the same time, the filter 14, the adjustable attenuator, the variable gain amplifier, and the phase shifter are sequentially connected in series on one signal link.

In summary, in the radio frequency front-end circuit provided by the embodiment of the present application, the frequency dividing circuit 10 divides the signal transmitted by each antenna 30 into two frequency bands, and the signals of different antennas 30 in different frequency bands are transmitted to different output ends of the frequency dividing circuit 10, so that the input end of the matrix switch 20 is connected to the signals of multiple frequency bands transmitted by multiple antennas 30. The multiple switch devices in the matrix switch 20 are switched under at least three switch state combinations, so that the receiver chip 40 receives single-antenna multi-frequency signals, multi-antenna single-frequency signals and multi-antenna multi-frequency signals respectively under various switch state combinations, and further three RTK positioning algorithms, namely single-antenna multi-frequency positioning, multi-antenna single-frequency directional attitude measurement and multi-antenna multi-frequency attitude measurement, are respectively executed based on the single-antenna multi-frequency signals, the multi-antenna single-frequency signals and the multi-antenna multi-frequency signals, so that the satellite navigation system can use one radio frequency front end circuit to perform single-antenna multi-frequency positioning, multi-antenna single-frequency directional attitude measurement and multi-antenna multi-frequency directional attitude measurement, the manufacturing cost of the radio frequency front end circuit is greatly saved, the integration level of the radio frequency front end circuit is improved, the size of the radio frequency front end circuit of the satellite navigation system is reduced, the problems of high manufacturing cost and large size of the radio frequency front end circuit of the satellite navigation system in the prior art are solved, the good radio frequency performance of the radio frequency front end is ensured, meanwhile the manufacturing cost and the small size of the satellite navigation system can be applied to various scenes, and the satellite navigation system is improved in applicability.

On the basis of the above embodiment, the present application further provides a satellite navigation system, which includes the antenna 30, the receiver chip 40, and the rf front-end circuit described in the above embodiment.

The radio frequency front-end circuit described in the embodiment is arranged in the satellite navigation system, so that the satellite navigation system can respectively realize single-antenna multi-frequency positioning, multi-antenna single-frequency directional attitude measurement and multi-antenna multi-frequency directional attitude measurement under the condition of using one radio frequency front-end circuit, the manufacturing cost of the radio frequency front-end circuit is greatly saved, the integration level of the radio frequency front-end circuit is improved, the size of the radio frequency front-end circuit is reduced, the problems of high manufacturing cost and large size of the radio frequency front-end circuit of the satellite navigation system in the prior art are solved, the excellent radio frequency performance of the radio frequency front-end is ensured, meanwhile, the low manufacturing cost and small size are realized, and the satellite navigation system can be applied to various scenes, and the applicability of the satellite navigation system is improved.

The foregoing description is only of the preferred embodiments of the application and the technical principles employed. The present application is not limited to the specific embodiments described herein, but is capable of numerous modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the application. Therefore, while the application has been described in connection with the above embodiments, the application is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit of the application, the scope of which is set forth in the following claims.

Claims

1. A radio frequency front-end circuit comprising a frequency divider circuit comprising at least two inputs and at least four outputs and a matrix switch comprising at least four inputs and at least four outputs, wherein:

2. The radio frequency front-end circuit of claim 1, wherein the three RTK positioning algorithms comprise a single antenna multi-frequency positioning algorithm, a multi-antenna single frequency directional pose measurement algorithm, and a multi-antenna multi-frequency directional pose measurement algorithm, wherein:

transmitting signals of each frequency band of a single antenna to the receiver chip under the condition that the matrix switch is in a first switch state combination, so that the receiver chip executes a single antenna multi-frequency positioning algorithm based on the received signals;

Transmitting signals of the same frequency band of each antenna to the receiver chip under the condition that the matrix switch is in a second switch state combination, so that the receiver chip executes a multi-antenna single-frequency directional gesture measurement algorithm based on the received signals;

and under the condition that the matrix switch is in a third switch state combination, transmitting signals of each frequency band of each antenna to the receiver chip so that the receiver chip executes a multi-antenna multi-frequency orientation gesture measurement algorithm based on the received signals.

3. The radio frequency front-end circuit of claim 2, wherein the frequency divider circuit comprises 2N splitters and 4N filters, the matrix switch comprises 4N inputs and 4N outputs, N is a positive integer greater than or equal to 1;

the input end of each divider is used for being correspondingly connected with an antenna, the input ends of each two filters are correspondingly connected with the output end of one divider, and each input end of the matrix switch is connected with the output end of one filter; the splitter is used for splitting signals input by the corresponding antenna into two paths of signals and transmitting the two paths of signals to the corresponding connected filters, and the two filters connected with the same splitter are used for filtering signals in different frequency bands.

4. The radio frequency front-end circuit of claim 3, wherein the frequency divider circuit comprises a first splitter, a second splitter, a first filter, a second filter, a third filter, and a fourth filter, and the matrix switch comprises four inputs and four outputs, wherein:

the input end of the first splitter is used for being connected with a first antenna, and the output end of the first splitter is connected with the input end of the first filter and the input end of the second filter; the input end of the second splitter is used for being connected with a second antenna, and the output end of the second splitter is connected with the input end of the third filter and the input end of the fourth filter; the four input ends of the matrix switch are respectively connected with the output end of the first filter, the output end of the second filter, the output end of the third filter and the output end of the fourth filter, and the four output ends of the matrix switch are respectively used for connecting a first receiver chip, a second receiver chip, a third receiver chip and a fourth receiver chip;

the first filter and the third filter are used for filtering signals outside the first frequency band, and the second filter and the fourth filter are used for filtering signals outside the second frequency band.

5. The radio frequency front-end circuit of claim 4, the first and second receiver chips being of a first type and the third and fourth receiver chips being of a second type, wherein:

when the matrix switch is in a first switch state combination, signals of a first frequency band and a second frequency band of the first antenna are respectively transmitted to a first receiver chip and a second receiver chip, so that the first receiver chip and the second receiver chip execute a single-antenna multi-frequency positioning algorithm based on the received signals to obtain a first positioning result; the signals of the first frequency band and the second frequency band of the second antenna are respectively transmitted to a third receiver chip and a fourth receiver chip, so that the third receiver chip and the fourth receiver chip execute a single-antenna multi-frequency positioning algorithm based on the received signals to obtain a second positioning result; the first positioning result and the second positioning result are used for testing the positioning performance of the first type of receiver chip and the second type of receiver chip.

6. The radio frequency front-end circuit of claim 4, the first and second receiver chips being of a first type and the third and fourth receiver chips being of a second type, wherein:

When the matrix switch is in a second switch state combination, signals of a first frequency range of the first antenna and signals of a first frequency range of the second antenna are respectively transmitted to a first receiver chip and a second receiver chip, so that the first receiver chip and the second receiver chip execute a multi-antenna single-frequency positioning algorithm based on the received signals to obtain a first orientation gesture measurement result; the signals of the first frequency bands of the first antenna and the second antenna are respectively transmitted to a third receiver chip and a fourth receiver chip, so that the third receiver chip and the fourth receiver chip execute a multi-antenna single-frequency positioning algorithm based on the received signals to obtain a second orientation gesture measurement result; the first orientation gesture measurement result and the second orientation gesture measurement result are used for testing the orientation gesture measurement performance of the first type of receiver chip and the second type of receiver chip.

7. A radio frequency front-end circuit as claimed in claim 3, characterized in that the frequency divider circuit comprises 4N adjustable attenuators, the input of each of which is connected to the output of one of the filters, and each of the inputs of the matrix switch is connected to the output of one of the adjustable attenuators.

8. A radio frequency front-end circuit as claimed in claim 3, characterized in that the frequency divider circuit comprises 4N variable gain amplifiers, the input of each of which is connected to the output of one of the filters, and each of the inputs of the matrix switch is connected to the output of one of the variable gain amplifiers.

9. A radio frequency front-end circuit as claimed in claim 3, characterized in that the frequency divider circuit comprises 4N phase shifters, each input of which is connected to an output of one of the filters, and each input of the matrix switch is connected to an output of one of the phase shifters.

10. A satellite navigation system, comprising: an antenna, a receiver chip and a radio frequency front-end circuit as claimed in any of claims 1-9.