A radio frequency front-end circuit and satellite navigation system

Abstract

The application discloses a kind of radio frequency front-end circuit and satellite navigation system.The radio frequency front-end circuit provided in the embodiment of the application includes frequency division circuit and matrix switch, frequency division circuit includes at least two input terminals and at least four output terminals, matrix switch includes at least four input terminals and at least four output terminals, the input terminal of frequency division circuit is used to connect antenna, each output terminal of frequency division circuit is connected with each input terminal of matrix switch respectively;Each input terminal of matrix switch is connected with each output terminal by switch device respectively, and the output terminal of matrix switch is used to connect receiver chip;Wherein, multiple switch devices in matrix switch are switched at least under three kinds of switch state combinations, so that receiver chip executes three kinds of RTK positioning algorithms under various switch state combinations respectively.Through the above technical means, the problem that the manufacturing cost of the radio frequency front-end circuit of satellite navigation system in the prior art is high and the volume is large is solved, and the applicability of satellite navigation system is improved.

Description

Technical Field

[0001] This application relates to the field of satellite navigation technology, and in particular to a radio frequency front-end circuit and a satellite navigation system. Background Technology

[0002] All types of electronic devices are equipped with satellite navigation systems. These systems use RTK (Real-Time Kinematic) positioning algorithms to determine the position and attitude of the electronic device based on satellite signals received by its antennas. Specifically, satellite navigation systems can perform precise positioning of electronic devices based on multi-frequency signals received from a single antenna, or they can perform orientation and attitude determination based on single-frequency or multi-frequency signals received from multiple antennas.

[0003] In existing technologies, to achieve precise positioning and orientation measurement functions, satellite navigation systems employ three radio frequency (RF) front-end circuits to receive multi-frequency signals from a single antenna, single-frequency signals from multiple antennas, and multi-frequency signals from multiple antennas, respectively. However, the manufacturing cost and size of these three RF front-end circuits are high, hindering the widespread adoption of satellite navigation systems. Summary of the Invention

[0004] This application provides a radio frequency (RF) front-end circuit and a satellite navigation system, which solves the problems of high manufacturing cost and large size of the RF front-end circuit in the prior art. While ensuring the excellent RF performance of the RF front-end, it has a lower manufacturing cost and smaller size. The satellite navigation system can be applied in various scenarios, thus improving the applicability of the satellite navigation system.

[0005] In a first aspect, this application provides a radio frequency front-end circuit, including a frequency divider circuit and a matrix switch. The frequency divider circuit includes at least two input terminals and at least four output terminals, and the matrix switch includes at least four input terminals and at least four output terminals, wherein:

[0006] The input terminal of the frequency divider circuit is used to connect to the antenna, and each output terminal of the frequency divider circuit is respectively connected to each input terminal of the matrix switch; each input terminal of the matrix switch is respectively connected to each output terminal through a switching device, and the output terminal of the matrix switch is used to connect to the receiver chip.

[0007] The multiple switching devices within the matrix switch switch switch at least switch between three different switching state combinations, so that the receiver chip executes three different RTK positioning algorithms under each of the various switching state combinations.

[0008] Secondly, this application provides a satellite navigation system, including an antenna, a receiver chip, and a radio frequency front-end circuit as described in the first aspect.

[0009] In this application, the RF front-end circuit includes a frequency divider circuit and a matrix switch. The frequency divider circuit includes at least two input terminals and at least four output terminals, and the matrix switch includes at least four input terminals and at least four output terminals. Each input terminal of the frequency divider circuit is connected to an antenna, and each output terminal of the frequency divider circuit is connected to a corresponding input terminal of the matrix switch. The input terminal of the frequency divider circuit receives the signal transmitted by the antenna. The frequency divider circuit can divide the signal transmitted by each antenna into two frequency bands, and send the signals of different frequency bands and different antennas to different output terminals of the frequency divider circuit, so that the input terminal of the matrix switch can be connected to signals of multiple frequency bands transmitted by multiple antennas. By switching multiple switching devices in the matrix switch in at least three switching state combinations, the receiver chip can receive single-antenna multi-frequency signals, multi-antenna single-frequency signals, and multi-antenna multi-frequency signals respectively under various switching state combinations. Then, based on the single-antenna multi-frequency signals, multi-antenna single-frequency signals, and multi-antenna multi-frequency signals, it can execute three RTK positioning algorithms: single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude measurement, and multi-antenna multi-frequency orientation and attitude measurement, respectively. Through the aforementioned technical means, the satellite navigation system uses a single radio frequency (RF) front-end circuit to achieve single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude measurement, and multi-antenna multi-frequency orientation and attitude measurement, respectively. This significantly reduces the manufacturing cost of the RF front-end circuit, improves its integration, and reduces its size. It solves the problems of high manufacturing cost and large size of the RF front-end circuit in existing satellite navigation systems. While ensuring excellent RF performance, it also has low manufacturing cost and small size, allowing the satellite navigation system to be applied in various scenarios and improving its applicability. Attached Figure Description

[0010] Figure 1 This is a schematic block diagram of a radio frequency front-end circuit provided in an embodiment of this application;

[0011] Figure 2 This is a schematic diagram of the frequency divider circuit provided in the embodiments of this application;

[0012] Figure 3 This is a schematic diagram of the structure of the radio frequency front-end circuit provided in the embodiments of this application;

[0013] Figure 4 This is a schematic diagram of the matrix switch provided in an embodiment of this application;

[0014] Figure 5 This is a first schematic diagram of the first switch state combination provided in the embodiments of this application;

[0015] Figure 6 This is a second schematic diagram of the first switch state combination provided in the embodiments of this application;

[0016] Figure 7This is a first schematic diagram of the second switch state combination provided in the embodiments of this application;

[0017] Figure 8 This is a second schematic diagram of the second switch state combination provided in the embodiments of this application;

[0018] Figure 9 This is a schematic diagram of the third switch state combination provided in an embodiment of this application;

[0019] Figure 10 This is a schematic diagram of another matrix switch provided in an embodiment of this application;

[0020] In the diagram, 10 is the frequency divider circuit; 11 is the input terminal of the frequency divider circuit; 12 is the output terminal of the frequency divider circuit; 13 is the splitter; 131 is the first splitter; 132 is the second splitter; 14 is the filter; 141 is the first filter; 142 is the second filter; 143 is the third filter; 144 is the fourth filter; 151 is the first low-noise amplifier; 152 is the second low-noise amplifier; 161 is the first adjustable attenuator; 162 is the second adjustable attenuator; 163 is the third adjustable attenuator; 164 is the fourth adjustable attenuator; 171 is the first variable gain amplifier; 172 is the second variable gain amplifier; 173 is the third variable gain amplifier; 174 is the fourth variable gain amplifier; 181 is the first phase shifter; 182 is the second phase shifter; 183 is the third phase shifter; 184 is the fourth phase shifter; 20 is the matrix switch; 21 is the matrix switch... Input terminals; 211, First input terminal; 212, Second input terminal; 213, Third input terminal; 214, Fourth input terminal; 22, Output terminal of matrix switch; 221, First output terminal; 222, Second output terminal; 223, Third output terminal; 224, Fourth output terminal; 30, Antenna; 31, First antenna; 32, Second antenna; 40, Receiver chip; 41, First receiver chip; 42, Second receiver chip; 43, Third receiver chip; 44, Fourth receiver chip; S1, Single-pole triple-throw switch; S2, First single-pole double-throw switch; S3, Single-pole quadruple-throw switch; S4, Second single-pole double-throw switch; S5, Third single-pole double-throw switch; S6, Fourth single-pole double-throw switch; S7, Fifth single-pole double-throw switch; S8, Sixth single-pole double-throw switch; R1, First resistor; R2, Second resistor; R3, Third resistor; R4, Fourth resistor. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application will be described in further detail below with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of this application and not intended to limit it.

[0022] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0023] In common existing implementations, satellite navigation systems use three radio frequency (RF) front-end circuits to receive multi-frequency signals from a single antenna, single-frequency signals from multiple antennas, and multi-frequency signals from multiple antennas, respectively, to implement three different RTK positioning algorithms: single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude determination, and multi-antenna multi-frequency orientation and attitude determination. However, the manufacturing cost of these three RF front-end circuits is high, and their large size hinders the widespread use of satellite navigation systems. Furthermore, testing the performance of various receiver chips in single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude determination requires configuring a matching receiver chip for each RF front-end circuit, further increasing testing costs.

[0024] To address the aforementioned issues, this application provides a radio frequency front-end circuit that ensures excellent radio frequency performance while maintaining low manufacturing costs and a small size.

[0025] Figure 1 This is a schematic block diagram of a radio frequency front-end circuit provided in an embodiment of this application. For example... Figure 1 As shown, the RF front-end circuit includes a frequency divider circuit 10 and a matrix switch 20. The frequency divider circuit 10 includes at least two input terminals 11 and at least four output terminals 12, and the matrix switch 20 includes at least four input terminals 21 and at least four output terminals 22. The input terminals 11 of the frequency divider circuit 10 are used to connect to the antenna 30, and each output terminal 12 of the frequency divider circuit 10 is connected to each input terminal 21 of the matrix switch 20. Each input terminal 21 of the matrix switch 20 is connected to each output terminal 22 through a switching device, and the output terminal 22 of the matrix switch 20 is used to connect to the receiver chip 40. The multiple switching devices within the matrix switch 20 switch in at least three switching state combinations, so that the receiver chip 40 executes three RTK positioning algorithms under various switching state combinations.

[0026] In this embodiment, antenna 30 is a receiving antenna that supports multi-band signals, including but not limited to broadband antennas and multi-band antennas. Each input terminal of frequency divider circuit 10 is connected to one antenna 30. When antenna 30 receives multi-band signals transmitted by a satellite, it transmits the received multi-band signals to the input terminal of frequency divider circuit 10. After receiving the multi-band signals transmitted by each antenna 30 from each input terminal 11, frequency divider circuit 10 divides each multi-band signal into two single-band signals with different frequency bands. Since different satellite systems correspond to different operating frequency bands, for example, the operating frequency bands of the BeiDou satellite system include B1, B2, and B3, and the operating frequency bands of the Global Positioning System include L1, L2, and L5, the frequency division function of frequency divider circuit 10 can be selected according to the operating frequency band of the satellite navigation system. For example, when the operating frequency bands of the satellite navigation system are B1, B2, and B3, the frequency divider circuit 10 can divide the multi-band signal transmitted by the antenna 30 into signals in the B1 band and signals in the B2 / B3 bands. When the operating frequency bands of the satellite navigation system are L1, L2, and L5, the frequency divider circuit 10 can divide the multi-band signal transmitted by the antenna 30 into signals in the L1 band and signals in the L2 / L5 bands. The frequencies of the B2 and B3 bands are similar, and by default, the B2 and B3 bands are considered the same single band. Similarly, the frequencies of the L2 and L5 bands are similar, and by default, the L2 and L5 bands are considered the same single band. After dividing the multi-band signal transmitted by each antenna 30 into two single-band signals, the frequency divider circuit 10 sends the two single-band signals corresponding to each antenna 30 to the two output terminals 12 of the frequency divider circuit 10, and each output terminal 12 of the frequency divider circuit 10 receives only one single-band signal. The output terminal 12 of the frequency divider circuit 10 is connected one-to-one with the input terminal 21 of the matrix switch 20. The output terminal 12 of the frequency divider circuit 10 can transmit the received single-band signal to the corresponding input terminal of the matrix switch 20, so that each input terminal 31 of the matrix switch 20 receives two single-band signals from each antenna 30. This embodiment is described using the operating frequency bands of the satellite navigation system as L1, L2 and L5.

[0027] The input terminals 21 and output terminals 22 of the matrix switch 20 can be connected in a one-to-one, one-to-many, or many-to-one manner. Regardless of the connection structure, under various switching state combinations, input terminals 21 and output terminals 22 are selectively connected or not connected. For example, if one input terminal 21 of the matrix switch 20 is connected to three output terminals 22, then that input terminal 21 will only be connected to one of the output terminals 22 or not connected to any of them. Similarly, if one output terminal 22 is connected to multiple output terminals 21, then that output terminal will also only be connected to one of the input terminals 21 or not connected to any of them. Here, the switching state combination can be understood as the combination of the various switching devices in the matrix switch when they are in their corresponding switching states.

[0028] This embodiment describes a one-to-one connection between input terminal 21 and output terminal 22. Input terminal 21 and the corresponding output terminal 22 are connected via a switching device. The closing or opening of this switching device controls whether the input terminal 21 and the corresponding output terminal 22 are in a conducting or disconnected state. When the input terminal 21 of the matrix switch 20 is in a conducting state, the single-band signal received by the input terminal 21 can be transmitted to the corresponding output terminal 22; when the input terminal 21 of the matrix switch 20 is in a disconnected state, the single-band signal received by the input terminal 21 cannot be transmitted to the corresponding output terminal 22. The control unit of the electronic device or satellite navigation system can control each switching device within the matrix switch to remain in its corresponding switching state according to the RTK positioning algorithm to be executed by the receiver chip.

[0029] The receiver chip can execute three RTK positioning algorithms: single-antenna multi-frequency positioning algorithm, multi-antenna single-frequency orientation and attitude determination algorithm, and multi-antenna multi-frequency orientation and attitude determination algorithm. Specifically, when the matrix switch is in the first switching state combination, the signals of each frequency band of a single antenna are transmitted to the receiver chip, enabling the receiver chip to execute the single-antenna multi-frequency positioning algorithm based on the received signals. For example, when the receiver chip is about to execute the single-antenna multi-frequency positioning algorithm, the RF front-end circuit can transmit the single-band signals of multiple frequency bands received by the single antenna 30 to the receiver chip 40. At this time, the control unit can control the switching devices between the input terminal 21 and the corresponding output terminal 22 of the matrix switch 20 that receive single-band signals from two different frequency bands of the same antenna 30 to close, and the switching devices between the other input terminals 21 and the corresponding output terminals 22 to open, so that the two output terminals 22 of the matrix switch 20 that receive single-band signals respectively send two single-band signals from the same antenna 30 to the two receiver chips 40 connected to them, so that the receiver chip 40 that receives the signals can accurately locate the electronic device based on the two single-band signals from the antenna 30.

[0030] When the matrix switch is in the second switching state combination, signals of the same frequency band from each antenna are transmitted to the receiver chip, enabling the receiver chip to execute a multi-antenna single-frequency orientation and attitude measurement algorithm based on the received signals. For example, when the receiver chip is about to execute the multi-antenna single-frequency orientation and attitude measurement algorithm, the RF front-end circuit can transmit single-band signals of the same frequency band received by multiple antennas 30 to the receiver chip 40. At this time, the control unit can control the switching devices between the input terminal 21 and the corresponding output terminal 22 of the matrix switch 20 that receive single-band signals of the same frequency band from different antennas 30 to close, while the switching devices between the remaining input terminals 21 and the corresponding output terminals 22 are opened. This causes each output terminal 22 of the matrix switch 20 that receives single-band signals to send single-band signals of the same frequency band from multiple antennas 30 to the corresponding connected receiver chips 40, so that the receiver chip 40 receiving the signals can perform orientation and attitude measurement on the electronic device based on the single-band signals of the same frequency band from multiple antennas 30.

[0031] When the matrix switch is in the third switching state combination, the signals of each frequency band of each antenna are transmitted to the receiver chip, enabling the receiver chip to execute a multi-antenna multi-frequency orientation and attitude measurement algorithm based on the received signals. For example, when the receiver chip is about to execute the multi-antenna multi-frequency orientation and attitude measurement algorithm, the RF front-end circuit can transmit single-band signals from multiple frequency bands received by the multiple antennas 30 to the receiver chip 40. At this time, the control unit can control all the switching devices in the matrix switch 20 to close, so that all output terminals 22 of the matrix switch 20 respectively send single-band signals from two different frequency bands of the multiple antennas 30 to the corresponding connected receiver chips 40, so that the receiver chip 40 receiving the signals can perform orientation and attitude measurement on the electronic device based on the single-band signals from the two different frequency bands of the multiple antennas 30.

[0032] It needs to be explained that, Figure 1 Although the frequency divider circuit 10 is shown connecting four antennas 30, it is not limited to connecting four antennas 30. The number of antennas 30 connected to the frequency divider circuit 10 can be set according to the actual needs of the satellite navigation system. The number of receiver chips 40 in the satellite navigation system is twice the number of antennas 30, because each receiver chip 40 is used to receive a single-band signal from one antenna 30. If the receiver chip used has two or more inputs, the number of receiver chips can be adaptively reduced.

[0033] In one embodiment, Figure 2 This is a schematic diagram of the frequency divider circuit provided in an embodiment of this application. Figure 2As shown, the frequency divider circuit 10 includes 2N splitters 13 and 4N filters 14, and the matrix switch 20 includes 4N input terminals 21 and 4N output terminals 22, where N is a positive integer greater than or equal to 1. Each input terminal of a splitter 13 is connected to a corresponding antenna 30, and the input terminals of every two filters 14 are connected to the output terminals of one splitter 13. Each input terminal 21 of the matrix switch 20 is connected to the output terminal of one filter 14. The splitter 13 is used to split the signal input from the corresponding antenna 30 into two signals and send them to the corresponding connected filters 14. Two filters 14 connected to the same splitter 13 are used to filter signals of different frequency bands.

[0034] For example, the input terminal of each splitter 13 in the frequency divider circuit 10 is the input terminal of the frequency divider circuit 10, and the output terminal of each filter 14 is the output terminal of the frequency divider circuit 10. Accordingly, the frequency divider circuit 10 includes 2N input terminals and 4N output terminals. The frequency divider circuit 10 can be connected to 2N antennas 30, and the matrix switch 20 can be connected to 4N receiver chips 40. For ease of understanding, the frequency divider circuit 10 can be regarded as including 2N frequency divider sub-circuits. Each frequency divider sub-circuit includes one splitter 13 and two filters 14. The frequency divider sub-circuit is used to divide the multi-band signal transmitted by the antenna 30 connected to the splitter 13 into two single-band signals with different frequency bands. In one frequency divider sub-circuit, the splitter 13 divides the multi-band signal received by the corresponding antenna 30 into two multi-band signals, and transmits the two multi-band signals to the two corresponding filters 14 respectively. Assuming the current satellite navigation system operates in the L1, L2, and L5 frequency bands, one filter 14 in the frequency division sub-circuit is a SAW (Surface Acoustic Wave) filter supporting the L1 band, which effectively suppresses signals outside the L1 band. The other filter 14 is a SAW filter supporting the L2 / L5 bands, which also effectively suppresses signals outside the L2 / L5 bands. The SAW filter supporting the L1 band filters the received multi-band signals and outputs L1 band signals, while the SAW filter supporting the L1 band filters the received multi-band signals and outputs L2 / L5 band signals. Each frequency division sub-circuit has the same structure, and each can divide the multi-band signals received by the corresponding connected antenna 30 into L1 band signals and L2 / L5 band signals, so that each input terminal of the matrix switch 20 can receive the L1 band signals and L2 / L5 band signals received by the corresponding antenna 30 of each frequency division sub-circuit.

[0035] In this embodiment, the splitter 13 can be a broadband power divider or a duplexer whose operating bandwidth covers the operating frequency band of the satellite navigation system. The broadband power divider includes, but is not limited to, patch-type integrated power dividers and Wilkinson power dividers. For example, when the operating frequency band of the satellite navigation system is L1, L2, or L5, the splitter 13 can have an operating bandwidth covering the L1, L2, and L5 frequency bands.

[0036] To reduce the manufacturing cost and energy consumption of the satellite navigation system, the system uses two antennas 30 to receive signals from the satellite and four receiver chips 40 to process the signals. Accordingly, when the satellite navigation system has two antennas 30 and four receiver chips 40, the frequency divider circuit 10, with two splitters 13 and four filters 14, can divide the signals transmitted by the antennas 30. The matrix switch 20, with four input terminals 21 and four output terminals 22, can transmit the signals transmitted by the frequency divider circuit 10 to the receiver chips 40 according to the operating mode of the satellite navigation system. In this embodiment, Figure 3 This is a schematic diagram of the radio frequency front-end circuit provided in an embodiment of this application. Figure 3 As shown, the frequency divider 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. The matrix switch 20 includes four input terminals 21 and four output terminals 22. The input terminal of the first splitter 131 is used to connect to the first antenna 31, and the output terminal of the first splitter 131 is connected to the input terminal of the first filter 141 and the input terminal of the second filter 142. The input terminal of the second splitter 132 is used to connect to the second antenna 32, and the output terminal of the second splitter 132 is connected to the input terminal of the third filter 143 and the input terminal of the fourth filter 144. The four input terminals 21 of the matrix switch 20 are respectively connected to the output terminals of the first filter 141, the second filter 142, the third filter 143 and the fourth filter 144, and the four output terminals 22 of the matrix switch 20 are respectively used to connect to the first receiver chip 41, the second receiver chip 42, the third receiver chip 43 and the fourth receiver chip 44. Among them, 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 to filter signals outside the second frequency band.

[0037] This embodiment uses the L1 band as the first frequency band and the L2 / L5 band as the second frequency band as an example for description. 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 bands as an example for description. 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 is transmitted to the first filter 141, and the other path is transmitted to the second filter 142. The first filter 141 filters out the frequency band signals other than the L1 band from the received multi-band signal and outputs the L1 band signal. The second filter 142 filters out the frequency band signals other than the L2 / L5 band from the received multi-band signal and outputs the L2 / L5 band signal. The second antenna 32 transmits the received multi-band signal to the second splitter 132, which splits the multi-band signal into two paths: one path is transmitted to the third filter 143, and the other path is transmitted to the fourth filter 144. The third filter 143 filters out all frequency bands except for the L1 band from the received multi-band signal, outputting the L1 band signal. The fourth filter 144 filters out all frequency bands except for the L2 / L5 bands from the received multi-band signal, outputting the L2 / L5 band signals.

[0038] Furthermore, the matrix switch 20 has four input terminals 21, including a first input terminal 211, a second input terminal 212, a third input terminal 213, and a fourth input terminal 214, and four output terminals 22, including a first output terminal 221, a second output terminal 222, a third output terminal 223, and a fourth output terminal 224. The output terminals of the first filter 141, the second filter 142, the third filter 144, and the fourth filter 144 are respectively connected to the first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 of the matrix switch 20.

[0039] In the configuration where the input terminals 21 and 22 of the matrix switch 20 are connected one-to-one, the first input terminal 211 is connected to the first output terminal 221 via a first switching device, the second input terminal 212 is connected to the second output terminal 222 via a second switching device, the third input terminal 213 is connected to the third output terminal 223 via a third switching device, and the fourth input terminal 214 is connected to the fourth output terminal 224 via a fourth switching device. The first output terminal 221, the second output terminal 222, the third output terminal 223, and the fourth output terminal 224 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 transmits the signal from the L1 band of the first antenna 31 to the first input terminal 211, the second filter 142 transmits the signal from the L2 / L5 band of the first antenna 31 to the second input terminal 212, the third filter 143 transmits the signal from the L1 band of the second antenna 32 to the third input terminal 213, and the fourth filter 144 transmits the signal from the L2 / L5 band of the second antenna 32 to the fourth input terminal 214.

[0040] In this embodiment, the first switch state combination can be that the first and second switch devices are closed, and the third and fourth switch devices are open. At this time, the first input terminal 211 and the second input terminal 212 transmit the signals from the L1 band and L2 / L5 band of the first antenna 31 to the first receiver chip 41 and the second receiver chip 42, respectively. The first receiver chip 41 and the second receiver chip 42 can then perform a single-antenna multi-frequency positioning algorithm based on the received signals from the L1 band and L2 / L5 band of the first antenna 31. Alternatively, the first switch state combination can also be that the first and second switch devices are open, and the third and fourth switch devices are closed. At this time, the third input terminal 213 and the fourth input terminal 214 transmit the signals from the L1 band and L2 / L5 band of the second antenna 32 to the third receiver chip 43 and the fourth receiver chip 44, respectively. The third receiver chip 43 and the fourth receiver chip 44 can then perform a single-antenna positioning algorithm based on the received signals from the L1 band and L2 / L5 band of the second antenna 32.

[0041] The second switch state combination can be that the first and third switch devices are closed, and the second and fourth switch devices are open. In this case, the first input terminal 211 and the third input terminal 213 transmit the signals from the L1 band of the first antenna 31 and the second antenna 32 to the first receiver chip 41 and the third receiver chip 43, respectively. The first receiver chip 41 and the third receiver chip 43 can perform a multi-antenna single-frequency orientation and attitude determination algorithm based on the received signals from the L1 band of the first antenna 31 and the second antenna 32. Alternatively, the second switch state combination can also be that the first and third switch devices are open, and the second and fourth switch devices are closed. In this case, the second input terminal 212 and the fourth input terminal 214 transmit the signals from the L2 / L5 band of the first antenna 31 and the second antenna 32 to the second receiver chip 42 and the fourth receiver chip 44, respectively. The second receiver chip 42 and the fourth receiver chip 44 can perform a multi-antenna single-frequency orientation and attitude determination algorithm based on the signals from the L2 / L5 band of the first antenna 31 and the second antenna 32.

[0042] The third switch state combination can be that the first switch device, the second switch device, the third switch device, and the fourth switch device are closed. At this time, the first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 transmit the signals from the L1 band and the L2 / L5 band of the first antenna 31, as well as the signals from the L1 band and the L2 / L5 band of 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, respectively. This allows the first receiver chip 41, the second receiver chip 42, the third receiver chip 43, and the fourth receiver chip 44 to execute a multi-antenna multi-frequency orientation and attitude measurement algorithm based on the received signals.

[0043] In the case where the input terminal 21 and output terminal 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.

[0044] 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, and 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 signals from the L1 band and the L2 / L5 band of the first antenna 31 to the first receiver chip 41 and the second receiver chip 42, respectively. The first receiver chip 41 and the second receiver chip 42 can 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. 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, and 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 signals from the L1 band and the L2 / L5 band of the second antenna 32 to the third receiver chip 43 and the fourth receiver chip 44, respectively. The third receiver chip 43 and the fourth receiver chip 44 can perform a single-antenna multi-frequency positioning algorithm based on the signals from the L1 band and the L2 / L5 band of the second antenna 32.

[0045] When the matrix switch is in the second switch state combination, the first input terminal 211 is connected to the first output terminal 221, the second input terminal 212 is not connected to the second output terminal 222, the third input terminal 213 is connected to the second output terminal 222, and the fourth input terminal 214 is not connected to the fourth output terminal 224. The first input terminal 211 and the third input terminal 213 transmit the signals from the L1 band of the first antenna 31 and the second antenna 32 to the first receiver chip 41 and the second receiver chip 42, respectively. The first receiver chip 41 and the second receiver chip 42 execute a multi-antenna single-frequency orientation and attitude measurement algorithm based on the signals from the L1 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 terminal 211 is connected to the third output terminal 223, the second input terminal 212 is not connected to the second output terminal 222, the third input terminal 213 is connected to the fourth output terminal 224, and the fourth input terminal 214 is not connected to the fourth output terminal 224. The second input terminal 212 and the fourth input terminal 214 transmit the signals from the L2 / L5 frequency bands of the first antenna 31 and the second antenna 32 to the third receiver chip 43 and the fourth receiver chip 44, respectively. The third receiver chip 43 and the fourth receiver chip 44 can perform a multi-antenna single-frequency orientation and attitude measurement algorithm based on the signals from the L2 / L5 frequency bands of the first antenna 31 and the second antenna 32.

[0046] When the matrix switch is in the third 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 connected to the third output terminal 223, and the fourth input terminal 214 is connected to the fourth output terminal 224. The first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 transmit the signals from the L1 band and the L2 / L5 band of the first antenna 31, as well as the signals from the L1 band and the L2 / L5 band of 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, respectively. 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.

[0047] As described above, the matrix switch has two first switch state combinations, under which different receiver chips execute the single-antenna multi-frequency positioning algorithm; the matrix switch also has two second switch state combinations, under which different receiver chips execute the multi-antenna single-frequency positioning algorithm. Therefore, this embodiment proposes that when testing the performance of the receiver chips, the first receiver chip 41 and the second receiver chip 42 can be configured as first-type receiver chips, and the third and fourth receiver chips can be configured as second-type receiver chips, to compare the performance of the two types of receiver chips in single-antenna multi-frequency positioning and multi-antenna single-frequency orientation and attitude measurement modes.

[0048] In this embodiment, when the matrix switch is in the first switching state combination, the 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 transmitted to the third receiver chip and the fourth receiver chip, respectively, 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.

[0049] For example, in one first switching state combination, the first input terminal 211 is connected to the first output terminal 221, and the second input terminal 212 is connected to the second output terminal 222. The first receiver chip 41 and the second receiver chip 42 receive signals from the L1 band and L2 / L5 band of the first antenna 31, respectively. 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 L2 / L5 band of the first antenna 31 to obtain a first positioning result. In another first switching state combination, the third input terminal 213 is connected to the third output terminal 223, and the fourth input terminal 214 is connected to the fourth output terminal 224. The third receiver chip 43 and the fourth receiver chip 44 receive signals from the L1 band and L2 / L5 band of the second antenna 32, respectively. The third receiver chip 43 and the fourth receiver chip 44 perform a single-antenna multi-frequency positioning algorithm based on the signals from the L1 band and L2 / L5 band of the second antenna 32 to obtain a second positioning result. The first positioning result can be compared with the second positioning result to analyze the multi-antenna single-frequency positioning performance of the first and second type receiver chips.

[0050] In this embodiment, when the matrix switch is in the second switching state combination, the signals of the first frequency band of the first antenna and the second 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 multi-antenna single-frequency positioning algorithm based on the received signals to obtain a first orientation measurement result; the signals of the first frequency band of the first antenna and the second antenna are transmitted to the third receiver chip and the fourth receiver chip, respectively, 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 measurement result; the first orientation measurement result and the second orientation measurement result are used to test the orientation measurement performance of the first type of receiver chip and the second type of receiver chip.

[0051] For example, in a second switching state combination, the first input terminal 211 is connected to the first output terminal 221, and 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 from the L1 band of the first antenna 31 and the second antenna 32. The first receiver chip 41 and the second receiver chip 42 perform a multi-antenna single-frequency orientation and attitude measurement algorithm based on the signals from the L1 band of the first antenna 31 and the second antenna 32 to obtain a first orientation and attitude measurement result. Connecting the first input terminal 211 to the third output terminal 223 and the third input terminal 213 to the fourth output terminal 224, the third receiver chip 43 and the fourth receiver chip 44 receive signals from the L1 band of the first antenna 31 and the second antenna 32. The third receiver chip 43 and the fourth receiver chip 44 perform a multi-antenna single-frequency orientation and attitude measurement algorithm based on the signals from the L1 band of the first antenna 31 and the second antenna 32 to obtain a second orientation and attitude measurement result. The first orientation measurement result can be compared with the second orientation measurement result to analyze the multi-antenna single-frequency orientation measurement performance of the first and second type receiver chips.

[0052] In one embodiment, Figure 4 This is a schematic diagram of the matrix switch provided in an embodiment of this application. Figure 4As shown, 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 quadruple-throw switch S3. The main terminal of the single-pole triple-throw switch S1 is connected to the first input terminal 211. The three moving terminals of the single-pole triple-throw switch S1 are respectively connected to the first moving terminal of the third single-pole double-throw switch S5, the first moving terminal of the fifth single-pole double-throw switch S7, and ground. The main terminal of the third single-pole double-throw switch S5 is connected to the first output terminal 221. The main terminal of the fifth single-pole double-throw switch S7 is connected to the third output terminal 223. The main terminal of the first single-pole double-throw switch S2 is connected to the second input terminal 212. The two moving terminals of the first single-pole double-throw switch S2 are respectively connected to the first moving terminal of the fourth single-pole double-throw switch S6 and ground. The fourth single-pole double-throw switch S6... The main connection point of switch S6 is connected to the second output terminal 222. The main connection point of single-pole four-throw switch S3 is connected to the third input terminal 213. The four moving connection points of single-pole four-throw switch S3 are respectively connected to the second moving connection point of fourth single-pole double-throw switch S6, the second moving connection point of fifth single-pole double-throw switch S7, the first moving connection point of sixth single-pole double-throw switch S8, and ground. The main connection point of sixth single-pole double-throw switch S8 is connected to the fourth output terminal 224. The main connection point of second single-pole double-throw switch S4 is connected to the fourth input terminal 214. The two connection points of second single-pole double-throw switch S4 are respectively connected to the second moving connection point of sixth single-pole double-throw switch S8 and ground. In this embodiment, the moving connection points of single-pole three-throw switch S1, first single-pole double-throw switch S2, single-pole four-throw switch S3, and second single-pole double-throw switch S4 are respectively connected to ground through resistors. The resistance value can be set according to the actual situation, generally set to 50 ohms.

[0053] In this embodiment, the first switch state combination can be that the first input terminal 211 is connected to the first output terminal 221 through a single-pole triple-throw switch S1 and a third single-pole double-throw switch S5, and the second input terminal 212 is connected to the second output terminal 222 through a second single-pole double-throw switch S4 and a fourth single-pole double-throw switch S6. Alternatively, the first switch state combination can also be that the third input terminal 213 is connected to the third output terminal 223 through a single-pole quadruple-throw switch S3 and a fifth single-pole double-throw switch S7, and the fourth input terminal 214 is 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.

[0054] Figure 5 This is a first schematic diagram of a first switch state combination provided in an embodiment of this application. For example... Figure 5As shown, the main terminal of the single-pole triple-throw switch S1 is connected to the first moving terminal of the single-pole triple-throw switch S1, and the main terminal of the third single-pole double-throw switch S5 is connected to the first moving terminal of the third single-pole double-throw switch S5. Since the first moving terminal of the single-pole triple-throw switch S1 is connected to the first moving terminal of the third single-pole double-throw switch S5, the first input terminal 211 is connected to the first output terminal 221. The main terminal of the first single-pole double-throw switch S2 is connected to the first moving terminal of the first single-pole double-throw switch S2, and the main terminal of the fourth single-pole double-throw switch S6 is connected to the first moving terminal of the fourth single-pole double-throw switch S6. Since the first moving terminal of the first single-pole double-throw switch S2 is connected to the first moving terminal of the fourth single-pole double-throw switch S6, the second input terminal 212 is connected to the second output terminal 222. The first receiver chip 41 and the second receiver chip 42 acquire signals from the L1 and L2 / L5 frequency bands of 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 from the L1 and L2 / L5 frequency bands of the first antenna 31. Simultaneously, the main terminal of the single-pole four-throw switch S3 is connected to the fourth moving terminal of the single-pole four-throw switch S3. Since the fourth moving terminal of the single-pole four-throw switch S3 is grounded through the third resistor R3, the third input terminal 213 is grounded, and the third resistor R3 can absorb the load of the third input terminal 213. The main terminal of the second single-pole double-throw switch S4 is connected to the second moving terminal of the second single-pole double-throw switch S4. Since the second moving terminal of the second single-pole double-throw switch S4 is grounded through the fourth resistor R4, the fourth input terminal 214 is grounded, and the fourth resistor R4 can absorb the load of the fourth input terminal 214. The absorption of load by the third resistor R3 and the fourth resistor R4 solves the power reflection problem and greatly improves the stability of the satellite navigation system.

[0055] Figure 6 This is a second schematic diagram of the first switch state combination provided in the embodiments of this application. For example... Figure 6As shown, the main terminal of the single-pole four-throw switch S3 is connected to the second moving terminal of the single-pole four-throw switch S3, and the main terminal of the fifth single-pole double-throw switch S7 is connected to the second moving terminal of the fifth single-pole double-throw switch S7. Since the second moving terminal of the single-pole four-throw switch S3 is connected to the second moving terminal of the fifth single-pole double-throw switch S7, the third input terminal 213 is connected to the third output terminal 223. The main terminal of the second single-pole double-throw switch S4 is connected to the first moving terminal of the second single-pole double-throw switch S4, and the main terminal of the sixth single-pole double-throw switch S8 is connected to the second moving terminal of the sixth single-pole double-throw switch S8. Since the first moving terminal of the second single-pole double-throw switch S4 is connected to the second moving terminal of the sixth single-pole double-throw switch S8, 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 from the L1 and L2 / L5 frequency bands of 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 from the L1 and L2 / L5 frequency bands of the second antenna 32. Simultaneously, the main terminal of the single-pole triple-throw switch S1 is connected to its third moving terminal. Since the third moving terminal of the single-pole triple-throw switch S1 is grounded through the first resistor R1, the first input terminal 211 is grounded, and the first resistor R1 absorbs the load of the first input terminal 211. The main terminal of the first single-pole double-throw switch S2 is connected to its second moving terminal. Since the second moving terminal of the first single-pole double-throw switch S2 is grounded through the second resistor R2, the second input terminal 212 is grounded, and the second resistor R2 absorbs the load of the second input terminal 212. The absorption of load by the first resistor R1 and the second resistor R2 solves the power reflection problem and greatly improves the stability of the satellite navigation system.

[0056] In this embodiment, the second switch state combination can be such that the first input terminal 211 is connected to the first output terminal 221 via a single-pole triple-throw switch S1 and a third single-pole double-throw switch S5, and the third input terminal 213 is connected to the second output terminal 222 via a single-pole quadruple-throw switch S3 and a fourth single-pole double-throw switch S6. Alternatively, the second switch state combination can also be such that the first input terminal 211 is connected to the third output terminal 223 via a single-pole triple-throw switch S1 and a fifth single-pole double-throw switch S7, and the third input terminal 213 is connected to the fourth output terminal 224 via a single-pole quadruple-throw switch S3 and a sixth single-pole double-throw switch S8.

[0057] Figure 7 This is a first schematic diagram of the second switch state combination provided in the embodiments of this application. For example... Figure 7As shown, the main terminal of the single-pole three-throw switch S1 is connected to the first moving terminal of the single-pole three-throw switch S1, and the main terminal of the third single-pole double-throw switch S5 is connected to the first moving terminal of the third single-pole double-throw switch S5. Since the first moving terminal of the single-pole three-throw switch S1 is connected to the first moving terminal of the third single-pole double-throw switch S5, the first input terminal 211 is connected to the first output terminal 221. The main terminal of the single-pole four-throw switch S3 is connected to the first moving terminal of the single-pole four-throw switch S3, and the main terminal of the fourth single-pole double-throw switch S6 is connected to the second moving terminal of the fourth single-pole double-throw switch S6. Since the first moving terminal of the single-pole four-throw switch S3 is connected to the second moving terminal of the fourth single-pole double-throw switch S6, the third input terminal 213 is connected to the second output terminal 222. The first receiver chip 41 and the second receiver chip 42 acquire signals from the L1 band of the first antenna 31 and the second antenna 32 through the first output terminal 221 and the second output terminal 222, respectively, and can perform orientation and attitude measurement based on the signals from the L1 band of the first antenna 31 and the second antenna 32. Simultaneously, the main terminal of the first single-pole double-throw switch S2 connects to the second moving terminal of the first single-pole double-throw switch S2. Since the second moving terminal of the first single-pole double-throw switch S2 is grounded through the second resistor R2, the second input terminal 212 is grounded, and the second resistor R2 absorbs the load of the second input terminal 212. The main terminal of the second single-pole double-throw switch S4 connects to the second moving terminal of the second single-pole double-throw switch S4. Since the second moving terminal of the second single-pole double-throw switch S4 is grounded through the fourth resistor R4, the fourth input terminal 214 is grounded, and the fourth resistor R4 absorbs the load of the fourth input terminal 214. The absorption of load by the second resistor R2 and the fourth resistor R4 solves the power reflection problem and greatly improves the stability of the satellite navigation system.

[0058] Figure 8 This is a second schematic diagram of the second switch state combination provided in the embodiments of this application. For example... Figure 8As shown, the main terminal of the single-pole three-throw switch S1 is connected to the second moving terminal of the single-pole three-throw switch S1, and the main terminal of the fifth single-pole double-throw switch S7 is connected to the first moving terminal of the fifth single-pole double-throw switch S7. Since the second moving terminal of the single-pole three-throw switch S1 is connected to the first moving terminal of the fifth single-pole double-throw switch S7, the first input terminal 211 is connected to the third output terminal 223. The main terminal of the single-pole four-throw switch S3 is connected to the third moving terminal of the single-pole four-throw switch S3, and the main terminal of the sixth single-pole double-throw switch S8 is connected to the first moving terminal of the sixth single-pole double-throw switch S8. Since the third moving terminal of the single-pole four-throw switch S3 is connected to the first moving terminal of the sixth single-pole double-throw switch S8, 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 from the L1 band of the first antenna 31 and the second antenna 32 through the third output terminal 223 and the fourth output terminal 224, respectively, and can perform orientation and attitude measurement based on the signals from the L1 band of the first antenna 31 and the second antenna 32. Simultaneously, the main terminal of the first single-pole double-throw switch S2 connects to the second moving terminal of the first single-pole double-throw switch S2. Since the second moving terminal of the first single-pole double-throw switch S2 is grounded through the second resistor R2, the second input terminal 212 is grounded, and the second resistor R2 absorbs the load of the second input terminal 212. The main terminal of the second single-pole double-throw switch S4 connects to the second moving terminal of the second single-pole double-throw switch S4. Since the second moving terminal of the second single-pole double-throw switch S4 is grounded through the fourth resistor R4, the fourth input terminal 214 is grounded, and the fourth resistor R4 absorbs the load of the fourth input terminal 214. The absorption of load by the second resistor R2 and the fourth resistor R4 solves the power reflection problem and greatly improves the stability of the satellite navigation system.

[0059] In this embodiment, the third switch state combination can be as follows: the first input terminal 211 is connected to the first output terminal 221 through a single-pole triple-throw switch S1 and a third single-pole double-throw switch S5; the second input terminal 212 is connected to the second output terminal 222 through a second single-pole double-throw switch S4 and a fourth single-pole double-throw switch S6; the third input terminal 213 is connected to the third output terminal 223 through a single-pole quadruple-throw switch S3 and a fifth single-pole double-throw switch S7; and the fourth input terminal 214 is 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.

[0060] Figure 9 This is a schematic diagram of the third switch state combination provided in an embodiment of this application. For example... Figure 9As shown, the main terminal of the single-pole triple-throw switch S1 is connected to the first moving terminal of the single-pole triple-throw switch S1, and the main terminal of the third single-pole double-throw switch S5 is connected to the first moving terminal of the third single-pole double-throw switch S5. Since the first moving terminal of the single-pole triple-throw switch S1 is connected to the first moving terminal of the third single-pole double-throw switch S5, the first input terminal 211 is connected to the first output terminal 221. The main terminal of the first single-pole double-throw switch S2 is connected to the first moving terminal of the first single-pole double-throw switch S2, and the main terminal of the fourth single-pole double-throw switch S6 is connected to the first moving terminal of the fourth single-pole double-throw switch S6. Since the first moving terminal of the first single-pole double-throw switch S2 is connected to the first moving terminal of the fourth single-pole double-throw switch S6, the second input terminal 212 is connected to the second output terminal 222. The main terminal of the single-pole four-throw switch S3 is connected to the second moving terminal of the single-pole four-throw switch S3. The main terminal of the fifth single-pole double-throw switch S7 is connected to the second moving terminal of the fifth single-pole double-throw switch S7. Since the second moving terminal of the single-pole four-throw switch S3 is connected to the second moving terminal of the fifth single-pole double-throw switch S7, the third input terminal 213 is connected to the third output terminal 223. The main terminal of the second single-pole double-throw switch S4 is connected to the first moving terminal of the second single-pole double-throw switch S4. The main terminal of the sixth single-pole double-throw switch S8 is connected to the second moving terminal of the sixth single-pole double-throw switch S8. Since the first moving terminal of the second single-pole double-throw switch S4 is connected to the second moving terminal of the sixth single-pole double-throw switch S8, 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 from the L1 band and the L2 / L5 band of the first antenna 31 and the second antenna 32 respectively through the first output terminal 221, the second output terminal 222, the third output terminal 223, and the fourth output terminal 224, and can perform orientation and attitude measurement based on the signals from the L1 band and the L2 / L5 band of the first antenna 31 and the second antenna 32.

[0061] Furthermore, the second moving contact of the third single-pole double-throw switch S5 is connected to the radio frequency test interface, which allows for debugging of the receiver chip in the satellite navigation system.

[0062] It should be noted that the above describes an embodiment of multi-antenna single-frequency orientation and attitude measurement based on the L1 band signals of the first and second antennas of a satellite navigation system. If it is desired to simultaneously realize multi-antenna single-frequency orientation and attitude measurement based on the L2 / L5 band signals of the first and second antennas of a satellite navigation system, the first single-pole double-throw switch S2 can be replaced with a single-pole four-throw switch S3, and 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 can be replaced with a single-pole triple-throw switch S1 to increase the connection path between the second input terminal 212 and the first output terminal 221 and the third output terminal 223, and to increase the connection path between the fourth input terminal 214 and the second output terminal 222. Figure 10 This is a schematic diagram of another matrix switch provided in an embodiment of this application. For example... Figure 10 As shown, the second input terminal 212 is connected to the first output terminal 221, the second output terminal 222, the third output terminal 223, or ground, and the fourth input terminal 214 is connected to the second output terminal 222, the fourth output terminal 224, or ground. When the second input terminal 212 is connected to the first output terminal 221 and the fourth input terminal 214 is connected to the second output terminal 222, the first receiver chip 41 and the second receiver chip 42 can receive signals from the L2 / L5 frequency band of the first antenna 31 and the second antenna 32. When the second input terminal 212 is connected to the third output terminal 223 and the fourth input terminal 214 is connected to the fourth output terminal 224, the third receiver chip 43 and the fourth receiver chip 44 can receive signals from the L2 / L5 frequency band of the first antenna 31 and the second antenna 32.

[0063] In one embodiment, the frequency divider circuit 10 further includes 2N low-noise amplifiers. The input of each divider is connected to the output of one low-noise amplifier, and the input of each low-noise amplifier is used to connect to an antenna. The low-noise amplifier is a broadband low-noise amplifier chip that supports the operating frequency band of the satellite navigation system. The peripheral circuitry of the broadband low-noise amplifier chip is designed to match the operating frequency band to suit the satellite navigation system's operating frequency band. This embodiment describes an example where the frequency divider circuit 10 has two low-noise amplifiers. (Refer to...) Figure 3The frequency divider circuit 10 includes a first low-noise amplifier 151 and a second low-noise amplifier 152. The input terminal of the first low-noise amplifier 151 is connected to the first antenna 31, and the output terminal of the first low-noise amplifier 151 is connected to the input terminal of the first splitter 131. The input terminal of the second low-noise amplifier 152 is connected to the second antenna 32, and the output terminal of the second low-noise amplifier 152 is connected to the input terminal of the second splitter 132. While amplifying the signals received by the first antenna 31 and the second antenna 32, the first low-noise amplifier 151 and the second low-noise amplifier 152 reduce their own noise and improve the output signal-to-noise ratio, thereby ensuring that the signal link between the first antenna 31 and the second antenna 32 has a good noise system and improving the noise performance of the entire RF front-end circuit.

[0064] In one embodiment, the frequency divider circuit 10 includes 4N adjustable attenuators. The input of each adjustable attenuator is connected to the output of a filter 14, and each input 21 of the matrix switch 20 is connected to the output of an adjustable attenuator. The adjustable attenuators can be analog, digital, or low-cost Π-type or T-type resistor attenuation networks. Since the amplitude performance of devices such as low-noise amplifiers and splitters is inconsistent across different operating frequency bands (e.g., the gain and insertion loss of the L1 band and L2 / L5 band are not consistent), the accumulation of amplitude differences can severely affect the amplitude balance of the signal ultimately entering the receiver chip 40 when there are many devices in the signal link. The introduction of adjustable attenuators ensures the amplitude balance of each signal link, keeping the amplitude flatness of the signal link stable within a small range, typically within 1 dB. This embodiment describes an example with four adjustable attenuators in the frequency divider circuit 10. (Reference) Figure 3The frequency divider circuit 10 includes a first adjustable attenuator 161, a second adjustable attenuator 162, a third adjustable attenuator 163, and a fourth adjustable attenuator 164. The input terminal of the first adjustable attenuator 161 is connected to the output terminal of the first filter 141, the input terminal of the second adjustable attenuator 162 is connected to the output terminal of the second filter 142, the input terminal of the third adjustable attenuator 163 is connected to the output terminal of the third filter 143, and the input terminal of the fourth adjustable attenuator 164 is connected to the output terminal of the fourth filter 144. The first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 of the matrix switch 20 are respectively connected to the output terminals of the first adjustable attenuator 161, the second adjustable attenuator 162, the third adjustable attenuator 163, and the fourth adjustable attenuator 164. The first adjustable attenuator 161, the second adjustable attenuator 162, the third adjustable attenuator 163, and the fourth adjustable attenuator 164 can adjust the amplitude of the signals output from the first filter 141, the second filter 142, the third filter 143, and the fourth filter 144, so that the amplitude of the signals connected to the first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 is stabilized within a certain range.

[0065] In one embodiment, the frequency divider circuit 10 includes 4N variable gain amplifiers. The input of each variable gain amplifier is connected to the output of a filter 14, and each input 21 of the matrix switch 20 is connected to the output of a variable gain amplifier. The variable gain amplifiers include amplifiers with bypass functionality, analog variable gain amplifiers, and digital variable gain amplifiers. The variable gain amplifiers can adjust the gain of the frequency divider circuit 10, making the RF front-end circuit suitable for various external antennas 30. For example, when the antenna 30 gain is too high, the amplifier's bypass function can be used, or the gain of the variable gain amplifier can be reduced; when the antenna 30 gain is low, the amplifier can be turned on, or the gain of the variable gain amplifier can be increased, ensuring that the satellite navigation system can use various external antennas without being limited by the gain range of the external antennas, thus improving the dynamic range of the satellite navigation system. This embodiment describes a frequency divider circuit 10 with four variable gain amplifiers as an example. (Reference) Figure 3The frequency divider 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. The input terminal of the first variable gain amplifier 171 is connected to the output terminal of the first filter 141, the input terminal of the second variable gain amplifier 172 is connected to the output terminal of the second filter 142, the input terminal of the third variable gain amplifier 173 is connected to the output terminal of the third filter 143, and the input terminal of the fourth variable gain amplifier 174 is connected to the output terminal of the fourth filter 144. The first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 of the matrix switch 20 are respectively connected to the output terminals of the first variable gain amplifier 171, the second variable gain amplifier 172, the third variable gain amplifier 173, and the fourth variable gain amplifier 174. The first variable gain amplifier 171 and the second variable gain amplifier 172 can process the signal of the first antenna 31 to adjust the signal amplitude of the first antenna 31 to the processing range of the receiver chip. The third variable gain amplifier 173 and the fourth variable gain amplifier 174 can process the signal of the second antenna 32 so that the signal amplitude of the second antenna 32 is adjusted to the processing range of the receiver chip 40.

[0066] In one embodiment, the frequency divider circuit 10 includes 4N phase shifters. The input of each phase shifter is connected to the output of a filter 14, and each input 21 of the matrix switch 20 is connected to the output of a phase shifter. The phase shifters can be analog phase shifters, digital phase shifters, or low-cost microstrip line phase-shifting loops. Since the phase performance of devices such as low-noise amplifiers and splitters is inconsistent in different operating frequency bands, the accumulation of phase differences can severely affect the phase balance of the signal finally entering the receiver chip 40 when there are many devices in the signal link. The introduction of phase shifters can ensure the phase balance of each signal link, and the phase flatness of the signal link is kept within a small range, generally within 10°. This embodiment describes a frequency divider circuit 10 with four phase shifters as an example. (Reference) Figure 3The frequency divider 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 terminal of the first phase shifter 181 is connected to the output terminal of the first filter 141, the input terminal of the second phase shifter 182 is connected to the output terminal of the second filter 142, the input terminal of the third phase shifter 183 is connected to the output terminal of the third filter 143, and the input terminal of the fourth phase shifter 184 is connected to the output terminal of the fourth filter 144. The first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 of the matrix switch 20 are respectively connected to the output terminals of the first phase shifter 181, the second phase shifter 182, the third phase shifter 183, and the fourth phase shifter 184. The first phase shifter 181, the second phase shifter 182, the third phase shifter 183, and the fourth phase shifter 184 can adjust the phase of the signals output from the first filter 141, the second filter 142, the third filter 143, and the fourth filter 144, so that the phase of the signals input to the first input terminal 211, the second input terminal 212, the third input terminal 213, and the fourth input terminal 214 is stabilized within a certain range.

[0067] refer to Figure 3 When the frequency divider circuit 10 is equipped with an adjustable attenuator, a variable gain amplifier and a phase shifter, the filter 14, the adjustable attenuator, the variable gain amplifier and the phase shifter are connected in series on a single signal link.

[0068] In summary, the radio frequency front-end circuit provided in this application divides the signal transmitted by each antenna 30 into two frequency bands through the frequency divider circuit 10, and sends the signals of different antennas 30 in different frequency bands to different output terminals of the frequency divider circuit 10, so that the input terminal of the matrix switch 20 can be connected to the signals of multiple frequency bands transmitted by multiple antennas 30. By switching multiple switching devices within the matrix switch 20 in at least three switching state combinations, the receiver chip 40 receives single-antenna multi-frequency signals, multi-antenna single-frequency signals, and multi-antenna multi-frequency signals respectively under various switching state combinations. Based on these signals, it executes three RTK positioning algorithms: single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude measurement, and multi-antenna multi-frequency orientation and attitude measurement. This enables satellite navigation systems to perform single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude measurement using a single RF front-end circuit, significantly reducing the manufacturing cost of the RF front-end circuit, improving its integration, and minimizing its size. It solves the problems of high manufacturing cost and large size of RF front-end circuits in existing satellite navigation systems. While ensuring excellent RF performance, it achieves lower manufacturing costs and a smaller size, allowing the satellite navigation system to be applied in various scenarios and improving its applicability.

[0069] Based on the above embodiments, this application also provides a satellite navigation system, which includes an antenna 30, a receiver chip 40, and the radio frequency front-end circuit described in the above embodiments.

[0070] As described above, by incorporating the radio frequency (RF) front-end circuit described in the above embodiments into the satellite navigation system, the satellite navigation system can achieve single-antenna multi-frequency positioning, multi-antenna single-frequency orientation and attitude measurement, and multi-antenna multi-frequency orientation and attitude measurement using only one RF front-end circuit. This significantly reduces the manufacturing cost of the RF front-end circuit, improves its integration, and reduces its size. It solves the problems of high manufacturing cost and large size of RF front-end circuits in existing satellite navigation systems. While ensuring excellent RF performance, it also has low manufacturing cost and small size, allowing the satellite navigation system to be applied in various scenarios and improving its applicability.

[0071] The above description is merely a preferred embodiment and the technical principles employed in this application. This application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions that can be made by those skilled in the art will not depart from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of this application, the scope of which is determined by the scope of the claims.

Claims

1. A radio frequency front-end circuit, characterized in that, The system includes a frequency divider circuit and a matrix switch. The frequency divider circuit has at least two input terminals and at least four output terminals, and the matrix switch has at least four input terminals and at least four output terminals, wherein: The input terminal of the frequency divider circuit is used to connect to the antenna, and each output terminal of the frequency divider circuit is respectively connected to each input terminal of the matrix switch; each input terminal of the matrix switch is respectively connected to each output terminal through a switching device, and the output terminal of the matrix switch is used to connect to the receiver chip. The matrix switch contains multiple switching devices that switch between at least three switching state combinations, enabling the receiver chip to execute three RTK positioning algorithms under each combination. These three RTK positioning algorithms include a single-antenna multi-frequency positioning algorithm, a multi-antenna single-frequency orientation and attitude measurement algorithm, and a multi-antenna multi-frequency orientation and attitude measurement algorithm. Specifically, when the matrix switch is in the first switching state combination, signals from each frequency band of a single antenna are transmitted to the receiver chip, allowing the receiver chip to execute the single-antenna multi-frequency positioning algorithm based on the received signals. When the matrix switch is in the second switching state combination, signals from the same frequency band of each antenna are transmitted to the receiver chip, enabling the receiver chip to execute the multi-antenna single-frequency orientation and attitude measurement algorithm based on the received signals. When the matrix switch is in the third switching state combination, signals from each frequency band of each antenna are transmitted to the receiver chip, enabling the receiver chip to execute the multi-antenna multi-frequency orientation and attitude measurement algorithm based on the received signals.

2. The radio frequency front-end circuit according to claim 1, characterized in that, The frequency divider circuit includes 2N splitters and 4N filters, and the matrix switch includes 4N input terminals and 4N output terminals, where N is a positive integer greater than or equal to 1. Each of the splitters has an input terminal connected to an antenna, and the input terminals of every two filters are connected to the output terminal of the splitter. Each input terminal of the matrix switch is connected to the output terminal of a filter. The splitter is used to split the signal input to the corresponding antenna into two signals and send them to the corresponding connected filters. Two filters connected to the same splitter are used to filter signals of different frequency bands.

3. The radio frequency front-end circuit according to claim 2, characterized in that, The frequency divider circuit includes a first splitter, a second splitter, a first filter, a second filter, a third filter, and a fourth filter. The matrix switch includes four input terminals and four output terminals, wherein: The input terminal of the first splitter is used to connect to the first antenna, and the output terminal of the first splitter is connected to the input terminal of the first filter and the input terminal of the second filter; the input terminal of the second splitter is used to connect to the second antenna, and the output terminal of the second splitter is connected to the input terminal of the third filter and the input terminal of the fourth filter; the four input terminals of the matrix switch are respectively connected to the output terminals of the first filter, the second filter, the third filter, and the fourth filter, and the four output terminals of the matrix switch are respectively used to connect to the first receiver chip, the second receiver chip, the third receiver chip, and the fourth receiver chip; The first filter and the third filter are used to filter signals outside the first frequency band, and the second filter and the fourth filter are used to filter signals outside the second frequency band.

4. The RF front-end circuit according to claim 3, wherein the first receiver chip and the second receiver chip are receiver chips of a first type, and the third receiver chip and the fourth receiver chip are receiver chips of a second type, wherein: When the matrix switch is in the first switch state combination, the 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 transmitted to the third receiver chip and the fourth receiver chip, respectively, 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.

5. The RF front-end circuit according to claim 3, wherein the first receiver chip and the second receiver chip are receiver chips of a first type, and the third receiver chip and the fourth receiver chip are receiver chips of a second type, wherein: When the matrix switch is in the second switch state combination, the signals of the first frequency band of the first antenna and the second 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 multi-antenna single-frequency positioning algorithm based on the received signals to obtain a first orientation measurement result; the signals of the first frequency band of the first antenna and the second antenna are transmitted to the third receiver chip and the fourth receiver chip, respectively, 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 measurement result; the first orientation measurement result and the second orientation measurement result are used to test the orientation measurement performance of the first type of receiver chip and the second type of receiver chip.

6. The radio frequency front-end circuit according to claim 2, characterized in that, The frequency divider circuit includes 4N adjustable attenuators, the input of each adjustable attenuator is connected to the output of one of the filters, and each input of the matrix switch is connected to the output of one of the adjustable attenuators.

7. The radio frequency front-end circuit according to claim 2, characterized in that, The frequency divider circuit includes 4N variable gain amplifiers, the input of each variable gain amplifier is connected to the output of one of the filters, and the input of each matrix switch is connected to the output of one of the variable gain amplifiers.

8. The radio frequency front-end circuit according to claim 2, characterized in that, The frequency division circuit includes 4N phase shifters, the input of each phase shifter is connected to the output of one of the filters, and the input of each matrix switch is connected to the output of one of the phase shifters.

9. A satellite navigation system, characterized in that, include: Antenna, receiver chip, and radio frequency front-end circuit as described in any one of claims 1-8.

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