Signal transmission methods, devices, and electronic equipment for terminal positioning

Abstract

The application discloses a signal transmission method, device and electronic equipment for terminal positioning. The signal transmission method comprises the following steps: aligning the starting moment of each bit navigation text information in a navigation text with the moment when a transmitter is turned on to start transmission, and aligning the ending moment of the same bit navigation text information with the moment when the transmitter is turned on to start the next transmission; setting a target period for transmitting the navigation text, wherein the target period is smaller than a transmission period, and the target period is within the transmission period; modulating the navigation text based on binary phase shift keying, and transmitting the modulated navigation text at a set power in the target period; if the data value of the navigation text is 1, the set power is equal to the peak power; if the data value of the navigation text is 0, the set power is smaller than the peak power. The method combines phase modulation and amplitude modulation, can be compatible with different terminal demodulation schemes, and enables the terminal to demodulate the text in a complex scene.

Description

Technical Field

[0001] This application relates to the field of positioning technology, and in particular to a signal transmission method, apparatus and electronic device for terminal positioning. Background Technology

[0002] The Global Positioning System (GPS), a high-precision radio navigation and positioning system based on artificial Earth satellites, has been widely used in navigation, surveying, and timing. The system typically consists of multiple navigation satellites distributed in space and ground-based user terminals. Each navigation satellite is equipped with a pseudo-random code that identifies it. This code is used to perform direct sequence spread spectrum processing on the baseband signal, and then modulates the spread signal onto a radio frequency carrier to generate a time-continuous positioning signal, which is continuously transmitted back to the ground.

[0003] However, the positioning signal is extremely weak after it propagates through the atmosphere to the user terminal on the ground. Although direct sequence spread spectrum can bring certain spread spectrum gain, it leads to insufficient demodulation capability of the terminal in some complex scenarios. Moreover, due to the differences in demodulation schemes of different terminals, demodulation can easily lead to an increase in the bit error rate of the terminal, affecting the positioning accuracy of the terminal. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this application is to provide a signal transmission method, apparatus and electronic device for terminal positioning, which is compatible with different terminal demodulation schemes and enables the terminal to demodulate messages in complex scenarios.

[0005] To achieve the above objectives, this application adopts the following technical solution: In a first aspect, embodiments of this application provide a signal transmission method for terminal positioning, comprising: Align the start time of each bit of navigation message information in the navigation message with the time when the transmitter starts transmitting, and align the end time of the same bit of navigation message information with the time when the transmitter starts the next transmission. Set the target time period for transmitting navigation messages. The target time period is shorter than the transmitter's transmission time period and is within the transmission time period. The transmission time period represents the time interval between when the transmitter turns on the transmission state and when it turns off the transmission state. The navigation message is based on binary phase shift modulation and is transmitted at a set power during the target time period. If the data value of the navigation message is 1, then the power setting is equal to the peak power; If the data value of the navigation message is 0, then the power setting is less than the peak power.

[0006] In some embodiments, if the data value of the navigation message is 0, the power is set to at least 1 / 2 of the peak power.

[0007] The signal transmission method provided in this embodiment sets a target time period for transmitting the navigation message, ensuring that the target time period is shorter than the transmitter's transmission time period and falls within the transmission time period. When the data value of the navigation message is 1, the transmitter transmits each bit of the navigation message at peak power; when the data value of the navigation message is 0, the transmitter transmits each bit of the navigation message at a power lower than peak power. This allows the terminal to correctly demodulate the navigation message by recognizing signal power changes without needing to lock the carrier phase, adapting to more complex scenarios. Furthermore, the above method combines phase modulation and amplitude modulation, making it compatible with different terminal demodulation schemes and enabling the terminal to demodulate the navigation message in complex scenarios.

[0008] In some embodiments, the target time period is set to T / 2-3T / 4 after the transmitter is turned on, where T represents the transmission time period.

[0009] In some embodiments, the signal transmission method further includes: Set a regular time period for transmitting navigation messages, where the sum of the regular time period and the target time period equals the transmission time period; If the data value of the navigation message is 1 during a transmission period, the set power is equal to the peak power in both the target period and the normal period. If the data value of the navigation message is 0 during a transmission period, the set power is less than the peak power during the target period, and the set power is equal to the peak power during the normal period.

[0010] In some embodiments, the navigation message is related to the transmitter's signal amplitude and carrier phase, with the signal amplitude used to adjust the set power.

[0011] In some embodiments, the positioning signal modulated from the navigation message satisfies the following relationship: ; In the formula, S t Indicates the positioning signal; A represents the transmitter signal amplitude; j represents the imaginary unit; f c The carrier frequency of the transmitter is represented by t; the time variable is represented by ψ; and the carrier phase is represented by ψ. The positioning signal is decarrier-reduced based on the carrier estimation frequency set by the terminal to obtain the decarrier-reduced baseband signal; the decarrier-reduced baseband signal satisfies the following relationship: ; In the formula, S r This represents the baseband signal after carrier removal.

[0012] The terminal performs amplitude and phase demodulation based on the magnitude of the baseband signal after carrier removal and the carrier phase.

[0013] In some embodiments, the navigation message is modulated based on binary phase shift modulation, and the modulated navigation message is transmitted at a set power during a target time period, including: Modulated navigation messages are generated by N transmitters deployed in the target area; Each transmitter operates in turn according to a preset transmission sequence. At any given time, only one transmitter is in the signal transmission enabled state, while the rest are in the signal transmission disabled state. Each transmitter performs the transmission operation in a cyclical manner from the 1st to the Nth transmitter. In each cycle, each transmitter transmits one bit of navigation message information corresponding to its navigation message in turn.

[0014] Secondly, embodiments of this application also provide a signal transmitting device for terminal positioning, comprising: The transmitter is used to align the moment it turns on the transmission state with the start time of each bit of navigation message information in the navigation message, and to align the moment it turns off the transmission state with the end time of one bit of navigation message information. The transmitter sets a target time period for transmitting navigation messages. The target time period is shorter than the transmitter's transmission time period, and the target time period is within the transmission time period. The transmission time period represents the time interval between when the transmitter turns on the transmission state and when it turns off the transmission state. The transmitter modulates the navigation message based on binary phase shift and transmits the modulated navigation message at a set power during the target time period; if the data value of the navigation message is 1, the set power is equal to the peak power; if the data value of the navigation message is 0, the set power is less than the peak power.

[0015] Thirdly, embodiments of this application also provide an electronic device, which includes a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the signal transmission method in the first aspect.

[0016] Fourthly, embodiments of this application also provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, implements the signal transmission method of the first aspect. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the first hardware architecture of the signal transmission method in the embodiments of this application; Figure 2 This is a schematic diagram of a second hardware architecture for the signal transmission method in the embodiments of this application; Figure 3This is a flowchart of the signal transmission method in the embodiments of this application; Figure 4 This is a timing diagram of the transmitter transmitting one bit of navigation message information in an embodiment of this application; Figure 5 This is a timing diagram of multiple transmitters transmitting navigation messages in a time-division manner in an embodiment of this application; Figure 6 This is a flowchart illustrating the time-division multiple transmitters transmitting navigation messages in an embodiment of this application. Figure 7 This is a schematic diagram of an electronic device in an embodiment of this application. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

[0019] It should be noted that the terms "first," "second," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. "A plurality" or "several" indicates at least two. "Comprising" or "including" and similar terms mean that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude other elements or objects. "Connected" or "linked" and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect.

[0020] like Figure 1As shown, this application provides a signal transmission method for terminal positioning. In one embodiment, the signal transmission method can be applied to a ground-based signal transmission device 100, which is used in conjunction with navigation satellites 200 distributed in space. Each navigation satellite 200 is equipped with a pseudo-random code that uniquely identifies itself. During signal transmission, each navigation satellite 200 uses its own pseudo-random code to perform direct sequence spread spectrum on the baseband signal and modulates the spread signal onto a radio frequency carrier to generate a time-continuous positioning signal, which is continuously transmitted to the ground. The signal transmission device 100 includes a receiver 11, a signal processing device 12, and a transmitter 13. The receiver 11 receives the positioning signal and sends it to the signal processing device 12. The signal processing device 12 can calculate the current position of the signal transmission device 100 based on the positioning signal and modulate the information indicating the current position of the signal transmission device 100 into a navigation message that can be interpreted by the terminal 300, which is then transmitted to the terminal 300 via the transmitter 13. When transmitting a navigation message, transmitter 13 performs the method steps described in the following embodiments.

[0021] like Figure 2 As shown, in another embodiment, this signal transmission method can be applied to a signal transmitting device 100, which acts as a "pseudo-satellite" and is equipped with a pseudo-random code that uniquely identifies itself. During signal transmission, the signal transmitting device 100 uses its own pseudo-random code to perform direct sequence spread spectrum on the baseband signal and modulates the spread signal onto a radio frequency carrier to generate a time-continuous positioning signal, which is then transmitted to the terminal 300 via transmitter 13. When transmitting navigation messages, transmitter 13 executes the method steps described in the following embodiments.

[0022] like Figure 3 As shown, this application provides a signal transmission method for terminal positioning, which includes: Step S101: Align the start time of each bit of navigation message information in the navigation message with the time when the transmitter 13 starts transmitting, and align the end time of the same bit of navigation message information with the time when the transmitter 13 starts the next transmission state.

[0023] like Figure 4 As shown, the transmitter 13 starts transmitting at time t0. Before transmitting one bit of navigation message information in the navigation message, the transmitter 13 aligns the start time of the navigation message to time t0. The transmitter 13 stops transmitting at time t4, and the transmitter 13 aligns the end time of transmitting the navigation message to time t4.

[0024] In some embodiments, multiple transmitters 13 can be deployed in the target area, and each transmitter 13 takes turns working in a time-division manner. At any given time, only one transmitter 13 is in the transmission state, while the other transmitters 13 are in the transmission state, thereby avoiding mutual interference and power loss caused by the superposition of multiple signal powers.

[0025] like Figure 5 As shown, taking N transmitters 13 as an example, the start time of each bit of navigation message information in the navigation message transmitted by transmitter 1 is aligned with the time when transmitter 1 starts transmitting, and the end time of the same bit of navigation message information is aligned with the time when transmitter 1 starts the next transmission. Since the time when transmitter 1 starts the next transmission coincides with the time when transmitter N stops transmitting, the end time of each bit of navigation message information in the navigation message transmitted by transmitter 1 is simultaneously aligned with the time when transmitter N stops transmitting. Similarly, the start time of each bit of navigation message information in the navigation messages transmitted by transmitters 2 to N is aligned with the time when transmitter 1 starts transmitting, and the end time of each bit of navigation message information transmitted by transmitters 2 to N is aligned with the time when transmitter N stops transmitting.

[0026] Step S102: Set the target time period for transmitting navigation messages.

[0027] The target time period is shorter than the launch time period of transmitter 13, and the target time period is within the launch time period; the launch time period represents the time interval between when transmitter 13 turns on the launch state and when it turns off the launch state.

[0028] Step S103: Modulate the navigation message based on binary phase shift and transmit the modulated navigation message at a set power during the target time period.

[0029] like Figure 4 As shown, in this embodiment, if the data value of the navigation message is 1, the set power is equal to the peak power; if the data value of the navigation message is 0, the set power is less than the peak power.

[0030] In some embodiments, if the data value of the navigation message is 0, the set power is at least half of the peak power. On one hand, setting the power to half of the peak power when the data value of the navigation message is 0 facilitates signal modulation by the transmitter 13. On the other hand, since the transmit power of the transmitter 13 follows a square law relationship with the signal amplitude, i.e., P∝V... 2 When transmitter 13 sets the power of the data value representing the navigation message to 0 to the peak power... At that time, the corresponding voltage amplitude is only the peak amplitude. The dynamic range of the analog-to-digital converter (ADC) in Terminal 300 is typically calibrated based on peak power. In this case, the effective quantization bits of the navigation message will be reduced accordingly when the data value is 0. If the power is set to the peak power... Then the quantization bit loss is 1 bit. If the power is set to the peak power... If the quantization bit width is reduced by 2 bits, the quantization noise floor will be directly increased and the resolution of small signals will be weakened. Therefore, in this embodiment, the set power is set to not less than 1 / 2 of the peak power, which can effectively reduce the average transmit power of the transmitter 13, thereby reducing multiple access interference and improving the acquisition and tracking performance of the terminal 300 in weak signal environments. In addition, the analog-to-digital converter of the terminal 300 can effectively reduce the loss of quantization bit width.

[0031] In some embodiments, the target time period is set to T / 2-3T / 4 after the transmitter 13 starts transmitting, where T represents the transmission time period.

[0032] like Figure 4 As shown, in this embodiment, the target time period is from time t2 to time t3 when the transmitter 13 is in the transmit-on state.

[0033] In some embodiments, the transmitter 13 is further configured with a regular time period for transmitting navigation messages. The sum of the regular time period and the target time period equals the transmission time period.

[0034] like Figure 4 As shown, in this embodiment, a transmission period of the transmitter is T. The period from t2 to t3 when the transmitter 13 is in the transmission-on state is the target period. The periods from t0 to t2 and from t3 to t4 when the transmitter 13 is in the transmission-on state are both regular periods.

[0035] Specifically, within a transmission period T, if the data value of the navigation message is 1, then the set power is equal to the peak power in both the target period and the normal period. Within a transmission period T, if the data value of the navigation message is 0, then the set power is less than the peak power in the target period, and equal to the peak power in the normal period.

[0036] In some embodiments, the navigation message is related to the signal amplitude and carrier phase of the transmitter 13, and the signal amplitude is used to adjust the set power.

[0037] Specifically, the positioning signal after modulation of the navigation message satisfies the following relationship: ; In the formula, S t Indicates the positioning signal; A represents the signal amplitude of transmitter 13; e represents the base of the natural logarithm; j represents the imaginary unit; f cψ represents the carrier frequency of transmitter 13; t represents the time variable; and ψ represents the carrier phase. If the data value of the navigation message is 0, then ψ = 0, the signal amplitude during the target period is greater than 0 and less than the signal amplitude corresponding to the peak power; the signal amplitude during the normal period is equal to the signal amplitude corresponding to the peak power.

[0038] If the data value of the navigation message is 1, then ψ=π, the signal amplitude during the target period is equal to the signal amplitude corresponding to the peak power; the signal amplitude during the normal period is equal to the signal amplitude corresponding to the peak power.

[0039] The positioning signal is decarrier-decarriered based on the carrier estimation frequency set by terminal 300 to obtain the decarrier-decarrier baseband signal. Terminal 300 then performs amplitude demodulation and phase demodulation based on the magnitude and carrier phase of the decarrier-decarrier baseband signal.

[0040] The baseband signal after carrier removal satisfies the following relationship: ; In the formula, S r This represents the baseband signal after carrier removal.

[0041] Through the above settings, a flexible and reconfigurable modulation and demodulation scheme is constructed, enabling the terminal 300 to form two independent observation methods for amplitude demodulation and phase demodulation of navigation messages under the same model. Navigation messages transmitted based on this signal transmission method have higher hardware compatibility with different terminals 300.

[0042] like Figure 5 and Figure 6 As shown, in some embodiments, navigation messages are modulated based on binary phase shift modulation, and the modulated navigation messages are transmitted at a set power during a target time period, including: Step S201: Generate modulated navigation messages based on the N transmitters 13 deployed in the target area; Step S202: Each transmitter 13 takes turns operating according to the preset transmission sequence.

[0043] At any given time, only one transmitter 13 is in the signal transmission enabled state, while the rest of the transmitters 13 are in the signal transmission disabled state. Therefore, there is no mutual interference or power loss caused by the superposition of multiple signal powers.

[0044] Step S203: Each transmitter 13 performs the transmission operation in a cyclical manner from the 1st to the Nth transmitter. In each cycle, each transmitter 13 transmits one bit of navigation message information of its corresponding navigation message in turn.

[0045] Based on the same concept, this application also provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the signal transmission method in any of the above method embodiments.

[0046] like Figure 7 As shown, in one embodiment, an electronic device is provided, including a memory and a processor. The electronic device may be a terminal 300. The electronic device includes a processor, memory, a communication interface, a display screen, and an input device connected via a system bus. The processor of the electronic device provides computing and control capabilities. The memory of the electronic device includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The communication interface of the electronic device is used for wired or wireless communication with an external terminal 300. Wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements the signal transmission method in any of the above method embodiments. The display screen of the electronic device may be a liquid crystal display screen or an electronic ink display screen. The input device of the electronic device may be a touch layer covering the display screen, or buttons, a trackball, or a touchpad provided on the casing of the electronic device, or an external keyboard, touchpad, or mouse, etc.

[0047] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the electronic device to which the present application is applied. The specific electronic device may include more or fewer components than shown in the figure, or combine certain components, or have different component arrangements.

[0048] Based on the same concept, this application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the signal transmission method in any of the above method embodiments.

[0049] The aforementioned computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory, electrically erasable programmable read-only memory, erasable programmable read-only memory, programmable read-only memory, read-only memory, magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0050] Optionally, a readable storage medium can be coupled to the processor, enabling the processor to read information from and write information to the readable storage medium. Alternatively, the readable storage medium can be an integral part of the processor. The processor and the readable storage medium can reside in application-specific integrated circuits (ASICs). Of course, the processor and the readable storage medium can also exist as discrete components in the device.

[0051] The computer-readable storage medium provided in the above embodiments can be used to implement the signal transmission method in any of the above method embodiments. The implementation principle and technical effect are similar, and will not be repeated here.

[0052] Based on the same concept, this application also provides a computer program product that, when run on a computer, causes the computer to execute the signal transmission method in any of the foregoing method embodiments.

[0053] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A signal transmission method for terminal positioning, characterized in that, include: Align the start time of each bit of navigation message information in the navigation message with the time when the transmitter starts the transmission state, and align the end time of the same bit of the navigation message with the time when the transmitter starts the next transmission state. A target time period for transmitting the navigation message is set, wherein the target time period is shorter than the transmission time period of the transmitter, and the target time period is within the transmission time period; The transmission period refers to the time interval between when the transmitter turns on the transmission state and when it turns off the transmission state; The navigation message is modulated using binary phase shift modulation, and the modulated navigation message is transmitted at a set power during the target time period; If the data value of the navigation message is 1, then the set power is equal to the peak power; If the data value of the navigation message is 0, then the set power is less than the peak power.

2. The signal transmission method according to claim 1, characterized in that, If the data value of the navigation message is 0, then the set power is at least 1 / 2 of the peak power.

3. The signal transmission method according to claim 1, characterized in that, The target time period is set to T / 2-3T / 4 after the transmitter starts the transmission state, where T represents the transmission time period.

4. The signal transmission method according to claim 1, characterized in that, The signal transmission method further includes: A regular time period for transmitting the navigation message is set, wherein the sum of the regular time period and the target time period is equal to the transmission time period; If the data value of the navigation message is 1 during a transmission period, then the set power is equal to the peak power in both the target period and the normal period. If the data value of the navigation message is 0 during a certain transmission period, the set power is less than the peak power during the target period, and the set power is equal to the peak power during the normal period.

5. The signal transmission method according to claim 1, characterized in that, The navigation message is related to the signal amplitude and carrier phase of the transmitter, and the signal amplitude is used to adjust the set power.

6. The signal transmission method according to claim 5, characterized in that, The positioning signal after modulation of the navigation message satisfies the following relationship: ; In the formula, S t The location signal is represented by A; the signal amplitude of the transmitter is represented by e; the base of the natural logarithm is represented by j; the imaginary unit is represented by f. c The carrier frequency of the transmitter is represented; t represents the time variable; and ψ represents the carrier phase. The positioning signal is decarrier-reduced based on the carrier estimation frequency set by the terminal to obtain the decarrier-reduced baseband signal; the decarrier-reduced baseband signal satisfies the following relationship: ; In the formula, S r This refers to the baseband signal after carrier removal; The terminal performs amplitude and phase demodulation based on the magnitude of the baseband signal after carrier removal and the carrier phase.

7. The signal transmission method according to claim 1, characterized in that, The navigation message is modulated based on binary phase shift, and the modulated navigation message is transmitted at a set power during the target time period, including: The modulated navigation message is generated by N transmitters deployed in the target area; Each of the transmitters operates in turn according to a preset transmission sequence, wherein at any given time only one transmitter is in the signal transmission on state, while the other transmitters are in the signal transmission off state; Each of the transmitters performs the transmission operation in a cyclical manner from the first to the Nth transmitter. In each cycle, each transmitter transmits one bit of the navigation message corresponding to it.

8. A signal transmitting device for terminal positioning, characterized in that, include: A transmitter, configured to align the moment it turns on the transmission state with the start time of each bit of navigation message information in the navigation message, and to align the moment it turns off the transmission state with the end time of one bit of the navigation message; The transmitter is set to a target time period for transmitting the navigation message, the target time period being shorter than the transmitter's transmission time period, and the target time period being within the transmission time period; The transmission period refers to the time interval between when the transmitter turns on the transmission state and when it turns off the transmission state; The transmitter modulates the navigation message based on binary phase shift and transmits the modulated navigation message at a set power during the target time period; if the data value of the navigation message is 1, the set power is equal to the peak power; if the data value of the navigation message is 0, the set power is less than the peak power.

9. An electronic device, characterized in that, The device includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor causes the processor to perform the signal transmission method as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed, it implements the signal transmission method as described in any one of claims 1-7.

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