A method for complete synchronization of carrier pseudo-code phase in BeiDou-3 communication baseband processing

Abstract

The present invention provides a method for completely synchronizing carrier pseudo code phases of BeiDou-3 communication baseband processing, the method comprising the following steps: calculating the greatest common divisor of the satellite downlink data spread spectrum code rate and the intermediate frequency carrier frequency; calculating the number of spread spectrum code rate cycles in a common cycle according to the greatest common divisor and the spread spectrum code rate, and calculating the number of intermediate frequency carrier frequency cycles in a common cycle according to the greatest common divisor and the intermediate frequency carrier frequency; sequentially listing all pseudo code phases included in a common cycle and all carrier phases included in a common cycle and storing them as pseudo code phase and carrier phase data; reading the stored data as local pseudo code and local carrier phase values ​​according to the system clock Fclk, thereby realizing local pseudo code and local carrier phase synchronization. The present invention can achieve the effect of complete synchronization of carrier and pseudo code.

Description

Technical Field

[0001] The present invention relates to the field of Beidou communication technology, and in particular to a Beidou-3 carrier pseudo-code phase complete synchronization method, system, positioning device and storage medium. Background Art

[0002] The BeiDou-3 global satellite navigation system consists of 24 medium earth orbit satellites, 3 geostationary orbit satellites and 3 inclined geosynchronous orbit satellites, a total of 30 satellites. The BeiDou-3 satellite navigation system provides two service modes, namely open service and authorized service. The open service provides free positioning, speed measurement and timing services in the service area, with a positioning accuracy of meters, a timing accuracy of 50 nanoseconds, and a speed measurement accuracy of 0.2 meters per second. The authorized service provides more secure positioning, speed measurement, timing and communication services as well as system integrity information to authorized users.

[0003] The BeiDou-3 spread spectrum communication system needs to generate carrier waves and pseudo codes with the same frequency and phase locally to demodulate satellite data. The existing carrier and pseudo code generation method is to set up a separate carrier generation module and a separate pseudo code generation module, and use a local NCO (digital oscillator) module to generate local carrier waves and local pseudo codes respectively. Since the local carrier waves and local pseudo codes are generated by separate carrier generation modules and separate pseudo code generation modules respectively, the locally generated carrier waves and pseudo codes are relatively independent and need to be tracked and adjusted through a tracking loop so that the two can reach a relatively close synchronization. However, this method cannot achieve complete synchronization. Summary of the invention

[0004] Therefore, it is necessary to provide a method for completely synchronizing the carrier pseudo code phase of the BeiDou-3 communication baseband processing, which can achieve the effect of complete synchronization of the carrier and pseudo code.

[0005] The present invention provides a carrier pseudo code phase complete synchronization method for BeiDou-3 communication baseband processing, the method comprising the following steps:

[0006] Calculate the greatest common divisor of the satellite downlink data spreading code rate and the intermediate frequency carrier frequency;

[0007] Calculating the number of spread spectrum code rate cycles in a common period according to the greatest common divisor and the spread spectrum code rate, and calculating the number of intermediate frequency carrier frequency cycles in a common period according to the greatest common divisor and the intermediate frequency carrier frequency;

[0008] Listing all pseudo code phases included in a common period and all carrier phases included in a common period in sequence and storing them as pseudo code phase and carrier phase data;

[0009] The stored data is read according to the system clock Fclk as the local pseudo code and the local carrier phase value, thereby achieving the local pseudo code and the local carrier phase synchronization.

[0010] Further, the step of sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them includes:

[0011] A pseudocode phase cycle includes multiple pseudocode phase determination values ​​spaced at intervals of a first predetermined value, a carrier phase cycle includes multiple carrier phase determination values ​​spaced at intervals of a second predetermined value, and at the beginning of a common cycle, the smallest pseudocode phase determination value in a pseudocode phase cycle is equal to the smallest carrier phase determination value in a carrier phase cycle.

[0012] Furthermore, the spread spectrum code rate is 8.16 MHz, and the intermediate frequency carrier frequency is 12.24 MHz.

[0013] Furthermore, all the pseudo code phases included in a common cycle and all the carrier phases included in a common cycle are stored in the local RAM.

[0014] The present invention provides a carrier pseudo code phase complete synchronization system for BeiDou-3 communication baseband processing, the system comprising:

[0015] The first calculation module is used to calculate the greatest common divisor of the satellite downlink data spread spectrum code rate and the intermediate frequency carrier frequency;

[0016] A second calculation module is used to calculate the number of spread spectrum code rate cycles in a common period according to the greatest common divisor and the spread spectrum code rate, and to calculate the number of intermediate frequency carrier frequency cycles in a common period according to the greatest common divisor and the intermediate frequency carrier frequency;

[0017] An enumeration module, used for sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them as pseudo code phase and carrier phase data;

[0018] The reading module is used to read the stored data as the local pseudo code and the local carrier phase value according to the system clock Fclk, so as to achieve the local pseudo code and the local carrier phase synchronization.

[0019] Further, the step of sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them includes:

[0020] A pseudocode phase cycle includes multiple pseudocode phase determination values ​​spaced at intervals of a first predetermined value, a carrier phase cycle includes multiple carrier phase determination values ​​spaced at intervals of a second predetermined value, and at the beginning of a common cycle, the smallest pseudocode phase determination value in a pseudocode phase cycle is equal to the smallest carrier phase determination value in a carrier phase cycle.

[0021] Furthermore, the spread spectrum code rate is 8.16 MHz, and the intermediate frequency carrier frequency is 12.24 MHz.

[0022] Furthermore, all the pseudo code phases included in a common cycle and all the carrier phases included in a common cycle are stored in the local RAM.

[0023] The present invention provides a positioning device, which includes a processor and a memory. The memory stores a computer program, and the computer program can be executed by the processor to implement the carrier pseudo-code phase complete synchronization method of Beidou-3 communication baseband processing described below.

[0024] The present invention provides a computer storage medium storing a computer program, which can be executed by a processor to implement the carrier pseudo-code phase complete synchronization method for Beidou-3 communication baseband processing described below.

[0025] The present invention calculates the greatest common divisor of the satellite downlink data spread spectrum code rate and the intermediate frequency carrier frequency; calculates the number of spread spectrum code rate cycles in a common cycle according to the greatest common divisor and the spread spectrum code rate, and calculates the number of intermediate frequency carrier frequency cycles in a common cycle according to the greatest common divisor and the intermediate frequency carrier frequency; lists all pseudo code phases included in a common cycle and all carrier phases included in a common cycle in sequence and stores them as pseudo code phase and carrier phase data; and reads the stored data as local pseudo code and local carrier phase values ​​according to a system clock Fclk, thereby realizing local pseudo code and local carrier phase synchronization. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The method flow chart of a specific embodiment of the present invention. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0028] The present invention provides a method for completely synchronizing the carrier pseudo-code phase of BeiDou-3 communication baseband processing. The method can be applied to a positioning device. The positioning device may include a processor and a memory, wherein the memory may store a computer program for implementing the method, and the computer program can be executed by the processor to implement each step of the method.

[0029] It should be noted that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0030] The storage device can be used to store the computer program and / or module, and the processor runs or executes the computer program and / or module stored in the storage device. The storage device can mainly include a program storage area and a data storage area, wherein the program storage area can store an operating system, a program required for at least one function, etc.; the data storage area can store data created according to the use of the mobile phone, etc. In addition, the storage device can include a high-speed random access storage device, and can also include a non-volatile storage device, such as a hard disk, a memory, a plug-in hard disk, a smart memory card, a secure digital card, a flash memory card, at least one disk storage device, a flash memory device, or other non-volatile solid-state storage devices.

[0031] like Figure 1 As shown, the present invention provides a method for completely synchronizing the carrier pseudo code phase of BeiDou-3 communication baseband processing, and the method may include the following steps:

[0032] S10: Calculate the greatest common divisor of the satellite downlink data spreading code rate and the intermediate frequency carrier frequency.

[0033] In a specific implementation, the spread spectrum code rate is 8.16 MHz, and the intermediate frequency carrier frequency is 12.24 MHz. Through calculation, the greatest common divisor of the two can be obtained to be 4.08 MHz, and the corresponding least common multiple of the period is 245098 us.

[0034] S20: Calculate the number of spread spectrum code rate cycles in a common period according to the greatest common divisor and the spread spectrum code rate, and calculate the number of intermediate frequency carrier frequency cycles in a common period according to the greatest common divisor and the intermediate frequency carrier frequency.

[0035] In the above specific implementation, through calculation, the number of spread spectrum code rate periods in one common period is 2, and the number of intermediate frequency carrier frequency periods in one common period is 3.

[0036] S30: List all pseudo code phases included in a common period and all carrier phases included in a common period in sequence and store them as pseudo code phase and carrier phase data.

[0037] Specifically, a pseudocode phase cycle includes multiple pseudocode phase determination values ​​spaced at intervals of a first predetermined value, a carrier phase cycle includes multiple carrier phase determination values ​​spaced at intervals of a second predetermined value, and at the beginning of a common cycle, the minimum pseudocode phase determination value in a pseudocode phase cycle is equal to the minimum carrier phase determination value in a carrier phase cycle.

[0038] In the above specific implementation manner, the pseudo code phase and carrier phase listed in a common period may be shown in the following table:

[0039] A pseudo code phase cycle includes: 0°, 30°, 60°, 90°, 120°, 150°, 180°, 210°, 240°, 270°, 300°, 330°. Cycling 2 pseudo code phase cycles is a common cycle.

[0040] A carrier phase cycle includes: 0°, 45°, 90°, 135°, 180°, 225°, 270°, 315°. Cycling three carrier phase cycles is a common cycle. Among them, in a common cycle, the minimum pseudo code of the initial pseudo code phase cycle is equal to the minimum pseudo code of the initial carrier phase cycle, both of which are 0°.

[0041] S40: Reading the stored data as the local pseudo code and the local carrier phase value according to the system clock Fclk, thereby achieving the local pseudo code and the local carrier phase synchronization.

[0042] Optionally, all the pseudo-code phases included in a listed common cycle and all the carrier phases included in a listed common cycle may be stored in a local RAM, and the system clock Fclk reads the pseudo-code and carrier phase data in the RAM.

[0043] By using the method provided in the specific implementation manner of the present invention, the stored pseudocode and carrier phase numbers are read according to the system clock Fclk as local pseudocode and local carrier phase values, thereby achieving complete synchronization of the local pseudocode and local carrier phase, avoiding the defect of incomplete synchronization of the existing pseudocode and carrier, and achieving high-precision positioning.

[0044] A specific embodiment of the present invention further provides a carrier pseudo code phase complete synchronization system for BeiDou-3 communication baseband processing, the system comprising:

[0045] The first calculation module is used to calculate the greatest common divisor of the satellite downlink data spread spectrum code rate and the intermediate frequency carrier frequency;

[0046] A second calculation module is used to calculate the number of spread spectrum code rate cycles in a common period according to the greatest common divisor and the spread spectrum code rate, and to calculate the number of intermediate frequency carrier frequency cycles in a common period according to the greatest common divisor and the intermediate frequency carrier frequency;

[0047] An enumeration module, used for sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them;

[0048] The reading module is used to read the stored data as the local pseudo code and the local carrier phase value according to the system clock Fclk, so as to achieve the local pseudo code and the local carrier phase synchronization.

[0049] Further, the step of sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them includes:

[0050] A pseudocode phase cycle includes multiple pseudocode phase determination values ​​spaced at intervals of a first predetermined value, a carrier phase cycle includes multiple carrier phase determination values ​​spaced at intervals of a second predetermined value, and at the beginning of a common cycle, the smallest pseudocode phase determination value in a pseudocode phase cycle is equal to the smallest carrier phase determination value in a carrier phase cycle.

[0051] Furthermore, the spread spectrum code rate is 8.16 MHz, and the intermediate frequency carrier frequency is 12.24 MHz.

[0052] Furthermore, all the pseudo code phases included in a common cycle and all the carrier phases included in a common cycle are stored in the local RAM.

[0053] A specific embodiment of the present invention also provides a positioning device, which includes a processor and a memory, wherein the memory stores a computer program, and the computer program can be executed by the processor to implement the carrier pseudo-code phase complete synchronization method of Beidou-3 communication baseband processing described below.

[0054] A specific embodiment of the present invention also provides a computer storage medium, which stores a computer program. The computer program can be executed by a processor to implement the carrier pseudo-code phase complete synchronization method for Beidou-3 communication baseband processing described below.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for complete synchronization of carrier pseudo code phase for BeiDou-3 communication baseband processing, characterized in that: The method comprises the following steps: Calculate the greatest common divisor of the satellite downlink data spreading code rate and the intermediate frequency carrier frequency; Calculating the number of spread spectrum code rate cycles in a common period according to the greatest common divisor and the spread spectrum code rate, and calculating the number of intermediate frequency carrier frequency cycles in a common period according to the greatest common divisor and the intermediate frequency carrier frequency; Listing all pseudo code phases included in a common period and all carrier phases included in a common period in sequence and storing them as pseudo code phase and carrier phase data; The stored data is read according to the system clock Fclk as the local pseudo code and the local carrier phase value, thereby achieving the local pseudo code and the local carrier phase synchronization.

2. The carrier pseudo code phase complete synchronization method for BeiDou-3 communication baseband processing according to claim 1, characterized in that: The step of sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them includes: A pseudocode phase cycle includes multiple pseudocode phase determination values ​​spaced at intervals of a first predetermined value, a carrier phase cycle includes multiple carrier phase determination values ​​spaced at intervals of a second predetermined value, and at the beginning of a common cycle, the smallest pseudocode phase determination value in a pseudocode phase cycle is equal to the smallest carrier phase determination value in a carrier phase cycle.

3. The carrier pseudo code phase complete synchronization method for BeiDou-3 communication baseband processing according to claim 1 is characterized in that: The spread spectrum code rate is 8.16 MHz, and the intermediate frequency carrier frequency is 12.24 MHz.

4. The carrier pseudo code phase complete synchronization method for BeiDou-3 communication baseband processing according to claim 1 is characterized in that: All the listed pseudo code phases included in one common period and all the listed carrier phases included in one common period are stored in the local RAM.

5. A carrier pseudo code phase complete synchronization system for BeiDou-3 communication baseband processing, characterized in that: The system comprises: The first calculation module is used to calculate the greatest common divisor of the satellite downlink data spread spectrum code rate and the intermediate frequency carrier frequency; A second calculation module is used to calculate the number of spread spectrum code rate cycles in a common period according to the greatest common divisor and the spread spectrum code rate, and to calculate the number of intermediate frequency carrier frequency cycles in a common period according to the greatest common divisor and the intermediate frequency carrier frequency; An enumeration module, used for sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them as pseudo code phase and carrier phase data; The reading module is used to read the stored data as the local pseudo code and the local carrier phase value according to the system clock Fclk, so as to achieve the local pseudo code and the local carrier phase synchronization.

6. The carrier pseudo code phase complete synchronization system for BeiDou-3 communication baseband processing according to claim 5 is characterized in that: The step of sequentially listing all pseudo code phases included in a common period and all carrier phases included in a common period and storing them includes: A pseudocode phase cycle includes multiple pseudocode phase determination values ​​spaced at intervals of a first predetermined value, a carrier phase cycle includes multiple carrier phase determination values ​​spaced at intervals of a second predetermined value, and at the beginning of a common cycle, the smallest pseudocode phase determination value in a pseudocode phase cycle is equal to the smallest carrier phase determination value in a carrier phase cycle.

7. The carrier pseudo code phase complete synchronization system for BeiDou-3 communication baseband processing according to claim 5 is characterized in that: The spread spectrum code rate is 8.16 MHz, and the intermediate frequency carrier frequency is 12.24 MHz.

8. The carrier pseudo code phase complete synchronization system for BeiDou-3 communication baseband processing according to claim 5 is characterized in that: All the listed pseudo code phases included in one common period and all the listed carrier phases included in one common period are stored in the local RAM.

9. A positioning device, characterized in that: The positioning device includes a processor and a memory, the memory stores a computer program, and the computer program can be executed by the processor to implement the carrier pseudo-code phase complete synchronization method of Beidou-3 communication baseband processing as described in any one of claims 1-4.

10. A computer storage medium, characterized in that: The computer storage medium stores a computer program, which can be executed by a processor to implement the carrier pseudo-code phase complete synchronization method for Beidou-3 communication baseband processing as described in any one of claims 1-4.

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