CN111123692B - An Embedded Time Unified System Based on IRIG-B Code - Google Patents

An Embedded Time Unified System Based on IRIG-B Code Download PDF

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CN111123692B
CN111123692B CN201911195120.0A CN201911195120A CN111123692B CN 111123692 B CN111123692 B CN 111123692B CN 201911195120 A CN201911195120 A CN 201911195120A CN 111123692 B CN111123692 B CN 111123692B
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irig
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CN111123692A (en
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吕冰
李文杰
陈路
郭权
刘肖姬
倪枫
韩逸飞
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Beijing Microelectronic Technology Institute
Mxtronics Corp
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    • GPHYSICS
    • G04HOROLOGY
    • G04RRADIO-CONTROLLED TIME-PIECES
    • G04R20/00Setting the time according to the time information carried or implied by the radio signal
    • G04R20/02Setting the time according to the time information carried or implied by the radio signal the radio signal being sent by a satellite, e.g. GPS
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13Receivers
    • G01S19/24Acquisition or tracking or demodulation of signals transmitted by the system
    • G01S19/25Acquisition or tracking or demodulation of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS
    • G01S19/256Acquisition or tracking or demodulation of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS relating to timing, e.g. time of week, code phase, timing offset
    • GPHYSICS
    • G04HOROLOGY
    • G04RRADIO-CONTROLLED TIME-PIECES
    • G04R20/00Setting the time according to the time information carried or implied by the radio signal
    • G04R20/02Setting the time according to the time information carried or implied by the radio signal the radio signal being sent by a satellite, e.g. GPS
    • G04R20/04Tuning or receiving; Circuits therefor

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  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
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Abstract

本发明提供的基于IRIG‑B码的嵌入式时间统一系统中,时间提取模块可以接收外部天线接收到的GPS及北斗信号的ZDA格式时间消息,用于提取出有效时间信息并传输给时间整合模块,时间整合模块接收到有效的时间信息,转换为8421BCD码的天、月、日、时、分、秒,并计算出TOD时间,B码转换模块,将得到的上述指定格式的时间信息根据IRIG‑B码的格式要求进行转换,并加载TOD时间,将得到的最终携带时间信息的IRIG‑B码信号传输给总控输出模块。总控输出模块显示时间信息、时区信息及信号源信息,还可以输出携带时间信息的IRIG‑B码信号。本发明用以克服现有时间统一系统方案设计中成本高昂、信号单一、不易调试等缺陷。

Figure 201911195120

In the embedded time unification system based on IRIG-B code provided by the present invention, the time extraction module can receive the ZDA format time messages of GPS and Beidou signals received by the external antenna, and is used to extract valid time information and transmit it to the time integration module , the time integration module receives the valid time information, converts it into the day, month, day, hour, minute and second of the 8421BCD code, and calculates the TOD time. The B code conversion module will obtain the time information in the above specified format according to the IRIG The format of the ‑B code needs to be converted, and the TOD time is loaded, and the obtained IRIG‑B code signal carrying the time information is transmitted to the master control output module. The master control output module displays time information, time zone information and signal source information, and can also output IRIG‑B code signals carrying time information. The present invention is used to overcome the defects of high cost, single signal, difficult debugging and the like in the scheme design of the existing time unified system.

Figure 201911195120

Description

Embedded time unified system based on IRIG-B code
Technical Field
The invention relates to an IRIG-B code-based embedded time unification system, and belongs to the field of navigation.
Background
The time unification system is provided aiming at the needs of military affairs and navigation experiments, however, in the modern communication industry, the information transmission speed is faster and faster, the requirement of high-speed digital communication on time unification is increased day by day, and in the navigation field, the importance of the time unification system is self-evident, and the requirement of the navigation system on time is extremely accurate so as to ensure the time consistency between a subsystem and a main system.
The GNSS systems commonly used at present include the GPS system in the united states, the beidou system in china, the GLONASS in russia, and GALILEO in europe, and the signal source of the current time unification system is also selected from the three. The current time unification system has a single signal source, and when the signal of the single signal source is unreliable under a specific condition, information updating needs to be carried out by conversion among different signal sources. For a time-love-you-unification system, there are many kinds of external clock sources commonly used at present, such as atomic clocks, which results in a very expensive system cost and is not beneficial to excessive production.
Disclosure of Invention
The purpose of the invention is: the invention provides an IRIG-B code-based embedded time unification system, which is used for overcoming the defects of high cost, single signal, difficulty in debugging and the like in the design of the conventional time unification system scheme.
The above purpose of the invention is mainly realized by the following technical scheme: an IRIG-B code-based embedded time unification system comprises: the system comprises a time extraction module, a time integration module, a B code conversion module and a master control output module;
the time extraction module comprises a dual-system GNSS positioning module and an extraction module, wherein the dual-system GNSS positioning module receives ZDA (zero crossing data acquisition) format time information of GPS (global positioning system) and Beidou signals received by an external antenna, and sends the ZDA format time information to an FPGA (field programmable gate array) of the extraction module through UART1 (universal asynchronous receiver transmitter) of the dual-system GNSS positioning module, the FPGA processes all data, extracts and outputs effective time information, and transmits the ASCII (American standard code for information interchange) code time information to the time integration module;
the time integration module is used for receiving the time information extracted by the time extraction module, converting the time information into days, months, days, hours, minutes and seconds of the 8421BCD code, calculating TOD time, transmitting the time information of the 8421BCD code to the B code conversion module, and outputting decimal time information to the master control output module for display;
the B code conversion module is used for converting the time information in the specified format obtained from the time integration module according to the format requirement of the IRIG-B code, loading the TOD time and outputting the signals through an external interface of the master control output module;
the master control output module provides a display information part and an output interface part for the time extraction module, the time integration module and the B code conversion module; the display information part displays time information, time zone information and signal source information; the output interface part outputs an IRIG-B code signal, an IRIG-B code signal and a 1PPS signal.
The dual-system GNSS positioning module provides real-time, observes a constellation diagram and a track diagram, receives a standard clock pulse signal 1PPS and transmits the clock pulse signal to the B code conversion module, and the dual-system GNSS positioning module also outputs the clock standard signal 1PPS to the master control output module for debugging.
And the time integration module obtains more time information through a plurality of time processing functions and outputs the time information according to the system requirements.
The B code conversion module also receives the 1PPS signal transmitted by the time extraction module for subsequent signal processing.
And the master control output module is also used for realizing a time calibration function and calculating and displaying the time difference between the time of the host and the real-time of the GPS and Beidou signals.
An IRIG-B code-based embedded time unification system further comprises: the signal interconnection module is connected with the time extraction module, the time integration module and the B code conversion module, realizes signal transmission and output and monitors signal transmission among the modules; the signal interconnection module comprises a radio frequency line, an I2C bus; the time extraction module is connected with the time integration module and the B code conversion module through RS 232-RS 422 serial port buses, and the time extraction module, the time integration module and the B code conversion module are connected with the master control output module through I2C buses.
Compared with the prior art, the invention has the following beneficial effects:
(1) in the embedded time unification system based on the IRIG-B code, the time information transmitted by two signal sources is processed and integrated to obtain required data, the time information is subjected to post-processing conversion, and the time code information of the IRIG-B code of the GPS and Beidou signals is output for use of users;
(2) the embedded time unification system based on the IRIG-B code divides the whole time unification system into four modules according to functions, the master control output module is used for controlling the output of each module, different modules can be independently debugged, and simultaneously, the processing results of the data can be output by different modules;
(3) the embedded time unification system positioning module based on the IRIG-B code provided by the invention adopts a GNSS module with low cost and low power consumption, the time integration module and the B code conversion module adopt an FPGA to complete the processes of data processing, B code conversion and the like, and the embedded time unification system positioning module also has the advantages of low cost, less energy consumption, large capacity, small size and the like.
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FIG. 1 is a schematic structural diagram of an IRIG-B code-based embedded time unification system provided by the present invention;
fig. 2 is a specific structural diagram of the IRIG-B code-based embedded time unification system provided by the present invention.
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
The invention provides an IRIG-B code-based embedded time unification system, as shown in figure 1, comprising: the system comprises a time extraction module, a time integration module, a B code conversion module and a master control output module.
The time extraction module can receive ZDA format time information of GPS and Beidou signals received by an external antenna and is used for extracting and outputting effective time information; the time extraction module comprises a dual-system GNSS positioning module and an extraction module, wherein the dual-system GNSS positioning module receives ZDA (zero crossing data acquisition) format time information of GPS (global positioning system) and Beidou signals received by an external antenna, and sends the ZDA format time information to an FPGA (field programmable gate array) of the extraction module through UART1 (universal asynchronous receiver transmitter) of the dual-system GNSS positioning module, the FPGA processes all data, extracts and outputs effective time information, and transmits the ASCII (American standard code for information interchange) code time information to the time integration module;
the time integration module is used for receiving effective time information, converting the effective time information into days, months, days, hours, minutes and seconds of 8421BCD codes, calculating TOD time, transmitting the time information of the 8421BCD codes to the B code conversion module, and outputting decimal time information to the master control output module for display;
the B code conversion module is used for converting the obtained time information in the specified format according to the format requirement of the IRIG-B code, loading TOD time and outputting the signals through an external interface;
the master control output module provides a display information part and an output interface part for the time extraction module, the time integration module and the B code conversion module. The display information part includes displaying: time information, time zone information and signal source information; an output interface section for outputting: IRIG-B (DC) code signal, IRIG-B (AC) code signal, and 1PPS signal.
In the embedded time unification system based on the IRIG-B code, provided by the invention, a time extraction module can receive ZDA format time information of GPS and Beidou signals received by an external antenna, is used for extracting effective time information and transmitting the effective time information to a time integration module, the time integration module receives the effective time information and converts the effective time information into days, months, days, hours, minutes and seconds of 8421BCD codes and calculates TOD time, a B code conversion module converts the obtained time information in the specified format according to the format requirement of the IRIG-B code, loads the TOD time and transmits the obtained IRIG-B code signal finally carrying the time information to a master control output module. The master control output module displays time information, time zone information and signal source information and can also output an IRIG-B code signal carrying the time information.
The dual-system GNSS positioning module provides real-time, observes a constellation diagram and a track diagram, receives a standard clock pulse signal 1PPS and transmits the clock pulse signal to the B code conversion module, and the dual-system GNSS positioning module also outputs the clock standard signal 1PPS to the master control output module for debugging.
And the time integration module obtains more time information through a plurality of time processing functions and outputs the time information according to the system requirements.
The B code conversion module also receives the 1PPS signal transmitted by the time extraction module for subsequent signal processing.
And the master control output module is also used for realizing a time calibration function and calculating and displaying the time difference between the time of the host and the real-time of the GPS and Beidou signals.
The signal interconnection module is connected with the time extraction module, the time integration module and the B code conversion module, realizes signal transmission and output and monitors signal transmission among the modules; the signal interconnection module comprises a radio frequency line, an I2C bus; the time extraction module is connected with the time integration module and the B code conversion module through RS 232-RS 422 serial port buses, and the time extraction module, the time integration module and the B code conversion module are connected with the master control output module through I2C buses.
The embedded time identity system based on the IRIG-B code can support the IRIG-B code time code information carrying time information, and can also provide 1PPS signals, real-time and other messages required by users.
In addition, after the master control output module displays the time signal output by the B code conversion module, the local time is calculated by the local crystal oscillator, and an error occurs after a certain time, so that the master control output module can also receive the updated time information of the B code conversion module again for synchronous updating, and can also correct the local time through manual control of a button; and each correction is to request the GNSS module to update the ZDA time information, extract and integrate again and update.
The embedded time unification system based on the IRIG-B code can output 1PPS signals, GPS and Beidou signal time information and IRIG-B code signals to the master control output module through the time extraction module, the time integration module and the B code conversion module, and can support the master control output module to output control signals requesting for updating instant time information to the time extraction module.
Specifically, the time integration module is further configured to convert the time signal extracted by the time extraction module from binary system to decimal system, and transmit the decimal system to the master control output module through the I2C interface. The advantage of doing so is, user of service can directly observe local real-time information to carry out data contrast through time information with after the update, in time calibrate the error, greatly improve work efficiency.
As shown in fig. 2, the master control output module includes a master control CPU and a display output interface. The time extraction module obtains given bit data and time information, sends the given bit data and the time information to the time integration module, sends a 1PPS signal to the master control output module, and the master control output module sends the B code conversion module for alignment calibration of IRIG-B codes per second, so that the falling edge of the IRIG-B code signal sent per second is strictly aligned with a clock standard signal 1PPS signal.
The above description is only for the best mode of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention.
The present invention has not been described in detail, partly as is known to the person skilled in the art.

Claims (3)

1.一种基于IRIG-B码的嵌入式时间统一系统,其特征在于,包括:时间提取模块、时间整合模块、B码转换模块、总控输出模块;1. an embedded time unified system based on IRIG-B code, is characterized in that, comprises: time extraction module, time integration module, B code conversion module, total control output module; 时间提取模块,包括双系统GNSS定位模块与提取模块,双系统GNSS定位模块接收外部天线接收到的GPS及北斗信号的ZDA格式时间信息,通过双系统GNSS定位模块的UART1发送给提取模块的FPGA,FPGA将所有数据进行处理后提取并输出有效时间信息,并将ASCII码形式的时间信息传输给时间整合模块;The time extraction module includes a dual-system GNSS positioning module and an extraction module. The dual-system GNSS positioning module receives the time information in ZDA format of GPS and Beidou signals received by the external antenna, and sends it to the FPGA of the extraction module through the UART1 of the dual-system GNSS positioning module. The FPGA extracts and outputs the valid time information after processing all the data, and transmits the time information in the form of ASCII code to the time integration module; 时间整合模块,接收时间提取模块提取出的时间信息,转换为8421BCD码的天、月、日、时、分、秒,并计算出TOD时间,并将8421BCD码的时间信息传输给B码转换模块,并将十进制的时间信息输出给总控输出模块用于显示;The time integration module receives the time information extracted by the time extraction module, converts it into days, months, days, hours, minutes and seconds of the 8421BCD code, calculates the TOD time, and transmits the time information of the 8421BCD code to the B code conversion module , and output the decimal time information to the master control output module for display; B码转换模块,将从时间整合模块得到的指定格式的时间信息根据IRIG-B码的格式要求进行转换,并加载TOD时间,将以上信号通过总控输出模块的外部接口进行输出;The B code conversion module converts the time information in the specified format obtained from the time integration module according to the format requirements of the IRIG-B code, and loads the TOD time, and outputs the above signals through the external interface of the master control output module; 总控输出模块为时间提取模块、时间整合模块和B码转换模块提供显示信息部分及输出接口部分;显示信息部分显示时间信息、时区信息及信号源信息;输出接口部分输出IRIG-B码信号、IRIG-B码信号及1PPS信号;The master control output module provides a display information part and an output interface part for the time extraction module, time integration module and B code conversion module; the display information part displays time information, time zone information and signal source information; the output interface part outputs IRIG-B code signal, IRIG-B code signal and 1PPS signal; 所述双系统GNSS定位模块提供实时时间、观察星座图、轨迹图,接收标准时钟脉冲信号1PPS传输给B码转换模块,双系统GNSS定位模块还将时钟标准信号1PPS输出给总控输出模块用于调试;The dual-system GNSS positioning module provides real-time time, observation constellation diagram, trajectory diagram, receives standard clock pulse signal 1PPS and transmits it to the B-code conversion module, and the dual-system GNSS positioning module also outputs the clock standard signal 1PPS to the master control output module for use. debugging; 所述B码转换模块还接收时间提取模块传输的1PPS信号用于后续信号处理;The B code conversion module also receives the 1PPS signal transmitted by the time extraction module for subsequent signal processing; 基于IRIG-B码的嵌入式时间统一系统还包括:信号互连模块,连接时间提取模块、时间整合模块、B码转换模块,实现信号传输和输出,监测各个模块之间的信号传输;所述信号互连模块包括射频线、I2C总线;时间提取模块与时间整合模块、时间整合模块与B码转换模块之间通过RS232转RS422串口总线相连,时间提取模块、时间整合模块、B码转换模块与总控输出模块通过I2C总线相连。The embedded time unified system based on IRIG-B code also includes: a signal interconnection module, which connects a time extraction module, a time integration module, and a B code conversion module, realizes signal transmission and output, and monitors the signal transmission between the various modules; the The signal interconnection module includes radio frequency line and I2C bus; the time extraction module and the time integration module, the time integration module and the B code conversion module are connected through the RS232 to RS422 serial port bus, and the time extraction module, the time integration module, and the B code conversion module are connected with each other. The master control output module is connected through the I2C bus. 2.根据权利要求1所述的一种基于IRIG-B码的嵌入式时间统一系统,其特征在于,所述时间整合模块,通过若干时间处理函数得到更多时间信息,根据系统需要进行输出。2. A kind of embedded time unification system based on IRIG-B code according to claim 1, is characterized in that, described time integration module obtains more time information through several time processing functions, and outputs according to system needs. 3.根据权利要求2所述的一种基于IRIG-B码的嵌入式时间统一系统,其特征在于,所述总控输出模块,还用于实现时间校准功能,计算并显示主机时间与GPS及北斗信号实时时间之间的时差。3. a kind of embedded time unification system based on IRIG-B code according to claim 2, is characterized in that, described master control output module, is also used for realizing time calibration function, calculates and displays host time and GPS and The time difference between the Beidou signal real-time time.
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