CN201681269U - Multi-path submarine seismograph precision timer - Google Patents
Multi-path submarine seismograph precision timer Download PDFInfo
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- CN201681269U CN201681269U CN 201020272264 CN201020272264U CN201681269U CN 201681269 U CN201681269 U CN 201681269U CN 201020272264 CN201020272264 CN 201020272264 CN 201020272264 U CN201020272264 U CN 201020272264U CN 201681269 U CN201681269 U CN 201681269U
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Abstract
The utility model relates to the technical field of oceanic earthquake exploration, and provides a multi-path ocean bottom seismograph precision timer, which comprises an antistatic anti-interference shielding cabinet and circuits arranged in the shielding cabinet. The circuits comprise an MCU data processing unit, a GPS time service module, 1pps pulse output circuit, a timing measuring data output circuit, a dial, a switch power supply and a stabilized circuit. The novel ocean bottom seismograph precision timer of the utility model is used for receiving the real time information of GPS signals by the GPS time service module and outputting 1pps pulse signal to the MCU data processing unit to correct the crystal timing, can measure the triggering time of multi-path different signal sources, outputs corrected 1pps pulse signal and the timing measuring signal, reaches the time precision of 0.00001 second, is a time measuring instrument with high precision, provides accurate time measurement to the ocean bottom seismograph (OBS), and improves the detection precision and working efficiency of the ocean bottom earthquake exploration.
Description
Technical field
The utility model relates to the offshore shooting technical field, and a kind of submarine seismograph (OBS) timer that can accurately measure the multiple signals time specifically is provided.
Background technology
Along with the development of oceanographic survey technology, offshore geophysical prospecting turns to the submarine earthquake exploration from traditional offshore survey.Nowadays, the submarine earthquake exploration engineering is just progressively ripe, has become the requisite technical methods of emerging energy exploratory development such as research seabed infrastructure, marine four-dimensional oil-gas exploration, gas hydrate.
The submarine earthquake exploration engineering is divided into OBC (Ocean Bottom Cable, subsea cable) and OBS (Ocean Bottom Seismometer, submarine seismograph) exploration engineering, and the former adopts bay cable, and the latter adopts submarine seismograph.The OBS exploration engineering is that submarine seismograph is laid in the seabed, and the direct wave of bottom reflection, reflection wave, refraction wave etc. can reflect the raw data of submarine geology structure after in real time wide position angle, all-wave receiving record oceanographic research ship towing focus triggered and blow out.Chinese patent application as number of patent application 200810117385.4 discloses a kind of " seven-channel multi-functional submarine seismograph ".
The ocean navigator fix is the Fundamentals of Mathematics of any oceanographic survey.In common marine geologic survey, what navigator fix write down is earthquake source triggered time and all kinds of investigation apparatus geographic position and state etc., and time precision was generally 0.1 second.Certainly in this process, there are factor affecting such as electric appliance circuits time-delay, the accidental time-delay of system's operation, signal transmission delay, the uncertainty that causes the shot point positioning time (UTC time) of navigation system records, with respect to there being too much jitter error between true time, being embodied in accurate timing microscopic fields is a kind of " dirty " time.
Because submarine seismograph course of work performance is: " initialization-inputs entry-touch the end-collection-release recovery-time synchronized and inequalityization-Zhen Zeitigung ", carry out " Data Format Transform-data download preservation-submission field acquisition data achievement " again.The time window of this process externally is measurable, but is to finish with the self-isolation internal clocking at device interior, forms with external time to isolate, and causes the equipment time to have error in dipping between true time.
The time measurement error directly influences imaging and the explanation results that the OBS geological data is handled, and directly influences the achievement and the efficient of submarine earthquake exploration.It is to influence the principal element that the geological data processing profiles shows that high precision time is cut apart with stack.Compare with conventional OBC geological data, OBS record geological data is continuous, and its recording process is uninterrupted, so data processing need separate record, and this also is the basic demand of OBS data processing.The segmentation of OBS geological data needs precise time to demarcate, and the time of each shot point all must be accurately.A last shot point time precision can influence the segmentation of next shot point data, when the firing time precision of some points is not enough, geological data after the segmentation is beated generation, and the ripple of seismic signal that shows as reception causes the stratum to have the false appearance of a lot of tomographies to rough.In addition, when discontinuous seismic event, because the radial energy direction is not concentrated, can make the PS wave field separation be difficult to reach best, and can't carry out normal velocity pick, its result is exactly the true imaging that can't obtain the stratum.
Therefore, this time measurement error be eliminate, the synchronous timing device output and the correct time of each earthquake source contact of record just needed to stablize between a kind of and true time.In addition, the systematic error of timing device also is a key factor of influence final earthquake source contact time output.
The utility model content
The purpose of this utility model is to provide a kind of " multichannel submarine seismograph timer " of measuring multichannel earthquake trigger pip, for marine geologic survey submarine seismograph (OBS) provides the precise time metering, overcome OBS internal clocking blind spot, make the segmentation of OBS geological data continuously, accurately, in marine geologic survey, obtain meticulous reliable, clear true seabed formation imaging and characteristic attribute thereof.Improve the detection accuracy and the work efficiency of submarine earthquake exploration.
The utility model multichannel submarine seismograph timer, be used for output near high-precision 1pps pulse signal and timing measuring data between true time, converging the back with the arrangement of submarine seismograph digital data recording system provides the most basic original time data for submarine seismograph obtains topographic profile, comprises the jamming-proof shielding case of electrostatic prevention and is located at the interior circuit of shielding case.Described circuit comprises the MCU data processing unit, and the Switching Power Supply that is electrically connected with it and mu balanced circuit, GPS time service module, 1pps impulse output circuit, timing measuring data output circuit, dial, external signal input and stabilizing circuit.Described Switching Power Supply and mu balanced circuit are used to export the voltage stabilizing low-voltage dc power supply.Described GPS time service module comprises built-in GPS receiving element, is used to export 1pps pulse signal and timing measuring signal to the MCU data processing unit.Described MCU data processing unit, system is by the embedded system that comprises that arm processor and the steady temperature compensating crystal oscillator of connected height are formed, the data-signal that is used for the logical process link block adopts the 1pps pulse signal calibration of GPS time service module output, the systematic error of elimination crystal oscillator timing.Described 1pps impulse output circuit is used to export the 1pps pulse signal through the correction of MCU data processing unit.Described timing measuring data output circuit is used to export the timing measuring data-signal through MCU data processing unit calculation process.Described dial is connected with the IO of MCU data processing unit end, is used to be provided with the initial big gun number of measurement starting point.
Consider that built-in GPS receiving element fault can not receive the possibility of gps signal, described GPS time service module also comprises outside 1pps pulse signal place in circuit, external GPS signal place in circuit, and switch selection by switch between the described built-in GPS receiving element, be used to import outside 1pps pulse signal and timing measuring signal to the MCU data processing unit.Therefore when built-in GPS receiving element fault, can be connected information such as acquisition gps time, position, satellite number with external GPS.
For the work that ensures multichannel submarine seismograph timer is not subjected to the external environment condition electromagnetic interference (EMI) and influences, the signal incoming end of described outside 1pps pulse signal place in circuit is provided with high-speed photoelectric coupler; The signal output part of described 1pps impulse output circuit is provided with high-speed photoelectric coupler; Described timing measuring data output circuit is a RS232 serial port output circuit.
For easy to operate, better realize man-machine interaction, the utility model multichannel submarine seismograph timer also is provided with LCD display circuit, warning LED and the hummer that is electrically connected with described MCU data processing unit.Described LCD display circuit is connected with the IO end of MCU data processing unit, is used for demonstration time, longitude and latitude, reaches number of satellite information.Described warning LED and hummer are used for fault alarm.
The utility model multichannel submarine seismograph timer is inner uses high steady temperature compensating crystal oscillator timing, and is provided with GPS time service module.In the time that gps satellite signal can't be received, realize inner high-precision timing by the steady temperature compensating crystal oscillator of height; When receiving gps satellite signal, starting point between GPS time service module initialization true time, the high steady temperature compensating crystal oscillator timing signal of continuous 1pps pulse signal correction.This timer is each input signal output precise time data, guarantees the accuracy of submarine seismograph record data and the reliability of analysis data.The signal input of the utility model timer, output terminal are equipped with high-speed photoelectric coupler, and circuit is located in the jamming-proof shielding case of electrostatic prevention, can guarantee that the work of this timer is not subjected to extraneous disturbing effect.
The experiment proved that the utility model timer is owing to adopt stabilidyne, technical grade integrated electronic chip that reliability is high and the anti-tampering shielding case of electrostatic prevention, the work chip all adopts High Speed ICs.Therefore, timing is accurate, stable performance, and the adaptive temperature field width, non-fault stable operation is more than 2 months continuously; By the accurate time service of time service type GPS, high steady temperature compensating crystal oscillator timing per second can be measured multichannel simultaneously to clock, and in the triggered time in unlike signal source (UTC time), time precision can reach 0.00001 second.Can be widely used in the OBS relevant marine geophysics and science survey item, become the indispensable equipment of carrying out this type of research and production project.
Simultaneously, the utility model timer also possesses automatic tally function (dial), can be strict corresponding with navigational system survey line big gun number, realized the synchronous of OBS data collection in the marine geologic survey activity and alternate manner seismic data acquisition.
Description of drawings
Fig. 1 is the schematic block circuit diagram of the utility model timer;
Fig. 2 is GPS time service module and the built-in GPS receiving element circuit of the utility model timer;
Fig. 3 is the outside 1pps pulse signal place in circuit of the GPS time service module of the utility model timer;
Fig. 4 is the external GPS signal place in circuit of the GPS time service module of the utility model timer;
Fig. 5 is the timing measuring data output circuit of the utility model timer.
Among the above figure: R is a resistance, and C is an electric capacity, and Q is a triode, and VCC is an operating voltage, and D is a diode; L is a telefault.
Embodiment
Below in conjunction with accompanying drawing and preferred embodiment technical solutions of the utility model are further specified:
Be illustrated in figure 1 as the schematic block circuit diagram of the utility model timer, circuit comprises the MCU data processing unit, and the Switching Power Supply and mu balanced circuit, GPS time service module, 1pps impulse output circuit, timing measuring data output circuit, dial, LCD display circuit, warning LED and the hummer that are electrically connected with it.Described Switching Power Supply and mu balanced circuit are used to export the operating voltage of voltage stabilizing low-voltage dc power supply as timer.Described GPS time service module adopts U-BLOX high precision time service type GPS receiver, is used to export 1pps pulse signal and timing measuring signal to the MCU data processing unit; Also comprise outside 1pps pulse signal place in circuit, external GPS signal place in circuit, and switch selection by switch between the described built-in GPS receiving element, be used to import outside 1pps pulse signal and timing measuring signal to the MCU data processing unit.Therefore when built-in GPS receiving element fault, can be connected information such as acquisition gps time, position, satellite number with external GPS.Described MCU data processing unit, system is by comprising that (with kernel is that 32 LPC2138 chips are as the host CPU deal with data to arm processor, stable speed is fast) and be connected in the embedded system that the high steady temperature compensating crystal oscillator (the high steady temperature compensating crystal oscillator of TCXO) of arm processor XTAL end is formed, the data that are used for the logical process link block adopt the 1pps pulse signal calibration of GPS time service module output, the systematic error of elimination crystal oscillator timing.Described 1pps impulse output circuit is provided with high-speed photoelectric coupler at pulse signal output end, is used to export the 1pps pulse signal through the correction of MCU data processing unit.Described timing measuring data output circuit is used to export the timing measuring signal through the correction of MCU data processing unit.Described LCD display circuit is connected with the IO end of MCU data processing unit, is used for demonstration time, longitude and latitude, reaches number of satellite information.Described dial is connected with the IO of MCU data processing unit end, is used to be provided with big gun number.Described warning LED and hummer are used for fault alarm.
Fig. 2 is the built-in GPS time service circuit of the GPS time service module of the utility model timer.P6 is the terminal that is connected with gps antenna; P7 is the lead-out terminal of the 1pps pulse signal 1pps_LEA of built-in GPS receiving element output; U6 is a LEA-4T GPS receiver module chip, and 3 pin and 4 pin are exported timing measuring signal RXD_LEA and timing measuring signal TXD_LEA respectively; JRST is a GPS receiver module chip reset button; U23 is high-speed cmos phase inverter 74HC04; U22 is a high-speed photoelectric coupler.
Fig. 3 is the outside 1pps pulse signal place in circuit of the GPS time service module of the utility model timer.P5 is that outside 1pps pulse signal inserts terminal; U25 is a high-speed photoelectric coupler; 1pps_LEA is the 1pps pulse signal of built-in GPS receiving element output; The 1pps pulse signal export the MCU data processing unit to, switch 1pps pulse signal or the outside 1pps pulse signal of selecting built-in GPS receiving element output by switch S P21.
Fig. 4 is the external GPS signal place in circuit of the GPS time service module of the utility model timer.COM end is the RS232 serial port, is used for docking with external GPS such as boat-carrying GPS; U5 is serial port level transferring chip MAX3232; External GPS signal TXD_GPS and external GPS signal RXD_GPS switch output by switch S P13.
Fig. 5 is the timing measuring data output circuit of the utility model timer.P0.9_RXD1 and P0.8_TXD1 are for handling the timing measuring signal of back output among the figure through the MCU data processing unit, and the timing measuring signal that is switched different passages by switch S P1 is exported from RS232 serial port COM2.U3 and U4 are serial port level transferring chip MAX3232.
After the GPS time service module of the utility model timer received four or above satellite-signal, output high precision time signal was to the MCU data processing unit.The MCU data processing unit is by the high temperature compensating crystal oscillator timing of high-precision TCXO, and the accurate 1pps pulse signal that utilizes the output of GPS time service module is to after the time signal correction and handling, by 1pps impulse output circuit output 1pps pulse signal and by R timing measuring data output circuit output timing measuring signal.Simultaneously, the MCU data processing unit exports related data to demonstration time on the LCD display circuit, longitude and latitude, number of satellite and initial big gun number (manually setting by dial).
Timing measuring: U-BLOX high precision time service type GPS receiver is by the back locking more than 4 of exterior antenna equipment locking transit satellite, output 1pps pulse signal; The high steady temperature compensating crystal oscillator time synchronisation of UTCXO.When crystal oscillator cycle second and adjacent homophase 1pps pulse interval cycle synchronisation error during less than 1 μ s, timing measuring entering signal stably measured state.
In case when built-in GPS receiving element breaks down, the MCU data processing unit will detect immediately, and by the IO signal LED be extinguished, the Signal Fail time promptly drove hummer above 20 seconds and sends prompt tone, recovered normal up to signal.
The utility model timer adopts the time service of U-BLOX high precision time service type GPS receiver, adopts the high steady temperature compensating crystal oscillator timing of TCXO, utilizes the 1pps pulse signal calibration of GPS time service module output simultaneously, to eliminate the cumulative errors that the crystal oscillator timing is produced; The MCU data processing unit selects for use the embedded scheme of ARM to handle, and adopting kernel is that 32 LPC2138 chips are the host CPU deal with data, and travelling speed is fast; By software algorithm, the 1pps pulse signal to be handled, the influence that not brought by the 1pps pulse stochastic error of GPS can provide more reliable, stable timing measuring.Through experimental verification, the Specifeca tion speeification of the utility model timer is:
The initial timing accuracy of 1pps pulse signal: ± 50ns;
The 1pps pulse signal keeps precision: ± 10 μ s (after 24 hours);
ARM response speed: 0.9*60=54MIPS;
Individual instructions execution speed: 0.018 μ s; Computed in software postpones: about 0.3 μ s.
Claims (8)
1. multichannel submarine seismograph timer, be used for output near high-precision 1pps pulse signal and timing measuring data between true time, converge the back with the arrangement of submarine seismograph digital data recording system and provide the original time data for submarine seismograph obtains topographic profile, comprise the jamming-proof shielding case of electrostatic prevention and be located at the interior circuit of shielding case, it is characterized in that: described circuit comprises the MCU data processing unit, and the Switching Power Supply and the mu balanced circuit that are electrically connected with it, GPS time service module, the 1pps impulse output circuit, the timing measuring data output circuit, dial, external signal input and stabilizing circuit;
Described Switching Power Supply and mu balanced circuit are used to export the voltage stabilizing low-voltage dc power supply;
Described GPS time service module comprises built-in GPS receiving element, is used to export 1pps pulse signal and timing measuring signal to the MCU data processing unit;
Described MCU data processing unit, the data-signal that is used for the logical process link block, adopting the 1pps pulse signal calibration of GPS time service module output, the systematic error of elimination crystal oscillator timing, is by the embedded system that comprises that arm processor and the steady temperature compensating crystal oscillator of connected height are formed;
Described 1pps impulse output circuit is used to export the 1pps pulse signal through the correction of MCU data processing unit;
Described timing measuring data output circuit is used to export the timing measuring signal through the correction of MCU data processing unit;
Described dial is connected with the IO of MCU data processing unit end, is used to be provided with the initial big gun number of measurement starting point.
2. multichannel submarine seismograph timer as claimed in claim 1, it is characterized in that: described GPS time service module also comprises outside 1pps pulse signal place in circuit, external GPS signal place in circuit, and switch selection by switch between the described built-in GPS receiving element, be used to import outside 1pps pulse signal and timing measuring signal to the MCU data processing unit.
3. multichannel submarine seismograph timer as claimed in claim 2 is characterized in that: the signal incoming end of described outside 1pps pulse signal place in circuit is provided with high-speed photoelectric coupler, is used to prevent that described outside 1pps pulse signal from disturbing.
4. multichannel submarine seismograph timer as claimed in claim 1 is characterized in that: described timing measuring data output circuit is a RS232 serial port output circuit.
5. multichannel submarine seismograph timer as claimed in claim 1 is characterized in that: described arm processor is 32 LPC2138 chips.
6. multichannel submarine seismograph timer as claimed in claim 1 is characterized in that: the steady temperature compensating crystal oscillator of described height is the high steady temperature compensating crystal oscillator of TCXO.
7. multichannel submarine seismograph timer as claimed in claim 1, it is characterized in that: the signal output part of described 1pps impulse output circuit is provided with high-speed photoelectric coupler, is used to prevent that described external unit from disturbing.
8. " multichannel submarine seismograph timer " as claimed in claim 1 is characterized in that: described circuit also comprises LCD display circuit, warning LED and the hummer that is electrically connected with described MCU data processing unit;
Described LCD display circuit is connected with the IO end of MCU data processing unit, is used for demonstration time, longitude and latitude, reaches number of satellite information;
Described warning LED and hummer are used for fault alarm.
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| CN 201020272264 CN201681269U (en) | 2010-07-27 | 2010-07-27 | Multi-path submarine seismograph precision timer |
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| CN 201020272264 CN201681269U (en) | 2010-07-27 | 2010-07-27 | Multi-path submarine seismograph precision timer |
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| CN201681269U true CN201681269U (en) | 2010-12-22 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103838135A (en) * | 2014-02-24 | 2014-06-04 | 国家海洋局第一海洋研究所 | Pulse signal precise timing device based on GPS module |
| CN104076400A (en) * | 2014-05-08 | 2014-10-01 | 珠海市泰德企业有限公司 | Time service device and time service method for data collecting in earthquake deep well monitoring |
| CN104903747A (en) * | 2012-08-16 | 2015-09-09 | 马格塞斯公司 | Ocean bottom seismic node system |
| CN106909065A (en) * | 2017-04-19 | 2017-06-30 | 中国科学院地质与地球物理研究所 | A kind of real-time clock clock correction bearing calibration of prospecting instrument |
| CN108008465A (en) * | 2017-10-25 | 2018-05-08 | 武汉市工程科学技术研究院 | Signal source triggered time acquisition methods in engineering geophysics signal acquisition |
| CN110262210A (en) * | 2019-06-28 | 2019-09-20 | 北斗天汇（北京）科技有限公司 | Crystal oscillator based on counter is kept time method |
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2010
- 2010-07-27 CN CN 201020272264 patent/CN201681269U/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104903747A (en) * | 2012-08-16 | 2015-09-09 | 马格塞斯公司 | Ocean bottom seismic node system |
| CN103838135A (en) * | 2014-02-24 | 2014-06-04 | 国家海洋局第一海洋研究所 | Pulse signal precise timing device based on GPS module |
| CN104076400A (en) * | 2014-05-08 | 2014-10-01 | 珠海市泰德企业有限公司 | Time service device and time service method for data collecting in earthquake deep well monitoring |
| CN106909065A (en) * | 2017-04-19 | 2017-06-30 | 中国科学院地质与地球物理研究所 | A kind of real-time clock clock correction bearing calibration of prospecting instrument |
| CN106909065B (en) * | 2017-04-19 | 2019-07-19 | 中国科学院地质与地球物理研究所 | A kind of real-time clock clock deviation bearing calibration of prospecting instrument |
| CN108008465A (en) * | 2017-10-25 | 2018-05-08 | 武汉市工程科学技术研究院 | Signal source triggered time acquisition methods in engineering geophysics signal acquisition |
| CN108008465B (en) * | 2017-10-25 | 2019-06-14 | 武汉市工程科学技术研究院 | Signal source triggered time acquisition methods in engineering geophysics signal acquisition |
| CN110262210A (en) * | 2019-06-28 | 2019-09-20 | 北斗天汇（北京）科技有限公司 | Crystal oscillator based on counter is kept time method |
| CN110262210B (en) * | 2019-06-28 | 2021-03-26 | 北斗天汇（北京）科技有限公司 | Crystal oscillator time keeping method based on counter |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20101222 Termination date: 20150727 |
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| EXPY | Termination of patent right or utility model |