CN114650082B - Data transmission system and method of logging instrument - Google Patents
Data transmission system and method of logging instrument Download PDFInfo
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- CN114650082B CN114650082B CN202210228977.3A CN202210228977A CN114650082B CN 114650082 B CN114650082 B CN 114650082B CN 202210228977 A CN202210228977 A CN 202210228977A CN 114650082 B CN114650082 B CN 114650082B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
- H04B3/546—Combination of signalling, telemetering, protection
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/14—Two-way operation using the same type of signal, i.e. duplex
- H04L5/1469—Two-way operation using the same type of signal, i.e. duplex using time-sharing
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L5/00—Arrangements affording multiple use of the transmission path
- H04L5/14—Two-way operation using the same type of signal, i.e. duplex
- H04L5/16—Half-duplex systems; Simplex/duplex switching; Transmission of break signals non-automatically inverting the direction of transmission
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Abstract
The application discloses a data transmission system and a data transmission method of a logging instrument. According to the technical scheme provided by the application, the data transmission system comprises a ground data transmission subsystem and a downhole data transmission subsystem which are connected through cables; the uplink data transmission and the downlink data transmission of the data transmission system adopt a time division multiplexing mode, and every T is adopted UP The underground modem module starts a downlink data transmission channel of the underground part, and the ground modem module starts the downlink data transmission channel of the ground part; at T DOWN And the underground modem module closes the downlink data transmission channel of the underground part, and the ground modem module opens the uplink data transmission channel of the ground part. By distinguishing between the uplink and downlink transmission periods, the impact of interference on the accuracy and time of signal transmission is reduced.
Description
Technical Field
The application relates to the field of logging data transmission, in particular to a data transmission system and method of logging instruments.
Background
In the petroleum drilling process, the underground condition needs to be detected, logging is performed by using a logging instrument, underground data is collected and then transmitted to the ground through a data transmission system, and main control software positioned on the ground is used for analysis, storage, display and the like. Meanwhile, various commands sent by the main control software are received by the underground logging instrument in the operation process to perform corresponding operations.
In the prior art, a continuous communication system is adopted for data transmission, and the continuous communication system comprises a channel training stage and a data transmission stage. Because the high power logging tool is continuously turned on and off during operation, the motor of the downhole tool may cause severe changes in the communication channel, causing the communication to reenter the training phase. In the communication system in the prior art, the anti-interference capability is weak, and only the slow change of a channel can be adapted, under the condition, the communication can be frequently interrupted and enters a training phase, and the training phase has long time, so that the data cannot be normally transmitted.
Disclosure of Invention
The present application has been made in view of the above problems, and it is an object of the present application to provide a data transmission system and method for a logging instrument that overcomes or at least partially solves the above problems.
According to the present application there is provided a data transmission system for a logging instrument, comprising: a surface data transmission subsystem and a downhole data transmission subsystem connected by a cable,
wherein, ground data transmission subsystem includes: the system comprises a ground modem module, a ground channel switching module, a ground uplink filter module and a ground cable coupling module;
the downhole data transmission subsystem comprises: the system comprises an underground modem module, an underground channel switching module, an underground downlink filter module and an underground cable coupling module;
the uplink data transmission and the downlink data transmission of the data transmission system adopt a time division multiplexing mode, and every T is adopted UP The underground modem module sends a control signal to the underground channel switching module to open the underground part of the downlink data transmission channel according to the downlink data transmission channel opening command, and the ground modem module sends a control signal to the ground channel switching module to open the ground part of the downlink data transmission channel and gate the ground part of the downlink data transmission channelAn uplink data transmission channel passing through the ground uplink filter module; at T DOWN The underground modem module sends a control signal to the underground channel switching module to close the underground part of the downlink data transmission channel, and the ground modem module sends a control signal to the ground channel switching module to close the ground part of the downlink data transmission channel and gate the uplink data transmission channel which does not pass through the ground uplink filter module.
In the above scheme, at T UP In the period, the underground modem module receives uplink data acquired by underground instruments, codes and modulates the uplink data and uplink pilot frequency data, and then transmits the uplink data and the uplink pilot frequency data to the underground cable coupling module, and then transmits the uplink data and the uplink pilot frequency data to the ground cable coupling module through a cable; after the ground cable coupling module receives the uplink data and the uplink pilot data, the ground channel switching module transmits the uplink data and the uplink pilot data to the ground modem module, and the ground modem module demodulates and decodes the uplink data and the uplink pilot data and transmits the uplink data and the uplink pilot data to a ground host;
wherein the frequency range of the uplink data is [ f USL ，f USH ]The frequency range of the uplink pilot data is [ f UPL ，f UPH ]，f UPL Greater than f USH 。
In the above scheme, in the downlink data transmission period, the ground modem module receives downlink data sent by the ground host, and after the downlink data is coded and modulated, the downlink data is transmitted to the ground cable coupling module through the ground channel switching module; the underground cable coupling module receives downlink data sent by the ground cable coupling module and uplink pilot frequency data obtained by coupling, the downlink data are transmitted to the underground downlink filter module through the underground channel switching module, the underground downlink filter module filters the uplink pilot frequency data, the downlink data obtained by filtering are transmitted to the underground modem module, and the underground modem module demodulates and decodes the downlink data and then transmits the downlink data to an underground instrument;
the underground modem module carries out code modulation on uplink pilot frequency data and then transmits the uplink pilot frequency data to the underground cable coupling module; the ground cable coupling module receives uplink pilot data sent by the underground cable coupling module and downlink data obtained by coupling, the uplink pilot data and the downlink data are transmitted to the ground uplink filter module, and after the downlink data are filtered by the ground uplink filter module, the uplink pilot data obtained by filtering are transmitted to the ground modem module through the ground channel switching module;
wherein the frequency range of the downlink data is [ f DSL ，f DSH ]，f DSL Greater than or equal to f USL ，f DSH Less than or equal to f USH 。
In the above scheme, the ground data transmission subsystem further includes:
the ground network interface control module is connected with the ground modem module;
in the downlink data transmission channel, a ground downlink digital-to-analog converter and a ground downlink filter module which are connected between the ground modem module and the ground channel switching module; the ground downlink power amplification module is connected between the ground channel switching module and the ground cable coupling module;
in the uplink data transmission channel, a ground uplink automatic gain control module and a ground uplink analog-to-digital converter are connected between the ground channel switching module and the ground modem module.
In the above scheme, the downhole data transmission subsystem further comprises:
the downhole instrument bus control module is connected with the downhole modem module;
in the uplink data transmission channel, a downhole digital-to-analog converter, a downhole uplink filter module and a downhole uplink power amplification module are connected between the downhole modem module and the downhole cable coupling module;
and in the downlink data transmission channel, a downlink automatic gain control module and a downlink analog-to-digital converter are connected between the downlink filter module and the downlink modem module.
In the above scheme, the uplink data transmission channel adopts an OFDM modulation scheme, and the downlink data transmission channel adopts a DBPSK modulation scheme.
In the scheme, the underground channel switching module is realized by adopting a 2-choice-1 multiplexer; the ground channel switching module is realized by two 2-to-1 multiplexers.
In the above scheme, the downhole downlink filter module is a band-pass filter, and the ground uplink filter module is a high-pass filter.
In the above scheme, the T UP Greater than said T DOWN The T is UP Greater than or equal to 200 milliseconds, said T DOWN Greater than or equal to 10 milliseconds.
According to another aspect of the present application, there is provided a data transmission method of a logging instrument implemented by using the data transmission system of a logging instrument described in the above scheme, the method including:
an uplink data transmission step, wherein the underground data transmission subsystem receives uplink data acquired by an underground instrument, the uplink data and uplink pilot frequency data are transmitted to the ground data transmission subsystem through a cable, and the ground data transmission subsystem transmits the uplink data and the uplink pilot frequency data to a ground host;
and a downlink data transmission step, wherein the ground data transmission subsystem receives downlink data transmitted by the ground host, transmits the downlink data and uplink pilot data obtained by coupling to the underground data transmission subsystem through a cable, and transmits downlink data obtained by filtering the uplink pilot data to the underground instrument through the underground data transmission subsystem.
According to the technical scheme provided by the application, the data transmission system comprises a ground data transmission subsystem and a downhole data transmission subsystem which are connected through cables; the uplink data transmission and the downlink data transmission of the data transmission system adopt a time division multiplexing mode, and every T is adopted UP The downhole modem module starts the downlink of the downhole part in a time periodThe ground modem module opens a downlink data transmission channel of the ground part; at T DOWN And the underground modem module closes the downlink data transmission channel of the underground part, and the ground modem module opens the uplink data transmission channel of the ground part. According to the technical scheme provided by the application, the influence of interference on the precision and time of signal transmission is reduced by distinguishing the uplink and downlink transmission time periods, so that the problems that in the prior art, when a communication channel is changed severely due to the fact that a logging instrument motor is continuously opened and closed, a system cannot track the change of the channel, and the error rate is increased, the synchronization is out of lock until normal communication is impossible, and a training stage is required to be reentered are solved.
The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.
Drawings
Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:
FIG. 1 shows a schematic diagram of a data transmission system of a logging instrument according to one embodiment of the application;
fig. 2 is a schematic diagram showing uplink data transmission and downlink data transmission duration and a switching manner according to an embodiment of the present application;
FIG. 3 illustrates a schematic diagram of spectral usage of a data transmission system of a logging instrument according to one embodiment of the present application;
FIG. 4 shows a schematic diagram of a data transmission system of a logging instrument according to another embodiment of the application;
fig. 5 is a schematic diagram of an uplink data transmission frame structure according to another embodiment of the present application;
FIG. 6 is a schematic diagram of signal spectrum during downlink data transmission of a downhole data transmission subsystem according to another embodiment of the application;
fig. 7 shows a schematic diagram of a signal spectrum of a terrestrial data transmission subsystem according to another embodiment of the present application;
FIG. 8 is a flow chart illustrating a method of data transmission of a logging instrument implemented using a data transmission system of a logging instrument according to another embodiment of the present application.
Detailed Description
Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
FIG. 1 shows a schematic diagram of a data transmission system of a logging instrument according to one embodiment of the application, as shown in FIG. 1, the data transmission system comprising: a surface data transmission subsystem 101 and a downhole data transmission subsystem 106; wherein, the liquid crystal display device comprises a liquid crystal display device,
the ground data transmission subsystem 101 includes: a terrestrial modem module 102, a terrestrial channel switching module 103, a terrestrial uplink filter module 104, and a terrestrial cable coupling module 105;
the downhole data transfer subsystem 106 includes: a downhole modem module 107, a downhole downstream filter module 108, a downhole channel switch module 109, and a downhole cable coupling module 110.
The uplink and downlink data transmission channels of the data transmission system are shown in fig. 1 with the directions of the arrows. The uplink data transmission refers to the transmission of data acquired by the downhole instrument to a ground host; the downlink data transmission refers to the surface host sending commands to the downhole tool. The downlink data transmission channel of the ground part comprises a ground modem module 102, a ground channel switching module 103 and a ground cable coupling module 105 which are connected in sequence; the downstream data transmission channels of the downhole part comprise a downhole cable coupling module 110, a downhole channel switching module 109, a downhole downstream filter module 108 and a downhole modem module 107, which are connected in sequence. The uplink data transmission channel of the underground part comprises an underground modem module 107 and an underground cable coupling module 110 which are connected in sequence; the uplink data transmission channel of the ground part comprises a ground cable coupling module 105, a ground uplink filter module 104, a ground channel switching module 103 and a ground modem module 102 which are connected in sequence.
The uplink data transmission and the downlink data transmission of the data transmission system adopt a time division multiplexing mode, and every T is adopted UP In the period, according to the downlink data transmission channel opening command, the downhole modem module 107 sends a control signal to the downhole channel switching module 109 to open the downlink data transmission channel of the downhole portion, and the ground modem module 102 sends a control signal to the ground channel switching module 103 to open the downlink data transmission channel of the ground portion and gate the uplink data transmission channel passing through the ground uplink filter module 104; at T DOWN The downhole modem module 107 sends a control signal to the downhole channel switching module 109 to close the downlink data transmission channel of the downhole portion, and the ground modem module 102 sends a control signal to the ground channel switching module 103 to close the downlink data transmission channel of the ground portion and gate the uplink data transmission channel that does not pass through the ground uplink filter module 104.
Specifically, fig. 2 is a schematic diagram illustrating uplink data transmission and downlink data transmission durations and a switching manner according to an embodiment of the present application. As shown in fig. 2, each transmission period of the uplink data has a length of T UP . The length of each transmission period of the downlink data depends on the command length of the transmitted downlink data, and the length of each transmission period of the downlink data in the system is greater than or equal to T DOWN In the downlink data transmission channelT of opening DOWN No downstream data (also called downstream command) is detected during the period of time, then after T has elapsed DOWN Closing a downlink data transmission channel of the underground part after the period of time; if T is opened in downlink data transmission channel DOWN The downlink command is detected by the downhole channel switching module 109 during the period, and the opening time of the downlink data transmission channel depends on the length of the downlink command sent, that is, the downlink data transmission channel of the downhole part is closed after the downlink data is received.
At T UP In the period, the underground modem module 107 receives the uplink data collected by the underground instrument, codes and modulates the uplink data and the uplink pilot data, and then transmits the uplink data and the uplink pilot data to the underground cable coupling module 110, and then transmits the uplink data and the uplink pilot data to the ground cable coupling module 105 through a cable; after receiving the uplink data and the uplink pilot data, the ground cable coupling module 105 transmits the uplink data and the uplink pilot data to the ground modem module 102 through the ground channel switching module 103, and the ground modem module 102 demodulates and decodes the uplink data and the uplink pilot data and transmits the decoded uplink data and the uplink pilot data to a ground host;
in the downlink data transmission period, the ground modem module 102 receives downlink data sent by the ground host, performs coded modulation on the downlink data, and transmits the downlink data to the ground cable coupling module 105 through the ground channel switching module 103; the downhole cable coupling module 110 receives downlink data sent by the ground cable coupling module 105 and uplink pilot data obtained by coupling, and transmits the downlink data to the downhole downlink filter module 108 through the downhole channel switching module 109, the downhole downlink filter module 108 filters the uplink pilot data, and then transmits downlink data obtained by filtering to the downhole modem module 107, and the downhole modem module 107 demodulates and decodes the downlink data and then transmits the downlink data to a downhole instrument;
the downhole modem module 107 performs code modulation on uplink pilot data and transmits the uplink pilot data to the downhole cable coupling module 110; the ground cable coupling module 105 receives the uplink pilot data sent by the downhole cable coupling module 110 and the downlink data obtained by coupling, and transmits the uplink pilot data and the downlink data to the ground uplink filter module 104, where the ground uplink filter module 104 filters the downlink data, and then transmits the uplink pilot data obtained by filtering to the ground modem module 102 through the ground channel switching module 103.
FIG. 3 illustrates a schematic of spectral usage of a data transmission system of a logging instrument according to one embodiment of the present application, as shown in FIG. 3, with the upstream and downstream data sharing signal bandwidth. The uplink data is burst uplink signal, and the frequency range is [ f ] USL ，f USH ]The method comprises the steps of carrying out a first treatment on the surface of the The downlink data is burst downlink signal, and the frequency range is [ f ] DSL ，f DSH ]The method comprises the steps of carrying out a first treatment on the surface of the The uplink pilot data is continuously transmitted by a downhole modem module of the downhole part, and the frequency range is [ f ] UPL ，f UPH ]. Wherein f UPL Greater than f USH ，f DSL Greater than or equal to f USL ，f DSH Less than or equal to f USH 。
Specifically, f USL The lowest frequency f of the bandwidth required for the uplink data transmission USH The highest frequency of the bandwidth required for the uplink data transmission; f (f) DSL The lowest frequency f of the bandwidth required for the downlink data transmission DSH The highest frequency of the bandwidth required for the downlink data transmission; f (f) UPL The lowest frequency f of the bandwidth required for the uplink pilot data transmission UPH And transmitting the highest frequency of the required bandwidth for the uplink pilot data.
According to the data transmission system of the logging instrument provided by the embodiment, the transmission time periods of uplink data transmission and downlink data transmission are mutually separated in a time division multiplexing mode, and a fixed T is arranged in the downlink transmission DOWN The time period is such that the downlink transmission occupies only a short T when no downlink data is detected DOWN And when downlink data transmission exists, the downlink data transmission is kept to be completed, the transmission of the downlink signals is ensured, and meanwhile, the time occupied by the downlink transmission is reduced as much as possible. A ground channel switching module is arranged,The underground channel switching module, the ground uplink filter module and the underground downlink filter module ensure the transmission rate and the anti-interference capability of data transmission. Meanwhile, when the downhole instrument works and the motor is continuously turned on and off, the uplink data transmission and the downlink data transmission are separated in a time division multiplexing mode, and the time duration of each uplink data transmission period and each downlink data transmission period is short, so that even if the situation that normal communication cannot be performed due to severe channel change occurs in the process of uploading data, after the uplink data transmission channel and the downlink data transmission channel are switched, normal signals are received when the uplink data transmission channel is accessed again, and the uplink data transmission can be continued after only a short time of training. The method solves the problems that in the prior art, when a continuous uplink data transmission mode is subjected to severe channel change, the channel change cannot be tracked, the error rate is increased, the synchronization is out of lock and the like until normal communication cannot be performed, and the communication reenters a long-time training stage, so that the data transmission rate is ensured, and the anti-interference capability of a data transmission system is also ensured.
Fig. 4 shows a schematic structural diagram of a data transmission system of a logging instrument according to another embodiment of the present application, as shown in fig. 4, the data transmission system includes: a surface data transmission subsystem 401 and a downhole data transmission subsystem 412;
wherein the ground data transmission subsystem 401 further comprises: a ground network interface control module 402, a ground modem module 403, a ground digital-to-analog converter 404, a ground downlink filter module 405, a ground channel switching module 406, a ground downlink power amplification module 407, a ground cable coupling module 408, a ground uplink filter module 409, a ground uplink automatic gain control module 410, and a ground uplink analog-to-digital converter 411;
the downhole data transfer subsystem 412 includes: a downhole instrument bus control module 413, a downhole modem module 414, a downhole digital-to-analog converter 415, a downhole upstream filter module 416, a downhole upstream power amplification module 417, a downhole cable coupling module 418, a downhole channel switching module 419, a downhole downstream filter module 420, a downhole downstream automatic gain control module 421, and a downhole analog-to-digital converter 422.
In the terrestrial portion, a terrestrial network interface control module 402 is connected to the terrestrial modem module 403; the surface network interface control module 402 is coupled to a surface host. In the downlink data transmission channel, a terrestrial downlink digital-to-analog converter 404 and a terrestrial downlink filter module 405 are further connected between the terrestrial modem module 403 and the terrestrial channel switching module 406; a ground downlink power amplification module 407 is further connected between the ground channel switching module 406 and the ground cable coupling module 408; in the uplink data transmission channel, between the terrestrial channel switching module 406 and the terrestrial modem module 403, a terrestrial uplink automatic gain control module 410 and a terrestrial uplink analog-to-digital converter 411 are also connected.
In a downhole portion, the downhole tool bus control module 413 is connected to the downhole modem module 414; the downhole tool bus control module 413 is coupled to the downhole tool. In the uplink data transmission channel, a downhole digital-to-analog converter 415, a downhole uplink filter module 416 and a downhole uplink power amplification module 417 are further connected between the downhole modem module 414 and the downhole cable coupling module 418; in the downstream data transmission channel, a downstream automatic gain control module 421 and a downstream analog-to-digital converter 422 are further connected between the downstream filter module 420 and the downstream modem module 414.
The ground host sends a downlink command to the ground network interface control module 402 through a network interface according to logging requirements, the ground network interface control module 402 analyzes the downlink command, carries out coding modulation through the ground modulation-demodulation module 403, and sequentially sends the downlink command to a cable through the ground cable coupling module 408 after passing through the ground downlink digital-to-analog converter 404, the ground downlink filter module 405, the ground channel switching module 406 and the ground downlink power amplification module 407, and sends the downlink command to the underground part through the cable; the downhole part is sequentially passed through the downhole cable coupling module 418, and then is sequentially passed through the downhole channel switching module 419, the downhole downlink filter module 420, the downhole automatic gain control module 421, the downhole analog-to-digital converter 422 and the downhole modem module 414, and then is transmitted to the downhole instrument by using the downhole instrument bus under the control of the downhole instrument bus control module 413.
The downhole instrument performs data acquisition according to the issued downlink command requirement, transmits acquired data to the downhole instrument bus control module 413 through the downhole instrument bus, transmits the acquired data to the downhole modem module 414 for coding modulation of uplink data, and sequentially transmits the data to the downhole digital-to-analog converter 415, the downhole uplink filter module 416 and the downhole uplink power amplification module 417, and transmits the uplink data to the ground part through the cable coupling module 418; after the ground part passes through the ground cable coupling module 408, the ground part sequentially enters the ground uplink filter module 409, the ground channel switching module 406, the ground uplink automatic gain control module 410, the ground uplink analog-to-digital converter 411 and the ground modem module 403, the original sampled data are demodulated and decoded in the ground modem module 403, and finally the data are sent to a ground host through a network interface of the ground network interface control module 402.
Preferably, in the data transmission system of the logging instrument, an OFDM modulation mode is adopted for an uplink data transmission channel, and a DBPSK modulation mode is adopted for a downlink data transmission channel. The uplink data transmission channel and the downlink data transmission channel adopt a burst half-duplex communication mode.
Fig. 5 is a schematic diagram of an uplink data transmission frame structure according to another embodiment of the present application. As shown in fig. 5, the uplink data transmission frame length of the burst is variable length, consisting of a fixed number of synchronization symbols, channel estimation symbols, channel analysis symbols, signaling symbols, and variable length data symbols. The synchronization symbol adopts a Linear Frequency Modulation (LFM) sequence, the duration is a complete OFDM symbol, and the synchronization symbol is used for OFDM symbol synchronization and automatic gain control of uplink data transmission; the channel estimation symbol uses two OFDM symbols, m sequences are used as modulation data, the modulation mode is fixed to BPSK, and the channel estimation symbol is mainly used for equalizer parameter training; the channel analysis symbol uses an OFDM symbol, uses m sequence as modulation data, adopts QPSK modulation mode, and is mainly used for estimating signal-to-noise ratio and carrying out bit allocation on each uplink sub-channel; the signaling symbol is used for carrying signaling data packet, transmitting the signaling data of the modem, and controlling the modulation and demodulation parameters, such as the length of the variable-length data symbol and the bit allocation table information of the uplink data transmission.
The silence frame refers to the uplink pilot data sent by the downhole modem module in the downhole portion, and the silence frame is continuously sent, i.e. the uplink pilot data is continuously sent.
Preferably, after the data transmission system of the logging instrument is powered on, an uplink data transmission channel is opened by default. The downhole modem module 414 of the downhole portion every T UP And in the period, sending a command for starting downlink data transmission to the ground modem module 403 of the ground part, and simultaneously starting a downlink data channel by the underground channel switching module 419 of the underground part, wherein the uplink data only sends a silence frame signal. The downhole modem module 414 of the downhole portion is at T DOWN And restarting uplink data transmission when downlink data is not detected or the downlink data is received in a period of time, and closing the downlink data by the underground channel switching module of the underground part. Wherein T is UP Greater than T DOWN Alternatively T UP Greater than or equal to 200 milliseconds, T DOWN Greater than or equal to 10 milliseconds.
Preferably, the downhole channel switching module 419 is implemented with a 2-to-1 multiplexer; the terrestrial channel switching module 406 is implemented using two 2-by-1 multiplexers, and the selection signals of the two multiplexers are opposite. The downhole modem module 414 of the downhole part controls the downhole channel switching module 419 of the downhole part to open or close the downstream data transmission channel of the downhole part; the ground modem module 403 of the ground portion controls the ground channel switching module 406 of the ground portion to open or close the downlink data transmission channel of the ground portion while gating whether the uplink data transmission channel passes through the ground uplink filter module.
Preferably, the downhole downlink filter module 420 is a bandpass filter for filtering uplink pilot data and low-frequency end noise, and bandpass filteringThe cut-off frequency of the low frequency end of the device is f DSL The cut-off frequency of the high-frequency end is f DSH The method comprises the steps of carrying out a first treatment on the surface of the The above-mentioned ground uplink filter module 409 is a high-pass filter, and is used for filtering to obtain uplink pilot data, and the cut-off frequency of the high-pass filter is f UPL 。
Fig. 6 is a schematic diagram of signal spectrum during downlink data transmission of a downhole data transmission subsystem according to another embodiment of the application. As shown in fig. 6, the downhole channel switching module is a 2-to-1 multiplexer, and the downhole modem module sends a control signal to the downhole channel switching module to open or close a downlink data transmission channel of a downhole portion, wherein the control signal is 0 to open the downlink data transmission channel, that is, the downhole channel switching module is a channel, so that a downlink command and an uplink pilot signal can be transmitted, and the control signal is 1 to close the downlink data transmission channel, that is, the downhole channel switching module is an open circuit, and the downlink data transmission channel is disconnected and only uplink data can be transmitted.
In the downlink data transmission period, the uplink data transmission channel has no uplink data (the spectrum represented by the dotted line in the figure has no data, and the spectrum represented by the solid line has data) except the uplink pilot data; downstream data exists in the downstream data transmission channel. Specifically, the underground cable coupling module receives downlink data sent by the ground cable coupling module and uplink pilot data obtained by coupling (the downlink data and the uplink pilot data are coupled together through the same cable), the downlink data are transmitted to the underground downlink filter module through the underground channel switching module, and the underground downlink filter module (band-pass filter) filters the uplink pilot data to obtain downlink data. In addition, the downhole downlink filter module can also filter noise at the low frequency end.
Fig. 7 shows a schematic diagram of a signal spectrum of a terrestrial data transmission subsystem according to another embodiment of the present application. As shown in fig. 7, the terrestrial channel switching module includes two 2-to-1 multiplexers, and the selection signals of the two 2-to-1 multiplexers are opposite. Specifically, the control ends of the two 2-option 1 multiplexers are connected with the ground modem module, the ground modem module controls the data transmission system to be in an uplink data transmission period or a downlink data transmission period by transmitting control signals to the control ends of the two 2-option 1 multiplexers, if the control signals are 0, the downlink data transmission channel is started, meanwhile, the uplink data transmission channel is gated through the ground uplink filter module, and the downlink data transmission channel can transmit downlink commands, but meanwhile, because the downlink commands are coupled to the cable, the downlink commands are required to be filtered by the ground uplink filter module, and only uplink pilot data is reserved to enter the ground modem module through the uplink data transmission channel of the ground uplink filter module; and if the control signal is 1, the downlink data transmission channel is closed, the downlink command is shielded, the downlink command is not coupled to the cable, meanwhile, the uplink data transmission channel which does not pass through the ground uplink filter module is gated, the uplink data transmission channel can transmit uplink data and uplink pilot signals, and the uplink data and the uplink pilot signals are not filtered by the ground uplink filter module.
Specifically, at T UP In the period, the ground modem module outputs a control signal of 1, closes a downlink data transmission channel, shields a downlink command, and after the ground cable coupling module receives uplink data and uplink pilot data, the ground cable coupling module gates the uplink data transmission channel which does not pass through the ground uplink filter module through the ground channel switching module, and the uplink data and the uplink pilot data are transmitted to the ground modem module without filtering;
in the downlink data transmission period, the ground modem module outputs a control signal of 0, opens a downlink data transmission channel, and gates an uplink data transmission channel passing through the ground uplink filter module. The ground modem module receives downlink data issued by the ground host, codes and modulates the downlink data, and then transmits the downlink data to the ground cable coupling module through a multiplexer in a downlink channel in the ground channel switching module; the ground cable coupling module receives uplink pilot data sent by the underground cable coupling module and downlink data obtained by coupling, the uplink pilot data and the downlink data are transmitted to the ground uplink filter module, and the ground uplink filter module (high-pass filter) only keeps the uplink pilot data to be transmitted to the ground modem module after filtering the downlink data.
FIG. 8 is a flow chart illustrating a method of data transmission of a logging instrument implemented using a data transmission system of a logging instrument according to another embodiment of the present application. As shown in fig. 8, the method includes the steps of:
step S801, uplink data transmission step, the underground data transmission subsystem receives the uplink data collected by the underground instrument, transmits the uplink data and the uplink pilot data to the ground data transmission subsystem through the cable, and transmits the uplink data and the uplink pilot data to the ground host through the ground data transmission subsystem.
Step S802, a downlink data transmission step, wherein the ground data transmission subsystem receives downlink data sent by a ground host, the downlink data and uplink pilot data obtained by coupling are transmitted to the underground data transmission subsystem through a cable, and the downlink data obtained by filtering the uplink pilot data is transmitted to an underground instrument through the underground data transmission subsystem.
In particular, the specific implementation process of the uplink data transmission step and the downlink data transmission step may be referred to the description of each embodiment above, and will not be repeated.
According to the data transmission method of the logging instrument using the data transmission system of the logging instrument provided in the embodiment, transmission periods of uplink data transmission and downlink data transmission are separated from each other in a time division multiplexing manner, and a fixed T is set in the downlink transmission DOWN The time period is such that the downlink transmission occupies only a short T when no downlink data is detected DOWN And when downlink data transmission exists, the downlink data transmission is kept to be completed, the transmission of the downlink signals is ensured, and meanwhile, the time occupied by the downlink transmission is reduced as much as possible. Meanwhile, when the downhole instrument works and the motor is continuously turned on and off, the uplink data transmission and the downlink data transmission are separated in a time division multiplexing mode, and the time duration of each uplink data transmission period and each downlink data transmission period is shorter, so that even if the situation that normal communication cannot be performed due to severe channel change in the process of uploading data occurs, the uplink data transmission channel and the downlink data transmission channel are passed throughAfter the channel is switched, the normal signal is received when the uplink data transmission channel is accessed again, and the uplink data transmission can be continued only after short training. The method solves the problems that in the prior art, when a continuous uplink data transmission mode is subjected to severe channel change, the channel change cannot be tracked, the error rate is increased, the synchronization is out of lock and the like until normal communication cannot be performed, and the communication reenters a long-time training stage, so that the data transmission rate is ensured, and the anti-interference capability of a data transmission system is also ensured.
In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the application may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.
Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the application, various features of the application are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, the disclosed method should not be construed as reflecting the intention that: i.e., the claimed application requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this application.
Those skilled in the art will appreciate that the modules in the apparatus of the embodiments may be adaptively changed and disposed in one or more apparatuses different from the embodiments. The modules or units or components of the embodiments may be combined into one module or unit or component and, furthermore, they may be divided into a plurality of sub-modules or sub-units or sub-components. Any combination of all features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or units of any method or apparatus so disclosed, may be used in combination, except insofar as at least some of such features and/or processes or units are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.
Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the application and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.
Various component embodiments of the application may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that some or all of the functions of some or all of the components in accordance with embodiments of the present application may be implemented in practice using a microprocessor or Digital Signal Processor (DSP). The present application can also be implemented as an apparatus or device program (e.g., a computer program and a computer program product) for performing a portion or all of the methods described herein. Such a program embodying the present application may be stored on a computer readable medium, or may have the form of one or more signals. Such signals may be downloaded from an internet website, provided on a carrier signal, or provided in any other form.
It should be noted that the above-mentioned embodiments illustrate rather than limit the application, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, third, etc. do not denote any order. These words may be interpreted as names.
Claims (10)
1. A data transmission system for a logging instrument, comprising: a surface data transmission subsystem and a downhole data transmission subsystem connected by a cable,
wherein, ground data transmission subsystem includes: the system comprises a ground modem module, a ground channel switching module, a ground uplink filter module and a ground cable coupling module;
the downhole data transmission subsystem comprises: the system comprises an underground modem module, an underground channel switching module, an underground downlink filter module and an underground cable coupling module;
the uplink data transmission and the downlink data transmission of the data transmission system adopt a time division multiplexing mode, and every T is adopted UP The underground modem module sends a control signal to the underground channel switching module to open the underground part of the downlink data transmission channel according to the downlink data transmission channel opening command, and the ground modem module sends a control signal to the ground channel switching module to open the ground part of the downlink data transmission channel and gate the uplink data transmission channel passing through the ground uplink filter module; at T DOWN The underground modem module sends a control signal to the underground channel switching module to close the underground part of the downlink data transmission channel, and the ground modem module sends a control signal to the ground channel switching module to close the ground part of the downlink data transmission channel and gate the uplink data transmission channel which does not pass through the ground uplink filter module.
2. The data transmission system of claim 1, wherein,
at T UP In the period, the underground modem module receives uplink data acquired by underground instruments, codes and modulates the uplink data and uplink pilot frequency data, and then transmits the uplink data and the uplink pilot frequency data to the underground cable coupling module, and then transmits the uplink data and the uplink pilot frequency data to the ground cable coupling module through a cable; after the ground cable coupling module receives the uplink data and the uplink pilot data, the ground channel switching module transmits the uplink data and the uplink pilot data to the ground modem module, and the ground modem module demodulates and decodes the uplink data and the uplink pilot data and transmits the uplink data and the uplink pilot data to a ground host;
wherein the frequency range of the uplink data is [ f USL ，f USH ]The frequency range of the uplink pilot data is [ f UPL ，f UPH ]，f UPL Greater than f USH 。
3. The data transmission system of claim 2, wherein,
in a downlink data transmission period, the ground modem module receives downlink data issued by a ground host, codes and modulates the downlink data, and transmits the downlink data to the ground cable coupling module through the ground channel switching module; the underground cable coupling module receives downlink data sent by the ground cable coupling module and uplink pilot frequency data obtained by coupling, the downlink data are transmitted to the underground downlink filter module through the underground channel switching module, the underground downlink filter module filters the uplink pilot frequency data, the downlink data obtained by filtering are transmitted to the underground modem module, and the underground modem module demodulates and decodes the downlink data and then transmits the downlink data to an underground instrument;
the underground modem module carries out code modulation on uplink pilot frequency data and then transmits the uplink pilot frequency data to the underground cable coupling module; the ground cable coupling module receives uplink pilot data sent by the underground cable coupling module and downlink data obtained by coupling, the uplink pilot data and the downlink data are transmitted to the ground uplink filter module, and after the downlink data are filtered by the ground uplink filter module, the uplink pilot data obtained by filtering are transmitted to the ground modem module through the ground channel switching module;
wherein the frequency range of the downlink data is [ f DSL ，f DSH ]，f DSL Greater than or equal to f USL ，f DSH Less than or equal to f USH 。
4. The data transmission system of claim 1, wherein the terrestrial data transmission subsystem further comprises:
the ground network interface control module is connected with the ground modem module;
in the downlink data transmission channel, a ground downlink digital-to-analog converter and a ground downlink filter module which are connected between the ground modem module and the ground channel switching module; the ground downlink power amplification module is connected between the ground channel switching module and the ground cable coupling module;
in the uplink data transmission channel, a ground uplink automatic gain control module and a ground uplink analog-to-digital converter are connected between the ground channel switching module and the ground modem module.
5. The data transmission system of claim 1, wherein the downhole data transmission subsystem further comprises:
the downhole instrument bus control module is connected with the downhole modem module;
in the uplink data transmission channel, a downhole digital-to-analog converter, a downhole uplink filter module and a downhole uplink power amplification module are connected between the downhole modem module and the downhole cable coupling module;
and in the downlink data transmission channel, a downlink automatic gain control module and a downlink analog-to-digital converter are connected between the downlink filter module and the downlink modem module.
6. A data transmission system according to claim 3, wherein the uplink data transmission channel adopts an OFDM modulation scheme, and the downlink data transmission channel adopts a DBPSK modulation scheme.
7. A data transmission system according to claim 1 or 3, wherein the downhole channel switching module is implemented using a 2-to-1 multiplexer; the ground channel switching module is realized by two 2-to-1 multiplexers.
8. A data transmission system according to claim 1 or 3, wherein the downhole downstream filter module is a band pass filter and the surface upstream filter module is a high pass filter.
9. The data transmission system of claim 1, wherein the T is UP Greater than said T DOWN The T is UP Greater than or equal to 200 milliseconds, said T DOWN Greater than or equal to 10 milliseconds.
10. A method of data transmission of a logging instrument implemented using a data transmission system of a logging instrument according to any one of claims 1-9, the method comprising:
an uplink data transmission step, wherein the underground data transmission subsystem receives uplink data acquired by an underground instrument, the uplink data and uplink pilot frequency data are transmitted to the ground data transmission subsystem through a cable, and the ground data transmission subsystem transmits the uplink data and the uplink pilot frequency data to a ground host;
and a downlink data transmission step, wherein the ground data transmission subsystem receives downlink data transmitted by the ground host, transmits the downlink data and uplink pilot data obtained by coupling to the underground data transmission subsystem through a cable, and transmits downlink data obtained by filtering the uplink pilot data to the underground instrument through the underground data transmission subsystem.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1985449A (en) * | 2004-07-14 | 2007-06-20 | Sk电信有限公社 | Method and system for generating switching timing signal for separating transmitting and receving signal in RF repeater of mobile telecommunication network using TDD and OFDM modulation |
| CN207867701U (en) * | 2018-02-07 | 2018-09-14 | 西安思坦仪器股份有限公司 | A kind of data rapid transmission system suitable for single-cord well logging cable |
| CN110984969A (en) * | 2019-12-21 | 2020-04-10 | 中国电波传播研究所（中国电子科技集团公司第二十二研究所） | Single-core cable transmission device with high reliability and self-adaptive rate adjustment and data transmission method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2907456C (en) * | 2013-03-28 | 2020-05-12 | Evolution Engineering Inc. | Electromagnetic communications system and method for a drilling operation |
| WO2017052514A1 (en) * | 2015-09-22 | 2017-03-30 | Halliburton Energy Services, Inc. | Scalable communication system for hydrocarbon wells |
| US10358915B2 (en) * | 2016-03-03 | 2019-07-23 | Halliburton Energy Services, Inc. | Single source full-duplex fiber optic telemetry |
-
2022
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1985449A (en) * | 2004-07-14 | 2007-06-20 | Sk电信有限公社 | Method and system for generating switching timing signal for separating transmitting and receving signal in RF repeater of mobile telecommunication network using TDD and OFDM modulation |
| CN207867701U (en) * | 2018-02-07 | 2018-09-14 | 西安思坦仪器股份有限公司 | A kind of data rapid transmission system suitable for single-cord well logging cable |
| CN110984969A (en) * | 2019-12-21 | 2020-04-10 | 中国电波传播研究所（中国电子科技集团公司第二十二研究所） | Single-core cable transmission device with high reliability and self-adaptive rate adjustment and data transmission method thereof |
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