WO2016107557A1 - 一种自适应有线通信方法和测井方法及装置 - Google Patents
一种自适应有线通信方法和测井方法及装置 Download PDFInfo
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- WO2016107557A1 WO2016107557A1 PCT/CN2015/099516 CN2015099516W WO2016107557A1 WO 2016107557 A1 WO2016107557 A1 WO 2016107557A1 CN 2015099516 W CN2015099516 W CN 2015099516W WO 2016107557 A1 WO2016107557 A1 WO 2016107557A1
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- 230000006854 communication Effects 0.000 title claims abstract description 186
- 238000004891 communication Methods 0.000 title claims abstract description 181
- 238000000034 method Methods 0.000 title claims abstract description 52
- 238000012549 training Methods 0.000 claims abstract description 50
- 238000011156 evaluation Methods 0.000 claims abstract description 24
- 230000003044 adaptive effect Effects 0.000 claims description 29
- 230000005540 biological transmission Effects 0.000 description 13
- 230000008859 change Effects 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 230000006978 adaptation Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK 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
Definitions
- the invention relates to the field of remote logging technology, and in particular to an adaptive wired communication method and a logging method and device.
- the signal inevitably has a bit error phenomenon in the transmission process, and the cause of the phenomenon includes the transmission line factor and the device environment factor. Since the application environment of the common communication system is relatively stable, it is usually tested before the normal communication, and then a series of communication parameters are adjusted according to the test result, and the use of the above communication parameters can be effectively used in the normal communication process to effectively overcome the error band. The problem that comes.
- the communication equipment is in a complex environment and requires real-time communication through long-distance cable lines. It is said that due to environmental impacts, such as the invisible communication cable between the well and the downhole, the temperature change in the underground environment is large, and the communication cable will be stretched at any time, it will have a great impact on the efficiency of data transmission, so ordinary The communication method is completely unable to meet the demand.
- Some of the existing dedicated logging systems are mostly improved in coding mode or modulation mode.
- communication interruption can only be solved by re-communication training after communication interruption, and such system pairs
- the requirements for communication cables are high and can only be applied to a particular type of cable.
- the document US 2010/0295702 A1 discloses a two-way pre-equalization system for high-speed remote transmission of downhole cable communication using OFDM (Orthogonal).
- OFDM Frequency Division Multiplexing
- the system does not improve the communication adaptability. It can be seen that such systems have poor stability and do not have dynamic adaptive functions.
- the technical problem to be solved by the present invention is to improve the stability of the communication system and to make it adaptable to suit various communication hardware and application environments.
- the present invention provides an adaptive wired communication method, including: S1: a first terminal sends communication data and training data to a second terminal according to a communication parameter; S2: the second terminal evaluates channel communication conditions according to the training data, and Adjusting, according to the evaluation result, a communication parameter used to send the communication data; S3: the second terminal sends the adjusted communication parameter to the first terminal to update the communication parameter.
- the method further includes repeatedly performing the steps S1 to S3.
- the method further includes: the second terminal acquiring a clock frequency of the first terminal; and the second terminal transmitting the adjusted communication parameter according to the clock frequency.
- the method further includes: the second terminal performs frame synchronization check.
- the first terminal sends the logging data and the training data to the second terminal by using a digital multi-carrier modulation method; the second terminal sends the Communication parameters.
- the communication parameter includes at least one of a frequency domain equalization parameter, a bit allocation parameter, and a channel coding parameter.
- step S2 when the communication parameter is a bit allocation parameter, adjusting, according to the evaluation result, the communication parameter used to transmit the communication data comprises: acquiring a signal to noise ratio of the channel; according to the signal to noise ratio The number of bits allocated to the audio is adjusted, the signal to noise ratio being proportional to the number of bits.
- adjusting communication parameters used for transmitting the communication data according to the evaluation result includes: acquiring a channel bandwidth and a sub-band bandwidth; acquiring a number of channels, the number of channels Is the ratio of the channel bandwidth to the sub-band bandwidth, and the number of channels is an integer power of two.
- the second terminal communicates with the first terminal in a time division multiplexing manner.
- the invention also provides a logging method, comprising: the adaptive wired communication method transmitting logging data, wherein the first terminal is a downhole end, and the second terminal is an uphole end.
- the present invention provides an adaptive wired communication system, including: a first terminal and a second terminal, wherein the first terminal is configured to send communication data and training data to the second terminal according to a communication parameter;
- the second terminal is configured to evaluate channel communication conditions according to the training data, and Adjusting, according to the evaluation result, a communication parameter used to send the communication data; and transmitting the adjusted communication parameter to the first terminal.
- the adaptive wired communication method and the logging method and device provided by the present invention evaluate the training data sent by the first terminal by using the second terminal, and adjust the communication parameters in real time according to the evaluation result, and then adjust the The subsequent communication parameters are sent to the first terminal, so that the first terminal can transmit data by using the real-time adjusted communication parameters, and the adaptive channel evaluation function is realized, which increases the stability of the communication system.
- FIG. 1 is a flowchart of an adaptive wired communication method according to a first embodiment of the present invention
- FIG. 2 is a schematic structural diagram of an adaptive wired communication system according to a third embodiment of the present invention.
- the adaptive wired communication method provided by the present invention is applicable to a wired communication system, especially for a scenario where the communication environment is relatively complicated, for example, the ambient temperature of the communication terminal often changes greatly, and the lines between the communication terminals are often stretched. .
- a first embodiment of the present invention provides an adaptive wired communication method, where the method includes:
- the first terminal sends the communication data and the training data to the second terminal according to the communication parameter.
- the communication data refers to data having practical meaning;
- the training sequence is a sequence known by the two ends of the communication before normal communication, and is used to enable the second terminal to determine the impact response characteristic of the channel, and the number of training data can be based on actual needs. The situation is set.
- the second terminal evaluates channel communication conditions according to the training data, and adjusts communication parameters used to send the communication data according to the evaluation result.
- the content of the evaluation may include content such as time domain equalization, frequency domain equalization, signal to noise ratio, and bit allocation of the channel, and the second terminal may determine an error of the communication data according to the original content of the training data and the actually received training data content, the error.
- the communication condition of the channel can be reflected, and then the second terminal can dynamically adjust the communication parameters according to the communication conditions of the channel to reduce the influence of channel conditions on the communication data.
- Various channels are known Evaluation methods, those skilled in the art should understand that existing channel estimation methods are feasible.
- S3 The second terminal sends the adjusted communication parameter to the first terminal to update the communication parameter.
- the first terminal may use the adjusted communication parameter to send data, and the communication rate may change according to the characteristics of the channel. If the channel condition becomes better, the communication rate will increase; otherwise, the communication rate will decrease. This achieves the goal of automatic adaptation to channel changes.
- step S2 if the evaluation result indicates that the current channel condition has not reached the preset minimum communication requirement, the normal communication state may be terminated, the debugging or communication training may be restarted, and the normal communication state is entered again after the training is completed.
- the second terminal evaluates the channel communication condition in the normal communication process, and adjusts the communication parameter in real time according to the evaluation result, and then sends the adjusted communication parameter to the first terminal, so that The first terminal can transmit data by using real-time adjusted communication parameters, and realizes the function of adaptive communication.
- the method in this embodiment further includes: repeatedly performing the steps S1 to S3. That is, the method can be executed cyclically, so that each time the first terminal sends the communication data and the training data, the adjusted communication parameters sent by the second terminal after the previous execution of the method are used, and the method can make the first terminal each time.
- the communication parameters used to transmit data are consistent with the current channel communication conditions, thereby increasing the stability of the communication system.
- the first terminal may transmit the log data and the training data to the second terminal using a digital multi-carrier modulation scheme.
- the communication parameter includes at least one of a frequency domain equalization parameter, a bit allocation parameter, and a channel coding parameter.
- step S2 when the communication parameter is a bit allocation parameter, adjusting the communication parameters used for transmitting the communication data according to the evaluation result includes:
- the second terminal acquires a signal to noise ratio of the channel
- the second terminal adjusts the number of bits allocated to the audio according to the signal to noise ratio, and the signal to noise ratio is proportional to the number of bits, that is, the higher the signal to noise ratio, the more bits allocated to the audio.
- adjusting the communication parameters used for transmitting the communication data according to the evaluation result includes:
- the second terminal acquires a channel bandwidth and a sub-band bandwidth
- the second terminal acquires the number of channels, the number of channels being a ratio of the channel bandwidth to the sub-band bandwidth, and the number of channels is an integer power of two.
- the frequency band of the channel is divided into a plurality of adjacent sub-bands, each of which is assigned a fixed frequency, and all of the fixed frequencies are integer multiples of the sub-band bandwidth (the range is 1 to 64 times).
- Each of the audio frequencies carries a certain amount of information, and the number of bits allocated to the audio (2 bits to 15 bits) depends on the signal to noise ratio of the audio band.
- the second terminal may send the communication parameter to the first terminal by using a phase modulation manner. Compared with the first terminal, the second terminal needs to send less data, and the environment is relatively stable.
- the second terminal in this embodiment uses phase modulation to transmit data, which is simple and reliable, and has high real-time performance.
- the method further includes:
- the second terminal acquires a clock frequency of the first terminal
- the second terminal transmits the adjusted communication parameter according to the clock frequency.
- the second terminal can determine the clock frequency of the information sending end (ie, the first terminal) by acquiring the phase information of the communication data. Because the environment in which the first terminal is located may be harsh, for example, the high temperature environment may affect the crystal frequency to change continuously, thereby affecting the rate of data running thereon, so the second terminal acquires the first terminal in real time during the communication process. Clock frequency. The second terminal then generates the clock frequency. For example, the digital frequency synthesizer can output the frequency to synchronize the clock frequency of the first terminal and the second terminal, thereby improving communication efficiency.
- the method further includes:
- the second terminal performs frame synchronization check.
- the first terminal and the second terminal may perform communication training first.
- the preferred solution belongs to a preferred communication training solution, that is, the second terminal may be based on the communication training process.
- the content of the training data sent by the first terminal determines a frame positioning sequence to ensure that in the normal communication process, the second terminal can accurately identify the starting position of each actual communication data and determine the criterion of the frame out of synchronization.
- the second terminal may determine whether the system is in an out-of-synchronization state according to the out-of-synchronization criterion, and if the step has been lost, the positioning sequence may be immediately captured, and accordingly, the first terminal Then, it is possible to retransmit only the erroneous frame without retransmitting all the communication data, thereby further improving the communication efficiency.
- the second terminal communicates with the first terminal in a time division multiplexing manner.
- the working mode of the adaptive wired communication method in this embodiment is a time division transmission mode, that is, the second terminal and the transmission signal switch of the first terminal are respectively opened in the allocated time, which is specifically the second terminal when the first terminal is opened.
- the second terminal When the second terminal is turned on, the first terminal is closed, and the second terminal sends data to the first terminal. This makes it possible for two communication terminals to transmit data to each other using a single physical channel.
- the second embodiment of the present invention further provides a logging method, which utilizes the above adaptive wired communication.
- the method sends log data, the first terminal is a downhole end, and the second terminal is an uphole end.
- the method includes three states: an initial state, a training state, and a normal state.
- the initialization state is first entered, and when the command to start training is received, the training state is entered; if the training is successful Then, it enters the normal state, and if the training fails, it returns to the initialization state; in the normal state, data communication can be performed, and if it is found through the channel evaluation that an abnormality cannot be communicated, the initialization state is returned.
- the training state includes: a process of establishing uplink and downlink communications, and determining communication parameters and uplink communication rates through training.
- the training of downlink communication is first performed, that is, the training of phase modulation (PSK) mode.
- PSK phase modulation
- the transmission signal switch of the well is turned on, the transmission signal switch of the well is closed, the fixed training sequence is sent by the ground, and the decoding is received by the underground.
- the received signal determines the decoding parameters.
- start uplink digital multi-carrier modulation (DMM-Digital Multicarrier) Modulation) training At this time, the signal switch on the well is turned off, and the down signal switch is turned on.
- the main contents of the training include AGC Training, TEQ Training, DDS Training, and frame.
- the system's working mode is switched to the time division transmission mode.
- the emission signal switches of the uphole and downhole are respectively opened in the allocated time.
- the well is closed, and the well is transmitted to the well.
- the well is closed, and the well sends a signal to the well.
- Part of the parameters are transmitted downhole through the Information Exchange. Then, you can enter normal mode and start normal data transmission.
- the normal mode includes: normal uplink and downlink data communication (up and down codec is determined by the training mode).
- the working mode is time-division transmission mode.
- the emission signal switches of the uphole and downhole are respectively opened in the allocated time. When the well is opened, the well is closed, and the well is transmitted to the well. When the well is opened, the well is closed, and the well sends a signal to the well.
- Downhole uplink coding includes, interleave, Reed Solomon coding (RS Encode), constellation coding (QAM Encode), inverse fast Fourier transform (IFFT), automatic gain (AGC); uplink decoding including, automatic gain (AGC) ), time domain equalization (TEQ), fast Fourier transform (FFT), frequency domain equalization (FEQ), clock synchronization (CLK Adjust), constellation decoding (QAM Decode), Reed Solomon decoding (RS Decode), data deinterleaving (Deinterleave).
- RS Encode Reed Solomon coding
- QAM Encode constellation coding
- IFFT inverse fast Fourier transform
- AGC automatic gain
- uplink decoding including, automatic gain (AGC) ), time domain equalization (TEQ), fast Fourier transform (FFT), frequency domain equalization (FEQ), clock synchronization (CLK Adjust), constellation decoding (QAM Decode), Reed Solomon decoding (RS Decode), data deinterleaving (Deinterleave).
- the communication cable used between the upper end of the well and the lower end of the well may be a seven-core logging cable, a single-core logging cable, a three-core logging cable, etc., different cable frequencies. Response, channel bandwidth, and signal-to-noise ratio are different.
- Single-channel uplink data rate when using seven-core logging cable can exceed 1000KBPS, downlink data rate exceeds 25KBPS; uplink data rate when using single-core logging cable exceeds 300KBPS, single-channel uplink data rate when using three-core logging cable More than 800KBPS, the specific data rate depends on the frequency response of the cable, the signal-to-noise ratio of the channel, and the number of channels.
- the method can automatically adapt according to the physical characteristics of different cables and the communication environment, so that the logging efficiency is higher and the adaptation range is wider.
- a third embodiment of the present invention provides an adaptive wired communication system. As shown in FIG. 2, the system includes: a first terminal and a second terminal, where
- the first terminal is configured to send communication data and training data to the second terminal according to the communication parameter;
- the second terminal is configured to evaluate channel communication conditions according to the training data, and adjust a communication parameter used to send the communication data according to the evaluation result; and send the adjusted communication parameter to the first terminal.
- the second terminal evaluates the channel communication condition in the normal communication process, and adjusts the communication parameter in real time according to the evaluation result, and then sends the adjusted communication parameter to the first terminal, so that The first terminal can transmit data by using real-time adjusted communication parameters, and realizes the function of adaptive communication.
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Abstract
Description
Claims (10)
- 一种自适应有线通信方法,其特征在于,包括:S1:第一终端根据通信参数向第二终端发送通信数据和训练数据;S2:第二终端根据所述训练数据对信道通信条件进行评估,并根据评估结果调整发送所述通信数据所采用的通信参数;S3:所述第二终端将调整后的通信参数发送至第一终端以对所述通信参数进行更新。
- 根据权利要求1所述的自适应有线通信方法,其特征在于,所述方法还包括:重复执行所述步骤S1至S3。
- 根据权利要求1或2所述的自适应有线通信方法,其特征在于,在所述步骤S3之前还包括:所述第二终端获取第一终端的时钟频率;所述第二终端按照所述时钟频率发送所述调整后的通信参数。
- 根据权利要求1或2所述的自适应有线通信方法,其特征在于,在所述步骤S1之前还包括:所述第二终端进行帧同步校核。
- 根据权利要求1或2所述的自适应有线通信方法,其特征在于,所述第一终端使用数字多载波调制方式向所述第二终端发送所述测井数据和所述训练数据;所述第二终端使用相位调制方式向所述第一终端发送所述通信参数。
- 根据权利要求5所述的自适应有线通信方法,其特征在于,所述通信参数包括频域均衡参数、比特分配参数、信道编码参数中的至少一个。
- 根据权利要求6所述的自适应有线通信方法,其特征在于,在所述步骤S2中,当所述通信参数是比特分配参数时,根据评估结果调整发送所述通信数据所采用的通信参数包括:获取信道的信噪比;根据所述信噪比调整分配到音频的比特数,所述信噪比与所述比特数成正比;或者在所述步骤S2中,当所述通信参数是信道编码参数时,根据评估结果调整发送所述通信数据所采用的通信参数包括:获取信道带宽和子频带带宽;获取信道数目,所述信道数目是所述信道带宽与所述子频带带宽的比值,并且所述信道数目是2的整数次方。
- 根据权利要求1或2所述的自适应有线通信方法,其特征在于,所述第二终端与所述第一终端采用时分复用方式进行通信。
- 一种测井方法,其特征在于,包括:利用权利要求1-8中任一项所述的自适应有线通信方法发送测井数据,其中所述第一终端是井下端,所述第二终端是井上端。
- 一种自适应有线通信***,其特征在于,包括:第一终端和第二终端,其中所述第一终端用于根据通信参数向所述第二终端发送通信数据和训练数据;所述第二终端用于根据所述训练数据对信道通信条件进行评估,并根据评估结果调整发送所述通信数据所采用的通信参数;并将调整后的通信参数发送至所述第一终端。
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CA2984118A CA2984118A1 (en) | 2014-12-30 | 2015-12-29 | Self-adapting wired communication method, well logging method and device |
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CN107610435B (zh) * | 2017-08-18 | 2019-06-18 | 中国科学院地质与地球物理研究所 | 适用于多种类型电缆的高速测井遥传通讯方法 |
CN110080749B (zh) * | 2019-04-08 | 2020-08-28 | 中国科学技术大学 | 一种通用自适应高速测井遥传*** |
CN112671518B (zh) * | 2019-10-14 | 2024-06-21 | 瑞昱半导体股份有限公司 | 通信方法及其装置 |
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CN101015147A (zh) * | 2004-06-29 | 2007-08-08 | 哈里伯顿能源服务公司 | 用于有线油管的井下遥测*** |
CN101226681A (zh) * | 2007-01-18 | 2008-07-23 | 中油测井技术服务有限责任公司 | 使用离散多音频调制方式的测井遥传*** |
CN202850989U (zh) * | 2012-09-21 | 2013-04-03 | 中国海洋石油总公司 | 一种基于单芯测井电缆的高速数据传输*** |
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US6307868B1 (en) * | 1995-08-25 | 2001-10-23 | Terayon Communication Systems, Inc. | Apparatus and method for SCDMA digital data transmission using orthogonal codes and a head end modem with no tracking loops |
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CN101015147A (zh) * | 2004-06-29 | 2007-08-08 | 哈里伯顿能源服务公司 | 用于有线油管的井下遥测*** |
CN101226681A (zh) * | 2007-01-18 | 2008-07-23 | 中油测井技术服务有限责任公司 | 使用离散多音频调制方式的测井遥传*** |
CN202850989U (zh) * | 2012-09-21 | 2013-04-03 | 中国海洋石油总公司 | 一种基于单芯测井电缆的高速数据传输*** |
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