Phase-sensitive detection method and device and logging instrument

Abstract

The invention provides a phase-sensitive detection method and device and a logging instrument. Belongs to the technical field of phase-sensitive detection. The method comprises the following steps: configuring a sampling rate of a system as a target sampling rate, wherein the target sampling rate and a detection frequency of a signal have a specified multiple relationship; acquiring a to-be-detected signal which is acquired based on the target sampling rate and comprises a stratum signal and a noise signal; determining a reference signal generated locally, wherein the amplitude value C of the reference signal is not 0; configuring the phase offset of the reference signal as a target phase offset; determining a cosine sequence and a sine sequence after the reference signal is dispersed according to the target sampling rate based on the reference signal, the to-be-measured signal and the target phase offset; calculating an in-phase component and an orthogonal component of a stratum signal coherent integral based on the cosine sequence and the sine sequence; and calculating the amplitude and the phase of the to-be-measured signal based on the in-phase component and the quadrature component. According to the phase-sensitive detection method, power consumption can be reduced, and meanwhile, the data calculation load is greatly reduced.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of phase-sensitive detection, and particularly to a phase-sensitive detection method, device and logging tool. Background Art

[0002] The logging tool needs to consider reducing the circuit size so as to place more components in a limited space. At the same time, the power consumption of the overall circuit also needs to be considered, because the downhole power is generated by eddy current or battery, and the size of the circuit power consumption directly affects the system stability or battery life. To reduce the circuit board size and the system power consumption at the same time, a key point is to reduce the number of main control chips and reduce the size of the main control chips. Reducing the main control chips also reduces the peripheral circuits of the main control chips, especially the demand for multi-channel power supply. However, reducing the main control chips or replacing them with small-package chips will result in a reduction in logic resources or a significant weakening of the computing power. Summary of the Invention

[0003] The embodiments of the present invention provide a phase-sensitive detection method, device and logging tool that can reduce power consumption and significantly reduce the data calculation load at the same time.

[0004] To solve the above technical problems, the embodiments of the present invention provide a phase-sensitive detection method, which is characterized by including:

[0005] Collecting a signal to be measured including a formation signal and a noise signal;

[0006] Configuring the sampling rate of the system to a target sampling rate, and there is a specified multiple relationship between the target sampling rate and the detection frequency of the signal;

[0007] Obtaining a signal to be measured including a formation signal and a noise signal collected based on the target sampling rate;

[0008] Configuring the phase offset of the reference signal to a target phase offset;

[0009] Determining a cosine sequence and a sine sequence after discretizing the reference signal according to the target sampling rate based on the reference signal, the signal to be measured and the target phase offset, and the values in the cosine sequence and the sine sequence belong to {-C, C} and are not zero;

[0010] Calculating the in-phase component and the quadrature component of the coherent integration of the formation signal based on the cosine sequence and the sine sequence.

[0011] In one embodiment, the configuring the sampling rate of the system to a target sampling rate includes:

[0012] Determining the detection frequency of the signal to be measured;

[0013] Configuring the target sampling rate of the system to 4 times the detection frequency.

[0014] In one embodiment, configuring the phase offset of the reference signal to a target phase offset includes:

[0015] Configuring the phase offset of the reference signal to π / 4.

[0016] In one embodiment, the method further includes:

[0017] Configuring the number of target single - cycle sampling points based on the ratio between the target sampling rate and the detection frequency of the signal, where the number of target single - cycle sampling points is the same as the specified multiple.

[0018] In one embodiment, determining the cosine sequence and sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset includes:

[0019] Determining the cosine sequence and sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, the target phase offset, and the number of target single - cycle sampling points.

[0020] In one embodiment, when the phase offset is π / 4 and the target sampling rate is configured to be 4 times the detection frequency of the signal to be measured, the cosine sequence r I and the sine sequence r Q are respectively:

[0021]

[0022] In one embodiment, calculating the in - phase component I and the quadrature component Q of the coherent integration of the formation signal based on the cosine sequence and the sine sequence includes:

[0023]

[0024] where M is the number of sampling periods of the signal to be measured, k is the sampling point sequence number, and x(·) is the discrete value after system sampling.

[0025] In one embodiment, the method further includes:

[0026] Calculating and determining that the in - phase accumulated data is I_Macc and the quadrature accumulated data is Q_Macc:

[0027]

[0028] Calculating and determining the amplitude A and phase of the signal to be measured based on the in - phase accumulated data and the quadrature accumulated data are respectively:

[0029]

[0030] Among them, θ is the phase offset of the locally generated signal.

[0031] Another embodiment of the present invention also provides a phase-sensitive detection device, including:

[0032] A first configuration module, configured to configure the sampling rate of the system to a target sampling rate, where the target sampling rate has a specified multiple relationship with the detection frequency of the signal;

[0033] An acquisition module, configured to acquire a signal to be measured including a formation signal and a noise signal acquired based on the target sampling rate;

[0034] A determination module, configured to determine a locally generated reference signal, where the amplitude value C of the reference signal is not 0;

[0035] A second configuration module, configured to configure the phase offset of the reference signal to a target phase offset;

[0036] A first calculation module, configured to determine a cosine sequence and a sine sequence after discretizing the reference signal according to the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset, where the values in the cosine sequence and the sine sequence belong to {-C, C} and are both not 0;

[0037] A second calculation module, configured to calculate the in-phase component and the quadrature component of the coherent integration of the formation signal according to the cosine sequence and the sine sequence;

[0038] A third calculation module, configured to calculate the amplitude and phase of the signal to be measured according to the in-phase component and the quadrature component.

[0039] Another embodiment of the present invention also provides a logging tool, including:

[0040] An acquisition device, configured to acquire a signal to be measured including a formation signal and a noise signal;

[0041] A processor, configured to configure the sampling rate of the system to a target sampling rate, where the target sampling rate has a specified multiple relationship with the detection frequency of the signal; acquire the signal to be measured including a formation signal and a noise signal acquired by the acquisition device based on the target sampling rate; determine a locally generated reference signal, where the amplitude value C of the reference signal is not 0; configure the phase offset of the reference signal to a target phase offset; determine a cosine sequence and a sine sequence after discretizing the reference signal according to the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset, where the values in the cosine sequence and the sine sequence belong to {-C, C} and are both not 0; calculate the in-phase component and the quadrature component of the coherent integration of the formation signal based on the cosine sequence and the sine sequence; calculate the amplitude and phase of the signal to be measured based on the in-phase component and the quadrature component.

[0042] Based on the disclosure of the above embodiments, the beneficial effects of the embodiments of the present invention include:

[0043] (1) By designing the sampling rate of the system (acquisition device) to be 4 times the detection frequency, and constructing the local carrier sequence as an alternating symbol equal amplitude coefficient accordingly, a large number of multiply-accumulate algorithms involved in the multiply-accumulate stage in the previous operation process can be replaced by addition and subtraction operations, thus avoiding a large number of multiplication operations, reducing the operation load, and therefore supporting the use of an MCU with weak computing power in the logging tool, expanding the range of selectable chips for the device;

[0044] (2) Support the phase-sensitive detection of the logging tool under high-frequency signals. Since the previous ordinary phase-sensitive detection is limited by multiplication calculations, the sampling frequency cannot be too high. Under the high-speed phase-sensitive detection calculation requirement, it is often necessary to equip a high-performance chip to achieve high-speed ADC sampling and multiplication operations. However, by using the method of this embodiment, only an ordinary-performance chip needs to be configured to complete the high-speed phase-sensitive detection calculation, reducing the device cost and device power consumption, and extending the battery life of the device.

[0045] Other features and advantages of the present application will be described in the subsequent specification, and part of them will become obvious from the specification, or be understood by implementing the present application. The objectives and other advantages of the present application can be realized and obtained through the structures specifically pointed out in the written specification, claims, and drawings.

[0046] The technical solutions of the present application will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0047] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0048] Figure 1 It is a flow schematic diagram of the phase-sensitive detection method in the embodiments of the present invention.

[0049] Figure 2 It is an application flow schematic diagram of the phase-sensitive detection method in the embodiments of the present invention.

[0050] Figure 3 It is a flow structure block diagram of the phase-sensitive detection device in the embodiments of the present invention.

[0051] Figure 4 It is a structural relationship diagram of the logging tool in the embodiments of the present invention. Detailed Embodiments

[0052] Next, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings, but this is not intended to limit the present invention.

[0053] It should be understood that various modifications can be made to the embodiments disclosed herein. Therefore, the following description should not be regarded as limiting, but only as an example of the embodiments. Those skilled in the art will envision other modifications within the scope of the present disclosure.

[0054] The accompanying drawings, which are included in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the general description of the present disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the present disclosure.

[0055] These and other features of the present invention will become apparent from the following description of the preferred forms of the embodiments given by way of non - limiting example with reference to the accompanying drawings.

[0056] It should also be understood that although the present invention has been described with reference to some specific examples, those skilled in the art can surely implement many other equivalent forms of the present invention, which have the features as described in the claims and thus are all within the protection scope defined thereby.

[0057] When combined with the accompanying drawings, the above and other aspects, features, and advantages of the present disclosure will become more apparent in view of the following detailed description.

[0058] Hereinafter, specific embodiments of the present disclosure will be described with reference to the accompanying drawings; however, it should be understood that the disclosed embodiments are merely examples of the present disclosure and can be implemented in various ways. Well - known and / or repetitive functions and structures are not described in detail to avoid obscuring the present disclosure with unnecessary or redundant details. Therefore, the specific structural and functional details disclosed herein are not intended to be limiting, but merely serve as a basis for the claims and a representative basis for teaching those skilled in the art to use the present disclosure in substantially any suitable detailed structure in a variety of ways.

[0059] This specification may use the phrases "in one embodiment", "in another embodiment", "in yet another embodiment", or "in other embodiments", each of which may refer to one or more of the same or different embodiments according to the present disclosure.

[0060] Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0061] In well logging, the transmitting instrument emits different sine signals to the formation, and the changes in the formation are reflected by their variations. The signals received by the acquisition device are composite signals containing various frequencies and noises. It is necessary to extract specific frequency signals from them, measure their amplitude and phase changes, so as to reflect the formation changes. Phase-sensitive detection technology is often used to solve the above problems.

[0062] Phase-sensitive detection needs to complete the multiplication-accumulation operation of data and the square root operation of the final sum of squares data. Generally, the multiplication-accumulation operation needs to be placed in an FPGA or a DSP. Using an FPGA with a multiplier will increase the difficulty of circuit design, increase the circuit size, and it is impossible to achieve miniaturization and low power consumption. If all multiplications and square roots are placed in the MCU, it will occupy a large amount of computing resources of the MCU and affect the real-time performance of control.

[0063] In the past, when well logging instruments performed phase-sensitive detection, the overall method included:

[0064] The measured signal (where n(t) is the system noise, s(t) is the useful signal (i.e., the formation signal), the f of this signal is the frequency of the signal to be measured, which is a known quantity, and the amplitude A and phase are the quantities to be measured in the signal to be measured), locally generate a reference signal r(t) = cos(2π*f*t) + j sin(2π*f*t), t is time, f is frequency, and the cross-correlation result of the measured signal x(t) and the reference signal r(t) is as follows:

[0065]

[0066] R xr (τ) is the cross-correlation function of x(t) and r(t), R nr (τ) is the cross-correlation function of n(t) and r(t), τ is the delay value. Since the noise signal and the reference signal are uncorrelated with each other, so R nr (τ) = 0, R xr (τ) = R sr (τ). Substitute and r(t) = cos(2πft) + j sin(2πft) to get:

[0067]

[0068] When τ = 0, the above formula is simplified to:

[0069] Denote to obtain I is the in-phase component of the coherent integration of the formation signal, Q is the quadrature component of the coherent integration of the formation signal, is the phase of the signal to be measured.

[0070] In engineering practice, an ADC is required to sample signals. Therefore, the above formula needs to be discretized and quantized. In the following formula, x(n) is the discrete value after sampling x(t), and r I (n) and r Q (n) are local signals, that is, reference signals, which are the values after being discretized at the sampling rate (n is the number of sampling times, n = 0, 1, 2,...).

[0071] Let the sampling rate be Fs and the sampling time be Ts, then Fs = 1 / Ts. According to the Nyquist sampling theorem, the sampling rate is at least twice the highest frequency: Fs >= 2f. To avoid calculating the local signal (reference signal) in real time, a lookup table is generally used to obtain the local signal. And Fs is an integer multiple N of f. The waveform period is T = N * Ts. Ts is the system sampling time, such as the ADC sampling time, and Fs = 1 / Ts.

[0072] Discretize the above formula and take τ = 0:

[0073]

[0074] Denote:

[0075] r I (n) = cos(2π * f * nTs)) = cos(2π * n / N))

[0076] r I (n) = sin(2π * f1 * nTs)) = sin(2π * n / N))

[0077] To increase the measurement accuracy, the results of multiple consecutive periods (M ≥ 2) need to be averaged. The orthogonal components of the digital phase-sensitive detection algorithm are respectively:

[0078]

[0079] Among them, M is the number of periods of the measured signal, N is the number of sampling points per period, and n takes values 0, 1, 2,..., M * N - 1.

[0080] Based on the above, it can be known that in the process of calculating I and Q by the traditional method, each contains M * N multiplication calculation steps and M * N - 1 addition steps, totaling 2 * M * N multiplication calculation steps and 2(M * N - 1) addition steps. The calculation amount is extremely large, so a high-performance chip is required to complete this calculation.

[0081] However, for some devices with limited conditions, such as logging tools, etc., it is impossible to complete high-load calculations based on the existing low-performance configurations. To solve this problem, as Figure 1 and Figure 2 shown, this embodiment provides a phase-sensitive detection method, including:

[0082] S1: Configure the sampling rate of the system to be the target sampling rate, where the target sampling rate has a specified multiple relationship with the detection frequency of the signal;

[0083] S2: Obtain a signal to be measured that includes a formation signal and a noise signal and is collected based on the target sampling rate;

[0084] S3: Determine a reference signal generated locally, where the amplitude value C of the reference signal is not 0;

[0085] S4: Configure the phase offset of the reference signal to be the target phase offset;

[0086] S5: Based on the reference signal, the signal to be measured, and the target phase offset, determine the cosine sequence and sine sequence after discretizing the reference signal according to the target sampling rate. The values in the cosine sequence and sine sequence belong to {-C, C} and are both not 0;

[0087] S6: Calculate the in-phase component and quadrature component of the coherent integration of the formation signal based on the cosine sequence and sine sequence;

[0088] S7: Calculate the amplitude and phase of the signal to be measured based on the in-phase component and quadrature component.

[0089] In this embodiment, for the reference signal generated locally, a signal including only one amplitude value C that is not 0 is selected. In this way, the cosine sequence r I and the sine sequence r Q can only be selected from the set {-C, C}. The specific formulas include:

[0090] r I (n, θ) = cos(2π * n / N + θ)

[0091] r Q (n, θ) = sin(2π * n / N + θ)

[0092] N is the number of sampling points in a single period, n is the serial number, and θ is the phase offset of the local reference signal.

[0093] Among them, the 0 term is not included because when it includes the 0 term, the data utilization rate will be reduced. Therefore, in order to utilize all the data in the cosine sequence and sine sequence, in this embodiment, the cosine sequence and sine sequence are designed not to include the 0 term.

[0094] Further, the configuring the sampling rate of the system to be the target sampling rate includes:

[0095] S7: Determine the detection frequency of the signal to be measured;

[0096] S8: Configure the target sampling rate of the system to be 4 times the detection frequency.

[0097] In this embodiment, it is preferably to configure the target sampling rate of the system to be 4 times the detection frequency. For example, configure the target sampling rate of the ADC to be 4 times the detection frequency.

[0098] The method further includes:

[0099] S9: Configure the target number of single - cycle sampling points based on the ratio between the target sampling rate and the detection frequency of the signal, and the target number of single - cycle sampling points is the same as the specified multiple.

[0100] That is, N is 4, and the calculation formula of N is the ratio of the target sampling rate to the detection frequency.

[0101] Configuring the phase offset of the reference signal to be the target phase offset includes:

[0102] S10: Configure the phase offset of the reference signal to be π / 4.

[0103] That is, taking θ as the locally generated signal, including the phase offset of the reference signal, and configuring θ to be π / 4 in this embodiment.

[0104] Based on the above configuration, determining the cosine sequence and sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset includes:

[0105] S11: Determine the cosine sequence and sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, the target phase offset, and the target number of single - cycle sampling points.

[0106] For example, in this embodiment, N = 4 and θ = π / 4 are selected. At this time, based on the foregoing r I and r Q The calculation formula gives:

[0107]

[0108] Factor out the common factor, and the cosine sequence r I and the sine sequence r Q are respectively:

[0109]

[0110] When calculating the in - phase component I and the quadrature component Q of the coherent integration of the formation signal based on the cosine sequence and the sine sequence, the above formula can be substituted into the formula for calculating I, and we get:

[0111]

[0112] Similarly, based on the foregoing formula for Q, we get:

[0113]

[0114] Where M is the number of sampling periods of the signal to be measured, k is the sampling point sequence number, and x(·) is the discrete value after system sampling.

[0115] The multiply-accumulate term in the above-mentioned I Only needs to implement periodic addition and subtraction of data, and there is no need to use a multiplier. Similarly, for the multiply-accumulate term in Q Only periodic addition and subtraction of data is required. That is, through the above method, the multiplication items are greatly reduced, and the in-phase component and the quadrature component can be calculated by changing to addition and subtraction items.

[0116] Furthermore, calculating the amplitude and phase of the signal to be measured according to the in-phase component and the quadrature component includes:

[0117] S11: Calculate and determine that the in-phase accumulated data is I_Macc and the quadrature accumulated data is Q_Macc:

[0118]

[0119] S12: Calculate and determine the amplitude A and phase of the signal to be measured based on the in-phase accumulated data and the quadrature accumulated data Respectively:

[0120]

[0121]

[0122] The is a fixed coefficient, and θ is the phase offset of the locally generated signal.

[0123] Among them, through the above calculation formula of the accumulated data, it can be obtained:

[0124]

[0125] Through the above formulas, only 3 multiplications and one square root operation need to be completed to calculate the amplitude A of the formation signal. And for the formation signal phase, only one division needs to be calculated, and then the required phase information can be obtained through the arctan function. At this time, the calculation of the quantity to be measured in the phase-sensitive detection is completed.

[0126] As can be seen from the content of the above embodiments, the solution designs the sampling rate of the system (such as ADC) to be 4 times the detection frequency, and based on this, a local carrier sequence with alternating signs and equal amplitude coefficients can be constructed. In this way, a large number of multiply-accumulate algorithms involved in the multiply-accumulate stage in the previous operation process can be replaced by addition and subtraction operations, thus avoiding a large number of multiplication operations and reducing the operation load. Therefore, it supports the use of an MCU with weak computing power in the logging tool, expanding the range of chips that can be selected for the device;

[0127] In addition, the above method supports the phase-sensitive detection of the logging tool under high-frequency signals. Since the previous ordinary phase-sensitive detection is limited by multiplication calculations, the sampling frequency cannot be too high. Under the high-speed phase-sensitive detection calculation requirement, high-performance chips are often required to achieve high-speed ADC sampling and multiplication operations. However, by using the method of this embodiment, only ordinary-performance chips need to be configured to complete the high-speed phase-sensitive detection calculation, reducing the equipment cost and power consumption, and extending the battery life of the equipment.

[0128] For example, when this method is applied to a logging instrument, only a CPLD + ordinary MCU or an ordinary MCU needs to be configured to complete the high-speed phase-sensitive detection calculation, without setting high-performance chips. The method described in this application can also be applied to the operation of equipment in high-temperature scenarios. Even if the chip has low computing power, small size, and low power consumption, this kind of equipment can still achieve high-speed phase-sensitive detection.

[0129] As Figure 3 shown, another embodiment of the present invention also provides a phase-sensitive detection device 100 , including:

[0130] A first configuration module, configured to configure the sampling rate of the system to be a target sampling rate, and there is a specified multiple relationship between the target sampling rate and the detection frequency of the signal;

[0131] An acquisition module, configured to acquire a to-be-detected signal including a formation signal and a noise signal collected based on the target sampling rate;

[0132] A determination module, configured to determine a reference signal generated locally, and the amplitude value C of the reference signal is not 0;

[0133] A second configuration module, configured to configure the phase offset of the reference signal to be a target phase offset;

[0134] A first calculation module, configured to determine a cosine sequence and a sine sequence after discretizing the reference signal according to the target sampling rate based on the reference signal, the to-be-detected signal, and the target phase offset. The values in the cosine sequence and the sine sequence belong to {-C, C}, and are both not 0;

[0135] A second calculation module, configured to calculate the in-phase component and the quadrature component of the coherent integration of the formation signal according to the cosine sequence and the sine sequence;

[0136] A third calculation module, configured to calculate the amplitude and the phase of the signal to be measured according to the in-phase component and the quadrature component.

[0137] In one embodiment, configuring the sampling rate of the system to be a target sampling rate includes:

[0138] Determining the detection frequency of the signal to be measured;

[0139] Configuring the target sampling rate of the system to be 4 times the detection frequency.

[0140] In one embodiment, configuring the phase offset of the reference signal to be a target phase offset includes:

[0141] Configuring the phase offset of the reference signal to be π / 4.

[0142] In one embodiment, the device further includes:

[0143] A third configuration module, configured to configure the number of target single-cycle sampling points according to the ratio between the target sampling rate and the detection frequency of the signal, where the number of target single-cycle sampling points is the same as the specified multiple.

[0144] In one embodiment, determining the cosine sequence and the sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset includes:

[0145] Determining the cosine sequence and the sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, the target phase offset, and the number of target single-cycle sampling points.

[0146] In one embodiment, when the phase offset is π / 4 and the target sampling rate is configured to be 4 times the detection frequency of the signal to be measured, the cosine sequence r I and the sine sequence r Q are respectively:

[0147]

[0148] In one embodiment, calculating the in-phase component I and the quadrature component Q of the coherent integration of the formation signal based on the cosine sequence and the sine sequence includes:

[0149]

[0150] where M is the number of sampling periods of the signal to be measured, k is the sampling point sequence number, and x(·) is the discrete value after system sampling.

[0151] In one embodiment, the device further includes:

[0152] A fourth calculation module, configured to calculate and determine that the in-phase accumulation data is I_Macc and the quadrature accumulation data is Q_Macc:

[0153]

[0154] A fifth calculation module, configured to calculate and determine the amplitude of the signal to be measured according to the in-phase accumulation data and the quadrature accumulation data as:

[0155]

[0156] where θ is the phase offset of the locally generated signal.

[0157] As Figure 4 shown, another embodiment of the present invention further provides a logging tool, including:

[0158] An acquisition device, configured to acquire a signal to be measured including a formation signal and a noise signal;

[0159] A processor, configured to configure the sampling rate of the system as a target sampling rate, where the target sampling rate has a specified multiple relationship with the detection frequency of the signal; obtain the signal to be measured including the formation signal and the noise signal acquired by the acquisition device based on the target sampling rate; determine a locally generated reference signal, where the amplitude value C of the reference signal is not 0; configure the phase offset of the reference signal as a target phase offset; determine a cosine sequence and a sine sequence after discretizing the reference signal at the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset, where the values in the cosine sequence and the sine sequence belong to {-C, C} and are both not 0; calculate the in-phase component and the quadrature component of the coherent integration of the formation signal based on the cosine sequence and the sine sequence; calculate the amplitude and phase of the signal to be measured based on the in-phase component and the quadrature component.

[0160] Furthermore, an embodiment of the present invention further provides a storage medium, on which a computer program is stored, and when the program is executed by a processor, the above-mentioned phase-sensitive detection method is implemented. It should be understood that each solution in this embodiment has the corresponding technical effects in the above method embodiment, and will not be elaborated here.

[0161] Furthermore, an embodiment of the present invention further provides a computer program product, which is tangibly stored on a computer-readable medium and includes computer-readable instructions, and when the computer-executable instructions are executed, at least one processor is caused to execute the phase-sensitive detection method in the above-mentioned embodiment.

[0162] It should be noted that the computer storage medium of the present invention can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable medium can, for example, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of the computer-readable storage medium can include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access storage medium (RAM), a read-only storage medium (ROM), an erasable programmable read-only storage medium (EPROM or flash memory), an optical fiber, a portable compact disk read-only storage medium (CD-ROM), an optical storage medium, a magnetic storage medium, or any suitable combination of the above. In the present invention, the computer-readable storage medium can be any tangible medium that contains or stores a program, which can be used by or in conjunction with an instruction execution system, apparatus, or device. And in the present invention, the computer-readable signal medium can include a data signal propagated in a baseband or as part of a carrier wave, which carries the computer-readable program code. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The computer-readable signal medium can also be any computer-readable medium other than the computer-readable storage medium, which can send, propagate, or transmit a program configured to be used by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted by any appropriate medium, including but not limited to: wireless, antenna, optical cable, RF, etc., or any suitable combination of the above.

[0163] In addition, those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage and optical storage, etc.) that contain computer-usable program code.

[0164] The present invention is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowchart and / or block diagram, and the combination of flows and / or blocks in the flowchart and / or block diagram, can be realized by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for realizing the process Figure 1One or more processes and / or blocks Figure 1 A system for the functions specified in one or more blocks

[0165] These computer program instructions can also be stored in a computer-readable memory capable of guiding a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory produce a manufactured article including an instruction system, and the instruction system implements the processes Figure 1 One or more processes and / or blocks Figure 1 The functions specified in one or more blocks

[0166] Those of ordinary skill in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; under the concept of this application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of one or more embodiments of this application as described above, and they are not provided in detail for the sake of brevity.

Claims

1. A phase-sensitive detection method, characterized in that, The method includes: Configuring the sampling rate of the system to a target sampling rate, where the target sampling rate has a specified multiple relationship with the detection frequency of the signal; Obtaining a signal to be measured that includes a formation signal and a noise signal and is collected based on the target sampling rate; Determining a locally generated reference signal, where the amplitude value C of the reference signal is not 0; Configuring the phase offset of the reference signal to a target phase offset; Based on the reference signal, the signal to be measured, and the target phase offset, determining the cosine sequence and sine sequence after the reference signal is discretized at the target sampling rate, where the values in the cosine sequence and sine sequence belong to {-C, C} and are both not 0; Calculating the in-phase component and quadrature component of the coherent integration of the formation signal based on the cosine sequence and sine sequence; Calculating the amplitude and phase of the signal to be measured based on the in-phase component and quadrature component.

2. The phase-sensitive detection method according to claim 1, characterized in that Configuring the sampling rate of the system to a target sampling rate, specifically including: Determining the detection frequency of the signal to be measured; Configuring the target sampling rate of the system to 4 times the detection frequency.

3. The phase-sensitive detection method according to claim 1, characterized in that Configuring the phase offset of the reference signal to a target phase offset, specifically including: Configuring the phase offset of the reference signal to π / 4.

4. The phase-sensitive detection method according to claim 1, characterized in that, The method further includes: Configuring the number of target single-cycle sampling points based on the ratio between the target sampling rate and the detection frequency of the signal, where the number of target single-cycle sampling points is the same as the specified multiple.

5. The phase-sensitive detection method according to claim 4, wherein Based on the reference signal, the signal to be measured, and the target phase offset, determining the cosine sequence and sine sequence after the reference signal is discretized at the target sampling rate, specifically including: Determining the cosine sequence and sine sequence after the reference signal is discretized at the target sampling rate based on the reference signal, the signal to be measured, the target phase offset, and the number of target single-cycle sampling points.

6. The phase-sensitive detection method according to claim 4, wherein When the phase offset is π / 4 and the target sampling rate is configured to be 4 times the detection frequency of the signal under test, the cosine sequence r I and the sine sequence r Q are respectively:

7. The phase-sensitive detection method according to claim 1, wherein Calculating the in-phase component I and quadrature component Q of the coherent integration of the signal to be measured based on the cosine sequence and sine sequence, specifically including: Where M is the number of sampling periods of the signal to be measured, k is the sampling point serial number, and x(·) is the discrete value after system sampling.

8. The phase-sensitive detection method according to claim 7, characterized in that, Calculating the amplitude and phase of the signal to be measured based on the in-phase component and quadrature component, specifically including: Determining the in-phase accumulated data as I_Macc and the quadrature accumulated data as Q_Macc based on the in-phase component and quadrature component; where: Calculate the amplitude A and phase of the signal to be measured based on the in-phase accumulated data and quadrature accumulated data They are respectively: Where θ is the phase offset of the locally generated signal.

9. A phase-sensitive detection device, characterized in that, The device includes: A first configuration module, configured to configure the sampling rate of the system to a target sampling rate, where the target sampling rate has a specified multiple relationship with the detection frequency of the signal; An obtaining module, configured to obtain a signal to be measured that includes a formation signal and a noise signal and is collected based on the target sampling rate; A determining module, configured to determine a locally generated reference signal, where the amplitude value C of the reference signal is not 0; A second configuration module, configured to configure the phase offset of the reference signal to a target phase offset; A first calculation module, configured to determine the cosine sequence and sine sequence after the reference signal is discretized at the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset, where the values in the cosine sequence and sine sequence belong to {-C, C} and are both not 0; A second calculation module, configured to calculate an in-phase component and a quadrature component of coherent integration of the formation signal according to the cosine sequence and the sine sequence; A third calculation module, configured to calculate an amplitude and a phase of the signal to be measured according to the in-phase component and the quadrature component.

10. A logging tool, characterized in that, The logging tool includes: An acquisition device, configured to acquire a signal to be measured including a formation signal and a noise signal; A processor, configured to configure a sampling rate of the system as a target sampling rate, where the target sampling rate has a specified multiple relationship with a detection frequency of the signal; obtain the signal to be measured including the formation signal and the noise signal acquired by the acquisition device based on the target sampling rate; determine a reference signal generated locally, where an amplitude value C of the reference signal is not 0; configure a phase offset of the reference signal as a target phase offset; determine a cosine sequence and a sine sequence after discretization of the reference signal according to the target sampling rate based on the reference signal, the signal to be measured, and the target phase offset, where values in the cosine sequence and the sine sequence belong to {-C, C} and are both not 0; calculate an in-phase component and a quadrature component of coherent integration of the formation signal according to the cosine sequence and the sine sequence; calculate an amplitude and a phase of the signal to be measured according to the in-phase component and the quadrature component.

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