Signal-to-noise ratio adjustment device, method, system and storage medium

Abstract

The present application discloses a signal-to-noise ratio adjustment device, method, system and storage medium, and relates to the technical field of signal demodulation, comprising: performing zero-point tracking on a connected resolver sine signal and a resolver cosine signal through an adaptive zero-delta-sigma modulator, setting the zero point at a target frequency of the resolver sine signal and the target frequency of the resolver cosine signal, thereby reducing the noise component of the connected resolver sine signal and the resolver cosine signal at the target frequency, that is, reducing the noise component of the connected resolver sine signal and the resolver cosine signal at a high frequency, so that the noise component on the output signal output by the adaptive zero-delta-sigma modulator becomes smaller, and in the process of inputting the output signal into a demodulator for demodulation, the noise component moved to the low-frequency signal of the demodulated signal will also become smaller, thereby improving the signal-to-noise ratio of the demodulated signal, and achieving the signal-to-noise ratio adjustment effect.

Description

Technical Field

[0001] The present application relates to the technical field of signal demodulation, and in particular to a signal-to-noise ratio adjustment device, method, system and storage medium. Background Art

[0002] The rotary digital converter synchronously collects the sine signal and cosine signal and sends them to the analog-to-digital converter of the Delta Sigma (delta-sigma) modulator respectively. At this time, the Delta Sigma modulator will convert the continuous input signal into a discrete output signal. Due to the noise shaping of the analog-to-digital converter, there is a large noise component at the high frequency of the output signal.

[0003] During the demodulation process of the output signal, the existing noise components will move with the frequency. Therefore, the noise components of the output signal will move to the low-frequency signal of the demodulated signal, resulting in aliasing of the signal at the low-frequency signal and the noise at the high-frequency signal, and then the output demodulated signal will have a poor signal-to-noise ratio problem. Summary of the invention

[0004] The main purpose of the present application is to provide a signal-to-noise ratio adjustment device, method, system and storage medium, aiming to solve the technical problem that the output signal of the conventional demodulated signal has a poor signal-to-noise ratio.

[0005] To achieve the above-mentioned object, the present application proposes a signal-to-noise ratio adjustment device, which includes an adaptive zero-delta-sigma modulator, a demodulator, a second-order tracking loop, a first oscillator and a second oscillator;

[0006] The output end of the adaptive zero-delta-sigma modulator is connected to the input end of the demodulator, and is used to send an output signal to the demodulator according to the input resolver sine signal and resolver cosine signal;

[0007] The output end of the demodulator is connected to the input end of the second-order tracking loop and the input end of the adaptive zero-delta-sigma modulator, and is used to output an angle error value to the second-order tracking loop and the adaptive zero-delta-sigma modulator according to the input output signal, the sine output angle, the cosine output angle and the sine excitation angle, wherein the angle error value is the angle value of the input shaft angle minus the output angle;

[0008] The output end of the second-order tracking loop is connected to the input end of the second oscillator and the input end of the adaptive zero-delta-sigma modulator, and is used to send the output angle to the second oscillator and the adaptive zero-delta-sigma modulator according to the input angle error value;

[0009] The output end of the second oscillator is connected to the input end of the demodulator, and is used to output a sine output angle and a cosine output angle to the demodulator according to the output angle;

[0010] The output end of the first oscillator is connected to the input end of the demodulator, and is used to output a sinusoidal excitation angle to the demodulator according to the input excitation parameters;

[0011] The adaptive zero-point incremental sigma modulator is also used to perform zero-point tracking on the resolver sine signal and the resolver cosine signal according to the output angle and the excitation parameters when it is determined that there is a need for zero-point adjustment based on the angle error value, so as to reduce the noise component on the resolver sine signal and the resolver cosine signal.

[0012] The present application also proposes a signal-to-noise ratio adjustment method, which is applied to the above signal-to-noise ratio adjustment device, and is characterized in that the signal-to-noise ratio adjustment method includes:

[0013] The zero point tracking of the resolver sine signal and the resolver cosine signal is performed through an adaptive zero-point delta-sigma modulator, and the zero point is set at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal to reduce the noise component on the resolver sine signal and the resolver cosine signal.

[0014] In one embodiment, before the step of performing zero point tracking on the resolver sine signal and the resolver cosine signal, the method includes:

[0015] Calculate the angle error between the input shaft angle and the output angle through the adaptive zero-point incremental accumulator, and determine whether the angle error value is less than a preset error threshold;

[0016] If the angle error value is determined to be less than a preset error threshold, the adaptive zero-point incremental-accumulative modulator is controlled to start a zero-point tracking function;

[0017] If it is determined that the angle error value is greater than a preset error threshold, the adaptive zero-point incremental-accumulative modulator is controlled to turn off the zero-point tracking function.

[0018] In one embodiment, the zero point tracking function is in a turned-on state, and the zero point is correlated with the signal frequency and the output angle.

[0019] In one embodiment, when the delta-sigma modulator included in the adaptive zero-point delta-sigma modulator is a third-order delta-sigma modulator, the zero point includes a first zero point, a second zero point, and a third zero point, and the step of setting the zero point at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal includes:

[0020] Setting the first zero point at the DC frequency of the resolver sine signal and the DC frequency of the resolver cosine signal, setting the second zero point at the positive signal frequency of the resolver sine signal and the positive signal frequency of the resolver cosine signal, and setting the third zero point at the negative signal frequency of the resolver sine signal and the negative signal frequency of the resolver cosine signal;

[0021] Among them, the DC frequency, the positive signal frequency and the negative signal frequency are the target frequencies.

[0022] In one embodiment, when the delta-sigma modulator is a fifth-order delta-sigma modulator, the zero points include a first zero point, a second zero point, a third zero point, a fourth zero point, and a fifth zero point, and the step of setting the zero points at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal includes:

[0023] Setting a first zero point at a DC frequency of a resolver sine signal and a DC frequency of a resolver cosine signal, setting a second zero point at a first positive frequency of a resolver sine signal and a first positive frequency of a resolver cosine signal, setting a third zero point at a second positive frequency of a resolver sine signal and a second positive frequency of a resolver cosine signal, setting a fourth zero point at a first negative frequency of a resolver sine signal and a first negative frequency of a resolver cosine signal, and setting a fifth zero point at a second negative frequency of a resolver sine signal and a second negative frequency of a resolver cosine signal;

[0024] Among them, the DC frequency, the first positive frequency, the second positive frequency, the first negative frequency and the second negative frequency are target frequencies.

[0025] In one embodiment, the first positive frequency is the sum of the excitation frequency and the rotation frequency in the positive direction of the horizontal axis, and the second positive frequency is the difference between the excitation frequency and the rotation frequency in the positive direction of the horizontal axis;

[0026] The first negative frequency is the sum of the excitation frequency and the rotation frequency in the negative direction of the horizontal axis, and the second negative frequency is the difference between the excitation frequency and the rotation frequency in the negative direction of the horizontal axis.

[0027] In one embodiment, after the step of setting the zero point at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal, the method further includes:

[0028] Obtaining a sine output signal and a cosine output signal, and inputting the sine output signal into a first multiplier to multiply it with the cosine signal to obtain a first signal to be output, and inputting the cosine output signal into a second multiplier to multiply it with the sine signal to obtain a second signal to be output;

[0029] The first signal to be output and the second signal to be output are input into the first adder for subtraction to obtain an excitation signal, and then the excitation signal is input into the third multiplier to be multiplied with the modulation signal to output a demodulated signal.

[0030] In addition, to achieve the above-mentioned purpose, the present application also proposes a signal-to-noise ratio adjustment system, which includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the signal-to-noise ratio adjustment method described above.

[0031] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the signal-to-noise ratio adjustment method described above are implemented.

[0032] One or more technical solutions proposed in this application have at least the following technical effects:

[0033] A signal-to-noise ratio adjustment device is proposed. The signal-to-noise ratio adjustment device is provided with an adaptive zero-delta-sigma modulator, a demodulator, a second-order tracking loop, a first oscillator and a second oscillator. The adaptive zero-delta-sigma modulator is used to perform zero-point tracking on a connected resolver sine signal and a resolver cosine signal, and the zero point is set at a target frequency of the resolver sine signal and a target frequency of the resolver cosine signal, so as to reduce the noise component of the connected resolver sine signal and the resolver cosine signal at the target frequency, that is, to reduce the noise component of the connected resolver sine signal and the resolver cosine signal at a high frequency, so that the noise component on the output signal output by the adaptive zero-delta-sigma modulator becomes smaller. Correspondingly, in the process of inputting the output signal into the demodulator for demodulation, the noise component moved to the low-frequency signal of the demodulated signal will also become smaller, thereby avoiding the situation that the signal at the low-frequency signal and the noise at the high-frequency signal are aliased, improving the signal-to-noise ratio of the demodulated signal, and achieving the signal-to-noise ratio adjustment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0035] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0036] Figure 1 This is a schematic diagram of the structure of the signal-to-noise ratio adjustment device of this application;

[0037] Figure 2 This is a schematic diagram of an embodiment of an adaptive zero-delta-sigma modulator of the present application;

[0038] Figure 3 It is a schematic diagram of the working principle of the rotary digitizer;

[0039] Figure 4A schematic diagram of frequency analysis when demodulating an output signal output by an analog-to-digital converter based on a Delta Sigma modulator;

[0040] Figure 5 Schematic diagram of the linear model of a first-order Delta Sigma modulator;

[0041] Figure 6 Schematic diagram of the linear model of the third-order Delta Sigma modulator;

[0042] Figure 7 It is a schematic diagram of the signal frequency based on the third-order delta-sigma modulator without zero-point tracking;

[0043] Figure 8 It is a schematic diagram of signal frequency under zero-point tracking based on a third-order delta-sigma modulator;

[0044] Fig. 9 It is a schematic diagram of signal frequency under zero-point tracking based on a fifth-order delta-sigma modulator;

[0045] Fig.10 Schematic diagram of the device structure of the hardware operating environment involved in the signal-to-noise ratio adjustment method in the embodiment of the present application.

[0046] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0047] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0048] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0049] The main solution of the embodiment of the present application is: through an adaptive zero-point delta-sigma modulator, zero-point tracking is performed on the resolver sine signal and the resolver cosine signal, and the zero point is set at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal to reduce the noise component on the resolver sine signal and the resolver cosine signal.

[0050] The rotary digital converter synchronously collects sine and cosine signals and sends them to the analog-to-digital converter of the Delta Sigma modulator. At this time, the Delta Sigma modulator converts the continuous input signal into a discrete output signal. Due to the noise shaping of the analog-to-digital converter, there is a large noise component at the high frequency of the output signal. During the demodulation process of the output signal, the existing noise component will move with the frequency, so the noise component of the output signal will move to the low-frequency signal of the demodulated signal, resulting in the signal at the low-frequency signal and the noise at the high-frequency signal being aliased, and then the output demodulated signal has a poor signal-to-noise ratio.

[0051] The present application provides a solution, by proposing a signal-to-noise ratio adjustment device, in which an adaptive zero-delta-sigma modulator, a demodulator, a second-order tracking loop, a first oscillator and a second oscillator are provided. The adaptive zero-delta-sigma modulator is used to perform zero-point tracking on the connected resolver sine signal and resolver cosine signal, and the zero point is set at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal, so as to reduce the noise component of the connected resolver sine signal and resolver cosine signal at the target frequency, that is, to reduce the noise component of the connected resolver sine signal and resolver cosine signal at the high frequency, so that the noise component on the output signal output by the adaptive zero-delta-sigma modulator becomes smaller, and correspondingly, in the process of inputting the output signal into the demodulator for demodulation, the noise component moved to the low-frequency signal of the demodulated signal will also become smaller, thereby avoiding the situation where the signal at the low-frequency signal and the noise at the high-frequency signal are aliased, improving the signal-to-noise ratio of the demodulated signal, and achieving the signal-to-noise ratio adjustment effect.

[0052] It should be noted that the execution subject of this embodiment may be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, etc. The following takes the signal-to-noise ratio adjustment system as an example to illustrate this embodiment and the following embodiments.

[0053] Based on this, the embodiment of the present application provides a signal-to-noise ratio adjustment device, referring to Figure 1 and Figure 2 , Figure 1 This is a module schematic diagram of the signal-to-noise ratio adjustment device of this application. Figure 2 The schematic diagram of the module of the adaptive zero-delta-sigma modulator.

[0054] In this embodiment, the signal-to-noise ratio adjustment device includes an adaptive zero-delta-sigma modulator (i.e. Figure 1 Adaptive zero-point DSM in), demodulator, second-order tracking loop, first oscillator (i.e. Figure 1 Oscillator 1 in the Figure 1 Oscillator 2 in );

[0055] The output end of the adaptive zero-delta-sigma modulator is connected to the input end of the demodulator, and is used to send an output signal (i.e. Figure 1 In and ) to the demodulator;

[0056] The output end of the demodulator is connected to the input end of the second-order tracking loop and the input end of the adaptive zero-delta-sigma modulator, and is used to adjust the output signal and the sinusoidal output angle (i.e. Figure 1 In ), cosine output angle (i.e. Figure 1 In ) and the sinusoidal excitation angle (i.e. Figure 1 In ), output angle error value (i.e. Figure 1 In ) to the second-order tracking loop and the adaptive zero-delta-sigma modulator, wherein the angle error value is the input shaft angle Subtract output angle The angle value of

[0057] The output end of the second-order tracking loop is connected to the input end of the second oscillator and the input end of the adaptive zero-delta-sigma modulator, and is used to output the output angle to the second oscillator and the adaptive zero-delta-sigma modulator according to the angle error value connected;

[0058] The output end of the second oscillator is connected to the input end of the demodulator, and is used to output the sine output angle and the cosine output angle to the demodulator according to the output angle. The output end of the first oscillator is connected to the input end of the demodulator, and is used to output the sine output angle and the cosine output angle to the demodulator according to the input excitation parameter. , outputs a sinusoidal excitation angle to the demodulator, where, It is used for zero point adjustment, so it can also be an excitation phase, and the first oscillator and the second oscillator can be either analog oscillators or digital oscillators, and can also be implemented using the LUT lookup method or the CORDIC method.

[0059] The adaptive zero-point incremental sigma modulator is further used to perform zero-point tracking on the resolver sine signal and the resolver cosine signal according to the output angle and the excitation parameter when it is determined that there is a zero-point adjustment requirement according to the angle error value, so as to reduce the noise component on the resolver sine signal and the resolver cosine signal, that is, when it is determined that there is a zero-point adjustment requirement according to the angle error value, the output angle is adjusted by closing the switch through the zero-point control. and excitation parameters The signal is transmitted to the Delta Sigma modulator to track the zero point of the resolver sine signal and resolver cosine signal in the Delta Sigma modulator. Figure 2 As shown, when the output angle is Angle with input shaft When the phase difference is large, the zero-point tracking function of the noise transfer function NTF is not enabled, that is, the zero-point regulator is not transferred to the delta-sigma modulator (i.e. Figure 2 The connection switch between the Delta Sigma modulator in the output angle is turned on. At this time, the delta-sigma modulator does not have the zero tracking function. Angle with input shaft When the error is small enough, the zero-point tracking function of the noise transfer function NTF is turned on, that is, the connection switch between the zero-point regulator and the incremental-sigma modulator is turned on. At this time, the incremental-sigma modulator has the zero-point tracking function.

[0060] In addition, in addition to controlling the zero point by angle error, other methods can also be used, such as control related to other detection methods, or using a register to control the switch to be normally open or normally closed.

[0061] Among them, Similarly, the input to the delta-sigma modulator is used for zero point adjustment. , which can be either the rotor speed or the rotor phase.

[0062] It should be noted that the adaptive zero-delta-sigma modulator in this embodiment includes a Delta Sigma modulator, and the demodulator is a rotary digital converter.

[0063] Reference Figure 3 The working principle of the rotary digital converter shown in the figure, the resolver uses a sine wave reference signal The primary winding is excited, which will generate two electromagnetic induction differential output signals on the secondary winding, which are sinusoidal signals and cosine signal The rotary digital converter, which interfaces between the resolver and the system microprocessor, uses these sine and cosine signals to decode the angular position and rotational speed of the motor shaft.

[0064] The rotary digital converter synchronously collects the above sine and cosine signals and transmits them to the analog-to-digital converter of the DeltaSigma modulator respectively, and outputs discrete output signals, namely Figure 3 The sinusoidal output signal in Sum and cosine output signals Since the sine output signal and the cosine output signal have been subjected to noise shaping by the analog-to-digital converter, the noise components at the high frequencies of the sine output signal and the cosine output signal are relatively large.

[0065] in addition, Figure 3 In is generated by the internal clock module, and its frequency is known. and signal Output angle in is generated by the internal second-order tracking rotation loop, the output angle Used to track the input shaft angle . And the signal - and signal In , used to represent the output angle and input shaft angle The amount of error between .

[0066] Reference Figure 4 The frequency analysis of the output signal of the analog-to-digital converter based on the Delta Sigma modulator shown in the figure shows that, assuming the output angle and input shaft angle There is a 90° error between them.

[0067] As the signal spectrum shifts, the noise will also shift. Therefore, with the demodulation operation, the noise component at the low frequency will become larger as the spectrum shifts. And the larger the frequency, the greater the spectrum shift, and the greater the noise shift. Therefore, the higher frequency noise will be mixed with the low frequency signal component, resulting in a worse signal-to-noise ratio of the final output demodulated signal.

[0068] also, The noise at the 1 / 4 signal component is essentially the same as the noise at the higher frequency signal component of the sinusoidal output signal. The noise at the 1 / 4 signal component is roughly equal to the noise at the higher frequency signal component of the cosine output signal. - Is and This operation will make the signal perform a subtraction operation, but because the noise is uncorrelated, it cannot be directly added or subtracted. It can only be squared and added. Therefore, although the signal - The signal component in the subtraction operation is performed, but the noise component is squared and added, so the signal - The noise floor is higher. Noise at DC, similar to signal - The noise at all signal components is basically equal.

[0069] It can be concluded that due to the influence of the noise shaping of the analog-to-digital converter, the noise components at the high frequencies of the sine output signal and the cosine output signal are relatively large, and as the sine output signal and the cosine output signal are input into the rotary digital converter for demodulation, the frequency will be shifted and the noise will also be shifted. Therefore, the noise at the 1 / 4 signal component of the sine output signal and the cosine output signal will be shifted to the low-frequency signal of the final result, resulting in aliasing of the low-frequency signal and the high-frequency noise, which will lead to a deterioration of the final signal-to-noise ratio.

[0070] Based on the above problems, this embodiment proposes to use a Delta Sigma modulator to perform zero-point tracking on the input signal, that is, the sine signal and the cosine signal. The principle is as follows:

[0071] Reference Figure 5 The linear model of the first-order Delta Sigma modulator is shown. The input signal With signal After adding, input Multiply in and output the signal ,Right now ,in, is the signal transfer function STF, is the noise transfer function NTF. It can be obtained that STF is the delay characteristic, NTF is the high-pass characteristic, and the input signal Only a delay is made, and the noise is shaped so that a large amount of noise can pass at high frequencies, that is, the noise at low frequencies is very small, and the noise at high frequencies is very large.

[0072] Reference Figure 6 The linear model of the third-order Delta Sigma modulator is shown. The input signal With signal After adding, input into Multiply in and output the signal ,Right now ,in, is the signal transfer function STF, is the noise transfer function NTF. It can be seen that the signal transfer function of the third-order Delta Sigma modulator is the same as that of the first-order Delta Sigma modulator, and the base of the noise transfer function is , whose power is the same as the order of the Delta Sigma modulator.

[0073] In addition, for a first-order Delta Sigma modulator, at DC , that is, there is a zero point at the DC frequency. For a third-order Delta Sigma modulator, the noise transfer function is , that is, there are three zero points at the DC frequency, and the existence of zero points means that the noise at that frequency approaches 0.

[0074] That is, in this embodiment, by changing the noise transfer function NTF of the Delta Sigma modulator, the zero points no longer exist only at the DC frequency of the signal, but a part of the zero points are correlated with the signal frequency and output angle of the input signal, enabling it to track the changes of the signal frequency and output angle, and setting the zero points at the target frequency of the input signal, so that the noise at the target frequency approaches 0, that is, reducing the large noise component of the input signal at high frequencies, and thus avoiding the deterioration of the signal-to-noise ratio of the demodulated signal caused by noise migration.

[0075] Based on this, the embodiment of the present application provides a signal-to-noise ratio adjustment method. In this embodiment, the signal-to-noise ratio adjustment method includes step S10:

[0076] Step S10, through an adaptive zero-point increment accumulator modulator, perform zero-point tracking on the resolver sine signal and the resolver cosine signal, and set the zero points at the target frequencies of the resolver sine signal and the resolver cosine signal to reduce the noise components on the resolver sine signal and the resolver cosine signal.

[0077] Through the adaptive zero-point increment accumulator modulator, perform zero-point tracking on the input resolver sine signal and resolver cosine signal, enabling it to track the changes between the excitation parameters and the output angle, and set the zero points at the target frequencies corresponding to the resolver sine signal and the resolver cosine signal respectively, thereby reducing the amplitudes of the signal components and noise components at the target frequencies, and further reducing the noise components on the output signal, and improving the signal-to-noise ratio of the demodulated signal output by the demodulator based on this output signal.

[0078] In a feasible implementation manner, before step S10, it includes steps S01~S03:

[0079] Step S01, through the adaptive zero-point increment accumulator modulator, calculate the angle error value between the input shaft angle and the output angle, and determine whether the angle error value is less than a preset error threshold.

[0080] Step S02, if it is determined that the angle error value is less than the preset error threshold, then control the adaptive zero-point increment accumulator modulator to turn on the zero-point tracking function.

[0081] Step S03, if it is determined that the angle error value is greater than the preset error threshold, then control the zero-point tracking function of the adaptive zero-point increment accumulator modulator.

[0082] It should be noted that the zero-point tracking function in this embodiment is only enabled when the angular error between the input shaft angle and the output angle is less than a preset error threshold, so as to ensure the effectiveness of the zero-point tracking. When the error between the input shaft angle and the output angle is greater than the preset error threshold, the signal conditioner only has ordinary functions.

[0083] In a feasible implementation, step S10 may include step S11:

[0084] Step S11, setting the first zero point at the DC frequency of the resolver sine signal and the DC frequency of the resolver cosine signal, setting the second zero point at the positive signal frequency of the resolver sine signal and the positive signal frequency of the resolver cosine signal, and setting the third zero point at the negative signal frequency of the resolver sine signal and the negative signal frequency of the resolver cosine signal; wherein the DC frequency, the positive signal frequency, and the negative signal frequency are the target frequencies.

[0085] Reference Figure 8 As shown, the sinusoidal output signal For example, if the delta-sigma modulator is a third-order delta-sigma modulator, there will be three zeros, namely the first zero (i.e. Figure 8 S1 in), the second zero point (i.e. Figure 8 S2 in the Figure 8 The first zero point is located at the DC frequency, while the second and third zero points are located at ± At the positive signal frequency and the negative signal frequency, the sine output signal output by the delta-sigma modulator is at the 1 / 4 signal component, that is, and- The noise at the Figure 7 By comparing the sinusoidal output signal without zero point tracking, it can be found that the noise component of the sinusoidal output signal after zero point tracking is significantly smaller than the noise component of the sinusoidal output signal without zero point tracking.

[0086] It should be noted that Figure 8 and Figure 7 The third-order zero-tracking DSM output and the third-order zero-tracking DSM output are signal 1, and the output after rotation demodulation is signal - The phase error signal input to the type II loop is , by comparison, Figure 8 The sinusoidal output signal in Figure 7 The sinusoidal output signal in has a lower noise floor; as can be seen from the arrow, Figure 8 The signal in Compared to Figure 7 The signal in , its signal-to-noise ratio is better.

[0087] The quantization noise migration process of the RDC architecture of the third-order zero-tracking DSM can be referred to Figure 8 As shown in the figure, it can be seen that for the DSM without zero tracking, all three zero points are at the DC frequency, and the final demodulation result has a noise power of approximately -116dB.

[0088] The quantization noise migration process of the RDC architecture of the third-order zero-tracking DSM can be referred to Fig. 9 As shown in the figure, it can be seen that the three zero points of the third-order zero-point tracking DSM are respectively at the negative excitation frequency, DC frequency, and positive excitation frequency from left to right. The final demodulation result, the noise power is about -124dB. It is about 8dB smaller than the noise power of the third-order non-zero-point tracking DSM.

[0089] In another feasible implementation manner, step S10 may further include step S12:

[0090] Step S12, setting the first zero point at the DC frequency of the resolver sine signal and the DC frequency of the resolver cosine signal, setting the second zero point at the first positive frequency of the resolver sine signal and the first positive frequency of the resolver cosine signal, setting the third zero point at the second positive frequency of the resolver sine signal and the second positive frequency of the resolver cosine signal, setting the fourth zero point at the first negative frequency of the resolver sine signal and the first negative frequency of the resolver cosine signal, and setting the fifth zero point at the second negative frequency of the resolver sine signal and the second negative frequency of the resolver cosine signal; wherein the DC frequency, the first positive frequency, the second positive frequency, the first negative frequency and the second negative frequency are the target frequencies.

[0091] Reference Fig. 9 As shown, take the sinusoidal output signal as an example. If the delta-sigma modulator is a fifth-order delta-sigma modulator, there will be five zero points, namely the first zero point (i.e. Fig. 9 S1 in), the second zero point (i.e. Fig. 9 S2 in), the third zero point (i.e. Figure 1 S3 in), the fourth zero point (i.e. Fig. 9 S4 in the Fig. 9 S5 in ). The first zero point is located at the DC frequency, and the second to fifth zero points are located at and- Because the error between the output angle and the input shaft angle is less than the preset error threshold, the output angle can be approximated to the input shaft angle, that is, the second zero point to the fifth zero point can be regarded as being located at and- At this point, the sinusoidal output signal of the delta-sigma modulator is at the 1 / 4 signal component, that is, and- The noise at the Figure 8 By comparing the sinusoidal output signal with zero-point tracking under a third-order delta-sigma modulator, it can be seen that the noise component of the sinusoidal output signal after zero-point tracking under a fifth-order delta-sigma modulator is significantly smaller than the noise component of the sinusoidal output signal with zero-point tracking under a third-order delta-sigma modulator.

[0092] It should be noted that Fig. 9 The output of the fifth-order zero-tracking DSM is a sinusoidal output signal, and the output after rotation demodulation is the signal - The phase error signal input to the type II loop is , by comparison, Fig. 9 The sinusoidal output signal in Figure 7 The sinusoidal output signal in has a lower noise floor; as can be seen from the arrow, Fig. 9 The signal in Compared to Figure 7 The signal in , its signal-to-noise ratio is better.

[0093] The schematic diagram of the quantization noise transfer process of the RDC architecture of the fifth-order zero-tracking DSM shows that the noise power of the final demodulation result is about -164dB. This is about 40dB smaller than the noise power of the third-order zero-tracking DSM. Figures 7 to 9 The vertical axis is power and the horizontal axis is frequency.

[0094] It is worth noting that the RDC architecture of the third-order zero-point tracking DSM and the RDC architecture of the fifth-order zero-point tracking DSM are relatively typical. However, DSMs of other orders can also realize the zero-point tracking function. For example, the third-order zero-point tracking DSM, if the zero point at the DC frequency is removed, becomes a second-order bandpass DSM. In addition, the fifth-order zero-point tracking DSM, if the zero point at the DC frequency is removed, becomes a fourth-order bandpass DSM, both of which can realize the zero-point tracking function.

[0095] In a feasible implementation manner, step S10 may further include steps S20-S21:

[0096] Step S20, obtaining a sine output signal and a cosine output signal, and inputting the sine output signal into a first multiplier to multiply it with the cosine signal to obtain a first signal to be output, and inputting the cosine output signal into a second multiplier to multiply it with the sine signal to obtain a second signal to be output;

[0097] Step S21, the first signal to be output and the second signal to be output are input into the first adder for subtraction, and after obtaining the excitation signal, the excitation signal is input into the third multiplier, multiplied with the modulation signal, and the demodulated signal is output.

[0098] Combination Figure 3 Explanation: The sinusoidal output signal after zero point tracking Sum and cosine output signals As the output signal of the demodulator, it is input into the first multiplier ① and the second multiplier ② corresponding to the demodulator, and the cosine signal connected to the first multiplier ① The sine signal connected to the second multiplier ② Multiply by to get the first output signal and the second output signal After that, the two signals to be output are sent to the first adder ③ for subtraction to obtain the excitation signal , the excitation signal Sent to the third multiplier ④ and modulated signal Multiply and get the demodulated signal , simplify the demodulated signal and get the demodulated signal .

[0099] Because the sinusoidal output signal after zero point tracking Sum and cosine output signals The noise component at the corresponding target frequency is reduced, so the amount of noise introduced by spectrum shifting during the demodulation operation by the demodulator is also reduced, thereby improving the signal-to-noise ratio of the demodulated signal.

[0100] In this embodiment, the signal frequency and output angle in the input signal are zero-tracked through an incremental sigma modulator, and the zero point is set at the target frequency of the input signal to generate an output signal; the output signal is accessed based on a demodulator, and the output signal is demodulated and a demodulated signal is output, so as to lower the amplitude of the signal component and the noise component at the target frequency, thereby reducing the noise component on the output signal, and improving the signal-to-noise ratio of the demodulated signal output by the demodulator when demodulating based on the output signal.

[0101] The present application provides a signal-to-noise ratio adjustment system, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor, so that the at least one processor can execute the signal-to-noise ratio adjustment method in the above-mentioned embodiment 1.

[0102] Reference below Fig.10 , which shows a schematic diagram of the structure of the signal-to-noise ratio adjustment system suitable for implementing the embodiment of the present application. The signal-to-noise ratio adjustment system in the embodiment of the present application may include but is not limited to mobile terminals such as laptop computers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions: tablet computers), PMPs (Portable Media Players: portable multimedia players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Fig.10 The signal-to-noise ratio adjustment system shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0103] like Fig.10 As shown, the signal-to-noise ratio adjustment system may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the signal-to-noise ratio adjustment system are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the signal-to-noise ratio adjustment system to communicate with other devices wirelessly or wired to exchange data. Although the figure shows a signal-to-noise ratio adjustment system with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0104] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0105] The signal-to-noise ratio adjustment system provided by the present application adopts the signal-to-noise ratio adjustment method in the above embodiment, which can solve the technical problem that the output signal of the conventional demodulated output signal has a poor signal-to-noise ratio. Compared with the prior art, the beneficial effects of the signal-to-noise ratio adjustment system provided by the present application are the same as the beneficial effects of the signal-to-noise ratio adjustment method provided by the above embodiment, and other technical features of the signal-to-noise ratio adjustment system are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0106] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0107] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0108] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the signal-to-noise ratio adjustment method in the above-mentioned embodiment.

[0109] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency: Radio Frequency), etc., or any suitable combination of the above.

[0110] The computer-readable storage medium may be included in the signal-to-noise ratio adjustment system; or may exist independently without being assembled into the signal-to-noise ratio adjustment system.

[0111] The computer-readable storage medium carries one or more programs. When the one or more programs are executed by the signal-to-noise ratio adjustment system, the signal-to-noise ratio adjustment system: performs zero-point tracking on the signal frequency and output angle in the input signal through an incremental sigma modulator, sets the zero point at the target frequency of the input signal, and generates an output signal; accesses the output signal based on a demodulator, demodulates the output signal, and outputs a demodulated signal.

[0112] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0113] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0114] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0115] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned signal-to-noise ratio adjustment method, and can solve the technical problem that the output signal of the conventional demodulated output signal has a poor signal-to-noise ratio. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the signal-to-noise ratio adjustment method provided in the above-mentioned embodiment, and will not be described in detail here.

[0116] The above are only some embodiments of the present application, and thus do not limit the patent scope of the present application. Any equivalent structural transformation made under the technical concept of the present application by using the content of the specification and drawings of the present application, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present application.

Claims

1. A signal-to-noise ratio adjustment device, characterized in that: The signal-to-noise ratio adjustment device includes an adaptive zero-delta-sigma modulator, a demodulator, a second-order tracking loop, a first oscillator and a second oscillator; The output end of the adaptive zero-delta-sigma modulator is connected to the input end of the demodulator, and is used to send an output signal to the demodulator according to the input resolver sine signal and resolver cosine signal; The output end of the demodulator is connected to the input end of the second-order tracking loop and the input end of the adaptive zero-delta-sigma modulator, and is used to output an angle error value to the second-order tracking loop and the adaptive zero-delta-sigma modulator according to the connected output signal, sine output angle, cosine output angle and sine excitation angle, wherein the angle error value is the angle value of the input shaft angle minus the output angle; The output end of the second-order tracking loop is connected to the input end of the second oscillator and the input end of the adaptive zero-delta-sigma modulator, and is used to send the output angle to the second oscillator and the adaptive zero-delta-sigma modulator according to the angle error value connected; The output end of the second oscillator is connected to the input end of the demodulator, and is used to output the sine output angle and the cosine output angle to the demodulator according to the output angle; The output end of the first oscillator is connected to the input end of the demodulator, and is used to output a sinusoidal excitation angle to the demodulator according to the input excitation parameters; The adaptive zero-point incremental-sigma modulator is also used to perform zero-point tracking on the resolver sine signal and the resolver cosine signal according to the output angle and the excitation parameter when it is determined that there is a need for zero-point adjustment based on the angle error value, so as to reduce the noise component on the resolver sine signal and the resolver cosine signal.

2. A signal-to-noise ratio adjustment method, characterized in that: The signal-to-noise ratio adjustment method is applied to the signal-to-noise ratio adjustment device according to claim 1, characterized in that the signal-to-noise ratio adjustment method comprises: Through an adaptive zero-point incremental-sigma modulator, zero-point tracking is performed on a resolver sine signal and a resolver cosine signal, and a zero point is set at a target frequency of the resolver sine signal and a target frequency of the resolver cosine signal to reduce noise components on the resolver sine signal and the resolver cosine signal.

3. The signal-to-noise ratio adjustment method according to claim 2, characterized in that: Before the step of performing zero point tracking on the resolver sine signal and the resolver cosine signal, the method includes: Calculating the angle error value between the input shaft angle and the output angle through the adaptive zero-delta-sigma modulator, and determining whether the angle error value is less than a preset error threshold; If it is determined that the angle error value is less than the preset error threshold, controlling the adaptive zero-delta-sigma modulator to start a zero-point tracking function; If it is determined that the angle error value is greater than the preset error threshold, the adaptive zero-delta-sigma modulator is controlled to turn off the zero-point tracking function.

4. The signal-to-noise ratio adjustment method according to claim 3, characterized in that: When the zero point tracking function is turned on, the zero point forms a correlation with the signal frequency and the output angle.

5. The signal-to-noise ratio adjustment method according to claim 2, characterized in that: In the case where the delta-sigma modulator included in the adaptive zero-point delta-sigma modulator is a third-order delta-sigma modulator, the zero point includes a first zero point, a second zero point, and a third zero point, and the step of setting the zero point at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal includes: The first zero point is set at the DC frequency of the resolver sine signal and the DC frequency of the resolver cosine signal, the second zero point is set at the positive signal frequency of the resolver sine signal and the positive signal frequency of the resolver cosine signal, and the third zero point is set at the negative signal frequency of the resolver sine signal and the negative signal frequency of the resolver cosine signal; The DC frequency, the positive signal frequency and the negative signal frequency are the target frequencies.

6. The signal-to-noise ratio adjustment method according to claim 5, characterized in that: In the case where the delta-sigma modulator is a fifth-order delta-sigma modulator, the zero points include a first zero point, a second zero point, a third zero point, a fourth zero point, and a fifth zero point, and the step of setting the zero points at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal includes: The first zero point is set at the DC frequency of the resolver sine signal and the DC frequency of the resolver cosine signal, the second zero point is set at the first positive frequency of the resolver sine signal and the first positive frequency of the resolver cosine signal, the third zero point is set at the second positive frequency of the resolver sine signal and the second positive frequency of the resolver cosine signal, the fourth zero point is set at the first negative frequency of the resolver sine signal and the first negative frequency of the resolver cosine signal, and the fifth zero point is set at the second negative frequency of the resolver sine signal and the second negative frequency of the resolver cosine signal; The DC frequency, the first positive frequency, the second positive frequency, the first negative frequency and the second negative frequency are the target frequencies.

7. The signal-to-noise ratio adjustment method according to claim 6, characterized in that: The first positive frequency is the sum of the excitation frequency and the rotation frequency in the positive direction of the horizontal axis, and the second positive frequency is the difference between the excitation frequency and the rotation frequency in the positive direction of the horizontal axis; The first negative frequency is the sum of the excitation frequency and the rotation frequency in the negative direction of the horizontal axis, and the second negative frequency is the difference between the excitation frequency and the rotation frequency in the negative direction of the horizontal axis.

8. The signal-to-noise ratio adjustment method according to claim 2, characterized in that: After the step of setting the zero point at the target frequency of the resolver sine signal and the target frequency of the resolver cosine signal, the method further includes: Obtaining a sine output signal and a cosine output signal, and inputting the sine output signal into a first multiplier to multiply it with the cosine signal to obtain a first signal to be output, and inputting the cosine output signal into a second multiplier to multiply it with the sine signal to obtain a second signal to be output; The first signal to be output and the second signal to be output are input into a first adder for subtraction to obtain an excitation signal, and then the excitation signal is input into a third multiplier to be multiplied with the modulation signal to output a demodulated signal.

9. A signal-to-noise ratio adjustment system, characterized in that: The signal-to-noise ratio adjustment system comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the signal-to-noise ratio adjustment method according to any one of claims 2 to 8.

10. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the signal-to-noise ratio adjustment method according to any one of claims 2 to 8 are implemented.

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