Inverse Locked Amplifier, Household Appliance, and Phase Information Acquisition Method

Abstract

The present invention discloses an inverse lock-in amplifier, which is used to process a signal to be measured including a fundamental frequency part, a third harmonic part and a noise part. The inverse lock-in amplifier includes a phase-sensitive detector and a high-pass filter connected to the phase-sensitive detector. The phase-sensitive detector is used to receive the signal to be measured and a reference signal and filter out the noise part according to the signal to be measured and the reference signal to obtain an effective signal, and the effective signal includes a first signal corresponding to the fundamental frequency part and a second signal corresponding to the third harmonic part. The high-pass filter is used to filter out the first signal to obtain the second signal. In addition, the present invention also discloses a household appliance and a phase information acquisition method. After the phase-sensitive detector of the inverse lock-in amplifier, household appliance and phase information acquisition method of the present invention outputs an effective signal, the high-pass filter is used to filter out the first signal in the effective signal to obtain the second signal corresponding to the third harmonic part, so that the phase information of the signal to be measured included in the third harmonic part can be obtained.

Description

Technical Field

[0001] The present invention relates to the field of sensor signal processing, and particularly to an inverse lock-in amplifier, a household appliance, and a method for obtaining phase information. Background Art

[0002] In the related art, generally, a lock-in amplifier is used to reduce or remove the noise signal in the output signal of a micro-resonant sensor to extract the effective signal in the output signal. However, due to the function of the low-pass filter in the lock-in amplifier, the triple-frequency part with phase information in the output signal will be filtered out, making it difficult to obtain the phase information of the output signal. Summary of the Invention

[0003] Embodiments of the present invention provide an inverse lock-in amplifier, a household appliance, and a method for obtaining phase information.

[0004] An inverse lock-in amplifier according to an embodiment of the present invention is used to process a signal to be measured, where the signal to be measured includes a fundamental frequency part, a triple-frequency part, and a noise part. The inverse lock-in amplifier includes:

[0005] A phase-sensitive detector for receiving the signal to be measured and a reference signal and filtering out the noise part of the signal to be measured according to the signal to be measured and the reference signal to obtain an effective signal, where the effective signal includes a first signal corresponding to the fundamental frequency part and a second signal corresponding to the triple-frequency part; and

[0006] A high-pass filter connected to the phase-sensitive detector for filtering out the first signal to obtain the second signal.

[0007] In some embodiments, the phase-sensitive detector includes an input terminal for the signal to be measured, an input terminal for the reference signal, and an output terminal for the effective signal. The high-pass filter includes an input terminal for the effective signal and an output terminal of the filter. The input terminal for the signal to be measured is used to receive the signal to be measured, the input terminal for the reference signal is used to receive the reference signal, the output terminal for the effective signal is connected to the input terminal for the effective signal and is used to output the effective signal to the input terminal for the effective signal, and the output terminal of the filter is used to output the second signal.

[0008] In some embodiments, the high-pass filter includes an input terminal for an adjustment channel, and the high-pass filter is used to adjust the cut-off frequency of the high-pass filter according to an adjustment signal received by the input terminal for the adjustment channel.

[0009] In some embodiments, the input terminal for the adjustment channel is used to receive the reference signal as the adjustment signal, and the high-pass filter is used to adjust the cut-off frequency of the high-pass filter according to the frequency of the reference signal.

[0010] In some embodiments, the input end of the adjustment channel is used to receive a control voltage as the adjustment signal, and the high-pass filter is used to adjust the cut-off frequency of the high-pass filter according to the voltage value of the control voltage.

[0011] In some embodiments, the inverse phase-locked amplifier includes an amplification and shaping circuit and a frequency division circuit. The amplification and shaping circuit is used to amplify and shape the second signal, and the frequency division circuit is used to divide the frequency of the amplified and shaped second signal to obtain a phase signal.

[0012] In some embodiments, the phase-sensitive detector is used to convert the fundamental frequency part into a second harmonic part and use it as the first signal, and to convert the third harmonic part into a fourth harmonic part and use it as the second signal, and to convert the noise part into a DC component;

[0013] The high-pass filter is used to filter out the second harmonic part and the DC component to obtain the fourth harmonic part;

[0014] The amplification and shaping circuit is used to amplify and shape the fourth harmonic part, and the frequency division circuit is used to divide the frequency of the amplified and shaped fourth harmonic part to obtain the phase signal.

[0015] In some embodiments, the inverse phase-locked amplifier includes a signal channel and a reference channel. The signal channel is used to collect a first input signal and process the first input signal to obtain the signal to be measured, and the reference channel is used to collect a second input signal and process the second input signal to obtain the reference signal.

[0016] In some embodiments, the frequency division circuit is connected to the signal channel and the reference channel. The signal channel is used to process the first input signal according to the phase signal to obtain the signal to be measured, and the reference channel is used to process the second input signal according to the phase signal to obtain the reference signal.

[0017] An appliance according to an embodiment of the present invention includes a micro-resonant sensor and the inverse phase-locked amplifier, and the resonant sensor is used to output the signal to be measured to the inverse phase-locked amplifier.

[0018] A method for obtaining phase information according to an embodiment of the present invention uses the inverse phase-locked amplifier to process a signal to be measured. The signal to be measured includes a fundamental frequency part, a third harmonic part, and a noise part. The method for obtaining phase information includes:

[0019] The phase-sensitive detector receives the signal to be measured and the reference signal and filters out the noise part of the signal to be measured according to the signal to be measured and the reference signal to obtain an effective signal, where the effective signal includes a first signal corresponding to the fundamental frequency part and a second signal corresponding to the third harmonic part; and

[0020] The high-pass filter filters out the first signal to obtain the second signal.

[0021] After the inverse lock-in amplifier, the household appliance, and the phase information acquisition method according to the embodiments of the present invention output an effective signal through the phase-sensitive detector, the high-pass filter is used to filter out the first signal in the effective signal to obtain the second signal corresponding to the third harmonic part, so that the phase information of the signal to be measured included in the third harmonic part can be obtained.

[0022] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. Description of the Drawings

[0023] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, where:

[0024] Figure 1 is a schematic block diagram of an inverse lock-in amplifier according to an embodiment of the present invention;

[0025] Figure 2 is another schematic block diagram of an inverse lock-in amplifier according to an embodiment of the present invention;

[0026] Figure 3 is still another schematic block diagram of an inverse lock-in amplifier according to an embodiment of the present invention;

[0027] Figure 4 is yet another schematic block diagram of an inverse lock-in amplifier according to an embodiment of the present invention;

[0028] Figure 5 is yet another schematic block diagram of an inverse lock-in amplifier according to an embodiment of the present invention;

[0029] Figure 6 is a schematic flow chart of a phase information acquisition method according to an embodiment of the present invention;

[0030] Figure 7 is a schematic block diagram of a household appliance according to an embodiment of the present invention;

[0031] Figure 8 is another schematic flow chart of a phase information acquisition method according to an embodiment of the present invention;

[0032] Figure 9It is yet another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention;

[0033] Figure 10 It is another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention;

[0034] Figure 11 It is another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention;

[0035] Figure 12 It is another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention;

[0036] Figure 13 It is another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention;

[0037] Figure 14 It is another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention;

[0038] Figure 15 It is another flowchart diagram of the phase information acquisition method according to an embodiment of the present invention.

[0039] Main element symbol description:

[0040] Household appliance 1000, micro-resonant sensor 100, inverse phase-locked amplifier 200, phase-sensitive detector 210, signal input terminal to be measured 212, reference signal input terminal 214, effective signal output terminal 216, high-pass filter 220, effective signal input terminal 222, filter output terminal 224, adjustment channel input terminal 226, amplification and shaping circuit 230, frequency division circuit 240, signal channel 250, reference channel 260. Specific embodiments

[0041] The following details the embodiments of the present invention. The embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

[0042] Please refer to Figures 1-5, the inverse lock-in amplifier 200 according to the embodiment of the present invention can be used to process a signal to be measured. The signal to be measured includes a fundamental frequency part, a third harmonic part, and a noise part. The inverse lock-in amplifier 200 includes a phase-sensitive detector 210 and a high-pass filter 220 connected to the phase-sensitive detector 210. The phase-sensitive detector 210 is configured to receive the signal to be measured and a reference signal and filter out the noise part of the signal to be measured according to the signal to be measured and the reference signal to obtain an effective signal. The effective signal includes a first signal corresponding to the fundamental frequency part and a second signal corresponding to the third harmonic part. The high-pass filter 220 is configured to filter out the first signal to obtain the second signal.

[0043] Please refer to Figure 6 , for the phase information acquisition method according to the embodiment of the present invention, the inverse lock-in amplifier 200 is used to process the signal to be measured. The signal to be measured includes a fundamental frequency part, a third harmonic part, and a noise part. The phase information acquisition method includes:

[0044] Step S210: The phase-sensitive detector 210 receives the signal to be measured and the reference signal and filters out the noise part of the signal to be measured according to the signal to be measured and the reference signal to obtain an effective signal. The effective signal includes a first signal corresponding to the fundamental frequency part and a second signal corresponding to the third harmonic part; and

[0045] Step S220: The high-pass filter 220 filters out the first signal to obtain the second signal.

[0046] The phase information acquisition method according to the embodiment of the present invention can be implemented by the inverse lock-in amplifier 200 according to the embodiment of the present invention. Among them, step S210 can be implemented by the phase-sensitive detector 210, and step S220 can be implemented by the high-pass filter 220.

[0047] Please refer to Figure 7 , the household appliance 1000 according to the embodiment of the present invention includes a micro-resonant sensor 100 and the inverse lock-in amplifier 200 according to the embodiment of the present invention. The micro-resonant sensor 100 is configured to output the signal to be measured to the inverse lock-in amplifier 200.

[0048] After the inverse lock-in amplifier 200, the household appliance 1000, and the phase information acquisition method according to the embodiment of the present invention output an effective signal by the phase-sensitive detector 210, the high-pass filter 220 is used to filter out the first signal in the effective signal to obtain the second signal corresponding to the third harmonic part, so that the phase information of the signal to be measured included in the third harmonic part can be obtained.

[0049] In the embodiment of the present invention, the micro-resonant sensor 100 and the inverse lock-in amplifier 200 are separately arranged and connected to each other. It can be understood that in other embodiments, the micro-resonant sensor 100 may include the inverse lock-in amplifier 200, that is, the inverse lock-in amplifier 200 is arranged in the micro-resonant sensor 100.

[0050] In some embodiments, the micro-resonant sensor 100 can be used for gas detection. For example, the household appliance 100 can be a range hood. In some embodiments, the micro-resonant sensor 100 can be used for acceleration detection. For example, the household appliance 100 can be a floor cleaning robot. No specific limitation is made herein.

[0051] In some embodiments, the signal to be measured can refer to the output signal of the micro-resonant sensor. The micro-resonant sensor refers to a resonant sensor with a size in the micron or nanometer range. The fundamental frequency part of the signal to be measured can refer to the fundamental frequency of resonance. The third harmonic part of the signal to be measured generally includes the phase information of the signal to be measured. The noise part of the signal to be measured can refer to the thermal noise generated by the ambient temperature.

[0052] In some embodiments, the phase-sensitive detector 210 can refer to a high-frequency multiplier. The signal to be measured can be expressed as: wherein Asin(ω0t) is the fundamental frequency part, Bsin(3ω0t) is the third harmonic part, and n(t) is the noise part. The reference signal can be expressed as: y(t) = V r sin(ω0t).

[0053] In some embodiments, the high-frequency filter is also called a low-cut filter or a low-impedance filter, which allows signals above the cut-off frequency to pass through and greatly attenuates signals below the cut-off frequency.

[0054] Please refer to Figures 1-5 , in some embodiments, the phase-sensitive detector 210 includes a signal-to-be-measured input terminal 212, a reference signal input terminal 214, and an effective signal output terminal 216. The high-pass filter 220 includes an effective signal input terminal 222 and a filter output terminal 224. The signal-to-be-measured input terminal 212 is used to receive the signal to be measured. The reference signal input terminal 214 is used to receive the reference signal. The effective signal output terminal 216 is connected to the effective signal input terminal 222 and is used to output the effective signal to the effective signal input terminal 222. The filter output terminal 224 is used to output the second signal.

[0055] Please refer to Figure 8 , in some embodiments, the phase-sensitive detector 210 includes a signal-to-be-measured input terminal 212, a reference signal input terminal 214, and an effective signal output terminal 216. The high-pass filter 220 includes an effective signal input terminal 222 and a filter output terminal 224. The effective signal output terminal 216 is connected to the effective signal input terminal 222. Step S210 includes:

[0056] Step S212: The signal-to-be-measured input terminal 212 receives the signal to be measured;

[0057] Step S214: The reference signal input terminal 214 receives the reference signal;

[0058] Step S216: The valid signal output terminal 216 outputs a valid signal to the valid signal input terminal 222;

[0059] Step S220 includes:

[0060] Step S224: The filter output terminal 224 outputs a second signal.

[0061] That is to say, step S212 can be implemented by the signal under test input terminal 212, step S214 can be implemented by the reference signal input terminal 214, step S216 can be implemented by the valid signal output terminal 216 and the valid signal input terminal 222, and step S224 can be implemented by the filter output terminal 224.

[0062] In this way, the phase-sensitive detector 210 can output the valid signal to the valid signal input terminal 222 of the high-pass filter 220 through the valid signal output terminal 216.

[0063] Specifically, the phase-sensitive detector 210 generally includes two input terminals, the signal under test input terminal 212 and the reference signal input terminal 214. Through these two input terminals, the phase-sensitive detector 210 can receive the signal under test and the reference signal. After being processed by the phase-sensitive detector 210, the valid signal is obtained. The valid signal can be output from the valid signal output terminal 216 of the phase-sensitive detector 210 to the valid signal input terminal 222 of the high-pass filter 220. After the valid signal passes through the filtering function of the high-pass filter 220 (signals with frequencies higher than the cut-off frequency can pass through, and signals with frequencies lower than the cut-off frequency are filtered out), the second signal in the valid signal is retained and output through the filter output terminal 224.

[0064] Please refer to Figures 2-5 , in some embodiments, the high-pass filter 220 includes an adjustment channel input terminal 226, and the high-pass filter 220 is used to adjust the cut-off frequency of the high-pass filter 220 according to the adjustment signal received by the adjustment channel input terminal 226.

[0065] Please refer to Figure 9 , in some embodiments, the high-pass filter 220 includes an adjustment channel input terminal 226, and step S220 includes:

[0066] Step S226: The high-pass filter 220 adjusts the cut-off frequency of the high-pass filter 220 according to the adjustment signal received by the adjustment channel input terminal 226.

[0067] That is to say, step S226 can be implemented by the high-pass filter 220.

[0068] In this way, the cut-off frequency of the high-pass filter 220 can be adjusted.

[0069] Specifically, since the frequency of the valid signal may be within a relatively wide range, in different scenarios, the cut-off frequency of the high-pass filter 220 required by the inverse phase-locked amplifier 200 may be different. If the cut-off frequency of the high-pass filter 220 is designed as a fixed frequency, it may be necessary to determine the optimal value of the fixed frequency through a large number of experiments or use multiple high-pass filters 220 to adapt to different scenarios, which may increase additional costs or reduce the manufacturing efficiency of the inverse phase-locked amplifier 220. In some embodiments, the high-pass filter 220 may be designed as a voltage-controlled high-pass or a tracking high-pass. The high-pass filter 220 includes an adjustment channel input terminal 226, and the cut-off frequency of the high-pass filter 220 can be adjusted according to the adjustment signal received by the adjustment channel input terminal 226.

[0070] Please refer to Figures 2-5 , in some embodiments, the adjustment channel input terminal 226 is used to receive a reference signal as the adjustment signal, and the high-pass filter 220 is used to adjust the cut-off frequency of the high-pass filter 220 according to the frequency of the reference signal.

[0071] Please refer to Figure 10 , in some embodiments, step S226 includes:

[0072] Step S2262: The adjustment channel input terminal 226 receives a reference signal as the adjustment signal;

[0073] Step S2264: The high-pass filter 220 adjusts the cut-off frequency of the high-pass filter 220 according to the frequency of the reference signal.

[0074] That is to say, step S2262 can be implemented by the adjustment channel input terminal 226, and step S2264 can be implemented by the high-pass filter 220.

[0075] In this way, the high-pass filter 220 can be designed as a tracking high-pass, and the cut-off frequency of the high-pass filter 220 can be adjusted according to the frequency of the reference signal.

[0076] In some embodiments, the frequency of the reference signal is outside the frequency range that the adjustment channel input terminal 226 can receive. Therefore, before the reference signal is input to the high-pass filter 220, the frequency of the reference signal can be adjusted first. For example, the frequency of the reference signal is adjusted to a first predetermined multiple of the original frequency, such as 50 times, and then input to the high-pass filter 220 through the adjustment channel input terminal 226. After receiving the reference signal, the high-pass filter 220 can multiply the frequency of the adjusted reference signal by a second predetermined multiple to obtain the cut-off frequency of the high-pass filter 220. The second predetermined multiple can be, for example, 100 times. Thus, the high-pass filter 220 can adjust its own cut-off frequency according to the frequency of the reference signal.

[0077] Please refer to Figures 2-5 , in some embodiments, the adjustment channel input terminal 226 is used to receive a control voltage as an adjustment signal, and the high-pass filter 220 is used to adjust the cut-off frequency of the high-pass filter 220 according to the voltage value of the control voltage.

[0078] Please refer to Figure 11 , in some embodiments, step S226 includes:

[0079] Step S2266: The adjustment channel input terminal 226 receives a control voltage as an adjustment signal;

[0080] Step S2268: The high-pass filter 220 adjusts the cut-off frequency of the high-pass filter 220 according to the voltage value of the control voltage.

[0081] That is to say, step S2266 can be implemented by the adjustment channel input terminal 226, and step S2268 can be implemented by the high-pass filter 220.

[0082] In this way, the high-pass filter 220 can be designed as a voltage-controlled high-pass filter, and the cut-off frequency of the high-pass filter 220 can be adjusted according to the voltage value of the control voltage.

[0083] In some embodiments, a control voltage can be directly input to the adjustment channel input terminal 226, so that the high-pass filter 220 can quickly adjust the cut-off frequency of the high-pass filter 220 according to the voltage value of the control voltage. The cut-off frequency of the high-pass filter 220 can be positively or negatively correlated with the voltage value of the control voltage, which is not specifically limited herein. In one embodiment, the cut-off frequency of the high-pass filter 220 is positively correlated with the voltage value of the control voltage. For example, when the voltage value of the input control voltage is 3V, the cut-off frequency of the high-pass filter 220 is 5kHz, and when the voltage value of the input control voltage is 5V, the cut-off frequency of the high-pass filter 220 is 10kHz.

[0084] Please refer to Figures 3-5 , in some embodiments, the inverse phase-locked amplifier 200 includes an amplification and shaping circuit 230 and a frequency division circuit 240. The amplification and shaping circuit 230 is used to amplify and shape the second signal, and the frequency division circuit 240 is used to divide the frequency of the amplified and shaped second signal to obtain a phase signal.

[0085] Please refer to Figure 12 , in some embodiments, the inverse phase-locked amplifier 200 includes an amplification and shaping circuit 230 and a frequency division circuit 240. The phase information acquisition method includes:

[0086] Step S230: The amplification and shaping circuit 230 amplifies and shapes the second signal;

[0087] Step S240: The frequency division circuit 240 divides the second signal that has been amplified and shaped to obtain a phase signal.

[0088] That is to say, step S230 can be implemented by the amplification and shaping circuit 230, and step S240 can be implemented by the frequency division circuit 240.

[0089] In this way, the second signal can be processed to obtain a phase signal.

[0090] Specifically, since the signal that can be obtained by the micro-resonant sensor 100 is very small, after the second signal is obtained, the amplification and shaping circuit 230 can amplify the second signal to increase the amplitude of the second signal. In addition, the amplification and shaping circuit 230 also shapes the second signal in the form of a sine wave into a square wave to facilitate the frequency division by the frequency division circuit 240 and improve the accuracy of the phase information of the phase signal after frequency division.

[0091] Please refer to Figures 3-5 , in some embodiments, the phase-sensitive detector 210 is used to convert the fundamental frequency part into a second harmonic part and use it as the first signal, and to convert the third harmonic part into a fourth harmonic part and use it as the second signal, and to convert the noise part into a DC component;

[0092] The high-pass filter 220 is used to filter out the second harmonic part and the DC component to obtain the fourth harmonic part;

[0093] The amplification and shaping circuit 230 is used to amplify and shape the fourth harmonic part, and the frequency division circuit 240 is used to divide the amplified and shaped fourth harmonic part to obtain a phase signal.

[0094] Please refer to Figure 13 , in some embodiments, step S210 includes:

[0095] Step S218: The phase-sensitive detector 210 converts the fundamental frequency part into a second harmonic part and uses it as the first signal, and converts the third harmonic part into a fourth harmonic part and uses it as the second signal, and converts the noise part into a DC component;

[0096] Step S220 includes:

[0097] Step S228: The high-pass filter 220 filters out the second harmonic part and the DC component to obtain the fourth harmonic part;

[0098] Step S230 includes:

[0099] Step S232: The amplification and shaping circuit 230 amplifies and shapes the fourth harmonic part;

[0100] Step S240 includes:

[0101] Step S242: The frequency division circuit 240 divides the quadrupled frequency part after amplification and shaping to obtain a phase signal.

[0102] That is to say, step S218 can be implemented by the phase sensitive detector 210, step S228 can be implemented by the high-pass filter 220, step S232 can be implemented by the amplification and shaping circuit 230, and step S242 can be implemented by the frequency division circuit 240.

[0103] In this way, the signal to be measured and the reference signal can be processed to obtain a phase signal.

[0104] Specifically, the signal to be measured and the reference signal y(t) = V r sin(ω0t), after passing through the phase sensitive detector 210, the phase sensitive detector 210 converts the fundamental frequency part into a doubled frequency part and uses it as the first signal, converts the triple frequency part into a quadrupled frequency part and uses it as the second signal, and converts the noise part into a DC component. The effective signal output by the phase sensitive detector 210 is where A'sin(2ω0t) is the doubled frequency part converted from the fundamental frequency part, that is, the first signal, is the quadrupled frequency part converted from the triple frequency part, that is, the second signal, and Z is the DC component converted from the noise part. The doubled frequency part and the DC component in the effective signal are filtered out in the high-pass filter 220, while the quadrupled frequency part is retained. After the gain of the high-pass filter 220, the second signal output by the high-pass filter 220 is where C is the gain multiple of the high-pass filter 220.

[0105] The second signal output by the high-pass filter 220 is amplified and shaped by the amplification and shaping circuit 230. After amplification and shaping, the second signal can be frequency-divided by the frequency division circuit 240. Among them, since the second signal is a quadrupled frequency signal, the frequency division circuit 240 can be a quarter-frequency division circuit, so that the second signal can be frequency-divided to obtain a phase signal with a frequency of the fundamental frequency, and this phase signal characterizes the phase information of the signal to be measured.

[0106] Please refer to Figure 4 and 5 , in some embodiments, the inverse lock-in amplifier 200 includes a signal channel 250 and a reference channel 260. The signal channel 250 is used to collect the first input signal and process the first input signal to obtain the signal to be measured, and the reference channel 260 is used to collect the second input signal and process the second input signal to obtain the reference signal.

[0107] Please refer to Figure 14 , in some embodiments, the inverse lock-in amplifier 200 includes a signal channel 250 and a reference channel 260. The phase information acquisition method includes:

[0108] Step S250: The signal channel 250 collects the first input signal and processes the first input signal to obtain a signal to be measured;

[0109] Step S260: The reference channel 260 collects the second input signal and processes the second input signal to obtain a reference signal.

[0110] That is to say, step S250 can be implemented by the signal channel 250, and step S260 can be implemented by the reference channel 260.

[0111] In this way, the signal to be measured and the reference signal can be made applicable to the phase-sensitive detector 210.

[0112] Specifically, the phase-sensitive detector 210 may have certain requirements for the input signal to be measured and the reference signal. For example, the amplitude of the signal to be measured is the third predetermined multiple of the amplitude of the reference signal, and the third predetermined multiple is, for example, 3 times. Therefore, it is necessary to preprocess the first input signal and the second input signal through the signal channel 250 and the reference channel 260, such as shaping and amplitude modulation of the first input signal and the second input signal, so that the signal to be measured and the reference signal meet the requirements of the phase-sensitive detector 210. In some embodiments, the first input signal is the output signal of the micro-resonant sensor 100. The first input signal is essentially also the signal to be measured, but is input into the phase-sensitive detector 210 after being processed by the signal channel.

[0113] Please refer to Figure 5 , in some embodiments, the frequency division circuit 240 is connected to the signal channel 250 and the reference channel 260. The signal channel 250 is used to process the first input signal according to the phase signal to obtain a signal to be measured, and the reference channel 260 is used to process the second input signal according to the phase signal to obtain a reference signal.

[0114] Please refer to Figure 15 , in some embodiments, the frequency division circuit 240 is connected to the signal channel 250 and the reference channel 260. Step S250 includes:

[0115] Step S252: The signal channel 250 processes the first input signal according to the phase signal to obtain a signal to be measured;

[0116] Step S260 includes:

[0117] Step S262: The reference channel 260 processes the second input signal according to the phase signal to obtain a reference signal.

[0118] That is to say, step S252 can be implemented by the signal channel 250, and step S262 can be implemented by the reference channel 260.

[0119] In this way, the first input signal and the second input signal can be processed according to the phase signal to achieve closed-loop control.

[0120] In some embodiments, the phase signal output by the frequency division circuit 240 is transmitted to the signal channel 250 and the reference channel 260 after passing through a phase-locked loop (not shown in the figure). The signal channel 250 can adjust the amplitude of the first input signal according to the amplitude of the phase signal to obtain the signal to be measured, and the reference channel 260 can adjust the amplitude of the second input signal according to the amplitude of the phase signal to obtain the reference signal. In one embodiment, the signal channel 250 adjusts the amplitude of the first input signal to 15 times the amplitude of the phase signal as the signal to be measured, and the reference channel 260 adjusts the amplitude of the second input signal to 5 times the amplitude of the phase signal as the reference signal.

[0121] In the description of the embodiments of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the embodiments of the present invention, the meaning of "a plurality" is two or more unless otherwise specifically defined.

[0122] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "mounted", "connected" and "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, an electrical connection or a communication with each other; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0123] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0124] Any process or method description represented in a flowchart or otherwise described herein can be understood to represent a module, segment, or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present invention includes additional implementations, where functions may be executed in a substantially simultaneous manner or in a reverse order according to the functions involved, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0125] The logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing a logical function, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processing module, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion having one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, a computer-readable medium can even be paper or other suitable media on which the program can be printed, as the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0126] It should be understood that various parts of the embodiments of the present invention can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented using hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0127] Those of ordinary skill in the art can understand that all or part of the steps carried out in implementing the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0128] In addition, in each of the embodiments of the present invention, the functional units can be integrated into a processing module, or each unit can exist physically alone, or two or more units can be integrated into one module. The above integrated module can be implemented in the form of hardware or in the form of a software functional module. When the above integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0129] The above-mentioned storage medium can be a read-only memory, a magnetic disk, an optical disc, etc.

[0130] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. An inverse lock-in amplifier for processing a signal to be measured, the signal to be measured including a fundamental frequency part, a third harmonic part, and a noise part, characterized in that, The inverse lock-in amplifier includes: A phase-sensitive detector, which is configured to receive the signal to be measured and a reference signal and filter out the noise part of the signal to be measured according to the signal to be measured and the reference signal to obtain an effective signal, where the effective signal includes a first signal corresponding to the fundamental frequency part and a second signal corresponding to the third harmonic part; and A high-pass filter connected to the phase-sensitive detector, which is configured to filter out the first signal to obtain the second signal; The inverse lock-in amplifier includes an amplification and shaping circuit and a frequency division circuit. The amplification and shaping circuit is configured to amplify and shape the second signal, and the frequency division circuit is configured to divide the amplified and shaped second signal to obtain a phase signal; The phase-sensitive detector is configured to convert the fundamental frequency part into a second harmonic part and use it as the first signal, convert the third harmonic part into a fourth harmonic part and use it as the second signal, and convert the noise part into a DC component; The high-pass filter is configured to filter out the second harmonic part and the DC component to obtain the fourth harmonic part; The amplification and shaping circuit is configured to amplify and shape the fourth harmonic part, and the frequency division circuit is configured to divide the amplified and shaped fourth harmonic part to obtain the phase signal.

2. The inverse lock-in amplifier according to claim 1, characterized in that, The phase-sensitive detector includes an input terminal for the signal to be measured, an input terminal for the reference signal, and an output terminal for the effective signal. The high-pass filter includes an input terminal for the effective signal and an output terminal of the filter. The input terminal for the signal to be measured is configured to receive the signal to be measured, the input terminal for the reference signal is configured to receive the reference signal, the output terminal for the effective signal is connected to the input terminal for the effective signal and is configured to output the effective signal to the input terminal for the effective signal, and the output terminal of the filter is configured to output the second signal.

3. The inverse lock-in amplifier according to claim 1, characterized in that, The high-pass filter includes an input terminal for the adjustment channel, and the high-pass filter is configured to adjust the cut-off frequency of the high-pass filter according to an adjustment signal received by the input terminal for the adjustment channel.

4. The inverse lock-in amplifier according to claim 3, characterized in that, The input terminal for the adjustment channel is configured to receive the reference signal as the adjustment signal, and the high-pass filter is configured to adjust the cut-off frequency of the high-pass filter according to the frequency of the reference signal.

5. The inverse lock-in amplifier according to claim 3, characterized in that, The input terminal for the adjustment channel is configured to receive a control voltage as the adjustment signal, and the high-pass filter is configured to adjust the cut-off frequency of the high-pass filter according to the voltage value of the control voltage.

6. The inverse lock-in amplifier according to claim 1, characterized in that, The inverse lock-in amplifier includes a signal channel and a reference channel. The signal channel is configured to collect a first input signal and process the first input signal to obtain the signal to be measured, and the reference channel is configured to collect a second input signal and process the second input signal to obtain the reference signal.

7. The inverse lock-in amplifier according to claim 6, characterized in that, The frequency division circuit is connected to the signal channel and the reference channel. The signal channel is configured to process the first input signal according to the phase signal to obtain the signal to be measured, and the reference channel is configured to process the second input signal according to the phase signal to obtain the reference signal.

8. A household appliance, characterized in that, Comprising a micro-resonant sensor and the inverse lock-in amplifier according to any one of claims 1-7, the micro-resonant sensor being configured to output the signal to be measured to the inverse lock-in amplifier.

9. A method for obtaining phase information, using the inverse lock-in amplifier according to any one of claims 1-7 to process a signal to be measured, the signal to be measured including a fundamental frequency part, a third harmonic part, and a noise part, characterized in that, The method for obtaining the phase information includes: The phase-sensitive detector receives the signal to be measured and the reference signal and filters out the noise portion of the signal to be measured based on the signal to be measured and the reference signal to obtain an effective signal, the effective signal including a first signal corresponding to the fundamental frequency portion and a second signal corresponding to the third harmonic frequency portion; and The high-pass filter filters out the first signal to obtain the second signal.

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