Phase adjusting circuit and method and distance measuring device

Abstract

The invention relates to a phase adjusting circuit and method and a distance measuring device. The phase adjustment circuit comprises: at least one adjustment unit configured to adjust an input signal according to an initial gain coefficient to generate an adjustment signal; and changing a gain coefficient for adjusting the input signal in response to a gate control signal; wherein when the adjusting unit has different gain coefficients, the cut-off frequencies corresponding to the gain coefficients are the same; and the control unit is coupled with the adjusting unit and is configured to generate the gating control signal to the adjusting unit according to the adjusting signal and a preset signal. By adopting the scheme, the phase delay in the dynamic range can be reduced, and the distance measurement precision is improved.

Description

Technical Field

[0001] This application relates to the field of sensor technology, and in particular to a phase adjustment circuit and method, and a ranging device. Background Technology

[0002] Laser rangefinders typically use indirect time-of-flight (ITOF) technology to achieve ranging functionality. The principle of a laser rangefinder is that a laser emits a periodically modulated light signal, which strikes the target and returns. A silicon photodiode (PIN) or avalanche photodiode (APD) then converts the modulated light signal into an electrical signal. The distance between the sensor and the target is calculated by measuring the phase difference between the transmitted and received signals.

[0003] Ranging range is a key performance indicator for laser ranging sensors. In practical applications, laser ranging sensors are generally required to have as small a blind zone as possible at close range and as long a ranging range as possible at long range. Correspondingly, for the hardware system, dynamic range is a key design indicator for laser ranging sensors. That is, at close range, the sensor should avoid nonlinear phase errors caused by saturation due to a strong light signal; while at long range, it should avoid phase errors caused by a low signal-to-noise ratio due to a weak light signal, which would lead to ranging errors.

[0004] During different ranging processes, a switching operation is usually required to adjust the optical signal and achieve dynamic range ranging. However, performing dynamic range adjustment introduces different phase delays, which in turn leads to ranging errors. Summary of the Invention

[0005] Therefore, it is necessary to provide a phase adjustment circuit and method, and a ranging device that can reduce phase delay in the dynamic range and improve ranging accuracy, in order to address the above-mentioned technical problems.

[0006] In a first aspect, this application provides a phase adjustment circuit. The phase adjustment circuit includes:

[0007] At least one adjustment unit is configured to adjust an input signal according to an initial gain coefficient to generate an adjusted signal; and to change a gain coefficient for adjusting the input signal in response to a gating control signal; wherein, when the adjustment units have different gain coefficients, the cutoff frequency corresponding to each gain coefficient is the same;

[0008] The control unit, coupled to the adjustment unit, is configured to generate the gating control signal to the adjustment unit based on the adjustment signal and a preset signal.

[0009] In one embodiment, at least one of the adjustment units includes a plurality of adjustment units, any two of the adjustment units having different gain coefficients, but any two of the adjustment units having the same cutoff frequency.

[0010] In one embodiment, each of the adjustment units includes:

[0011] A first operational amplifier, wherein a first terminal of the first operational amplifier is adapted to receive the input signal, a second terminal of the first operational amplifier is adapted to receive a reference signal, and an output terminal of the first operational amplifier outputs the adjustment signal.

[0012] A first adjustment module, coupled to the first operational amplifier, is used to provide the gain coefficient and a cutoff frequency adapted to the gain coefficient;

[0013] The gating module, coupled to the first operational amplifier, the control unit, and the first adjustment module respectively, is configured to be in a gating state or a de-gating state in response to the gating control signal, and when in the gating state, provides a gain coefficient corresponding to the gating first adjustment module.

[0014] In one embodiment, the first adjustment module includes: a first resistor, a first capacitor, and a plurality of coupled first adjustment branches, and each first adjustment branch includes: a second resistor and a second capacitor; wherein, for any two first adjustment modules, the resistance values ​​of their respective first resistors are the same, but the total resistance value of the second resistor corresponding to the first adjustment module with a larger gain coefficient is larger, and the total capacitance value is smaller.

[0015] In one embodiment, the first end of the first capacitor is coupled to the gating module, and the second end of the first capacitor is coupled to the first end of the first resistor; the second end of the first resistor is connected to the first end of the first operational amplifier and the first first adjustment branch of the plurality of first adjustment branches, respectively; the second resistor and the second capacitor in each first adjustment branch are connected in parallel and connected in series with the next first adjustment branch, and are coupled to the gating module.

[0016] In one embodiment, the gating module includes:

[0017] A first switch, which is coupled to the first adjustment module and the control unit respectively, is configured to be turned on or off in response to the gating control signal, and when turned on, transmits the input signal to the first terminal of the first operational amplifier;

[0018] A second switch, coupled to the output of the first operational amplifier and the control unit respectively, is configured to be turned on or off in response to the gating control signal, and to output the adjustment signal when turned on;

[0019] In this context, the first and second switches of the same gating module are simultaneously turned on or off in response to the gating control signal, while the first and second switches of other gating modules are turned off or turned on.

[0020] In one embodiment, at least one of the adjustment units includes an adjustment unit comprising:

[0021] A second operational amplifier, wherein a first terminal of the second operational amplifier is adapted to receive the input signal, a second terminal of the second operational amplifier is adapted to receive a reference signal, and an output terminal of the second operational amplifier outputs the adjustment signal;

[0022] Multiple second adjustment modules, each second adjustment module having a first terminal coupled to a first terminal of a second operational amplifier, a second terminal coupled to the output terminal of the second operational amplifier, and coupled to the control unit;

[0023] The third adjustment module is coupled to the first terminal of the second operational amplifier and the plurality of second adjustment modules respectively. When any second adjustment module is selected in response to the gating control signal, it provides the gain coefficient and a cutoff frequency adapted to the gain coefficient based on the selected second adjustment module and the third adjustment module.

[0024] In one embodiment, each of the second adjustment modules includes: a third switch, a fourth switch, and a plurality of second adjustment branches coupled between the third switch and the fourth switch, and each of the second adjustment branches includes: a third resistor and a third capacitor;

[0025] Specifically, for any two second adjustment modules, the third resistor of the second adjustment module with a larger gain coefficient has a larger total resistance but a smaller total capacitance, which is determined by all the third capacitors; and the third and fourth switches of the same second adjustment module are simultaneously turned on or off in response to the gating control signal, while the third and fourth switches of other second adjustment modules are turned off or turned on.

[0026] In one embodiment, the control unit is configured to generate a first gating control signal for controlling the gating gain coefficient to be greater than an initial gain coefficient when the amplitude of the adjustment signal is less than the amplitude of the preset signal; and to generate a second gating control signal for controlling the gating gain coefficient to be less than the initial gain coefficient when the amplitude of the adjustment signal is greater than the amplitude of the preset signal.

[0027] In one embodiment, the control unit is configured to estimate the strength of the input signal based on the current amplitude of the adjustment signal and the initial gain coefficient, and determine a target gain coefficient according to the amplitude of the preset signal; trigger gain switching control at the phase zero point or silent period of the input signal, select a fixed gain level adjacent to the target gain coefficient, and generate a duty cycle control signal accordingly, and perform high-speed switching between the adjacent fixed gain levels through an analog switch to obtain an equivalent fractional gain; within an adjustment window consisting of multiple modulation cycles, obtain the amplitude of the adjustment signal under the equivalent fractional gain, and adjust the fractional equivalent value according to the deviation between the amplitude of the adjustment signal and the amplitude of the preset signal until the deviation between the amplitude of the adjustment signal and the amplitude of the preset signal is within the target tolerance range.

[0028] Secondly, this application also provides a ranging device. The ranging device includes:

[0029] The phase adjustment circuit described in any of the foregoing embodiments includes: at least one adjustment unit and a control unit coupled to the adjustment unit;

[0030] The transmitting unit is used to transmit signals;

[0031] A receiving unit is used to receive the echo signal of the transmitted signal;

[0032] The control unit, coupled to the transmitting unit and the receiving unit respectively, is configured to obtain ranging results based on the transmitted signal and the echo signal;

[0033] When the adjustment unit is disposed between the control unit and the transmitting unit, the input signal is a driving signal, which is used to drive the transmitting unit to generate the transmitting signal; and / or when the adjustment unit is disposed between the receiving unit and the control unit, the input signal is the echo signal.

[0034] In one embodiment, the ranging device includes a phase-type laser ranging sensor;

[0035] The transmitting unit includes: one or more laser emitters;

[0036] The receiving unit includes: one or more detectors; and at least one laser emitter and at least one corresponding detector form a detection channel.

[0037] Thirdly, this application also provides a phase adjustment method. The phase adjustment method includes:

[0038] In response to the relationship between the adjustment signal and the preset signal, a gating control signal is generated;

[0039] In response to the gating control signal, the gain coefficient of the adjustment unit for adjusting the input signal is changed; wherein the adjustment signal is obtained by the adjustment unit adjusting the input signal according to the initial gain coefficient; and when the adjustment unit has different gain coefficients, the cutoff frequency corresponding to each gain coefficient is the same.

[0040] The aforementioned phase adjustment circuit and method, and ranging device, based on the adjustment signal and the preset signal, enable the control unit to generate a gating control signal to the adjustment unit. This allows the adjustment unit to change the gain coefficient used to adjust the input signal, thus enabling further adjustment of the input signal to obtain an adjustment signal that meets the ranging requirements. Furthermore, the adjustment unit operates at the same cutoff frequency for each gain coefficient, meaning that adjacent adjustment signals with different gain coefficients have the same or nearly the same phase delay. This ensures that any ranging process has a phase close to the true value, thereby improving ranging accuracy. Attached Figure Description

[0041] Figure 1 This is a schematic diagram illustrating the working mechanism of an operational amplifier circuit.

[0042] Figure 2 This is a schematic diagram of an adjustment circuit.

[0043] Figure 3 for Figure 2 Schematic diagram of the working mechanism under different states;

[0044] Figure 4 This is a schematic diagram of the structure of a phase adjustment circuit in an embodiment of this application;

[0045] Figure 5 This is a schematic diagram of the structure of the first adjustment unit in the embodiments of this application;

[0046] Figure 6 This is a schematic diagram of the specific structure of the first adjustment unit in the embodiments of this application;

[0047] Figure 7 for Figure 6 Schematic diagram of the working mechanism under different states;

[0048] Figure 8 This is a schematic diagram of the structure of the second type of adjustment unit in the embodiments of this application;

[0049] Figure 9 This is a schematic diagram of the specific structure of the second type of adjustment unit in the embodiments of this application;

[0050] Figure 10 This is a schematic diagram of the structure of a ranging device in an embodiment of this application;

[0051] Figure 11 This is a flowchart of a phase adjustment method in an embodiment of this application. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0053] As described in the background section, dynamic range is a key performance indicator for laser rangefinders (e.g., phase-detection laser rangefinders). Generally, high-performance laser rangefinders need to meet a dynamic range of 100 to 10,000.

[0054] For precision phase-based laser ranging products, low phase detection error and high ranging stability are required throughout the entire ranging range.

[0055] To better understand and explain the shortcomings of the existing solutions, we will first briefly introduce the working mechanism of the operational amplifier circuit.

[0056] See Figure 1 The diagram shown illustrates the working principle of an operational amplifier circuit. Figure 1 The overall theoretical amplitude-frequency characteristics of the operational amplifier circuit are shown. Among them, Figure (a) is the frequency-gain curve, and Figure (b) is the frequency-phase curve.

[0057] Depend on Figure 1 It can be seen that as the input signal frequency gradually increases to near the cutoff frequency f P At this point, the gain G begins to decrease, and the phase of the input / output signal begins to change. Theoretically, at f... SIG =f P When the output signal is in phase, it undergoes a 45° phase shift relative to the input signal, which results in a phase delay.

[0058] To meet the dynamic range of 100 to 10000, operational amplifier circuits are used in the ranging device to amplify the input signal with different gain coefficients, thereby meeting different ranging requirements.

[0059] Specifically, the dynamic range extension of operational amplifier circuits is generally achieved by using analog switches to adjust the circuit gain. This allows for the use of low-gain circuits to prevent circuit saturation when the signal is strong, while high-gain circuits are used to improve the signal-to-noise ratio when the signal is weak, thus meeting measurement requirements.

[0060] However, during dynamic range adjustment, different ranging processes correspond to different gain coefficients in the operational amplifier circuit, resulting in different phase delays when the amplifier circuit switches gain coefficients. In other words, different gain coefficients have different phases.

[0061] See Figure 2 The diagram shows the structure of an adjustment circuit, as follows: Figure 2 As shown, the adjustment circuit may include: an operational amplifier 201, an input resistor 202, a first feedback resistor 203 and a second feedback resistor 204, as well as a first analog switch 205 and a second analog switch 206.

[0062] Taking an inverting amplifier circuit as an example, the gain of the adjustment circuit is determined by the ratio of the first feedback resistor 203 or the second feedback resistor 204 to the input resistor 202. The first analog switch 205 and the second analog switch 206 are generally controlled by a controller, such as a digital circuit like an MCU or FPGA. Furthermore, the following condition must be met: the resistance R of the second feedback resistor 204... FH The resistance R is greater than that of the first feedback resistor 203. LH And all of them are greater than the resistance R of the input resistor 202. IN .

[0063] When the first analog switch 205 is closed and the second analog switch 206 is open, the gain is G. H =-(R) FH / R IN When the first analog switch 205 is open, the gain is G, and when the second analog switch 206 is closed and the first analog switch 205 is open, the gain is G. L =-(R) LH / R IN It is in the low gain setting.

[0064] Thus, based on different ranging requirements, the signal can be enhanced or weakened by closing or opening the first analog switch 205 or the second analog switch 206.

[0065] However, during the switching process of the first analog switch 205 and the second analog switch 206, different pairs of phase delays will be generated.

[0066] See Figure 3 shown Figure 2 The schematic diagrams of the working mechanism under different states show that, since the product of the gain (Gain) and bandwidth (BW) of operational amplifier 201 is a constant, as shown in the diagrams... Figure 3 As shown in (a), the amplitude-frequency response curve 207 of the adjustment circuit at the high gain level does not coincide with the amplitude-frequency response curve 208 at the low gain level.

[0067] This causes the adjustment circuit to operate at the cutoff frequency f in the high-gain range. PH It must be lower than the cutoff frequency f of the low-gain setting. PL Therefore, in such Figure 3 In the frequency-phase curve shown in (b), the fixed frequency signal f SIG There is a significant phase difference at the intersection of phase curve 209 of the high-gain circuit and phase curve 210 of the low-gain circuit. This will cause a phase delay introduced by adjusting the dynamic range of the circuit during ranging, resulting in ranging errors.

[0068] To address the aforementioned technical problems, this application provides a phase adjustment circuit and method, and a ranging device. Based on an adjustment signal and a preset signal, the control unit generates a gating control signal for the adjustment unit, enabling the adjustment unit to change the gain coefficient used to adjust the input signal. This allows for further adjustment of the input signal to obtain an adjustment signal that meets the ranging requirements. Furthermore, the adjustment unit operates at the same cutoff frequency for each gain coefficient, meaning that adjustment signals at adjacent gain coefficients have the same or nearly the same phase delay. This ensures that any ranging process has a phase close to the true value, thereby improving ranging accuracy.

[0069] See Figure 4 The schematic diagram shown in this application illustrates the structure of a phase adjustment circuit in an embodiment of the present application. Figure 4 As shown, the phase adjustment circuit 400 may include:

[0070] At least one adjustment unit 410 is configured to adjust the input signal S according to an initial gain coefficient. IN Adjustments are made, generating an adjustment signal S. OUT ; and in response to the gating control signal S c , change the input signal S IN The gain coefficients are adjusted; where, when the adjustment unit 410 has different gain coefficients, the cutoff frequency corresponding to each gain coefficient is the same.

[0071] Control unit 420, coupled to adjustment unit 410, is configured to adjust according to adjustment signal S OUT Combined with a preset signal, a gating control signal S is generated. c To the adjustment unit 410.

[0072] Specifically, at the initial moment, when the adjustment unit 410 is in the working state, it corresponds to a gain coefficient, namely the initial gain coefficient. Thus, the adjustment unit 410 can adjust the input signal S according to this initial gain coefficient. IN Adjustments are made, generating an adjustment signal S. OUT .

[0073] During ranging, an input signal S IN This typically corresponds to a preset signal. Thus, even with the input signal S... IN Even when the parameters are unknown, the control unit 420 can still determine whether the adjustment signal generated from the initial gain coefficient meets the requirements based on the adjustment signal and the preset signal, and then generate the gating control signal S. c To the adjustment unit 410.

[0074] In the gating control signal S c Under the influence of the adjustment unit 410, the adjustment unit 410 performs at least the following processes: maintaining the initial gain coefficient, increasing the initial gain coefficient, and decreasing the initial gain coefficient. Thus, the adjustment unit 410 can use the changed gain coefficient to adjust the adjustment signal so that the adjustment signal meets the requirements of the preset signal.

[0075] This allows for the acquisition of an adjustment signal that meets the ranging requirements. Furthermore, by ensuring that the cutoff frequency for each gain coefficient is the same, the adjustment signal at each gain coefficient has the same or nearly the same phase delay. Since the phase delay reflects the phase difference between adjacent ranging processes, this means that any two ranging processes have the same or nearly the same phase, thus improving ranging accuracy.

[0076] In some embodiments, a corresponding number of adjustment units can be set according to different application scenarios. In this way, the input signal can be adjusted by selecting adjustment units with different gain coefficients or by adjusting the gain coefficient of the same adjustment unit.

[0077] Example 1

[0078] In Embodiment 1, at least one adjustment unit includes multiple adjustment units, any two adjustment units have different gain coefficients, but any two adjustment units have the same cutoff frequency.

[0079] Since any two adjustment units have different gain coefficients, the input signal can be adjusted to different gains, thus obtaining an adjustment signal that meets the ranging requirements. Furthermore, since any two adjustment units have the same cutoff frequency, any two ranging processes will have a low phase difference.

[0080] Furthermore, by having one adjustment unit corresponding to one gain coefficient, and each ranging process being independent of each other, the influence between different adjustment units can be reduced, resulting in a better adjustment effect.

[0081] See Figure 5 The schematic diagram of the structure of the first adjustment unit in the embodiment of this application is shown below. Figure 5 As shown, the adjustment unit 410 may include:

[0082] The first operational amplifier 411 has a first terminal (e.g., an inverting input terminal) adapted to receive an input signal, a second terminal (e.g., a non-inverting input terminal) adapted to receive a reference signal, and an output terminal of the first operational amplifier 411 outputting an adjustment signal.

[0083] The first adjustment module 412 is coupled to the first operational amplifier 411 and is used to provide a gain coefficient and a cutoff frequency adapted to the gain coefficient.

[0084] The gating module 413 is coupled to the first operational amplifier 411, the control unit 420 and the first adjustment module 412 respectively, and is configured to be in a gating state or a de-gating state in response to the gating control signal, and when in the gating state, it provides a gain coefficient corresponding to the gating first adjustment module 412.

[0085] Specifically, the first operational amplifier 411 and the first adjustment module 412 form a gain adjustment circuit, which work together to provide gain coefficients (including initial gain coefficients and current gain coefficients). The gating module 413 acts as a switch; when the gating module 413 is selected, the first adjustment module 412 coupled to it can be connected to the phase adjustment circuit, allowing the phase adjustment circuit to adjust the input signal S based on the gain coefficient corresponding to the first adjustment module 412. IN Adjustments will be made.

[0086] In one embodiment, when one gating module 413 is selected, the gating modules 413 in the other adjustment units 410 are deselected. That is, at any given time, only one gating module 413 in the adjustment unit 410 is selected. This configuration achieves independence between the different adjustment units 410, further reducing the phase difference generated during the switching process of the different adjustment units 410.

[0087] In one embodiment, the gain coefficient of the adjustment unit 410 is provided by its respective first adjustment module 412. Although the gain coefficient of each first adjustment module 412 is different, by adjusting the first adjustment module 412, the cutoff frequency provided by each first adjustment module 412 is made consistent.

[0088] In one embodiment, the first adjustment module 412 may include: a first resistor, a first capacitor, and a plurality of coupled first adjustment branches, and each first adjustment branch includes: a second resistor and a second capacitor. Thus, the gain coefficient provided by each first adjustment module 412 is determined by the total resistance of the first resistor and the second resistors in all the first adjustment branches, while the total capacitance of the first capacitor and the second capacitors in all the first adjustment branches determines the cutoff frequency.

[0089] In one embodiment, for any two first adjustment modules, the resistance values ​​of their respective first resistors are the same, but the total resistance value of the second resistor corresponding to the first adjustment module with a larger gain coefficient is larger, and the total capacitance value is smaller.

[0090] In other words, this application configures the total resistance of the first resistor and the second resistors in all the first adjustment branches to make each adjustment unit have a different gain coefficient; and configures the total capacitance of the first capacitor and all the second capacitors to make each adjustment unit have the same cutoff frequency.

[0091] For example, see Figure 6 The schematic diagram shown in this application illustrates the specific structure of an adjustment unit in an embodiment of the present application, as follows: Figure 6 As shown, an adjustment unit with two first adjustment modules is illustrated, each first adjustment module having two first adjustment branches. This application does not limit the number of first adjustment modules and first adjustment branches.

[0092] like Figure 6 As shown, one of the first adjustment modules includes: a first resistor R11, a first capacitor C11, and each first adjustment branch includes: a second resistor R121, a second capacitor C121; or, a second resistor R122, a second capacitor C122; while the other first adjustment module includes: a first resistor R21, a first capacitor C21, and multiple coupled first adjustment branches, each first adjustment branch including: a second resistor R221, a second capacitor C221; or, a second resistor R222, a second capacitor C222.

[0093] And it satisfies the following: the resistance value of the first resistor R11 is the same as the resistance value of the first resistor R21, so that the input signal S IN They have the same input impedance; the total resistance of the second resistor R121 and the second resistor R122 is greater than the total resistance of the second resistor R221 and the second resistor R222. Thus, when the resistance of the first resistor R11 is the same as that of the first resistor R21, the two first adjustment modules can provide different gain coefficients.

[0094] It should be noted that the resistance value of the first resistor R11 can be different from that of the first resistor R21, as long as the ratio of the total resistance of the second resistor R121 and the second resistor R122 to the resistance value of the first resistor R11 is different from the ratio of the total resistance of the second resistor R221 and the second resistor R222 to the resistance value of the first resistor R21.

[0095] In some embodiments, the capacitance values ​​of the first capacitor C11 and the first capacitor C21 are the same, while the total capacitance value between the second capacitors C121 and C122 is different from the total capacitance value between the second capacitors C221 and C222. This allows the two first adjustment modules to provide the same cutoff frequency when the capacitance values ​​of the first capacitors C11 and C21 are the same.

[0096] It should be noted that the capacitance values ​​of the first capacitor C11 and the first capacitor C21 can also be different, as long as the cutoff frequencies formed by the resistor and the capacitor are different.

[0097] Accordingly, the first terminal of the first capacitor C11 is coupled to the gating module 413, and the second terminal of the first capacitor C11 is coupled to the first terminal of the first resistor R11. The second terminal of the first resistor R11 is connected to the first terminal of the first operational amplifier 411 and the first first adjustment branch of the plurality of first adjustment branches, respectively. The second resistor and the second capacitor in each first adjustment branch are connected in parallel and connected in series with the next first adjustment branch, and coupled to the gating module 413.

[0098] For example, the second resistor R121 and the second capacitor C121 are connected in parallel, and are connected in series with the first adjustment branch formed by the second resistor R122 and the second capacitor C122 connected in parallel. The first adjustment branch formed by the second resistor R122 and the second capacitor C122 connected in parallel is coupled to the gating module 413.

[0099] That is, this application reduces phase delay by using multi-stage circuits.

[0100] The gating module 413 may include:

[0101] The first switch K11, which is coupled to the first adjustment module 412 and the control unit 420 respectively, is configured to respond to the gating control signal S. c It is either selected or deselected, and when selected, the input signal S is... IN Transmitted to the first terminal of the first operational amplifier 411;

[0102] The second switch K12, which is coupled to the output of the first operational amplifier 411 and the control unit 420 respectively, is configured to respond to the gating control signal S. c It is either selected or deselected, and when selected, the output adjustment signal S is activated. OUT .

[0103] In other words, the gain coefficient can be connected by simultaneously turning on or off the first switch K11 and the second switch K12, and the gain coefficient can be dynamically changed by selecting the first switch and the second switch of different branches (e.g., the first switch K21 and the second switch K22).

[0104] In some embodiments, the first and second switches of the same gating module are simultaneously turned on or off in response to a gating control signal, while the first and second switches of other gating modules are turned off or on. That is, at any given time, only the first and second switches of one gating module are simultaneously in the turned-on state.

[0105] In other words, the first and second switches of the same gating module are interconnected, and are mutually exclusive with the first and second switches of other gating modules.

[0106] Furthermore, the reason why this application includes a first switch and a second switch in the gating module is that: the first operational amplifiers of different adjustment units share the same output terminal. When one of the first operational amplifiers is activated, the other first operational amplifiers may be in a high-impedance state, and their output impedance may form a reverse path, interfering with the output signal of the first operational amplifier. For example, they may form a parallel load with the unselected first operational amplifier, reducing the signal amplitude. By setting two switches, the physical isolation characteristics of the switches reduce the capacitive load at the output terminal, so that only the selected first operational amplifier drives the subsequent circuit, achieving isolation between different first operational amplifiers.

[0107] It should be noted that, firstly, the descriptions of other driving units can be found in the foregoing examples; secondly, the first switch and the second switch can be any device or circuit with both on and off states, and this application does not limit the types of the first switch and the second switch. In some examples, to reduce the impact on different driving units, the first switch and the second switch are of the same type.

[0108] In some embodiments, see below. Figure 6 ,Depend on Figure 6 It can be seen that each driving unit has the same input signal S IN and reference signal S ref This ensures that the cutoff frequency is only related to the selected drive unit.

[0109] Thus, by employing a drive unit with the aforementioned characteristics, the phase error caused by amplifier circuits with different gain coefficients is reduced.

[0110] See Figure 7 shown Figure 6 The working mechanism diagram under different states, in Figure 6Two drive units with different gain-bandwidth products (GBW) are used; for example, the gain-bandwidth product of the first drive unit is greater than that of the second drive unit.

[0111] Correspondingly, the gain coefficient of the high-gain drive circuit is the ratio between the total resistance of the second resistors R121 and R122 and the resistance of the first resistor R11, and the gain coefficient of the low-gain circuit is the ratio between the total resistance of the second resistors R221 and R222 and the first resistor R21.

[0112] like Figure 7 As shown in Figure (a), by appropriately adjusting the relevant parameters of the two driving units, the cutoff frequency of the frequency-gain curve 701 of the high-gain circuit and the cutoff frequency of the frequency-gain curve 702 of the low-gain circuit are made as equal as possible.

[0113] At this time, as Figure 7 As shown in Figure (b), the frequency-phase curves 703 and 704 of the high / low gain amplifier circuits exhibit basically the same variation pattern (or the error between the two curves is very small near the frequency range of the measured signal), and the phase error introduced by the corresponding circuit switching will be greatly reduced.

[0114] Example 2

[0115] In Embodiment 2, at least one adjustment unit includes an adjustment unit, which includes multiple adjustment branches, each with a different gain but the same cutoff frequency.

[0116] See Figure 8 The schematic diagram of the structure of the second type of adjustment unit in the embodiment of this application is shown below. Figure 8 As shown, the adjustment unit 410 may include:

[0117] The second operational amplifier 421, the first terminal of the second operational amplifier 421 (e.g., the inverting input terminal) is adapted to receive the input signal S. IN The second terminal (e.g., the non-inverting input) of the second operational amplifier is adapted to receive the reference signal S. ref The output of the second operational amplifier 421 outputs an adjustment signal S. OUT ;

[0118] Multiple second adjustment modules (e.g.) Figure 8 The schematic second adjustment modules 4221 and 4222 are shown. The first end of each second adjustment module is coupled to the first end of the second operational amplifier 421, and the second end of each second adjustment module is coupled to the output end of the second operational amplifier 421 and to the control unit 420.

[0119] The third adjustment module 423 is coupled to the first terminal of the second operational amplifier 421 and the plurality of second adjustment modules respectively. When any second adjustment module is selected in response to the gating control signal, it provides a gain coefficient and a cutoff frequency adapted to the gain coefficient based on the selected second adjustment module and the third adjustment module.

[0120] Specifically, at any given time, one of the multiple second adjustment modules is selected, so that the selected second adjustment module works in conjunction with the third adjustment module 423 and together with the second operational amplifier 421 to provide a gain coefficient.

[0121] That is, only one second adjustment module is selected at any given time. This configuration ensures independence between different second adjustment modules, further reducing the phase difference during switching between them, and also reducing the overall circuit area.

[0122] In one embodiment, the gain coefficient of the adjustment unit 410 is provided by the selected second adjustment module and third adjustment module 423. Although each provided gain coefficient is different, by adjusting the second adjustment module and / or the third adjustment module 423, the cutoff frequency corresponding to each gain coefficient is made consistent.

[0123] In one embodiment, each second adjustment module may include a third switch, a fourth switch, and a plurality of second adjustment branches coupled between the third switch and the fourth switch, and each second adjustment branch includes a third resistor and a third capacitor. Thus, the gain coefficient can be determined by the third resistor, while the third capacitor determines the cutoff frequency.

[0124] In one embodiment, for any two second adjustment modules, the third resistor of the second adjustment module with a larger gain coefficient has a larger total resistance but a smaller total capacitance, which is determined by all the third capacitors; and the third and fourth switches of the same second adjustment module are simultaneously turned on or off in response to the gating control signal, while the third and fourth switches of other second adjustment modules are turned off or turned on.

[0125] In other words, this application configures the total resistance value of the third resistor of each second adjustment module so that each second adjustment module has a different gain coefficient when it is selected; and configures the total capacitance value of the third capacitor so that each second adjustment module has the same cutoff frequency when it is selected.

[0126] For example, see Figure 9 The schematic diagram of the specific structure of the second type of adjustment unit in the embodiments of this application is shown below. Figure 9As shown, an adjustment unit with two second adjustment modules is illustrated, each second adjustment module having two second adjustment branches. This application does not limit the number of second adjustment modules and second adjustment branches.

[0127] like Figure 9 As shown, one of the second adjustment modules includes: a third switch K31, a fourth switch K32, and a second adjustment branch coupled between the third switch K31 and the fourth switch K32, consisting of a third resistor R311 and a third capacitor C311 connected in parallel, and a second adjustment branch consisting of a third resistor R312 and a third capacitor C312 connected in parallel; while the other second adjustment module includes: a third switch K41, a fourth switch K42, and a second adjustment branch coupled between the third switch K41 and the fourth switch K42, consisting of a third resistor R321 and a third capacitor C321 connected in parallel, and a second adjustment branch consisting of a third resistor R322 and a third capacitor C322 connected in parallel.

[0128] Furthermore, the following condition must be met: the total resistance of the third resistors R311 and R312 is different from the total resistance of the third resistors R321 and R322, so that the two second adjustment modules provide different gain coefficients.

[0129] In some embodiments, the total capacitance of the third capacitors C311 and C312 is different from the total capacitance of the third capacitors C321 and C322, so that the two second adjustment modules provide the same cutoff frequency.

[0130] Accordingly, the first terminal of the third switch K31 is coupled to the first terminal of the third adjustment module 423, the second operational amplifier 421, and the control unit 420 respectively; the first terminal of the third switch K31 is coupled to the first terminal of the third resistor R311 and the third capacitor C311 respectively; the second terminals of the third resistor R31 and the third capacitor C31 are coupled to the first terminals of the third resistor R312 and the third capacitor C312 respectively; the second terminals of the third resistor R312 and the third capacitor C312 are coupled to the first terminal of the fourth switch K32; and the second terminal of the fourth switch K32 is coupled to the output terminal of the second operational amplifier 421.

[0131] For a description of the other second adjustment modules, please refer to the example above.

[0132] The third adjustment module 423 may include a fourth resistor R33.

[0133] In some alternative examples, the third adjustment module 423 may also include a fourth capacitor, which is coupled to the second operational amplifier via a fourth resistor R33.

[0134] In some embodiments, the gain coefficient is accessed by simultaneously turning on or off the third switch K31 and the fourth switch K32, and the gain coefficient is dynamically changed by selecting the third and fourth switches of different branches (e.g., the third switch K41 and the fourth switch K42).

[0135] In some embodiments, the third and fourth switches of the same second adjustment module are simultaneously turned on or off in response to a gating control signal, while the third and fourth switches of other second adjustment modules are turned off or turned on. That is, at any given time, only the third and fourth switches of one second adjustment module are simultaneously in the turned-on state.

[0136] In other words, the third and fourth switches of the same second adjustment module are interconnected, and are mutually exclusive with the third and fourth switches of other second adjustment modules.

[0137] It should be noted that, firstly, the descriptions of other second adjustment modules can be found in the foregoing examples; secondly, the third and fourth switches can be any devices or circuits with both on and off states, and this application does not limit the types of the third and fourth switches. In some examples, to reduce the impact on different second adjustment modules, the third and fourth switches are of the same type.

[0138] In some embodiments, see below. Figure 9 ,Depend on Figure 9 It can be seen that each second adjustment module has the same input signal S IN and reference signal S ref This ensures that the cutoff frequency is only related to the selected second adjustment module.

[0139] In some embodiments, the control unit is configured to generate a first gating control signal for controlling the gating gain coefficient to be greater than an initial gain coefficient when the amplitude of the adjustment signal is less than the amplitude of a preset signal; and to generate a second gating control signal for controlling the gating gain coefficient to be less than an initial gain coefficient when the amplitude of the adjustment signal is greater than the amplitude of the preset signal.

[0140] In other words, when the amplitude of the adjustment signal is small, a larger gain coefficient is selected to increase the amplitude of the adjustment signal; when the amplitude of the adjustment signal is large, a smaller gain coefficient is selected to decrease the amplitude of the adjustment signal. In this way, through such dynamic adjustment, the ranging error caused by a stronger optical signal at close range and a weaker optical signal at long range can be avoided.

[0141] In some embodiments, the control unit may execute the following process to determine the gain coefficient to be selected at the next moment.

[0142] A1) Based on the current amplitude of the adjusted signal and the initial gain coefficient, estimate the strength of the input signal, and determine the target gain coefficient according to the amplitude of the preset signal.

[0143] Specifically, for any adjustment unit with a given gain coefficient, the amplitude of its input signal is fixed, and the initial gain coefficient is also fixed. The current amplitude of the adjustment signal generated by the adjustment unit is measured by a detector (e.g., an analog-to-digital converter), and is therefore known.

[0144] In this way, the estimated value of the input signal can be determined based on the current amplitude and initial gain coefficient of the adjusted signal.

[0145] Right now: Among them, A in A is an estimate of the input signal. out To adjust the current amplitude of the signal, and G cur This is the initial gain coefficient.

[0146] Next, the target gain coefficient can be determined based on the amplitude of the preset signal and the estimated value of the input signal.

[0147] Right now: Among them, G tg Let A be the target gain coefficient. tg The amplitude of the preset signal.

[0148] A2) At the zero point or quiet period of the input signal phase, trigger the gain switching control, select the fixed gain level adjacent to the target gain coefficient, and generate a duty cycle control signal accordingly. Use an analog switch to switch at high speed between adjacent fixed gain levels to obtain an equivalent fractional gain.

[0149] In some embodiments, the difference between the current amplitude of the adjustment signal and the amplitude of the preset signal is within a certain range, and the current amplitude of the adjustment signal is qualified and can be used for ranging. Therefore, when determining the target gain coefficient, it is first necessary to further determine which gain coefficient is selected.

[0150] Based on this, when determining the gain coefficient corresponding to the adjustment unit, a series of fixed gain levels can be determined, namely: G1, G2, ..., G... n Thus, it is possible to base the target gain coefficient G on... tg Select the adjacent fixed gain level [G] i G i+1 ], where i is taken from [1, n-1], and G i+1 Greater than G i .

[0151] Then, by using two adjacent fixed gain levels and switching them in a time-division manner (adjusted by duty cycle), the amplitude of the output signal gradually approaches the target amplitude over multiple modulation cycles, and finally stabilizes the output signal within the tolerance range of the target amplitude, so as to obtain the fractional equivalent value of the target gain coefficient.

[0152] The zero point of the phase refers to the zero-crossing point of the input signal, that is, the instantaneous position of the signal waveform crossing the time axis from the positive half-cycle to the negative half-cycle (or in the opposite direction).

[0153] The silent period refers to the brief interval between two consecutive complete cycles in a periodic modulation signal. In laser ranging, no effective modulation signal is emitted during this period.

[0154] A3) Within an adjustment window consisting of multiple modulation cycles, obtain the amplitude of the adjusted signal under the equivalent fractional gain. Adjust the fractional equivalent value according to the deviation between the amplitude of the adjusted signal and the amplitude of the preset signal until the deviation between the amplitude of the adjusted signal and the amplitude of the preset signal is within the target tolerance range.

[0155] Specifically, by performing step A2), the equivalent fractional gain D of the target gain coefficient can be determined. Then, based on the equivalent fractional gain D and the adjacent fixed gain level, the equivalent gain coefficient of the target gain coefficient can be determined.

[0156] That is, G eq = (1-D)*G i +D*G i+1 .

[0157] In this way, the input signal can be adjusted using an equivalent gain coefficient. Then, based on the deviation between the amplitude of the adjusted signal and the amplitude of the preset signal, the fractional equivalent value is adjusted until the deviation between the amplitude of the adjusted signal and the amplitude of the preset signal is within the target tolerance range.

[0158] In some embodiments, multiple adjacent fixed gain levels may be obtained. Therefore, when selecting the final candidate gain level, the cost functions of amplitude error and phase error should be considered simultaneously, and the optimal level combination should be selected by comparing the cost of different candidate combinations.

[0159] For example, for each candidate combination, its equivalent gain coefficient under the equivalent fractional gain D is g. eq .

[0160] Then A pref =A in *G eq Then the amplitude error E A =|A pref -A tgt |

[0161] Simultaneously, the inherent phase difference φ of the candidate combination is read from the offline calibration table. off And combined with the real-time phase drift φ obtained by online demodulation line The phase error is obtained as E. φ =|φ off +φ line |

[0162] The offline calibration table can be obtained through offline calibration experiments.

[0163] Specifically, the sensor is placed on a standard target surface at a known fixed distance, and different gain levels are switched one by one; an optical signal with a known modulation frequency is received and demodulated to obtain the measured phase; the measured phase is compared with the theoretical phase to obtain the inherent phase difference under this combination; the "gain level-frequency" is used as an index and stored in a table together with the measured inherent phase difference; the above process is repeated to cover all candidate combinations, thereby forming a complete offline calibration table.

[0164] Online demodulation involves acquiring signals from the receiving end during operation, obtaining in-phase and quadrature components; calculating the instantaneous phase using the arctangent function; and then obtaining the real-time phase through phase expansion and filtering.

[0165] Thus, a bi-objective cost function can be constructed:

[0166]

[0167] Where, ω A and ω φ The weighting parameter A is used to adjust the contribution ratio of amplitude error and phase error in the total cost function. ε φ represents a constant. ref This indicates a reference phase value, such as a preset phase.

[0168] The cost value is calculated sequentially for all candidate combinations, and the combination with the smallest cost value is selected as the final gain level combination.

[0169] Based on the same inventive concept, this application also provides a ranging device that implements the phase adjustment circuit described above. The solution provided by this ranging device is similar to the solution described in the above method; therefore, the specific limitations in one or more embodiments provided below can be found in the limitations of the phase adjustment circuit described above, and will not be repeated here.

[0170] See Figure 10 The schematic diagram shown in this application illustrates the structure of a ranging device 1000, which may include:

[0171] The phase adjustment circuit of any of the foregoing embodiments includes: at least one adjustment unit 410, and a control unit 420 coupled to the adjustment unit 410;

[0172] Transmitting unit 1010 is used to transmit signals;

[0173] The receiving unit 1020 is used to receive the echo signal of the transmitted signal;

[0174] The control unit 420, coupled to the transmitting unit 1010 and the receiving unit 1020 respectively, is configured to acquire ranging results based on the transmitted signal and the echo signal.

[0175] Specifically, by using the aforementioned adjustment unit 410 in the ranging device 1000, the amplitude of the transmitted signal emitted by the transmitting unit 1010 and / or the echo signal received by the receiving unit 1020 can be adjusted in real time, and the phase difference under different gain coefficients can be guaranteed so that the amplitude of the transmitted signal is different but the cutoff frequency is the same, and / or the amplitude of the echo signal is different but the cutoff frequency is the same, in different adjustment processes.

[0176] In some embodiments, when the adjustment unit 410 is disposed between the control unit 420 and the transmitting unit 1010, the input signal is a driving signal, which is used to drive the transmitting unit 1010 to generate a transmitting signal.

[0177] And / or, when the adjustment unit 410 is positioned between the receiving unit 1020 and the control unit 420, the input signal is an echo signal.

[0178] In some embodiments, the control unit 420 may be implemented by a processing chip such as a central processing unit (CPU), a field programmable gate array (FPGA), or a programmable logic controller (PLC), or by an application specific integrated circuit (ASIC) or one or more integrated circuits configured to implement embodiments of the present invention.

[0179] For example, as a specific example, the control unit 420 may be a central processing unit.

[0180] In some embodiments, the transmitting unit 1010 may include one or more laser transmitters; the receiving unit 1020 may include one or more detectors L02 for receiving the echo of the transmitted signal after it has been reflected by one or more objects in the environment and generating an echo signal.

[0181] As an example, the laser emitter in the emitting unit 1010 can be arranged as a two-dimensional array, and the laser emitter may include a vertical cavity surface-emitting laser (VCSEL). The light emitted by the laser emitter is shaped by an emitting lens group (not shown) and emitted in different directions to cover the field of view (FOV) of the ranging device.

[0182] As an example, one or more detectors in the receiving unit 1020 may include at least one of avalanche photodiode (APD), single photon avalanche diode (SPAD), and silicon photomultiplier (SiPM), arranged in a two-dimensional array and corresponding to the arrangement of the laser emitter to form multiple detection channels with the laser emitter in the transmitting module.

[0183] In some embodiments, each detection channel may include a laser emitter and one or more detectors, or may consist of one or more lasers and one detector, or may include multiple laser emitters and multiple detectors. The light signal emitted by a laser in the same detection channel, after being reflected by an object, can be received by a detector in that same detection channel. The sub-fields of view of all detection channels together constitute the FOV of the entire ranging device.

[0184] In some embodiments, the ranging device includes a phase-type laser ranging sensor.

[0185] Based on the same inventive concept, this application also provides a phase adjustment method for implementing the phase adjustment circuit described above. The solution provided by this phase adjustment method is similar to the implementation described in the above method; therefore, the specific limitations in one or more embodiments provided below can be found in the limitations of the phase adjustment circuit described above, and will not be repeated here.

[0186] See Figure 11 The flowchart of a phase adjustment method in an embodiment of this application is shown below. Figure 11 As shown, the following steps can be performed:

[0187] S111 generates a gating control signal in response to the relationship between the adjustment signal and the preset signal.

[0188] S112, in response to the gating control signal, changes the gain coefficient of the adjustment unit to adjust the input signal; wherein, the adjustment signal is obtained by the adjustment unit adjusting the input signal according to the initial gain coefficient; and when the adjustment unit has different gain coefficients, the cutoff frequency corresponding to each gain coefficient is the same.

[0189] Specifically, at the initial moment, when the adjustment unit is in the working state, there is a corresponding gain coefficient, namely the initial gain coefficient. In this way, the adjustment unit can adjust the input signal according to the initial gain coefficient to generate the adjusted signal.

[0190] During ranging, one input signal typically corresponds to one preset signal. This allows the system to determine whether the adjustment signal generated from the initial gain coefficient meets the requirements, even when the parameters of the input signal are unknown, based on the adjustment signal and the preset signal, and then generate a gating control signal for the adjustment unit.

[0191] Under the influence of the gating control signal, the adjustment unit performs at least the following processes: maintaining the initial gain coefficient, increasing the initial gain coefficient, and decreasing the initial gain coefficient. Thus, the adjustment unit can use the changed gain coefficient to adjust the adjustment signal so that the adjustment signal meets the requirements of the preset signal.

[0192] This allows for the acquisition of an adjustment signal that meets the ranging requirements. Furthermore, by ensuring that the cutoff frequency for each gain coefficient is the same, the adjustment signal at each gain coefficient has the same or nearly the same phase delay. Since the phase delay reflects the phase difference between adjacent ranging processes, this means that any two ranging processes have the same or nearly the same phase, thus improving ranging accuracy.

[0193] For more details on phase adjustment methods, please refer to the examples above.

[0194] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0195] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0196] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A phase adjustment circuit, characterized in that, include: At least one adjustment unit is configured to adjust the input signal according to an initial gain coefficient to generate an adjustment signal; And in response to a gating control signal, the gain coefficient used to adjust the input signal is changed; wherein, when the adjustment unit has different gain coefficients, the cutoff frequency corresponding to each gain coefficient is the same; The control unit, coupled to the adjustment unit, is configured to generate the gating control signal to the adjustment unit based on the adjustment signal and a preset signal.

2. The phase adjustment circuit according to claim 1, characterized in that, At least one of the adjustment units includes multiple adjustment units, any two of the adjustment units have different gain coefficients, but any two of the adjustment units have the same cutoff frequency.

3. The phase adjustment circuit according to claim 2, characterized in that, Each of the aforementioned adjustment units includes: A first operational amplifier, wherein a first terminal of the first operational amplifier is adapted to receive the input signal, a second terminal of the first operational amplifier is adapted to receive a reference signal, and an output terminal of the first operational amplifier outputs the adjustment signal. A first adjustment module, coupled to the first operational amplifier, is used to provide the gain coefficient and a cutoff frequency adapted to the gain coefficient; The gating module, coupled to the first operational amplifier, the control unit, and the first adjustment module respectively, is configured to be in a gating state or a de-gating state in response to the gating control signal, and when in the gating state, provides a gain coefficient corresponding to the gating first adjustment module.

4. The phase adjustment circuit according to claim 3, characterized in that, The first adjustment module includes: a first resistor, a first capacitor, and multiple coupled first adjustment branches, and each first adjustment branch includes: a second resistor and a second capacitor; Among them, for any two first adjustment modules, the resistance values ​​of their respective first resistors are the same, but the total resistance value of the second resistor corresponding to the first adjustment module with a larger gain coefficient is larger, and the total capacitance value is smaller.

5. The phase adjustment circuit according to claim 4, characterized in that, The first terminal of the first capacitor is coupled to the gating module, and the second terminal of the first capacitor is coupled to the first terminal of the first resistor. The second terminal of the first resistor is connected to the first terminal of the first operational amplifier and the first first adjustment branch of the plurality of first adjustment branches, respectively. The second resistor and the second capacitor in each first adjustment branch are connected in parallel and connected in series with the next first adjustment branch, and are coupled to the gating module.

6. The phase adjustment circuit according to claim 3, characterized in that, The gating module includes: A first switch, which is coupled to the first adjustment module and the control unit respectively, is configured to be turned on or off in response to the gating control signal, and when turned on, transmits the input signal to the first terminal of the first operational amplifier; A second switch, coupled to the output of the first operational amplifier and the control unit respectively, is configured to be turned on or off in response to the gating control signal, and to output the adjustment signal when turned on; In this context, the first and second switches of the same gating module are simultaneously turned on or off in response to the gating control signal, while the first and second switches of other gating modules are turned off or turned on.

7. The phase adjustment circuit according to claim 1, characterized in that, At least one of the adjustment units includes an adjustment unit, the adjustment unit comprising: A second operational amplifier, wherein a first terminal of the second operational amplifier is adapted to receive the input signal, a second terminal of the second operational amplifier is adapted to receive a reference signal, and an output terminal of the second operational amplifier outputs the adjustment signal; Multiple second adjustment modules, each second adjustment module having a first terminal coupled to a first terminal of a second operational amplifier, a second terminal coupled to the output terminal of the second operational amplifier, and coupled to the control unit; The third adjustment module is coupled to the first terminal of the second operational amplifier and the plurality of second adjustment modules respectively. When any second adjustment module is selected in response to the gating control signal, it provides the gain coefficient and a cutoff frequency adapted to the gain coefficient based on the selected second adjustment module and the third adjustment module.

8. The phase adjustment circuit according to claim 7, characterized in that, Each of the second adjustment modules includes: a third switch, a fourth switch, and a plurality of second adjustment branches coupled between the third switch and the fourth switch, and each of the second adjustment branches includes: a third resistor and a third capacitor; Specifically, for any two second adjustment modules, the third resistor of the second adjustment module with a larger gain coefficient has a larger total resistance but a smaller total capacitance, which is determined by all the third capacitors; and the third and fourth switches of the same second adjustment module are simultaneously turned on or off in response to the gating control signal, while the third and fourth switches of other second adjustment modules are turned off or turned on.

9. The phase adjustment circuit according to claim 1, characterized in that, The control unit is configured to generate a first gating control signal for controlling the gating gain coefficient to be greater than the initial gain coefficient when the amplitude of the adjustment signal is less than the amplitude of the preset signal; and to generate a second gating control signal for controlling the gating gain coefficient to be less than the initial gain coefficient when the amplitude of the adjustment signal is greater than the amplitude of the preset signal.

10. The phase adjustment circuit according to claim 1, characterized in that, The control unit is configured to estimate the strength of the input signal based on the current amplitude of the adjustment signal and the initial gain coefficient, and determine the target gain coefficient according to the amplitude of the preset signal; trigger gain switching control at the phase zero point or silent period of the input signal, select a fixed gain level adjacent to the target gain coefficient, and generate a duty cycle control signal accordingly, and perform high-speed switching between the adjacent fixed gain levels through an analog switch to obtain an equivalent fractional gain; within an adjustment window consisting of multiple modulation cycles, obtain the amplitude of the adjustment signal under the equivalent fractional gain, and adjust the fractional equivalent value according to the deviation between the amplitude of the adjustment signal and the amplitude of the preset signal until the deviation between the amplitude of the adjustment signal and the amplitude of the preset signal is within the target tolerance range.

11. A ranging device, characterized in that, include: The phase adjustment circuit according to any one of claims 1 to 10, the phase adjustment circuit comprising: at least one adjustment unit, and a control unit coupled to the adjustment unit; The transmitting unit is used to transmit signals; A receiving unit is used to receive the echo signal of the transmitted signal; The control unit, coupled to the transmitting unit and the receiving unit respectively, is configured to obtain ranging results based on the transmitted signal and the echo signal; When the adjustment unit is disposed between the control unit and the transmitting unit, the input signal is a driving signal, which is used to drive the transmitting unit to generate the transmitting signal; and / or when the adjustment unit is disposed between the receiving unit and the control unit, the input signal is the echo signal.

12. The ranging device according to claim 11, characterized in that, The ranging device includes a phase-type laser ranging sensor; The transmitting unit includes: one or more laser emitters; The receiving unit includes: one or more detectors; and at least one laser emitter and at least one corresponding detector form a detection channel.

13. A phase adjustment method, characterized in that, include: In response to the relationship between the adjustment signal and the preset signal, a gating control signal is generated; In response to the gating control signal, the gain coefficient of the adjustment unit for adjusting the input signal is changed; wherein the adjustment signal is obtained by the adjustment unit adjusting the input signal according to the initial gain coefficient; and when the adjustment unit has different gain coefficients, the cutoff frequency corresponding to each gain coefficient is the same.

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