Preamplifier circuit and insect detection device

Abstract

This utility model discloses a preamplifier circuit and an insect detection device. The preamplifier circuit, used for insect detection, includes: an input module whose input terminal is connected to the input terminal of the preamplifier circuit; an output terminal of the input module connected to the input terminal of a non-inverting input bias module; and the non-inverting input bias module connected to the non-inverting input terminal of an operational amplifier. A first terminal of an inverting input feedback module is connected to the output terminal of the operational amplifier; a second terminal of the inverting input feedback module is connected to the first terminal of the output module; a third terminal of the inverting input feedback module is connected to the inverting input terminal of the operational amplifier; and a second terminal of the output module is connected to the output terminal of the preamplifier circuit. This preamplifier circuit for insect detection solves the problem of poor signal amplification and feedback stability during insect detection, thus improving the accuracy of insect detection.

Description

Technical Field

[0001] This utility model relates to the field of flying insect detection technology, and in particular to a pre-amplifier circuit and a flying insect detection device. Background Technology

[0002] In the insect detection circuit, insect detection mainly relies on the infrared signal receiver tube outputting current or voltage signals of varying intensities after receiving infrared signals of different strengths. When an insect flies by, the electrical signal received by the infrared signal receiver tube weakens. The infrared signal receiving circuit determines whether an object is blocking the infrared emission signal by detecting the falling or rising edge of the signal and the signal amplitude. If an object blocks the infrared emission signal, the count is incremented by one; otherwise, the count is decremented by one.

[0003] However, in existing technologies, infrared communication relies on the transmission of light signals in the infrared band, which is easily affected by environmental factors such as temperature, humidity, reflective objects, and light sources. Infrared communication technology has a relatively short communication range, and insect detection circuits can experience signal instability and data fluctuations in complex environments. Utility Model Content

[0004] This invention provides a pre-amplifier circuit and a flying insect detection device to solve the problems of unstable electrical signals and frequency response deviation of infrared received electrical signals in current flying insect detection circuits.

[0005] In a first aspect, the present invention provides a pre-amplifier circuit for insect detection, comprising: an input module, a non-inverting input bias module, an inverting input feedback module, an operational amplifier, and an output module;

[0006] The input terminal of the input module is connected to the input terminal of the preamplifier circuit, the output terminal of the input module is connected to the input terminal of the non-inverting input bias module, and the output terminal of the non-inverting input bias module is connected to the non-inverting input terminal of the operational amplifier.

[0007] The first terminal of the inverting input feedback module is connected to the output terminal of the operational amplifier; the second terminal of the inverting input feedback module is connected to the first terminal of the output module; the third terminal of the inverting input feedback module is connected to the inverting input terminal of the operational amplifier; and the second terminal of the output module is connected to the output terminal of the preamplifier circuit.

[0008] The non-inverting input bias module provides a non-inverting bias voltage to the operational amplifier; the inverting input feedback module provides inverting feedback to the operational amplifier.

[0009] Optionally, the input module includes: a first capacitor;

[0010] The first end of the first capacitor is connected to the input end of the input module, and the second end of the first capacitor is connected to the output end of the input module.

[0011] Optionally, the non-inverting input bias module includes: a first resistor;

[0012] The first end of the first resistor is connected to the first power supply, and the second end of the first resistor is connected to the input and output terminals of the non-inverting input bias module.

[0013] The first power supply is used to provide a DC bias voltage for the non-inverting input bias module.

[0014] Optionally, the inverting input feedback module includes: a feedback unit, a compensation unit, and a bias voltage supply unit;

[0015] The first end of the feedback unit is connected to the first end of the inverting input feedback module, the second end of the feedback unit is connected to the first end of the compensation unit, and the third end of the feedback unit is connected to the second end of the compensation unit, the first end of the bias voltage providing unit, and the second end of the inverting input feedback module.

[0016] The second terminal of the bias voltage providing unit is connected to the second power supply.

[0017] The feedback unit is used to provide negative feedback to the operational amplifier; the compensation unit is used to provide inverting compensation to the operational amplifier; and the bias voltage providing unit is used to provide an inverting bias voltage to the operational amplifier.

[0018] Optionally, the feedback unit includes: a second resistor, a third resistor, and a second capacitor;

[0019] The first terminal of the second capacitor is connected to the first terminal of the third resistor and the first terminal of the feedback unit;

[0020] The second end of the third resistor is connected to the first end of the second resistor and the second end of the feedback unit;

[0021] The second terminal of the second capacitor is connected to the second terminal of the second resistor and the third terminal of the feedback unit.

[0022] Optionally, the compensation unit includes: a third capacitor;

[0023] The first end of the third capacitor is connected to the first end of the compensation unit, and the second end of the third capacitor is connected to the second end of the compensation unit.

[0024] Optionally, the bias voltage providing unit includes: a fourth resistor;

[0025] The first end of the fourth resistor is connected to the first end of the bias voltage providing unit, and the second end of the fourth resistor is connected to the second end of the bias voltage providing unit.

[0026] Secondly, this utility model provides a flying insect detection device, including: an infrared signal emitting circuit, an infrared signal emitting tube, an infrared signal receiving tube, and an infrared signal receiving circuit;

[0027] The output terminal of the infrared signal transmitting circuit is connected to the infrared signal transmitting tube, and the input terminal of the infrared signal receiving circuit is connected to the infrared signal receiving tube.

[0028] The infrared signal emitting tube is used to convert the first electrical signal of the infrared signal emitting circuit into an infrared signal and send it to the infrared signal receiving tube. The infrared signal receiving tube is used to convert the received infrared signal into a second electrical signal and transmit it to the infrared signal receiving circuit.

[0029] The infrared signal receiving circuit includes a pre-amplifier circuit in any embodiment of the present invention, which is used to amplify the second electrical signal.

[0030] Optionally, the infrared signal transmitting circuit includes: an infrared signal transmitting power switch circuit and an infrared signal transmitting interface circuit;

[0031] The input terminal of the infrared signal transmitting power switch circuit is connected to the power supply, and the output terminal of the infrared signal transmitting power switch circuit is connected to the input terminal of the infrared signal transmitting interface circuit.

[0032] The infrared signal transmitting power switch circuit is used to control the power on and power off of the infrared signal transmitting circuit; the infrared signal transmitting interface circuit is used to connect the infrared signal transmitting tube.

[0033] Optionally, the infrared signal receiving circuit further includes: an infrared signal receiving and processing circuit and a signal bandpass filter circuit;

[0034] The output terminal of the infrared signal receiving and processing circuit is connected to the input terminal of the preamplifier circuit, and the output terminal of the preamplifier circuit is connected to the input terminal of the signal bandpass filter circuit.

[0035] The infrared signal receiving and processing circuit is used to filter and stabilize the second electrical signal; the signal bandpass filter circuit is used to perform bandpass filtering on the second electrical signal.

[0036] This utility model discloses a pre-amplifier circuit and an insect detection device. The pre-amplifier circuit includes: an input module connected to a non-inverting input bias module, which transmits the received signal to the bias module for processing. The processed signal from the non-inverting input bias module is then fed into the non-inverting input of an operational amplifier. An inverting input feedback module is connected to the operational amplifier and the output module through its multiple ports, forming a feedback loop. The output module receives the signal from the inverting input feedback module and uses it as the final output of the circuit. This pre-amplifier circuit, applied in an insect detection system, processes the weak electrical signal generated by insects blocking infrared signals, thus solving the problems of poor signal amplification and feedback stability during insect detection and improving the accuracy of insect detection. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the structure of a preamplifier circuit provided in an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of another preamplifier circuit provided in this embodiment of the present invention;

[0040] Figure 3 This is a circuit diagram of an inverting input feedback module provided in an embodiment of the present invention;

[0041] Figure 4 This is a schematic diagram of the structure of a flying insect detection device provided in an embodiment of the present invention;

[0042] Figure 5 This is a schematic diagram of the structure of an infrared signal transmitting circuit provided in an embodiment of the present invention;

[0043] Figure 6 This is a schematic diagram of the structure of an infrared signal receiving circuit provided in an embodiment of the present invention;

[0044] Figure 7 This is a circuit diagram of an infrared signal transmitting circuit provided in an embodiment of the present invention;

[0045] Figure 8 This is a circuit diagram of an infrared signal receiving circuit provided in an embodiment of the present invention. Detailed Implementation

[0046] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0047] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0048] Figure 1 This is a schematic diagram of a preamplifier circuit provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the preamplifier circuit includes: an input module 101, a non-inverting input bias module 102, an inverting input feedback module 104, an operational amplifier 103, and an output module 105. The input terminal of the input module 101 is connected to the input terminal of the preamplifier circuit, and the output terminal of the input module 101 is connected to the input terminal of the non-inverting input bias module 102. The non-inverting input bias module 102 is connected to the non-inverting input terminal of the operational amplifier 103. The first terminal of the inverting input feedback module 104 is connected to the output terminal of the operational amplifier 103, the second terminal of the inverting input feedback module 104 is connected to the first terminal of the output module 105, and the third terminal of the inverting input feedback module 104 is connected to the inverting input terminal of the operational amplifier 103. The second terminal of the output module 105 is connected to the output terminal of the preamplifier circuit. The non-inverting input bias module 102 provides a non-inverting bias voltage to the operational amplifier 103. The inverting input feedback module 104 provides inverting feedback to the operational amplifier 103.

[0049] Specifically, input module 101 is located at the starting input terminal of the preamplifier circuit to process the input signal. For example, input module 101 includes a capacitor to receive the output signal from the infrared signal receiver, with its first end connected to the input terminal of the preamplifier circuit and its second end connected to the input terminal of the non-inverting input bias module 102. The capacitor isolates the DC component in the input signal, allowing only AC signals to enter the amplifier circuit and preventing DC bias interference. Alternatively, input module 101 can use a resistor as an input element, with one end serving as the circuit's input and the other end connected to the non-inverting input bias module. The resistor in input module 101 limits the input current, protecting the circuit from excessive input current. Non-inverting input bias module 102 provides a non-inverting bias voltage to operational amplifier 103 to ensure stable operation even with zero input. The non-inverting bias voltage provided by non-inverting input bias module 102 helps enhance circuit stability. In operational amplifier 103, the non-inverting bias voltage can also cancel out a portion of the DC component of the input signal, thereby preventing overload or saturation when processing DC signals. By providing a stable non-inverting bias voltage, the operational amplifier can process the input signal more accurately, reducing errors caused by input signal fluctuations or offsets. For example, the non-inverting input bias module 102 consists of a resistor and a power supply. One end of the resistor is connected to the non-inverting input of the operational amplifier, and the other end is connected to the power supply. The power supply provides a stable non-inverting bias voltage to the operational amplifier through the resistor, ensuring stable operation even with zero input. Operational amplifier 103 provides a stable non-inverting bias voltage to ensure the signal operates in the linear region during amplification. The inverting input feedback module 104 provides inverting feedback to operational amplifier 103. As a negative feedback network, the inverting input feedback module 104 sets the closed-loop gain of the amplifier circuit. Simultaneously, the inverting input feedback module 104 suppresses high-frequency noise, improves circuit stability, stabilizes the output of operational amplifier 103, and prevents self-oscillation. For example, the inverting input feedback module 104 can be configured with two resistors and one capacitor. The two resistors form negative feedback, and the capacitor suppresses high-frequency noise and improves circuit stability. The input terminal of the output module 105 is connected to the output terminal of the operational amplifier 103, and the output terminal is connected to the output terminal of the preamplifier circuit. The signal processed by the operational amplifier 103 is transmitted to the subsequent circuit through the output module 105. For example, the output module 105 includes a resistor, and the output module limits the signal current output by the preamplifier circuit to protect the subsequent circuit.

[0050] When the input signal enters the circuit through the input module 101, the non-inverting input bias module 102 provides a stable non-inverting bias voltage to the operational amplifier 103. The operational amplifier 103 amplifies the input electrical signal. Simultaneously, the inverting input feedback module 104 feeds back a portion of the output signal to the inverting input of the operational amplifier through a negative feedback loop to adjust the amplification factor and ensure circuit stability. Finally, the amplified signal is output to the subsequent processing circuit through the output module 105. The input signal includes a weak electrical signal generated by an insect blocking the infrared signal.

[0051] This utility model embodiment provides a pre-amplifier circuit, wherein the input module is connected to the non-inverting input bias module, transmitting the received signal to the bias module for processing. The signal processed by the non-inverting input bias module is sent to the non-inverting input of the operational amplifier. The inverting input feedback module is connected to the operational amplifier and the output module through its multiple ports, forming a feedback loop. The output module receives the signal from the inverting input feedback module and uses it as the final output of the circuit. This pre-amplifier circuit is applied to an insect detection system, processing the weak electrical signal generated by insects blocking infrared signals to solve the problems of poor electrical signal amplification and feedback stability during insect detection, thereby improving the accuracy of insect detection.

[0052] Based on the above embodiments, the input module 101 includes: a first capacitor; a first end of the first capacitor is connected to the input end of the input module 101, and a second end of the first capacitor is connected to the output end of the input module 101.

[0053] Specifically, input module 101 is a first capacitor. This first capacitor has filtering characteristics, capable of removing high-frequency noise or unwanted high-frequency components from the input signal. The first capacitor performs preliminary filtering of the input signal. Simultaneously, if the input signal of the preamplifier circuit contains a DC component, the first capacitor can isolate the DC component, allowing only AC signals to pass. This allows the operational amplifier to focus on processing AC signals, avoiding the influence of DC components on the amplification effect. The first capacitor can also be used for signal coupling, coupling the output signal of the preceding stage circuit to the input terminal of the following stage circuit. This helps ensure smooth signal transmission between different circuit modules. Furthermore, due to the first capacitor's characteristic of isolating DC components and allowing only AC signals to pass, it can prevent the preamplifier circuit from being affected by DC levels.

[0054] Optionally, the non-inverting input bias module 102 includes: a first resistor; a first end of the first resistor is connected to a first power supply, and a second end of the first resistor is connected to the input and output terminals of the non-inverting input bias module 102; the first power supply is used to provide a DC bias voltage for the non-inverting input bias module 102.

[0055] Specifically, the combination of the first resistor and the first power supply provides a stable in-phase bias voltage for the operational amplifier. This in-phase bias voltage ensures that the operational amplifier maintains a stable operating point when processing input signals.

[0056] The preamplifier circuit provided in this embodiment includes an input module, a non-inverting input bias module, an inverting input feedback module, an operational amplifier, and an output module. The input module includes a first capacitor connected across its two ends for filtering and isolating DC signals from the input signal. The non-inverting input bias module includes a first resistor connected to a first power supply, providing a stable non-inverting bias voltage for the operational amplifier. In this embodiment, the first capacitor in the input module isolates DC signals, allowing only AC signals to pass through, thus preventing the influence of DC components on the amplification effect. The first resistor in the non-inverting input bias module provides a stable bias voltage, ensuring that the operational amplifier maintains a stable operating point when processing the input signal, improving circuit stability and amplification accuracy.

[0057] Based on the above embodiments, Figure 2 This is a schematic diagram of another preamplifier circuit provided in this embodiment of the present invention, as shown below. Figure 2 As shown, the inverting input feedback module 104 includes: a feedback unit 1041, a compensation unit 1042, and a bias voltage providing unit 1043; the first terminal of the feedback unit 1041 is connected to the first terminal of the inverting input feedback module 104, the second terminal of the feedback unit 1041 is connected to the first terminal of the compensation unit 1042, and the third terminal of the feedback unit 1041 is connected to the second terminal of the compensation unit 1042, the first terminal of the bias voltage providing unit 1043, and the second terminal of the inverting input feedback module 104; the second terminal of the bias voltage providing unit 1043 is connected to a second power supply; the feedback unit 1041 is used to provide negative feedback to the operational amplifier 103; the compensation unit 1042 is used to perform inverting compensation on the operational amplifier 103; and the bias voltage providing unit 1043 is used to provide an inverting bias voltage to the operational amplifier 103.

[0058] Specifically, the first terminal of feedback unit 1041 is connected to the output terminal of operational amplifier, the second terminal is connected to the first terminal of compensation unit 1042, and the third terminal is connected to the second terminal of compensation unit 1042, the first terminal of bias voltage providing unit 1043, and the second terminal of inverting input feedback module 104. Feedback unit 1041 provides negative feedback to operational amplifier 103. Negative feedback helps stabilize the output of operational amplifier, reduces distortion, and the amplifier gain can be changed by adjusting the feedback amount. In applications involving insect detection, the feedback unit 1041 helps ensure the stability and accuracy of signal amplification in the preamplifier circuit.

[0059] The compensation unit 1042 is connected to the second and third terminals of the feedback unit 1041 and is used to perform inverse compensation on the operational amplifier 103. Phase distortion or nonlinear distortion can occur in operational amplifiers. The compensation unit introduces a compensation signal opposite to the distortion to cancel or balance these distortions, thereby improving the amplifier's performance.

[0060] The first terminal of the bias voltage providing unit 1043 is connected to the third terminal of the feedback unit 1041, and the second terminal is connected to the second power supply. The main function of the bias voltage providing unit 1043 is to provide an inverting bias voltage to the operational amplifier 103. The inverting bias voltage can adjust the input or output characteristics of the operational amplifier, helping to ensure that the operational amplifier can correctly amplify and process the input signal.

[0061] In the preamplifier circuit provided in this embodiment of the invention, the inverting input feedback module provides negative feedback to the operational amplifier through the feedback unit to stabilize its output, the compensation unit performs inverting compensation to cancel distortion, and the bias voltage providing unit provides an inverting bias voltage to adjust the characteristics of the operational amplifier. In the preamplifier circuit provided in this embodiment of the invention, the inverting input feedback module improves the stability and performance of the operational amplifier, reduces distortion, and provides more accurate and reliable signal amplification support for applications such as insect detection.

[0062] Based on the above embodiments, Figure 3 This is a circuit diagram of an inverting input feedback module provided in an embodiment of this utility model, as shown below. Figure 3 As shown, in the inverting input feedback module, the feedback unit 1041 includes: a second resistor R2, a third resistor R3, and a second capacitor C2; the first end of the second capacitor C2 is connected to the first end of the third resistor R3 and the first end of the feedback unit 1041; the second end of the third resistor R3 is connected to the first end of the second resistor R2 and the second end of the feedback unit 1041; the second end of the second capacitor C2 is connected to the second end of the second resistor R2 and the third end of the feedback unit 1041.

[0063] The compensation unit 1042 includes: a third capacitor C3; the first end of the third capacitor C3 is connected to the first end of the compensation unit 1042, and the second end of the third capacitor C3 is connected to the second end of the compensation unit 1042.

[0064] The bias voltage providing unit 1043 includes: a fourth resistor R4; the first end of the fourth resistor R4 is connected to the first end of the bias voltage providing unit 1043, and the second end of the fourth resistor R4 is connected to the second end of the bias voltage providing unit 1043.

[0065] Specifically, such as Figure 3As shown, in the feedback unit 1041, the second resistor R2 and the third resistor R3 function as current limiters and voltage dividers, limiting the current through the feedback path and preventing excessive current from damaging components or causing circuit instability. Simultaneously, the second resistor R2 and the third resistor R3 work together to adjust the strength and stability of the feedback signal, reducing its voltage to a level suitable for operational amplifier processing, ensuring the effectiveness of the feedback signal. The second capacitor C2 primarily functions as a filter and energy storage unit, removing high-frequency noise or unwanted high-frequency components from the feedback signal. Furthermore, the capacitor provides a stable voltage or current when the signal changes, improving the stability and reliability of the circuit.

[0066] In compensation unit 1042, the first terminal of the third capacitor C3 is connected to the first terminal of compensation unit 1042, and the second terminal is connected to the second terminal of compensation unit 1042. In compensation unit 1042, the third capacitor C3 can remove high-frequency noise or unwanted high-frequency components from the operational amplifier output signal, thereby improving signal purity and stability. Simultaneously, the energy storage characteristics of the third capacitor C3 can provide a stable voltage or current when the signal changes, helping the compensation unit to perform more accurate inversion compensation of the operational amplifier, improving the overall performance and stability of the circuit.

[0067] In the bias voltage providing unit 1043, the fourth resistor R4 is connected between the second power supply VCC2 and the inverting input of the operational amplifier. In the bias voltage providing unit 1043, the fourth resistor R4 may be used for voltage division, reducing the second power supply VCC2 to a voltage level suitable for operational amplifier bias. Simultaneously, it can also limit the current through the bias voltage providing unit, protecting circuit components from excessive current from the second power supply VCC2.

[0068] Based on the above embodiments, Figure 4 This is a schematic diagram of the structure of a flying insect detection device provided in an embodiment of this utility model, as shown below. Figure 4 As shown, the flying insect detection device includes: an infrared signal emitting circuit 201, an infrared signal emitting tube 202, an infrared signal receiving tube 203, and an infrared signal receiving circuit 204; the output terminal of the infrared signal emitting circuit 201 is connected to the infrared signal emitting tube 202, and the input terminal of the infrared signal receiving circuit 204 is connected to the infrared signal receiving tube 203; the infrared signal emitting tube 202 is used to convert the first electrical signal of the infrared signal emitting circuit 201 into an infrared signal and send it to the infrared signal receiving tube 203, and the infrared signal receiving tube 203 is used to convert the received infrared signal into a second electrical signal and transmit it to the infrared signal receiving circuit 204; the infrared signal receiving circuit 204 includes a pre-amplifier circuit in any embodiment of the present invention, which amplifies the second electrical signal.

[0069] Specifically, such as Figure 1-4 As shown, the infrared signal emitting circuit 201 generates a first electrical signal, and the infrared signal emitting tube 202 receives the electrical signal from the infrared signal emitting circuit 201 and converts it into an infrared signal. Infrared signals have strong penetrating power and are not easily interfered with by ambient light, making them suitable for detecting small moving objects such as flying insects. The infrared signal receiving tube 203 is responsible for receiving the infrared signals reflected or scattered by the flying insects. When a flying insect flies over the detection area, it reflects or scatters the infrared signal emitted by the infrared signal receiving tube 203. The infrared signal received by the infrared signal receiving tube 203 is converted into a second electrical signal and transmitted to the infrared signal receiving circuit 204 for further processing.

[0070] The infrared signal receiving circuit 204 includes a preamplifier circuit. In any embodiment of this invention, the preamplifier circuit amplifies the received second electrical signal to improve its strength and stability. The preamplifier circuit includes an input module 101, a non-inverting input bias module 102, an inverting input feedback module 104, an operational amplifier 103, and an output module 105, thereby achieving precise amplification of the electrical signal.

[0071] For example, when the insect detection device is activated, the infrared signal emitting circuit 201 starts working, and the first electrical signal of the infrared signal emitting circuit 201 drives the infrared signal emitting tube 202 to emit an infrared signal. The infrared signal propagates in space and is reflected or scattered when it encounters moving objects such as flying insects. The infrared signal is converted into a second electrical signal by the infrared signal receiving tube 203 and then transmitted to the infrared signal receiving circuit 204. The infrared signal receiving circuit 204 amplifies the second electrical signal. By detecting the rising or falling edge of the processed electrical signal, the reflection or scattering of the infrared signal can be detected, thereby enabling the detection of flying insects.

[0072] In the insect detection device provided in this embodiment of the invention, an infrared signal emitting circuit generates a first electrical signal to drive an infrared signal emitting tube. The infrared signal emitting tube receives the electrical signal from the infrared signal emitting circuit and converts it into an infrared signal for transmission. An infrared signal receiving tube receives the infrared signal and converts it into a second electrical signal. The infrared signal receiving circuit includes a pre-amplifier circuit for amplifying the received second electrical signal. In the insect detection device provided in this embodiment of the invention, the pre-amplifier circuit amplifies the received electrical signal, enabling the insect detection device to more sensitively detect the presence of insects. Even if the insect moves quickly or is far away, it can still be effectively detected. This solves the problem of poor electrical signal amplification and feedback stability during insect detection, thus improving the accuracy of insect detection.

[0073] Based on the above embodiments, Figure 5 This is a schematic diagram of the structure of an infrared signal transmitting circuit provided in an embodiment of the present invention. Figure 6 This is a schematic diagram of the structure of an infrared signal receiving circuit provided in an embodiment of the present invention, as shown below. Figure 5 and Figure 6 As shown, the infrared signal transmitting circuit 201 includes: an infrared signal transmitting power switch circuit 301 and an infrared signal transmitting interface circuit 302; the input terminal of the infrared signal transmitting power switch circuit 301 is connected to the power supply, and the output terminal of the infrared signal transmitting power switch circuit 301 is connected to the input terminal of the infrared signal transmitting interface circuit 302; the infrared signal transmitting power switch circuit 301 is used to control the power on and power off of the infrared signal transmitting circuit 201; the infrared signal transmitting interface circuit 302 is used to connect the infrared signal transmitting tube.

[0074] The infrared signal receiving circuit 204 further includes an infrared signal receiving and processing circuit 402 and a signal bandpass filter circuit 403; the output terminal of the infrared signal receiving and processing circuit 402 is connected to the input terminal of the preamplifier circuit 401, and the output terminal of the preamplifier circuit 401 is connected to the input terminal of the signal bandpass filter circuit 403; the infrared signal receiving and processing circuit 402 is used to filter and regulate the second electrical signal; the signal bandpass filter circuit 403 is used to perform bandpass filtering on the second electrical signal.

[0075] Specifically, such as Figure 5 As shown, the infrared signal transmitting power switch circuit 301 is used to control the power on and off of the infrared signal transmitting circuit 201. When it is necessary to transmit an infrared signal, the infrared signal transmitting power switch circuit 301 allows current to flow, thereby starting the infrared signal transmission process; when it is not necessary to transmit an infrared signal, the infrared signal transmitting power switch circuit 301 will cut off the current to save energy and extend the service life of the circuit components.

[0076] An infrared signal transmitting interface circuit 302 is connected in series between the power supply and the infrared signal transmitting tube for connecting the infrared signal transmitting tube. Exemplarily, it includes an infrared signal transmitting tube base and a current-limiting resistor. The current-limiting resistor limits the current, and the infrared signal transmitting tube base is used to connect the infrared signal transmitting tube.

[0077] like Figure 6As shown, the input terminal of the infrared signal receiving and processing circuit 402 is connected to the infrared signal receiving tube 203, and is responsible for receiving the second electrical signal converted by the infrared signal receiving tube. Its output terminal is connected to the input terminal of the preamplifier circuit 401. The main function of the infrared signal receiving and processing circuit 402 is to acquire the second electrical signal converted by the infrared signal receiving tube based on the infrared signal. For example, the infrared signal receiving and processing circuit 402 also includes a voltage regulation and filtering module to filter and regulate the received second electrical signal. Filtering can remove noise and interference components in the signal; voltage regulation ensures that the signal remains stable during transmission and avoids affecting the accuracy of the signal due to voltage fluctuations. The function of the preamplifier circuit 401 is to amplify the received second electrical signal, and includes the features and beneficial effects of the preamplifier circuit 401 in any of the above embodiments, which will not be elaborated here. The input terminal of the bandpass filter circuit 403 is connected to the output terminal of the preamplifier circuit 401, and the bandpass filter circuit 403 is used to perform bandpass filtering on the amplified second electrical signal. Bandpass filtering can selectively allow signals within a certain frequency range to pass through while blocking signals of other frequencies, which helps reduce noise and interference.

[0078] Based on the above embodiments, Figure 7 This is a circuit diagram of an infrared signal transmitting circuit provided in an embodiment of the present invention. Figure 8 This is a circuit diagram of an infrared signal receiving circuit provided in an embodiment of this utility model, as shown below. Figure 7 As shown: In the infrared signal transmitting power supply switch circuit 301, the third power supply VCC3 is connected to the first terminal of the sixth resistor R6 and the source of the first field-effect transistor Q1; the drain of the first field-effect transistor Q1 is connected to the first terminal of the fourth capacitor C4; the second terminal of the sixth resistor R6, the gate of the first field-effect transistor Q1, and the second terminal of the fourth capacitor C4 are connected; the gate of the first field-effect transistor Q1 is connected to the drain of the second field-effect transistor Q2; the gate of the second field-effect transistor Q2 is connected to the first terminal of the seventh resistor R7. The source of the second field-effect transistor Q2 is connected to the first terminal of the eighth resistor R8, and the second terminal of the eighth resistor R8 is grounded; the second terminal of the seventh resistor R7 is connected to the first terminal of the ninth resistor R9 and the PWM modulation signal P1; the second terminal of the ninth resistor R9 is grounded.

[0079] The infrared signal transmitting interface circuit 302 includes a tenth resistor R10 and a first infrared signal emitting tube base J1. The first terminal of the fourth capacitor C4 is connected to the first terminal of the tenth resistor R10, and the second terminal of the tenth resistor R10 is connected to the first terminal of the first infrared signal emitting tube base J1. The second terminal of the first infrared signal emitting tube base J1 is grounded. The first infrared signal emitting tube base J1 is used to mount the infrared signal emitting tube.

[0080] Specifically, when the PWM modulation signal P1 is high, the second field-effect transistor Q2 is turned on, and its drain voltage is pulled low. This causes the gate voltage of the first field-effect transistor Q1 to be lower than its source voltage, turning on Q1. Current flows from the third power supply VCC3 through Q1 to the infrared emission interface circuit. When the PWM modulation signal P1 is low, the second field-effect transistor Q2 is turned off, and the gate voltage of the first field-effect transistor Q1 approaches VCC3, turning off Q1 and stopping power supply. In the infrared signal emission power supply switching circuit of this embodiment, the switching frequency of the first field-effect transistor Q1 is controlled by the PWM modulation signal P1 to adjust the luminous intensity or pulse frequency of the infrared signal emitting diode.

[0081] Optionally, in the infrared signal transmitting power supply switch circuit 301, the first field-effect transistor Q1 is a P-channel depletion-type MOSFET, the second field-effect transistor Q2 is an N-channel depletion-type MOSFET; the third power supply VCC3 has a voltage of 3.3V; the sixth resistor R6 has a resistance of 100KΩ; the fourth capacitor C4 has a capacitance of 0.1uF; the seventh resistor has a resistance of 4.7KΩ; the eighth resistor R8 has a resistance of 10KΩ; and the ninth resistor R9 has a resistance of 100KΩ.

[0082] like Figure 8 As shown, in the infrared signal receiving circuit 402, the second terminal of the second infrared signal emitting tube base J2 is grounded. The first terminal of the twelfth resistor R12, the first terminal of the second infrared signal emitting tube base J2, and the first terminal of the thirteenth resistor R13 are connected; the second terminal of the twelfth resistor R12 is connected to the fourth power supply VCC4; the second terminal of the thirteenth resistor R13 serves as the output terminal of the infrared signal receiving circuit.

[0083] In the preamplifier circuit 401, the first terminal of the first capacitor C1 serves as the input terminal of the preamplifier circuit. The second terminal of the first capacitor C1 is connected to the first terminal of the first resistor R1 and the non-inverting input terminal of the operational amplifier U1. The second terminal of the first resistor R1 is connected to the first power supply VCC1. The first terminals of the second capacitor C2, the fourth resistor R4, the second resistor R2, and the third capacitor C3 are connected to the inverting input terminal of the operational amplifier U1. The second terminal of the fourth resistor R4 is connected to the second power supply VCC2. The second terminal of the second capacitor C2, the first terminal of the third resistor R3, and the output terminal of the operational amplifier U1 are connected. The second terminal of the second resistor R2, the second terminal of the third capacitor C3, the second terminal of the third resistor R3, and the first terminal of the fifth resistor R5 are connected. The second terminal of the fifth resistor R5 serves as the output terminal of the preamplifier circuit.

[0084] In the signal bandpass filter circuit 403, the first terminal of the fifth capacitor C5 serves as the input terminal of the signal bandpass filter circuit; the second terminal of the fifth capacitor C5 is connected to the first terminal of the sixth capacitor C6 and the first terminal of the fourteenth resistor R14; the second terminal of the sixth capacitor C6 is connected to the first terminal of the fifteenth resistor R15 and the non-inverting input terminal of the second operational amplifier U2; the second terminal of the fifteenth resistor R15 is connected to the fifth power supply VCC5. The second terminal of the fourteenth resistor R14 is connected to the output terminal and the inverting input terminal of the second operational amplifier U2, and the first terminal of the sixteenth resistor R16; the second terminal of the sixteenth resistor R16 is connected to the first terminal of the seventh capacitor C7 and the first terminal of the seventeenth resistor R17; the second terminal of the seventeenth resistor R17 is connected to the first terminal of the eighth capacitor C8 and the non-inverting input terminal of the third operational amplifier U3; the second terminal of the eighth capacitor C8 is grounded; the second terminal of the seventh capacitor C7 is connected to the output terminal and the inverting input terminal of the third operational amplifier U3, and the output terminal of the third operational amplifier U3 serves as the output terminal of the signal bandpass filter circuit.

[0085] Specifically, in the infrared signal receiving circuit 402, the infrared signal receiving tube is installed on the base J2 of the second infrared signal emitting tube. After the infrared signal receiving tube detects the infrared light signal, it generates a current signal proportional to the light intensity and outputs it to the preamplifier circuit 401.

[0086] In the preamplifier circuit 401, the first terminal of the first capacitor C1 receives the signal, and the second terminal is connected to the first resistor R1 and the non-inverting input of the operational amplifier U1. The first resistor R1 is connected to the first power supply VCC1, providing a reference voltage for the non-inverting input of the operational amplifier U1. The inverting input of the operational amplifier U1 is connected to the second capacitor C2, the fourth resistor R4, the second resistor R2, and the third capacitor C3. The output terminal forms a feedback loop through the third resistor R3, the second resistor R2, and the third capacitor C3. In the feedback network, the fourth resistor R4 is used to provide an inverting bias voltage for the operational amplifier.

[0087] The signal bandpass filter circuit 403 includes high-pass and low-pass filters. Resistor R14 (fourteenth), capacitor C6 (sixth), resistor R15 (fifteenth), and operational amplifier U2 filter out low-frequency noise, allowing only signals above 21Hz to pass. Capacitor C8 (eighth), resistor R17 (seventeenth), and capacitor C7 (seventh) filter out high-frequency noise, retaining only signals below 5kHz. The two-stage filtering combination forms a bandpass characteristic of 21Hz-5kHz, focusing signals related to insect activity.

[0088] Optionally, in the infrared signal receiving circuit 402, the resistance of the twelfth resistor R12 is 1KΩ.

[0089] In the preamplifier circuit 401, the capacitance of the first capacitor C1 is 0.1uF; the capacitance of the second capacitor C2 is 10pF; the capacitance of the third capacitor C3 is 1nF; the resistance of the first resistor R1 is 100KΩ; the resistance of the second resistor R2 is 100KΩ; and the resistance of the fourth resistor R4 is 1Ω.

[0090] In the signal bandpass filter circuit 403, the capacitance of the fifth capacitor C5 is 33nF; the capacitance of the sixth capacitor C6 is 33nF; the capacitance of the seventh capacitor C7 is 3.9nF; the capacitance of the eighth capacitor C8 is 2nF; the resistance of the fourteenth resistor R14 is 160KΩ; the resistance of the fifteenth resistor R15 is 324KΩ; the resistance of the sixteenth resistor R16 is 10KΩ; and the resistance of the seventeenth resistor R17 is 10KΩ.

[0091] In the insect detection device provided in this embodiment of the invention, the infrared signal transmitting power switch circuit is connected to the infrared signal transmitting interface circuit in the infrared signal transmitting circuit. The infrared signal transmitting power switch circuit controls the power switch of the infrared signal transmitting tube connected in the infrared signal transmitting interface circuit. The infrared signal receiving circuit includes an infrared signal receiving and processing circuit, a pre-amplifier circuit, a bandpass filter circuit, and a processed signal output circuit. The output terminal of the infrared signal receiving circuit is connected to the input terminal of the pre-amplifier circuit, the output terminal of the pre-amplifier circuit is connected to the input terminal of the bandpass filter circuit, and the output terminal of the bandpass filter circuit is connected to the input terminal of the processed signal output circuit. In the insect detection device provided in this embodiment of the invention, the use of a pre-amplifier circuit to acquire signals achieves a small frequency response deviation. The use of a multi-stage filter circuit in the bandpass filter circuit results in a more stable transmitted signal and better equipment uniformity compared to a traditional single-stage filter circuit. The use of a 21Hz to 5KHz bandpass filter provides stronger anti-interference capability compared to traditional low-pass filters. The insect detection device provided in this embodiment of the invention improves the accuracy of insect detection.

[0092] It should be understood that the various forms of the process shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this utility model can be achieved, and this is not limited herein.

[0093] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A pre-signal amplification circuit, characterized by, The preamplifier circuit is used for insect detection and includes: an input module, a non-inverting input bias module, an inverting input feedback module, an operational amplifier, and an output module. The input terminal of the input module is connected to the input terminal of the preamplifier circuit, the output terminal of the input module is connected to the input terminal of the non-inverting input bias module, and the output terminal of the non-inverting input bias module is connected to the non-inverting input terminal of the operational amplifier. The first terminal of the inverting input feedback module is connected to the output terminal of the operational amplifier; the second terminal of the inverting input feedback module is connected to the first terminal of the output module; the third terminal of the inverting input feedback module is connected to the inverting input terminal of the operational amplifier; and the second terminal of the output module is connected to the output terminal of the preamplifier circuit. The non-inverting input bias module provides a non-inverting bias voltage to the operational amplifier; the inverting input feedback module provides inverting feedback to the operational amplifier.

2. The pre-signal amplification circuit according to claim 1, characterized in that, The input module includes: a first capacitor; The first end of the first capacitor is connected to the input end of the input module, and the second end of the first capacitor is connected to the output end of the input module.

3. The pre-signal amplification circuit according to claim 1, wherein, The in-phase input bias module includes: a first resistor; The first end of the first resistor is connected to the first power supply, and the second end of the first resistor is connected to the input and output terminals of the non-inverting input bias module. The first power supply is used to provide a DC bias voltage for the non-inverting input bias module.

4. The pre-signal amplification circuit according to claim 1, wherein, The inverting input feedback module includes: a feedback unit, a compensation unit, and a bias voltage supply unit; The first end of the feedback unit is connected to the first end of the inverting input feedback module, the second end of the feedback unit is connected to the first end of the compensation unit, and the third end of the feedback unit is connected to the second end of the compensation unit, the first end of the bias voltage providing unit, and the second end of the inverting input feedback module. The second terminal of the bias voltage providing unit is connected to the second power supply. The feedback unit is used to provide negative feedback to the operational amplifier; the compensation unit is used to provide inverting compensation to the operational amplifier; and the bias voltage providing unit is used to provide an inverting bias voltage to the operational amplifier.

5. The pre-signal amplification circuit according to claim 4, characterized in that, The feedback unit includes: a second resistor, a third resistor, and a second capacitor; The first terminal of the second capacitor is connected to the first terminal of the third resistor and the first terminal of the feedback unit; The second end of the third resistor is connected to the first end of the second resistor and the second end of the feedback unit; The second terminal of the second capacitor is connected to the second terminal of the second resistor and the third terminal of the feedback unit.

6. The pre-signal amplification circuit according to claim 4, wherein, The compensation unit includes: a third capacitor; The first end of the third capacitor is connected to the first end of the compensation unit, and the second end of the third capacitor is connected to the second end of the compensation unit.

7. The pre-signal amplification circuit according to claim 4, wherein The bias voltage providing unit includes: a fourth resistor; The first end of the fourth resistor is connected to the first end of the bias voltage providing unit, and the second end of the fourth resistor is connected to the second end of the bias voltage providing unit.

8. A flying insect detection apparatus, characterized by, include: Infrared signal transmitting circuit, infrared signal transmitting tube, infrared signal receiving tube, and infrared signal receiving circuit; The output terminal of the infrared signal transmitting circuit is connected to the infrared signal transmitting tube, and the input terminal of the infrared signal receiving circuit is connected to the infrared signal receiving tube. The infrared signal emitting tube is used to convert the first electrical signal of the infrared signal emitting circuit into an infrared signal and send it to the infrared signal receiving tube. The infrared signal receiving tube is used to convert the received infrared signal into a second electrical signal and transmit it to the infrared signal receiving circuit. The infrared signal receiving circuit includes a preamplifier circuit according to any one of claims 1-7, wherein the preamplifier circuit is used to amplify the second electrical signal.

9. The flying insect detection apparatus of claim 8, wherein, The infrared signal transmitting circuit includes: an infrared signal transmitting power switch circuit and an infrared signal transmitting interface circuit; The input terminal of the infrared signal transmitting power switch circuit is connected to the power supply, and the output terminal of the infrared signal transmitting power switch circuit is connected to the input terminal of the infrared signal transmitting interface circuit. The infrared signal transmitting power switch circuit is used to control the power on and power off of the infrared signal transmitting circuit; the infrared signal transmitting interface circuit is used to connect the infrared signal transmitting tube.

10. The flying insect detection apparatus of claim 8, wherein, The infrared signal receiving circuit further includes: an infrared signal receiving and processing circuit and a signal bandpass filter circuit; The output terminal of the infrared signal receiving and processing circuit is connected to the input terminal of the preamplifier circuit, and the output terminal of the preamplifier circuit is connected to the input terminal of the bandpass filter circuit. The infrared signal receiving and processing circuit is used to filter and stabilize the second electrical signal; the signal bandpass filter circuit is used to perform bandpass filtering on the second electrical signal.

Images