A High Reliability Microwave Signal Detection Circuit

Abstract

The present invention provides a highly reliable microwave signal detection circuit, comprising a signal input port, a DC power supply port, a ground port, an output port, a coupling module, a detection module, a reference voltage module, a voltage comparison module, a first resistor, a second resistor, a first inductor, and a second inductor. The present invention improves the accuracy of the comparison point voltage and the sensitivity of the detection diode by adding two choke inductors to the input voltage divider end and using eutectic welding in the welding process of the component structure, thereby improving the dynamic detection range and reliability of the product.

Description

Technical Field

[0001] The invention relates to the field of signal processing, in particular to a high-reliability microwave signal detection circuit. Background Art

[0002] The RF signal is a high-frequency signal. The microwave signal detection circuit can be used to detect the amplitude of the RF signal. When the input level is within the specified range, the output level is a TTL low level. When the input level exceeds the specified range, the output TTL level flips, thereby making a detection indication. Due to the small size of the substrate of the RF product, the RF signal is easy to couple or crosstalk, thereby interfering with the comparison point voltage at the negative input end of the comparator in the microwave signal detection circuit, affecting the detection result. According to the existing microwave detection circuit topology, when the input power is small, the RF signal will couple to the negative input end of the voltage comparator. When the input power is large, the detection voltage may affect the comparison point voltage. The existing structure of the voltage comparator input end is difficult to detect due to the interference of the RF signal and the fluctuation. At the same time, it is also impossible to effectively prevent the RF signal from coupling and crosstalk, thereby affecting the reliability of the detection circuit. Summary of the invention

[0003] In order to solve the above problems, the present invention proposes a highly reliable microwave signal detection circuit, which improves the accuracy of the comparison point voltage and the sensitivity of the detection diode by adding two choke inductors at the input voltage divider end and using eutectic welding in the component structure welding process, thereby improving the dynamic detection range and reliability of the product.

[0004] The present invention is achieved through the following technical solutions:

[0005] The present invention provides a highly reliable microwave signal detection circuit, comprising:

[0006] Signal input port, used to access radio frequency signals;

[0007] DC power port, used to connect to an external DC power supply;

[0008] Ground port, used for power supply and signal grounding;

[0009] A coupling module, a first end of which is connected to the signal input port and is used for coupling input of a radio frequency signal;

[0010] A detection module, a first end of which is connected to the second end of the coupling module, for detecting and acquiring a detection voltage signal;

[0011] A reference voltage module, connected to the DC power port and the ground port respectively for generating a reference voltage;

[0012] A voltage comparison module, whose input end is respectively connected to the second end of the detection module and the output end of the reference voltage module, and is used to compare the detection voltage signal with the reference voltage;

[0013] an output port, connected to the voltage comparison module, for outputting a voltage comparison result; and

[0014] A first resistor, a second resistor, a first inductor, and a second inductor, wherein the first end of the first resistor is connected to the DC power supply port, the second end of the first resistor is connected to the first end of the first inductor, the second end of the first inductor is connected to the first end of the second inductor, and the second end of the coupling module is connected at the same time, the second end of the second inductor is connected to the first end of the second resistor, and the second end of the second resistor is connected to the ground port. Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the coupling module includes a first capacitor, the first end of the first capacitor is connected to the signal input port, and the second end is connected to the detection module.

[0015] Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the detection module includes a first diode and a third resistor, the anode of the first diode is connected to the second end of the first capacitor, the cathode of the first diode is connected to the first end of the third resistor and is also connected to the voltage comparison module, and the second end of the third resistor is connected to the ground port.

[0016] Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the reference voltage module includes a second diode, a third capacitor, a fourth resistor and a fifth resistor, the anode of the second diode is connected to the first end of the third capacitor and the first end of the fourth resistor, the second end of the fourth resistor is connected to the DC power supply port, the second end of the third capacitor is connected to the ground port, the cathode of the second diode is connected to the first end of the fifth resistor and is also connected to the voltage comparison module, and the second end of the fifth resistor is connected to the ground port.

[0017] Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the reference voltage module further includes an adjustable resistance port, and the adjustable resistance port is connected to the anode of the second diode for adjusting the reference voltage.

[0018] Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the voltage comparison module includes a voltage comparison chip, the power supply end of the voltage comparison chip is connected to the DC power supply port, the first input end of the voltage comparison chip is connected to the detection module, the second input end of the voltage comparison chip is connected to the reference voltage module, the ground end of the voltage comparison chip is connected to the ground port, and the output end of the voltage comparison chip is connected to the output port.

[0019] Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the welding process of each structure adopts eutectic welding.

[0020] Furthermore, in a high-reliability microwave signal detection circuit proposed by the present invention, the eutectic welding principle is that the two solid phases of the component metal base and the contact surface are melted to form a liquid phase, which becomes a eutectic after cooling, and the component is firmly welded to the base.

[0021] Beneficial effects of the present invention:

[0022] The present invention adds two choke inductors at the input voltage divider end to prevent the coupling of the radio frequency signal to the negative input end of the voltage comparison chip when the input power is low, and at the same time weakens the detection voltage that may affect the comparison point voltage when the input power is large. The choke inductor also plays an input impedance matching role, thereby improving the accuracy of the comparison point voltage and the sensitivity of the detection diode. The welding process of each structure of the present invention adopts eutectic welding, which effectively reduces the void rate of components and bases, and finally makes the comparison point reference voltage more stable, thereby improving the dynamic detection range and reliability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the structure of a high-reliability microwave detection circuit;

[0024] Figure 2 This is the schematic diagram of a high-reliability microwave detection circuit. DETAILED DESCRIPTION

[0025] In order to more clearly and completely illustrate the technical solution of the present invention, the present invention is further described below in conjunction with the accompanying drawings.

[0026] See also Figure 1The present invention proposes an embodiment of a highly reliable microwave signal detection circuit, comprising: a signal input port 201, a DC power port 202, a ground port 203, an output port 204, a coupling module 101, a detection module 102, a reference voltage module 103, a voltage comparison module 104, a first resistor R1, a second resistor R2, a first inductor L1 and a second inductor L2. The signal input port 201 is used to access a radio frequency signal, the DC power port 202 is used to access an external DC power supply, and the ground port 203 is used for power supply and signal grounding. The first end of the coupling module 101 is connected to the signal input port for coupling input of a radio frequency signal. The first end of the detection module 102 is connected to the second end of the coupling module for detection and acquisition of a detection voltage signal. The reference voltage module 103 is respectively connected to the DC power port 202 and the ground port 203 for generating a reference voltage. The input end of the voltage comparison module 104 is respectively connected to the second end of the detection module 102 and the output end of the reference voltage module 103 for comparing the detection voltage signal with the reference voltage. The output port 204 is connected to the voltage comparison module and is used to output the voltage comparison result. The first end of the first resistor R1 is connected to the DC power supply port 202, the second end of the first resistor R1 is connected to the first end of the first inductor L1, the second end of the first inductor L1 is connected to the first end of the second inductor L2, and is connected to the second end of the coupling module 101, the second end of the second inductor L2 is connected to the first end of the second resistor R2, and the second end of the second inductor L2 is connected to the ground port 203.

[0027] Specifically, in this embodiment, a high-frequency radio frequency signal is input into the detection circuit through the coupling module 101, and the choke inductor at the input voltage divider terminal plays the role of input impedance matching, and at the same time effectively prevents the coupling of the radio frequency signal to the negative input terminal of the voltage comparison chip when the input power is low, and can also weaken the detection voltage that interferes with the comparison point voltage when the input power is large. The first resistor R1 and the second resistor R2 divide the voltage so that the detection module obtains a DC voltage, and the signal is input to the detection module 102. The detection module uses the unidirectional conductivity of the detection diode to remove the negative half cycle of the input signal, and obtains the detection voltage signal after processing, which is transmitted to the voltage comparison module. The reference voltage module 103 generates a reference voltage and transmits it to the negative input terminal of the voltage comparison module. The voltage comparison module 104 processes the input terminal signal. When the level of the input radio frequency signal is within the specified range, the output level of the voltage comparison module is a TTL low level; when the level of the input radio frequency signal exceeds the specified range, the output TTL level is flipped, thereby making a detection indication. The simulation test results show that when the input signal power is between -20dBm and 5dBm, the voltage fluctuation of the negative terminal comparison point is only 1mV to 4mV within the operating frequency range.

[0028] For further information, see Figure 2In an embodiment of a highly reliable microwave signal detection circuit, a coupling module 101 includes a first capacitor C1, a first end of the first capacitor C1 is connected to a signal input port 201, and a second end is connected to a detection module 102. The coupling module 101 is used to isolate DC interference and couple the RF signal to isolate DC interference.

[0029] For further information, see Figure 2 In an embodiment of a highly reliable microwave signal detection circuit, the detection module 102 includes a first diode D1 and a third resistor R3, the anode of the first diode D1 is connected to the second end of the first capacitor C1, the cathode of the first diode D1 is connected to the first end of the third resistor R3 and the voltage comparison module 105, and the second end of the third resistor R3 is grounded. The detection module 103 receives the microwave signal, the first diode D1 acts as a detection diode, and uses the unidirectional conductivity of the detection diode to remove the negative half cycle of the input signal to obtain a detection signal, which is output to the voltage comparison module 104, and the third resistor R3 provides a path for the DC signal.

[0030] For further information, see Figure 2 In an embodiment of a high-reliability microwave signal detection circuit, a reference voltage module 103 includes a second diode D2, a third capacitor C3, a fourth resistor R4 and a fifth resistor R5, an anode of the second diode D2 is connected to a first end of the third capacitor C3 and a first end of the fourth resistor R4, a second end of the fourth resistor R4 is connected to a DC power supply port 202, a second end of the third capacitor C3 is connected to a ground port 203, a cathode of the second diode D2 is connected to a first end of the fifth resistor R5 and is also connected to a voltage comparison module 105, and a second end of the fifth resistor R5 is grounded; the reference voltage module 103 obtains a DC voltage from the DC power supply port 202.

[0031] For further information, see Figure 2 In an embodiment of a highly reliable microwave signal detection circuit, the reference voltage module further includes an adjustable resistor port RT, and the adjustable resistor port RT is connected to the anode of the second diode D2. The external adjustable resistor is connected to the reference voltage module through the adjustable resistor port RT, and the fourth resistor R4 divides the voltage with the external adjustable resistor to form a reference voltage that is transmitted to the voltage comparison module 104.

[0032] For further information, see Figure 2 In an embodiment of a high-reliability microwave signal detection circuit, the voltage comparison module 104 includes a voltage comparison chip. The present invention does not limit the specific chip, and LM193 can be selected.

[0033] For further information, see Figure 2In an embodiment of a highly reliable microwave signal detection circuit, the power supply terminal of the voltage comparison chip is connected to the DC power supply port 202, the first input terminal of the voltage comparison chip is connected to the detection module 102, the second input terminal of the voltage comparison chip is connected to the reference voltage module 103, and the ground terminal is connected to the ground port 203. The voltage comparison chip is used to process the input signal. When the input signal is lower than the reference voltage, the voltage comparison chip outputs a low level. When the input signal is higher than the reference voltage, the voltage comparison chip outputs a high level.

[0034] Furthermore, in an embodiment of a highly reliable microwave signal detection circuit, the welding process of each structure adopts eutectic welding, and the components are gently rubbed on the metal-plated base to wipe off the unstable oxide layer on the interface, so that the contact surfaces are melted and a liquid phase is formed from two solid phases. The plated metal can be gold. After the liquid phase is cooled, when the temperature is lower than the eutectic point, the grains formed by the liquid phase combine with each other to form a mechanical mixture eutectic crystal, so that the components are firmly welded on the base. Eutectic welding can effectively reduce the void rate of the chip and the base, and ultimately make the comparison point voltage more stable.

[0035] Of course, the present invention may have many other implementations. Based on this implementation, other implementations obtained by ordinary technicians in this field without any creative work are all within the scope of protection of the present invention.

Claims

1. A highly reliable microwave signal detection circuit, characterized in that: include: A signal input port (201) for receiving a radio frequency signal; A DC power port (202) is used to connect to an external DC power supply; A grounding port (203) is used for power supply and signal grounding; A coupling module (101), a first end of which is connected to a signal input port (201) and is used for coupling input of a radio frequency signal; A detection module (102), a first end of which is connected to the second end of the coupling module (101), and is used for detection and obtaining a detection voltage signal; A reference voltage module (103), connected to the DC power port (202) and the ground port (203) respectively, and used to generate a reference voltage; A voltage comparison module (104), whose input end is respectively connected to the second end of the detection module (102) and the output end of the reference voltage module (103), and is used to compare the detection voltage signal with the reference voltage; An output port (204), connected to the voltage comparison module (104), for outputting a voltage comparison result; as well as A first resistor (R1), a second resistor (R2), a first inductor (L1) and a second inductor (L2), wherein the first end of the first resistor (R1) is connected to the DC power supply port (202), the second end of the first resistor (R1) is connected to the first end of the first inductor (L1), the second end of the first inductor (L1) is connected to the first end of the second inductor (L2) and is connected to the second end of the coupling module (101), the second end of the second inductor (L2) is connected to the first end of the second resistor (R2), and the second end of the second resistor (R2) is connected to the ground port (203).

2. A highly reliable microwave signal detection circuit as claimed in claim 1, characterized in that: The coupling module (101) comprises a first capacitor (C1), a first end of the first capacitor (C1) being connected to the signal input port (201), and a second end of the first capacitor (C1) being connected to the detection module (102).

3. A highly reliable microwave signal detection circuit as claimed in claim 2, characterized in that: The detection module (102) comprises a first diode (D1) and a third resistor (R3), wherein the anode of the first diode (D1) is connected to the second end of the first capacitor (C1), the cathode of the first diode (D1) is connected to the first end of the third resistor (R3) and is also connected to the voltage comparison module (104), and the second end of the third resistor (R3) is connected to the ground port (203).

4. A highly reliable microwave signal detection circuit as claimed in claim 3, characterized in that: The reference voltage module (103) comprises a second diode (D2), a third capacitor (C3), a fourth resistor (R4) and a fifth resistor (R5); the anode of the second diode (D2) is connected to the first end of the third capacitor (C3) and the first end of the fourth resistor (R4); the second end of the fourth resistor (R4) is connected to the DC power supply port (202); the second end of the third capacitor (C3) is connected to the ground port (203); the cathode of the second diode (D2) is connected to the first end of the fifth resistor (R5) and is also connected to the voltage comparison module (104); and the second end of the fifth resistor (R5) is connected to the ground port (203).

5. A highly reliable microwave signal detection circuit as claimed in claim 4, characterized in that: The reference voltage module (103) further comprises an adjustable resistance port, wherein the adjustable resistance port is connected to the anode of the second diode (D2) and is used to adjust the reference voltage.

6. A highly reliable microwave signal detection circuit as claimed in claim 1, characterized in that: The voltage comparison module (104) comprises a voltage comparison chip, a power supply end of the voltage comparison chip is connected to the DC power supply port (202), a first input end of the voltage comparison chip is connected to the detection module (102), a second input end of the voltage comparison chip is connected to the reference voltage module (103), a ground end of the voltage comparison chip is connected to the ground port (203), and an output end of the voltage comparison chip is connected to the output port (204).

7. A high-reliability microwave signal detection circuit as claimed in any one of claims 1 to 6, characterized in that: The welding process of each structure adopts eutectic welding.

8. A highly reliable microwave signal detection circuit as claimed in claim 7, characterized in that: The eutectic welding is specifically that two solid phases of the component metal base and the contact surface are melted to form a liquid phase, which becomes a eutectic after cooling, and the component is firmly welded on the base.

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