Command signal generator for satellite ground test equipment

Abstract

The present invention discloses a command signal generating device for satellite ground test equipment, and the present invention belongs to the field of satellite test technology. The device includes: a narrow pulse signal generating module, a monostable output pulse width adjustable circuit module, and a DC regulated power supply for powering each module; the present invention adds a narrow pulse signal generating module in front of the monostable circuit module, which can generate a pulse signal with a narrower width, and at the same time improves the resistance and capacitance in the monostable circuit to be adjustable; the addition and improvement of the narrow pulse signal generating module and the monostable output pulse width adjustable circuit module make the entire circuit more practical; the circuit can generate a pulse signal with accurately adjustable time and frequency, so the present invention is not only suitable for sending various commands and control information, but also can be applied to the command signal generating device in satellite ground test equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of satellite testing, and in particular relates to a command signal generating device used in satellite ground testing equipment. Background Art

[0002] In the monostable mode, the 555 timer works as a one-shot pulse generator. When the trigger input voltage drops to V CC The output pulse width depends on the time constant of the RC network composed of the timing resistor and capacitor. When the capacitor voltage rises to V CC The output pulse stops when the pulse width reaches 2 / 3 of the original value. The pulse width can be adjusted by changing the time constant of the RC network according to actual needs.

[0003] The working principle of the 555 timer monostable circuit is as follows: 1. When the switch is turned off, there is no trigger signal. After power is turned on, the circuit automatically stops at the steady state of v0=0. The trigger end is pulled up to the power supply through the pull-up resistor. The input is high level, and the internal transistor T D The monostable circuit formed by the 555 timer outputs a low level: Even if there is charge stored in capacitor C1, it will pass through the already turned-on T D Quickly release, so v C ≈0, V C1 =V C2 =0, v0 = 0. I1 (THR terminal) = 0 <V H =2V CC / 3,V I2 (TR I terminal) = V CC >V L =V CC / 3, according to the function table, the output and state of the 555 timer will be maintained at this time, so the stable state is T D When the switch is turned on, the negative pulse makes V I2 Jump to V CC / 3 or less, v0 outputs high level, T D Cut off, the circuit enters a temporary steady state, V CC Start charging the capacitor through the resistor. 3. When the capacitor is charged to v C >V H =2V CC / 3, the output v0 is low level, T D The capacitor discharges rapidly until v C =0, T D The circuit returns to steady state. Therefore, the duration of the transient steady state is the time when the capacitor is charged to V H =2V CC / 3 the time taken, that is, the output pulse width tW , depends on the size of the external resistor R and capacitor C, and is obtained by the three-element method as RC l n3.

[0004] At present, the digital electronic technology basic course experimental system directly uses a 555 timer to form a monostable circuit to generate pulses. Since the trigger signal width is difficult to control, the output pulse width is large and it is difficult to obtain a narrow pulse. Summary of the invention

[0005] In view of this, the present invention provides a command signal generating device for satellite ground test equipment with adjustable output pulse width. The signal generated by pressing a button of the device can be processed by a narrow pulse signal generating module, so that the width of the pulse is greatly reduced, further improving the accuracy in circuit experiments. It not only provides a technical basis for realizing basic experimental tasks of digital electronic technology, but can also be applied to command signal generating devices in satellite ground test equipment.

[0006] The technical solution for implementing the present invention is as follows:

[0007] A command signal generating device for satellite ground test equipment comprises a narrow pulse signal generating module, a monostable output pulse width adjustable circuit module and a DC regulated power supply for supplying power to each module;

[0008] The narrow pulse signal generating module includes an R1 resistor, an R2 resistor, an R3 resistor, a C1 capacitor, a C2 capacitor, a C3 capacitor, a 555 timer T1, an inverter U1 and a switch K1;

[0009] The connection relationship is as follows: the reset terminal RST of the 555 timer T1 is connected to a DC regulated power supply, the trigger terminal TRI is connected to a ground switch K1, and a negative level pulse input signal is generated by turning K1 on and off, and the trigger terminal TRI is connected to a DC regulated power supply via a pull-up resistor R1, and the discharge terminal DIS is connected to the threshold terminal THR; the resistor R2 is connected between the threshold terminal THR of T1 and the power supply terminal VCC, the capacitor C1 is connected between the threshold terminal THR of T1 and the ground GND, and the capacitor C2 is connected between the control terminal CON of T1 and the ground; the output terminal OUT of T1 is connected to the input terminal of the inverter U1, the output terminal of the inverter U1 is connected in series with the capacitor C3 and the resistor R3 to the power supply to form a differential circuit, and the output signal is drawn from between the capacitor C3 and the resistor R3 as the input signal of the monostable output pulse width adjustable circuit module 200;

[0010] The monostable output pulse width adjustable circuit module includes a variable resistor R4, polarized capacitors C4 and C5, and a 555 timer T2;

[0011] The connection relationship is as follows: the reset terminal RST of the 555 timer T2 is connected to the power supply, the trigger terminal TRI of T2 is connected to the output terminal of the narrow pulse signal generating module 100, the discharge terminal DIS is connected to the threshold terminal THR, the variable resistor R4 is connected between the threshold terminal THR of T1 and the power supply terminal VCC, the polarized capacitor C4 is connected between the threshold terminal THR of T2 and the ground GND, the control terminal CON is connected to the ground with the capacitor C5, and the output terminal OUT of T2 outputs the command signal used in the satellite ground test equipment.

[0012] Furthermore, the resistance selection range of the R1 resistor and the R2 resistor described in the present invention is 33-330KΩ, the capacitance selection range of the C1 capacitor and the C2 capacitor is 33p-33μF, and the RC calculated by the C3 capacitor value and the R3 resistor value is less than or equal to 1 / 10 of the input waveform width.

[0013] Furthermore, the resistance value of the R4 variable resistor of the present invention is selected to be 33-330KΩ, and the capacitance value selection interval of the C4 capacitor and the C5 capacitor is 33p-33μF.

[0014] Furthermore, the generating device of the present invention also includes an oscilloscope, which is connected to the output end of the monostable output pulse width adjustable circuit module and is used to display the output signal.

[0015] Compared with the prior art, the present invention has the following advantages and positive effects:

[0016] First, compared with the existing experimental circuits of digital electronic circuits, the present invention is more specifically aimed at monostable circuits, and uses differential circuits to add a narrow pulse signal generating module in front of the monostable circuit module, so that the width of the pulse is greatly reduced, further improving the accuracy in circuit experiments, and having a more complete pulse generating capability; the improvement of the monostable circuit module makes the circuit more practical and can meet the experimental needs under different conditions.

[0017] Second, by adjusting the resistance of the variable resistor R4, the time constant τ can be changed, thereby changing the pulse output signal width. Therefore, the circuit can generate a pulse signal with precisely adjustable time and frequency. Therefore, it can be used to send various commands and control information, and is also used in command signal generating devices in satellite ground test equipment.

[0018] Third, the pulse signal generated by the device of the present invention can be used to simulate the situation where the satellite receives ground commands and conduct ground testing and verification. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 is a circuit schematic diagram of the present invention;

[0021] Figure 2 It is the circuit schematic diagram of the narrow pulse signal generating module;

[0022] Figure 3 It is a circuit schematic diagram of a monostable output pulse width adjustable circuit module;

[0023] In the figure:

[0024] 100—Narrow pulse signal generation module,

[0025] R1 resistor (101), R2 resistor (102), R3 resistor (103), C1 capacitor (101), C2 capacitor (102), C3 capacitor (103), 555 timer T1 (101), inverter U1 (101), switch K1 (101);

[0026] 200—monostable output pulse width adjustable circuit module,

[0027] R4 variable resistor (201), polarized capacitor C4 capacitor (201), C5 capacitor (202), 555 timer T2 (201);

[0028] 300—Oscilloscope,

[0029] 400—DC regulated power supply;

[0030] Figure 4 It is the simulation waveform output by NOT gate U1;

[0031] Figure 5 It is the simulation waveform output by the entire narrow pulse signal generation module;

[0032] Figure 6 It is a rectangular pulse output by the monostable output pulse width adjustable circuit module. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] It should be noted that the following embodiments and features in the embodiments may be combined with each other in the absence of conflict; and, based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making any creative work are within the scope of protection of the present disclosure.

[0035] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on the present disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0036] The following is a detailed description with reference to the accompanying drawings and embodiments:

[0037] like Figure 1 As shown, the embodiment of the present application is a command signal generating device for satellite ground test equipment, including a narrow pulse signal generating module 100, a monostable output pulse width adjustable circuit module 200, an existing oscilloscope 300 and a DC regulated power supply 400;

[0038] The narrow pulse signal generating module and the monostable output pulse width adjustable circuit module are connected in sequence, the output end of the monostable output pulse width adjustable circuit module is connected to the positive input end of the oscilloscope, and the oscilloscope displays the obtained signal waveform through a display.

[0039] The connection relationship is: the output end of the narrow pulse signal generating module 100 is connected to the input end of the monostable output pulse width adjustable circuit module 200, and the output end of the monostable output pulse width adjustable circuit module 200 is connected to the positive input end of the oscilloscope module 300; the DC regulated power supply 400 supplies power to the narrow pulse signal generating module 100 and the monostable output pulse width adjustable circuit module 200.

[0040] like Figure 1-2 As shown, the narrow pulse signal generating module 100 is a circuit composed of a differential circuit and a 555 timer, including an R1 resistor (101), an R2 resistor (102), an R3 resistor (103), a C1 capacitor (101), a C2 capacitor (102), a C3 capacitor (103), a 555 timer T1 (101), an inverter U1 (101), and a switch K1 (101);

[0041] The connection relationship is: the power supply terminal VCC of 555 timer T1 is powered by 5V of DC regulated power supply 400, the GND terminal is grounded, the reset terminal RST is connected to the power supply, and its trigger terminal TRI is used as the trigger signal input terminal. The ground switch K1 is connected to the trigger terminal TRI of T1, and a negative level pulse input signal is generated by K1 on and off, and the trigger terminal TR I is connected to the power supply through the pull-up resistor R1; and by connecting the discharge terminal DIS to the threshold terminal THR, the 555 timer T1 inverter output voltage v OD Connect to v I1 The resistor R2 is connected between the threshold terminal THR of T1 and the power supply terminal VCC, the capacitor C1 is connected between the threshold terminal THR of T1 and the ground GND, the control terminal CON is connected to the capacitor C2, the output terminal OUT of T1 is connected to the input terminal of the inverter U1, the output terminal of the inverter U1 is connected in series with the capacitor C3 and the resistor R3 to the power supply to form a differential circuit, and the output signal is drawn from between the capacitor C3 and the resistor R3 as the input signal of the monostable output pulse width adjustable circuit module 200.

[0042] The resistance value selection range of resistor R1 (101) and resistor R2 (102) is 33-330KΩ, the capacitance value selection range of capacitor C1 (101) and capacitor C2 (102) is 33p-33μF, and the capacitance value of C3 and the resistance value of R3 are generally less than or equal to 1 / 10 of the input waveform width. The 555 timer chip uses NE555P.

[0043] Its working mechanism is: Pressing switch K1 causes the trigger terminal TRI of T1 to be grounded, and a low-level pulse input to T1 causes the voltage V I2 Jump to V CC / 3 or less, v0 outputs high level, T D Cut off, the circuit enters a temporary steady state, V CC The capacitor C1 starts to be charged through the resistor R2; when the capacitor C1 is charged to v C =V H =2V CC / 3, the output v0 is low level, T D The capacitor discharges rapidly until v C =0, T D The high-level rectangular pulse output by T1 is inverted by the inverter U1, and then passes through the differential circuit composed of capacitor C3 and resistor R3 to the power supply to become a negative spike pulse wave, which is used as the output signal of the narrow pulse signal generating module 100 and output to the monostable output pulse width adjustable circuit module 200 of the next stage.

[0044] The width of the spike pulse waveform output by the differential circuit composed of capacitor C3 and resistor R3 is related to capacitor C3 and resistor R3 (i.e., the time constant τ of the circuit). The smaller R3C3 is, the sharper the spike pulse waveform is, and vice versa. The RC of this circuit must be less than the width of the input waveform, otherwise it loses the function of waveform conversion and becomes a general RC coupling circuit. Generally, RC is less than or equal to 1 / 10 of the width of the input waveform.

[0045] like Figure 1 , 3 As shown, the monostable output pulse width adjustable circuit module 200 is a monostable circuit composed of a variable resistor circuit and a 555 timer, including an R4 variable resistor (201), a polar capacitor C4 capacitor (201), a C5 capacitor (202), and a 555 timer T2 (201);

[0046] The connection relationship is: the power supply terminal VCC of the 555 timer T2 is powered by the 5V of the DC regulated power supply 400, the GND terminal is grounded, the reset terminal RST is connected to the power supply, and the trigger terminal TRI of T2 is the output terminal of the narrow pulse signal generating module 100 of the previous level; and by connecting the discharge terminal DIS to the threshold terminal THR, the output voltage v of the inverter of the 555 timer T2 is OD Connect to v I1 The variable resistor R4 is connected between the threshold terminal THR of T1 and the power supply terminal VCC, the polar capacitor C4 is connected between the threshold terminal THR of T1 and the ground GND, the control terminal CON is connected to the ground through the capacitor C5, and the output terminal OUT of T2 is connected to the input terminal of the oscilloscope 300.

[0047] The resistance value of the variable resistor R4 (201) is selected to be 33-330KΩ, and the capacitance value range of the capacitor C4 (201) and the capacitor C5 (202) is selected to be 33p-33μF; the 555 timer chip is selected to be NE555P.

[0048] Its working mechanism is: after the negative spike pulse wave low level pulse output by the upper level narrow pulse signal generating module 100 is input, the voltage V I2 Jump to V CC / 3 or less, v0 outputs high level, T D Cut off, the circuit enters a temporary steady state, V CC The capacitor C4 starts to be charged through the resistor R4; when the capacitor C4 is charged to v C =V H =2V CC / 3, the output v0 is low level, T D The capacitor discharges rapidly until v C =0, T DThe circuit is turned off and returns to a steady state. The width of the rectangular pulse signal output by the monostable output pulse width adjustable circuit module 200 is related to the variable resistor R4 and the capacitor C4. The smaller the R4C4, the narrower the pulse signal, and vice versa. By adjusting the resistance value of the variable resistor R4, the time constant τ can be changed, thereby changing the pulse output signal width, and realizing the command signal generation function with adjustable pulse signal width.

[0049] The oscilloscope 300 can display the pulse wave processed by the circuit on the display screen, which is convenient for studying the properties of the waveform.

[0050] Working mechanism

[0051] The main function of the present invention is to generate a wide pulse signal by lightly touching the switch. After being processed by the narrow pulse signal generating module 100, the original wide pulse signal is converted into a narrow peak pulse signal with a width as low as 1ms, and the narrow pulse signal is input into the monostable output pulse width adjustable circuit module 200 to output a rectangular wave. The waveform is printed in the oscilloscope 300, and the shape and properties of the waveform can be observed to complete the teaching experiment task.

[0052] The present invention adds a narrow pulse signal generating module in front of the monostable circuit module, which can generate a pulse signal with a narrower width, and at the same time improves the resistance and capacitance in the monostable circuit to be adjustable; the addition and improvement of the narrow pulse signal generating module and the monostable output pulse width adjustable circuit module make the entire circuit more practical; the circuit can generate a pulse signal with accurately adjustable time and frequency, so the present invention is not only suitable for sending various commands and control information, but also can be applied to a command signal generating device in satellite ground test equipment; it can also be used to simulate the situation where the satellite receives a ground command to perform ground testing and verification.

[0053] Experimental Results

[0054] After multiple experiments, the improved experimental circuit can generate a signal with a pulse width of 1ms-1s, which meets the requirements of the experimental task. The experimental circuit has a simple structure and is easy to connect the circuit and components. The circuit is simulated by Multisim software to draw the voltage change waveform.

[0055] In the narrow pulse signal generating module 100, the OUT pin level of the 555 timer T101 is output through the NOT gate U101. The simulation waveform is as follows: Figure 4 shown.

[0056] Select parameter R in simulation circuit 102 =30kΩ,C 101 =10uF, the negative pulse width in the simulation waveform is 329.48ms. After theoretical analysis and calculation, it is found that the simulation results are basically consistent with the theoretical calculation values.

[0057] In the narrow pulse signal generating module 100, the output of the NOT gate U101 passes through the differential circuit to generate a negative peak pulse for the next level module. The output V o The simulation waveform is as follows Figure 5 shown.

[0058] Theoretical analysis shows that after a time constant R 103 C 103 After s, the steady-state response component 5V will be basically restored. In the simulation circuit, select parameter R 103 =1kΩ,C 103 =1uF, the negative peak pulse width in the simulation waveform is 1.01ms. The simulation results are basically consistent with the theoretical calculation values.

[0059] The monostable output pulse width adjustable circuit module 200 receives the trigger of the upper level module 100 and outputs an adjustable rectangular pulse. Its simulation waveform is as follows: Figure 6 shown.

[0060] Select parameter R in simulation circuit 201 =2kΩ,C 201 =500uF, the negative pulse width in the simulation waveform is 1093.24ms. After theoretical analysis and calculation, it is found that the simulation results are basically consistent with the theoretical calculation values.

[0061] application

[0062] Since the circuit of the present invention can generate a pulse signal with a duration and frequency that can be precisely adjusted, the present invention is not only suitable for sending various commands and control information, but can also be applied to the command signal generating device in satellite ground test equipment; it can also be used to simulate the situation where the satellite receives ground commands to perform ground testing and verification.

[0063] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A command signal generating device for satellite ground test equipment, characterized in that: It includes a narrow pulse signal generating module, a monostable output pulse width adjustable circuit module and a DC regulated power supply; The connection relationship is: the output end of the narrow pulse signal generating module is connected to the input end of the monostable output pulse width adjustable circuit module, and the DC regulated power supply is connected to the narrow pulse signal generating module and the monostable output pulse width adjustable circuit module to supply power to each module; wherein, The narrow pulse signal generating module includes an R1 resistor, an R2 resistor, an R3 resistor, a C1 capacitor, a C2 capacitor, a C3 capacitor, a 555 timer T1, an inverter U1 and a switch K1; The connection relationship is as follows: the reset terminal RST of the 555 timer T1 is connected to a DC regulated power supply, the trigger terminal TRI is connected to a ground switch K1, and a negative level pulse input signal is generated by turning K1 on and off, and the trigger terminal TRI is connected to a DC regulated power supply via a pull-up resistor R1, and the discharge terminal DIS is connected to the threshold terminal THR; the resistor R2 is connected between the threshold terminal THR of T1 and the power supply terminal VCC, the capacitor C1 is connected between the threshold terminal THR of T1 and the ground GND, and the capacitor C2 is connected between the control terminal CON of T1 and the ground; the output terminal OUT of T1 is connected to the input terminal of the inverter U1, the output terminal of the inverter U1 is connected in series with the capacitor C3 and the resistor R3 to the power supply to form a differential circuit, and the output signal is drawn from between the capacitor C3 and the resistor R3 as the input signal of the monostable output pulse width adjustable circuit module.

2. The command signal generating device for satellite ground test equipment according to claim 1, characterized in that: The monostable output pulse width adjustable circuit module includes a variable resistor R4, polarized capacitors C4 and C5, and a 555 timer T2; The connection relationship is as follows: the reset terminal RST of the 555 timer T2 is connected to the power supply, the trigger terminal TRI of T2 is connected to the output terminal of the narrow pulse signal generating module 100, the discharge terminal DIS is connected to the threshold terminal THR, the variable resistor R4 is connected between the threshold terminal THR of T1 and the power supply terminal VCC, the polarized capacitor C4 is connected between the threshold terminal THR of T2 and the ground GND, the control terminal CON is connected to the ground with the capacitor C5, and the output terminal OUT of T2 outputs the command signal used in the satellite ground test equipment.

3. The command signal generating device for satellite ground test equipment according to claim 2, characterized in that: The resistance selection range of the R1 resistor and the R2 resistor is 33-330KΩ, the capacitance selection range of the C1 capacitor and the C2 capacitor is 33p-33μF, and the RC calculated by the C3 capacitor value and the R3 resistor value is less than or equal to 1 / 10 of the input waveform width.

4. The command signal generating device for satellite ground test equipment according to claim 3, characterized in that: The resistance value of the R4 variable resistor is selected to be 33-330KΩ, and the capacitance value selection range of the C4 capacitor and the C5 capacitor is 33p-33μF.

5. The command signal generating device for satellite ground test equipment according to claim 1, characterized in that: The generating device also includes an oscilloscope, which is connected to the output end of the monostable output pulse width adjustable circuit module and is used to display the output signal.

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