Invention content
A kind of detection signal generating circuit of present invention offer and self-checking system, the amplitude stability of the detection signal of generation, phase
Position is consistent, and frequency is accurate.
In a first aspect, the present invention provides a kind of detection signal generating circuit, including:Power module, at least two voltages letter
Number generation module, handover module, controller, clock generation module and frequency generation module;
At least one of described at least two voltage signals generation module of the power module connection, described at least two
Voltage signal generation module is all connected with the handover module, the clock generation module, the frequency generation module, described
Handover module is separately connected the controller;
The power supply, for providing power supply at least one of described at least two voltage signals generation module;
At least two voltage signals generation module, for generating at least two electricity different, with default amplitude
Press signal, and the voltage signal output of different by described at least two, default amplitude;
The clock generation module, the clock signal for generating predeterminated frequency, and the clock signal is sent
To the controller;
The frequency generation module, the frequency signal for generating predeterminated frequency, and the frequency signal is sent to institute
State controller;
The controller, for according to the rising edge or failing edge of the clock signal be the start trigger time, generate with
The switch-over control signal of the corresponding frequency of the frequency signal, and the switch-over control signal is sent to the handover module;
The handover module is used for according to the switch-over control signal, in at least two voltage signals generation module
Between switch, and corresponding voltage signal is exported.
Preferably, the circuit further includes:Attenuation module;
The controller is additionally operable to, and the switch-over control signal is sent to the attenuation module;
The attenuation module connects the handover module and the controller, for being controlled according to the switch-over control signal
The voltage signal that the attenuation module exports the handover module exports after decaying.
Preferably, the circuit further includes:Amplifier module;
The amplifier module connects the attenuation module, the voltage signal after decaying for being exported to the attenuation module
It carries out amplifier and exports.
Preferably, at least two voltage signals generation module includes:High level signal generation module and low level letter
Number generation module.
Preferably, the high level signal generation module includes:Power module and reference voltage chip;
The power module connects the reference voltage chip;
The power module, for providing power supply for the reference voltage chip;
The reference voltage chip, the voltage signal for the power supply to be converted into the default amplitude.
Preferably, the clock generation module and the frequency generation module become one, using GPS module.
Preferably, the handover module is single-pole double-throw switch (SPDT), and the attenuation module is ADG1604 analog switches, described
Amplifier module is ADA4898-1 operational amplifiers.
Second aspect, the present invention also provides a kind of self-checking systems, including the detection signal generating circuit, controllable electric power
Switch, main circuit, processing module, controllable selecting switch and self-checking command input module;
The main circuit includes main circuit signal source and main circuit measuring circuit, and the controllable selecting switch includes control terminal
With two signal ends, the controllable power switch includes control terminal and two power ends;
The control terminal of the self-checking command input module, the processing module and the controllable selecting switch is sequentially connected,
Two power ends of the controllable selecting switch are separately connected the output end of the detection signal generating circuit and the main circuit
Measuring circuit, two power ends of the controllable selecting switch are also respectively connected with the main circuit signal source of the main circuit and described
Main circuit measuring circuit, the processing module are also connected with the controller, and the controller connects the controllable power switch
Two power ends of control terminal, the controllable power switch are separately connected the power module and at least two voltage signal
At least one of generation module;
The self-checking command input module is sent to the processing for generating self-checking command, and by the self-checking command
Module;
The processing module is used for according to the self-checking command, to the controllable selecting switch transmission switching command, and to
The controller sending action instruction, so that the controller is closed according to the action command to controllable power switch transmission
Close instruction;
The controllable selecting switch, for according to the switching command, the main circuit signal source to be switched to the inspection
Survey signal generating circuit;
The controllable power switch, two power ends for realizing the controllable power switch according to the close command
Connection conducting.
As shown from the above technical solution, the present invention uses the voltage signal generation module with default amplitude, using default
The frequency signal of frequency and the clock signal of predeterminated frequency control handover module in at least two voltage signals generation module
Between switch, therefore can guarantee generate every time detection signal amplitude stability, phase is consistent, and frequency is accurate.
Specific implementation mode
With reference to the accompanying drawings and examples, the specific implementation mode of the present invention is described in further detail.Implement below
Example is not limited to the scope of the present invention for illustrating the present invention.
Fig. 1 is the functional block diagram for the detection signal generating circuit that one embodiment of the invention provides.
As shown in Figure 1, a kind of detection signal generating circuit of the present embodiment, including:Power module 11, at least two voltages
Signal generation module 12 (including first voltage signal generation module to N voltage signals generation module shown in Fig. 1-4), switching
Module 13, controller 14, clock generation module 15 and frequency generation module 16;The power module 11 connect it is described at least
At least one of two voltage signal generation modules 12, at least two voltage signals generation module 12 are all connected with described cut
Block 13 is changed the mold, the clock generation module 15, the frequency generation module 16, the handover module 13 are separately connected described
Controller 14;The power supply, for providing power supply at least one of described at least two voltage signals generation module 12;Institute
At least two voltage signal generation modules 12 are stated, for generating at least two voltage signals different, with default amplitude, and
By the voltage signal output of described at least two different, default amplitudes;The clock generation module 15, it is pre- for generating
If the clock signal of frequency, and the clock signal is sent to the controller 14;The frequency generation module 16, for giving birth to
It is sent to the controller 14 at the frequency signal of predeterminated frequency, and by the frequency signal;The controller 14 is used for basis
The rising edge or failing edge of the clock signal are the start trigger time, are generated with the switching of the corresponding frequency of the frequency signal
Signal is controlled, and the switch-over control signal is sent to the handover module 13;The handover module 13, for according to
Switch-over control signal switches between at least two voltage signals generation module 12, and corresponding voltage signal is exported.
The present invention uses the voltage signal generation module 12 with default amplitude, using the frequency signal of predeterminated frequency and pre-
If the clock signal control handover module 13 of frequency switches between at least two voltage signals generation module 12, therefore can
Ensure the amplitude stability of detection signal generated every time, phase is consistent, and frequency is accurate.
It is worth noting that when generating self-test signal using present invention detection signal generating circuit, self-test signal voltage
For peak ranges from several volts to millivolt level or even microvolt grade, accuracy is higher, and frequency measurement is generally in tens Hz to kHz up to a hundred, frequency
Rate span is big, and to obtain the transfer function response of more wide frequency ranges, harmonic measure realization may be used.
Fig. 2 is the functional block diagram for the detection signal generating circuit that another embodiment of the present invention provides.
With reference to Fig. 2, as a kind of preferred embodiment, the circuit further includes:Attenuation module 17;
The controller 14 is additionally operable to, and the switch-over control signal is sent to the attenuation module 17;
The attenuation module 17 connects the handover module 13 and the controller 14, for being believed according to the switching control
The voltage signal that number control attenuation module 17 exports the handover module 13 exports after decaying.
As a kind of preferred embodiment, the circuit further includes:Amplifier module 18;
The amplifier module 18 connects the attenuation module 17, the electricity after decaying for being exported to the attenuation module 17
Pressure signal carries out amplifier and exports.
The present invention detect signal generating circuit can be used for generating self-test signal, when generating square wave self-test signal, it is described extremely
Two voltage signal generation modules 12 include less:High level signal generation module and low level signal generation module.
As a kind of preferred embodiment, the high level signal generation module includes:Power module 11 and reference voltage core
Piece;
The power module 11 connects the reference voltage chip;
The power module 11, for providing power supply for the reference voltage chip;
The reference voltage chip, the voltage signal for the power supply to be converted into the default amplitude.In addition to reference
Voltage chips also can be used any electronic device that other skilled in the art is contemplated that and realize the function, herein no longer
It repeats.
In order to keep detection signal frequency precisely consistent with the detection signal phase generated every time, as a kind of preferred implementation
Example, the clock generation module 15 and the frequency generation module 16 become one, using GPS module.
The GPS can generate PPS signal and obtain 10MHz stable clock signals according to GPS output waveforms.Believed using PPS
Number rising edge triggering frequency dividing is carried out to the clock signal of 10MHz, can make the detection signal phase that generates every time it is consistent,
Frequency is accurate.
In the present embodiment, the clock signal guarantee that the frequencies omega of signal is provided by GPS is detected, and by clock signal and control
Device 14 processed ensures the phase equalization of detection signal.The handover module 13 is single-pole double-throw switch (SPDT), and the attenuation module 17 is
ADG1604 analog switches 43, the amplifier module 18 are ADA4898-1 operational amplifiers.
In practical operation, the modules noise such as high-accuracy Voltage Reference, precision resistance decaying all within the allowable range can be with
Ignore, the main noise for considering switching noise and low-noise operational amplifier 44, therefore it is noted that the voltage noise of amplifier when selection amplifier
Parameter is small as possible, and single-pole double-throw switch (SPDT) and selecting switch will select the chip that parasitic capacitance is small, conducting resistance consistency is good,
When PCB design it is noted that using the design for reducing parasitic capacitance and inductance, decay for reducing high-frequency harmonic.
Fig. 3 is the functional block diagram for the self-checking system that one embodiment of the invention provides.
As shown in figure 3, a kind of self-checking system, including the detection signal generating circuit, controllable power switch 21, main electricity
Road, processing module 26, controllable selecting switch 24 and self-checking command input module 25;
The main circuit includes main circuit signal source 22 and main circuit measuring circuit 23, and the controllable selecting switch 24 includes
Control terminal and two power ends, the controllable power switch 21 include control terminal and two power ends;
The control terminal of the self-checking command input module 25, the processing module 26 and the controllable selecting switch 24 is successively
Connection, two power ends of the controllable selecting switch 24 are separately connected the output end of the detection signal generating circuit and described
Two power ends of main circuit measuring circuit 23, the controllable selecting switch 24 are also respectively connected with the main circuit letter of the main circuit
Number source 22 and the main circuit measuring circuit 23, the processing module 26 are also connected with the controller 14, and the controller 14 connects
The control terminal of the controllable power switch 21 is connect, two power ends of the controllable power switch 21 are separately connected the power supply mould
At least one of block 11 and at least two voltage signals generation module 12;
The self-checking command input module 25 is sent to the place for generating self-checking command, and by the self-checking command
Manage module 26;
It is understood that the self-checking command input module 25 can be the startup of the first main circuit and the second main circuit
Button, or an individual button.
The processing module 26, for according to the self-checking command, switching command to be sent to the controllable selecting switch 24,
And instructed to 14 sending action of the controller, so that the controller 14 is opened according to the action command to the controllable electric power
It closes 21 and sends close command;
It is understood that sending switching command to the controllable selecting switch 24 and to 14 sending action of the controller
The sequence of instruction is generally first sends switching command to the controllable selecting switch 24, then refers to 14 sending action of the controller
It enables, is complete to ensure to detect the self-test signal that signal generating circuit generates at this time.
The controllable power switch 21, two electricity for realizing the controllable power switch 21 according to the close command
The connection of source is connected.
Self-checking command input module 25 of the present invention generates self-checking command, and the self-checking command is sent to the place
Module 26 is managed, according to the self-checking command, sends switching command to the controllable selecting switch 24, and send out to the controller 14
Action command, the controller 14 is sent to send close command to the controllable power switch 21 according to the action command, at this time
Main circuit obtains electric, generation self-test signal using the detection signal generating circuit, according to self-test signal progress self-test.This hair
It is bright that self-test signal, the amplitude of self-test signal are generated as self-test signal generative circuit due to the use detection signal generating circuit
Stablize, phase is consistent, and frequency is accurate, therefore can guarantee the stability of each self-test signal of main circuit, to ensure self-detection result
It is accurate.
As shown in figure 4, a kind of self-checking system of portable near surface frequency domain electromagnetic methods observation system, including detection signal
Generative circuit (detect signal generating circuit at this time and be equivalent to self-test signal generative circuit, for generating self-test signal), the first sky
Wire-core coil sensor 311, the first controllable selecting switch 312, the first RFI313, the first ADC314, the second controllable selecting switch
322, the 2nd RFI323, the 2nd ADC324 and central processing platform (being equivalent to the processing module 26);(it is not shown in figure self-test
Instruction input module);
The first air core coil sensor 311, the first RFI313, the first ADC314 and the central processing platform are successively
Connection, the central processing platform are also respectively connected with the control of the first controllable selecting switch 312 of the detection signal generating circuit
The control terminal at end processed and the controllable power switch 21;
Wherein, the first air core coil sensor 311, the first RFI313, the first ADC314 are equivalent to the first main circuit,
The first air core coil sensor 311 is equivalent to the signal source of the first main circuit, and the first RFI313, the first ADC314 are equivalent to
The main circuit measuring circuit 23 of first main circuit;
The second air core coil sensor 321, the 2nd RFI323, the 2nd ADC324 and the central processing platform are successively
Connection, the central processing platform are also respectively connected with the control of the second controllable selecting switch 322 of the detection signal generating circuit
End processed;
Wherein, the second air core coil sensor 321, the 2nd RFI323, the 2nd ADC324 are equivalent to the second main circuit,
The second air core coil sensor 321 is equivalent to the signal source of the second main circuit, and the 2nd RFI323, the 2nd ADC324 are equivalent to
The main circuit measuring circuit 23 of second main circuit.
The operation principle of self-checking system of the portable near surface frequency domain electromagnetic methods observation system of the present invention is:
When normal condition, the first main circuit and the connection of the second main circuit are connected the first controllable selecting switch 312, i.e., described
First air core coil sensor 311 and the second air core coil sensor 321 are as the first main circuit and the second main circuit
Signal source;When needing self-test, self-checking command input module 25 generates self-checking command, and will and the self-checking command be sent to institute
Central processing platform is stated, central processing platform is according to the self-checking command, to the described first controllable selecting switch 312 and/or
Two controllable selecting switch 322 send switching command, and are instructed to 14 sending action of the controller, and the controller 14 is according to institute
It states action command and sends close command to the controllable power switch 21, the first controllable selecting switch 312 and/or second can
Selecting switch 322 is controlled according to the switching command, the first air core coil sensor 311 and/or the second air core coil are passed
Sensor 321 is switched to the detection signal generating circuit (using self-test signal as signal source), the controllable power switch
21 are closed according to the close command, generate self-test signal, proceed by self-test.
Self-checking system as shown in Figure 5 includes mainly:The reference voltage chip 41 of model ADR5040, model
The first single-pole double-throw switch (SPDT) 42 of ADG819, central processing platform FPGA, the analog switch 43 of model ADG1604, model
The low-noise operational amplifier 44 of ADA4898-1 and the second single-pole double-throw switch (SPDT) 45 of model 24ADG819;GPS is not shown.
5V power supplys connect the power input of benchmark voltage chips 41, and the output of reference voltage chip 41 connects the first hilted broadsword
The first input end S1 of commutator 42, the second input terminal S2 ground connection of reference voltage chip 41, reference voltage chip 41 it is defeated
Outlet is opened by the input terminal of an input terminal and low-noise operational amplifier 44 of a divider resistance R2 connections analog switch 43, simulation
The third end of pass 43 is grounded by divider resistance R1, and another input terminal of low-noise operational amplifier 44 is grounded by feedback resistance R3,
The input terminal (one end of ground connection) of low-noise operational amplifier 44 is connected with the parallel connection electricity of feedback resistance R4 and capacitance C between output end
Road, an input terminal of output the second single-pole double-throw switch (SPDT) 45 of connection of low-noise operational amplifier 44, the second single-pole double-throw switch (SPDT) 45
Output end connects system to be measured.
The square wave that the duty ratio that the central processing platform FPGA of self-checking system of the present invention can input 1-100,000HZ is 50%
Signal (can pass through above-mentioned GPS) so that single-pole double-throw switch (SPDT) ADG819 output signal frequencies are also 1-100, the duty ratio of 000HZ
For 50% square-wave signal, and it is 2.048V (voltage magnitude of reference voltage chip 41ADR5040 outputs) to export peak value, is passed through
The attenuation array of analog switch 43ADG1604 compositions selects suitable attenuation coefficient, and signal is sent into low noise fortune after overdamping
In the amplification buffer for putting 44ADA4898-1 compositions, low noise is determined here by the multiple of feedback resistance R3 and feedback resistance R4
The amplification factor of sound amplifier 44ADA4898-1, the R3 being arranged in emulation experiment is hanging, R4=10 Ω, and composition one follows directly after
Circuit.Capacitance C is used for doing with outer filtering, filters out unwanted high-frequency signal, and last signal inputs controllable selecting switch
In 24ADG819, for selecting normally measurement or self-test.
It is worth noting that in the present embodiment, low level signal is earth signal, to simplify low-level circuit structure,
And then simplify the structure of entire detection signal generating circuit.
In order to ensure the consistency of phase, using time service principle, first the GPS 10MHz signals generated are ready to, when next
It is divided using the rising edge of the signal triggering 10MHz clock signals when a PPS signal arrives, while opening all switches
Signal, starts data acquisition, and the collected phase error of signal each in this way will be the error and a 10MHz clock of PPS
The sum of signal jitter error, therefore ensure that the consistency of self-test signal phase, also ensure the stability of self-test signal frequency.
The transmission function formula that self-test signal generates is as follows:
C, R in formula1、R2、R3And R4Meaning with above-mentioned Fig. 5, repeat no more, C is filter capacitor, R1、R2Respectively divide
Resistance, R3And R4For the feedback resistance of amplifier.
In formula (3-23) resistance parameter will not carry circuit phase and frequency characteristic, remove the steady component of the system,
It can be reduced to:
X after simplification is R4C, the present invention in value range about in 10-6~10-3, the frequency that can be exported as needed
Rate adjusts the parameter, generally takes 10-5.Carry out Bode and Nyquist analyses.
One of ordinary skill in the art will appreciate that:The above embodiments are only used to illustrate the technical solution of the present invention., and
It is non-that it is limited;Although present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art
It should be understood that:Its still can with technical scheme described in the above embodiments is modified, either to which part or
All technical features carries out equivalent replacement;And these modifications or replacements, it does not separate the essence of the corresponding technical solution this hair
Bright claim limited range.