CN110823142B - Demodulator and demodulation method based on gain phase discriminator coaxial cable strain sensor - Google Patents
Demodulator and demodulation method based on gain phase discriminator coaxial cable strain sensor Download PDFInfo
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- CN110823142B CN110823142B CN201911095537.XA CN201911095537A CN110823142B CN 110823142 B CN110823142 B CN 110823142B CN 201911095537 A CN201911095537 A CN 201911095537A CN 110823142 B CN110823142 B CN 110823142B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B15/00—Measuring arrangements characterised by the use of electromagnetic waves or particle radiation, e.g. by the use of microwaves, X-rays, gamma rays or electrons
- G01B15/06—Measuring arrangements characterised by the use of electromagnetic waves or particle radiation, e.g. by the use of microwaves, X-rays, gamma rays or electrons for measuring the deformation in a solid
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B3/00—Line transmission systems
- H04B3/54—Systems for transmission via power distribution lines
Abstract
The invention discloses a demodulator based on a gain phase discriminator coaxial cable strain sensor, which comprises a digital hardware part and an analog hardware part, wherein the digital hardware part acquires analog data of the analog hardware part and converts the analog data into digital signals for data processing and data transmission, and the analog hardware part comprises a VCO circuit, a power amplifier, a VCO power supply, a filter, a coupler, an RF/IF gain phase discriminator and a microwave switch. Through the mode, the demodulator and the demodulation method based on the gain phase discriminator coaxial cable strain sensor provided by the invention have the advantages that the phase frequency characteristic and the amplitude frequency characteristic of the sensor are detected by the RF/IF gain phase discriminator, the phase information is accurate, the micro deformation of the coaxial cable strain sensor is calculated, the precision is high, the error is small, and the environment adaptability is strong.
Description
Technical Field
The invention relates to the technical field of communication, in particular to a demodulator and a demodulation method based on a gain phase discriminator coaxial cable strain sensor.
Background
The coaxial cable strain sensor is applied to various strain monitoring scenes such as rail deformation monitoring, oil and gas pipeline deformation monitoring, bridge deformation monitoring and the like. The coaxial cable strain sensor is a sensor, and the demodulator demodulates the coaxial cable strain sensor, so that the coaxial cable strain sensor can be applied to a plurality of fields of strain monitoring.
At present, no special regulator and other equipment for demodulating the coaxial cable strain sensor exist in the market, and a vector network analyzer is needed when the coaxial cable strain sensor is demodulated in the prior art. The vector network analyzer is an indispensable measurement scale for product function and performance tests especially in production tests. However, the vector network analyzer is a general electromagnetic wave energy testing device, cannot be applied to practical engineering, has strong limitation on the use environment, is complex in demodulation method, low in measurement accuracy, and is difficult to meet the modern high-accuracy requirement.
Disclosure of Invention
The invention mainly solves the technical problem of providing a demodulator based on a gain phase discriminator and a coaxial cable strain sensor, which adopts an RF/IF gain phase discriminator to detect the phase frequency characteristic and the amplitude frequency characteristic of the sensor, has accurate phase information, calculates the micro deformation of the coaxial cable strain sensor, has high precision, small error and strong environment adaptability, and improves the safety of the coaxial cable.
In order to solve the technical problems, the invention adopts a technical scheme that: the demodulator comprises a digital hardware part and an analog hardware part, wherein the digital hardware part acquires analog data of the analog hardware part and converts the analog data into digital signals for data processing and data transmission;
the digital hardware part comprises an MCU circuit, a power supply, an ADC circuit, a high-frequency board circuit, an interface circuit, a reference voltage circuit, a dial switch, a 485 module and a zigbee module, wherein the MCU circuit is respectively in communication connection with the power supply, the ADC circuit, the high-frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module and the zigbee module;
the analog hardware part comprises a VCO circuit, a power amplifier, a VCO power supply, a filter, a directional coupler, a bidirectional coupler, an RF/IF gain phase discriminator, two paths of microwave switches and six paths of microwave switches, wherein the VCO power supply is connected with the VCO circuit, the VCO circuit is connected with the filter through the power amplifier, the filter is connected with the directional coupler, the directional coupler is respectively connected with a power divider and the bidirectional coupler, the power divider is connected with the RF/IF gain phase discriminator through the two paths of microwave switches, the bidirectional coupler is respectively connected with the six paths of microwave switches and the RF/IF gain phase discriminator, the six paths of microwave switches are connected with a sensor, the RF/IF gain phase discriminator compares two paths of signals to output amplitude gain and phase difference, and one path of signals is shunted through the directional coupler to obtain the output of a coupling end, the other path of signal is a signal reflected by the sensor after passing through the output end of the bidirectional coupler.
In a preferred embodiment of the present invention, the VCO power supply employs an hmc1060 power management chip.
In a preferred embodiment of the present invention, the power divider is a 90 ° power divider.
In order to solve the technical problem, the invention adopts another technical scheme that: the demodulation method of the demodulator based on the gain phase discriminator coaxial cable strain sensor comprises the following specific steps:
a. initialization
The method comprises the following steps of MCU initialization, VCO initialization, external ADC initialization and microwave switch initialization;
b. data snooping
The MCU circuit respectively monitors data of the ADC circuit, the high-frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module and the zigbee module, and respectively receives different task labels through a communication protocol;
c. task execution
And executing the task according to the task label, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, and the task label is cleared after the task is executed and the next task label is waited to be updated.
In order to solve the technical problem, the invention adopts another technical scheme that: the demodulation method of the demodulator based on the gain phase discriminator coaxial cable strain sensor comprises the following specific steps:
a. initialization
The method comprises the following steps of MCU initialization, VCO initialization, external ADC initialization and microwave switch initialization;
b. data snooping
The MCU circuit respectively monitors data of the ADC circuit, the high-frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module and the zigbee module, and respectively receives different task labels through a communication protocol;
c. task execution
And executing the task according to the task label, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, and the task label is cleared after the task is executed and the next task label is waited to be updated.
The invention has the beneficial effects that: the demodulator demodulation method based on the gain phase discriminator coaxial cable strain sensor adopts the RF/IF gain phase discriminator to detect the phase frequency characteristic and the amplitude frequency characteristic of the sensor, has accurate phase information, calculates the micro deformation of the coaxial cable strain sensor, has high precision, small error and strong environment adaptability, and improves the safety of the coaxial cable.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive efforts, wherein:
FIG. 1 is a block diagram of the digital hardware portion of the gain phase discriminator coaxial cable strain sensor based demodulator of the present invention;
FIG. 2 is a schematic diagram of the analog hardware portion of the gain phase discriminator coaxial cable strain sensor based demodulator of the present invention;
fig. 3 is a flow chart of the demodulation method of the demodulator based on the gain phase discriminator coaxial cable strain sensor.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The embodiment of the invention comprises the following steps:
a demodulator based on a gain phase discriminator coaxial cable strain sensor comprises a digital hardware part and an analog hardware part, wherein the digital hardware part acquires analog data of the analog hardware part and converts the analog data into digital signals to perform data processing and data transmission.
As shown in fig. 1, the digital hardware part includes an MCU circuit, a power supply, an ADC circuit, a high frequency board circuit, an interface circuit, a reference voltage circuit, a dial switch, a 485 module, and a zigbee module, where the MCU circuit is in communication connection with the power supply, the ADC circuit, the high frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module, and the zigbee module, respectively.
The main device functions are as follows:
the MCU circuit is a digital hardware core and has the main function of coordinating and controlling the work of each part and carrying out data processing and data transmission;
the ADC circuit mainly has the function of converting an analog signal into a digital signal;
the power supply has the main function of providing a digital hardware power supply and an analog hardware power supply.
As shown in fig. 2, the analog hardware part includes a VCO circuit, a power amplifier, a VCO power supply, a filter, a coupler, an RF/IF gain phase detector, and a microwave switch, the VCO power supply is connected to the VCO circuit, the VCO circuit is connected to the filter through the power amplifier, the filter is connected to the coupler, and the coupler is connected to the RF/IF gain phase detector through the microwave switch.
The main device functions are as follows:
a VCO circuit: generating a radio frequency signal;
RF/IF gain phase detector: detecting the amplitude ratio and the phase difference of the two paths of radio frequency signals;
VCO power supply: four power supplies are generated as required by the VCO circuit.
In this embodiment, the VCO power supply adopts an hmc1060 power management chip, and the coupler includes a directional coupler and a bidirectional coupler connected to each other; the microwave switch comprises two paths of microwave switches and six paths of microwave switches.
Furthermore, the directional coupler is connected with the two paths of microwave switches through the tapping and dividing device. Wherein, the attack divider adopts a 90-degree power divider.
Phase measurement principle:
the RF/IF gain phase detector compares two paths of signals to output amplitude gain and phase difference, wherein one path of signal is output by a coupling end obtained by shunting through the coupler, and the other path of signal is reflected by the sensor after passing through the output end of the coupler. The two signals are compared by an RF/IF gain phase detector to output amplitude gain and phase difference. Meanwhile, the phase shifter is used for comparing twice to obtain twice amplitude gain and phase difference, and phase information can be prepared and determined.
The VCO power supply provides 4 paths of power supplies for the VCO circuit, radio frequency signals generated by the VCO circuit are amplified through a power amplifier, filtered through a filter and shunted through a coupler, and finally the signals are gathered to the RF/IF gain phase discriminator to be processed and output.
As shown in fig. 3, the present invention further provides a demodulation method for a demodulator based on a gain phase discriminator coaxial cable strain sensor, which comprises the following steps:
a. initialization
The method comprises MCU initialization, VCO initialization, external ADC initialization and microwave switch initialization.
The MCU initialization mainly comprises the initialization of pins of a chip, a timer and the interruption thereof, the serial port interruption, the FLASH and the initialization;
the VCO initialization mainly comprises the steps of enabling the VCO and the spi communication function of the VCO, initializing the register function of the VCO and ensuring that correct frequency point signals can be output;
the external ADC initialization is mainly to enable an external ADC chip and initialize the spi communication function of the ADC;
the initialization of the microwave switch is mainly to enable the microwave switch chip and open one of the channels.
b. Data snooping
The MCU circuit monitors data of the ADC circuit, the high-frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module and the zigbee module respectively, and different task labels are received through communication protocols respectively.
When the serial port interruption is triggered, the data cache read-write pointer changes and stops changing within a set time, the cache read-write pointer is compared to fetch data, the data is analyzed according to a specific communication protocol and a command to which the data belongs is judged, and meanwhile, a task tag is updated according to the command.
c. Task execution
And executing the task according to the task label, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, and the task label is cleared after the task is executed and the next task label is waited to be updated.
And after the task tag is updated, executing the task according to the task tag, clearing the task tag after the task is executed, and waiting for the task tag to be updated.
Wherein the content of the first and second substances,
and (3) instruction analysis:
analyzing the instruction content according to the communication protocol, wherein the content comprises sensor parameter configuration, demodulator scanning configuration and demodulator frequency sweeping parameter configuration, and the data transmission instruction is used for analyzing and judging temperature data or strain data;
data transmission:
transmitting required data to an upper computer through a 485 bus or a zigbee wireless network according to the data transmission instruction;
data acquisition:
acquiring data at regular time according to the task label, the sensor configuration parameter, the demodulator frequency sweep parameter and the demodulator scanning parameter;
data processing:
the data processing comprises ADC acquisition filtering, Fourier frequency domain transformation, Fourier time domain transformation, windowing function and peak searching algorithm.
Meanwhile, during data processing, firstly, data are collected through filtering of the ADC circuit, time domain transformation is conducted on the collected data, a time domain map is obtained, windowing is conducted, then frequency domain transformation is conducted to obtain a frequency domain map, a center is searched in the frequency domain map, and data which are the maximum peak point are output as frequency points.
The innovation points of the invention are as follows:
1. detecting the phase frequency characteristic and the amplitude frequency characteristic of the sensor by adopting an RF/IF gain phase discriminator;
2. acquiring a sensor time domain map through fast Fourier transform;
3. windowing, time domain and frequency domain transformation and acquisition of an N frequency doubling point of the sensor are carried out according to the sensor node to be monitored;
4. and calculating the frequency offset according to the N frequency doubling points of the sensor at different moments so as to calculate the micro deformation of the sensor.
In summary, the demodulator and the demodulation method based on the gain phase detector coaxial cable strain sensor of the invention adopt the RF/IF gain phase detector to detect the phase frequency characteristic and the amplitude frequency characteristic of the sensor, have accurate phase information, calculate the micro deformation of the coaxial cable strain sensor, have high precision, small error and strong environment adaptability, and improve the safety of the coaxial cable.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (4)
1. A demodulator based on a gain phase discriminator coaxial cable strain sensor is characterized by comprising a digital hardware part and an analog hardware part, wherein the digital hardware part acquires analog data of the analog hardware part and converts the analog data into digital signals for data processing and data transmission;
the digital hardware part comprises an MCU circuit, a power supply, an ADC circuit, a high-frequency board circuit, an interface circuit, a reference voltage circuit, a dial switch, a 485 module and a zigbee module, wherein the MCU circuit is respectively in communication connection with the power supply, the ADC circuit, the high-frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module and the zigbee module;
the analog hardware part comprises a VCO circuit, a power amplifier, a VCO power supply, a filter, a directional coupler, a bidirectional coupler, an RF/IF gain phase discriminator, two paths of microwave switches and six paths of microwave switches, wherein the VCO power supply is connected with the VCO circuit, the VCO circuit is connected with the filter through the power amplifier, the filter is connected with the directional coupler, the directional coupler is respectively connected with a power divider and the bidirectional coupler, the power divider is connected with the RF/IF gain phase discriminator through the two paths of microwave switches, the bidirectional coupler is respectively connected with the six paths of microwave switches and the RF/IF gain phase discriminator, the six paths of microwave switches are connected with a sensor, the RF/IF gain phase discriminator compares two paths of signals to output amplitude gain and phase difference, and one path of signals is shunted through the directional coupler to obtain the output of a coupling end, the other path of signal is a signal reflected by the sensor after passing through the output end of the bidirectional coupler, the two paths of signals are compared by the RF/IF gain phase discriminator to output amplitude gain and phase difference, and the amplitude gain and the phase difference are obtained twice by the phase shifter through twice comparison, so that phase information can be accurately determined.
2. The gain phase detector coaxial cable strain sensor based demodulator of claim 1, wherein the VCO power supply employs an hmc1060 power management chip.
3. The gain phase detector coaxial cable strain sensor-based demodulator according to claim 1, wherein the power divider is a 90 ° power divider.
4. A demodulation method of a demodulator based on a gain phase detector coaxial cable strain sensor according to any of claims 1 to 3, characterized by comprising the following specific steps:
a. initialization
The method comprises the following steps of MCU initialization, VCO initialization, external ADC initialization and microwave switch initialization;
b. data snooping
The MCU circuit respectively monitors data of the ADC circuit, the high-frequency board circuit, the interface circuit, the reference voltage circuit, the dial switch, the 485 module and the zigbee module, and respectively receives different task labels through a communication protocol;
c. task execution
And executing the task according to the task label, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, and the task label is cleared after the task is executed and the next task label is waited to be updated.
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