阅读说明：本技术 基于混频器与功率检波器应变传感器的解调仪及解调方法 (Demodulator and demodulation method based on frequency mixer and power detector strain sensor ) 是由 王念勇 魏明辉 白铁瑛 于 2019-11-11 设计创作，主要内容包括：本发明公开了一种基于混频器与功率检波器应变传感器的解调仪,包括数字硬件部分和模拟硬件部分,所述的数字硬件部分控制模拟硬件部分采集的模拟数据,并且将模拟数据转化为数字数据,进行数据处理以及数据传输。通过上述方式,本发明提供的基于混频器与功率检波器应变传感器的解调仪及解调方法,用于电缆管道形变监测,采用混频器检测传感器的相频特性,采用功率检波器检测传感器的幅频特性,计算同轴电缆应变传感器发生的微小形变,精度高、误差小、环境适应能力强。(The invention discloses a demodulator based on a mixer and a power detector strain sensor, which comprises a digital hardware part and an analog hardware part, wherein the digital hardware part controls analog data acquired by the analog hardware part, converts the analog data into digital data, and performs data processing and data transmission. Through the mode, the demodulator and the demodulation method based on the mixer and the power detector strain sensor are used for cable pipeline deformation monitoring, the mixer is used for detecting the phase-frequency characteristic of the sensor, the power detector is used for detecting the amplitude-frequency characteristic of the sensor, the micro deformation of the coaxial cable strain sensor is calculated, and the demodulator and the demodulation method are high in precision, small in error and strong in environment adaptability.)

1. A demodulator based on a mixer and a strain sensor of a power detector is characterized by comprising a digital hardware part and an analog hardware part, wherein the digital hardware part controls analog data collected by the analog hardware part, converts the analog data into digital data, and performs data processing and data transmission,

the digital hardware part comprises an MCU circuit, a power supply, an ADC circuit, a high-frequency plate circuit, an interface circuit, an inverse voltage circuit, a dial switch, a 485 module and an adder follower circuit, wherein the MCU circuit is respectively in communication connection with the power supply, the ADC circuit, the high-frequency plate circuit, the interface circuit, the inverse voltage circuit, the dial switch, the 485 module and the adder follower circuit;

the analog hardware part comprises a VCO circuit, a power amplifier, a VCO power supply, a filter, a coupler, a mixer, a tapping divider, a phase shifter and a power detector, 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 coupler, the coupler is respectively connected with the mixer, the tapping divider and a microwave switch, the phase shifter is connected between the mixer and the power divider, and the power detector is connected with the microwave switch.

2. The mixer and power detector strain sensor based demodulator of claim 1, wherein the VCO power supply generates four power supplies required by the VCO circuitry.

3. The mixer and power pickup strain sensor based demodulator of claim 1, wherein the coupler comprises a directional coupler and a bi-directional coupler, the directional coupler is connected to the mixer, and the bi-directional coupler is connected to the tap splitter and the microwave switch, respectively.

4. The mixer and power-detector strain sensor-based demodulator of claim 1, wherein the microwave switch is a six-way microwave switch.

5. A demodulation method of a demodulator based on a mixer and a power detector strain sensor is characterized by comprising the following specific steps:

a. initialization

The method comprises the 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 reverse-phase voltage circuit, the dial switch, the 485 module and the adder follower circuit, different task labels are respectively received through a communication protocol, and then an analysis instruction is distributed to the task labels;

c. task execution

And executing the task according to the task tag, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, clearing the task tag after executing the task once, and waiting for updating the next task tag.

Technical Field

The invention relates to the technical field of communication, in particular to a demodulator and a demodulation method based on a mixer and a power detector strain sensor.

Background

The coaxial cable strain sensor is a sensor, and can be applied to the scenes of strain monitoring, such as pipeline deformation monitoring, bridge deformation monitoring, rail deformation monitoring and the like. The demodulator demodulates the coaxial cable strain sensor, so that the demodulator 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 mixer and a power detector strain sensor, which is used for cable pipeline deformation monitoring, adopts the mixer to detect the phase frequency characteristic of the sensor and adopts the power detector to detect the amplitude frequency characteristic of the sensor, calculates the micro deformation of the coaxial cable strain sensor, and has high precision, small error and strong environment adaptability.

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 controls analog data collected by the analog hardware part and converts the analog data into digital data for data processing and data transmission,

the digital hardware part comprises an MCU circuit, a power supply, an ADC circuit, a high-frequency plate circuit, an interface circuit, an inverse voltage circuit, a dial switch, a 485 module and an adder follower circuit, wherein the MCU circuit is respectively in communication connection with the power supply, the ADC circuit, the high-frequency plate circuit, the interface circuit, the inverse voltage circuit, the dial switch, the 485 module and the adder follower circuit;

the analog hardware part comprises a VCO circuit, a power amplifier, a VCO power supply, a filter, a coupler, a mixer, a tapping divider, a phase shifter and a power detector, 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 coupler, the coupler is respectively connected with the mixer, the tapping divider and a microwave switch, the phase shifter is connected between the mixer and the power divider, and the power detector is connected with the microwave switch.

In a preferred embodiment of the invention, the VCO supply generates four power supplies required by the VCO circuit.

In a preferred embodiment of the present invention, the coupler includes a directional coupler and a bidirectional coupler, the directional coupler is connected to the mixer, and the bidirectional coupler is respectively connected to the tap splitter and the microwave switch.

In a preferred embodiment of the present invention, the microwave switch is a six-way microwave switch.

In order to solve the technical problem, the invention adopts another technical scheme that: the demodulation method of the demodulator based on the mixer and the strain sensor of the power detector comprises the following specific steps:

a. initialization

The method comprises the 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 reverse-phase voltage circuit, the dial switch, the 485 module and the adder follower circuit, different task labels are respectively received through a communication protocol, and then an analysis instruction is distributed to the task labels;

c. task execution

And executing the task according to the task tag, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, clearing the task tag after executing the task once, and waiting for updating the next task tag.

The invention has the beneficial effects that: the demodulator and the demodulation method based on the frequency mixer and the power detector strain sensor are used for cable pipeline deformation monitoring, the frequency mixer is used for detecting the phase frequency characteristic of the sensor, the power detector is used for detecting the amplitude frequency characteristic of the sensor, the micro deformation of the coaxial cable strain sensor is calculated, and the demodulator and the demodulation method are high in precision, small in error and strong in environment adaptability.

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 demodulator of the present invention based on a mixer and power detector strain sensor;

FIG. 2 is a schematic diagram of the analog hardware portion of the mixer and power detector strain sensor based demodulator of the present invention;

fig. 3 is a flow chart of the demodulation method of the demodulator based on the strain sensor of the mixer and the power detector.

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 mixer and a power detector strain sensor comprises a digital hardware part and an analog hardware part, wherein the digital hardware part controls analog data collected by the analog hardware part, converts the analog data into digital data, and performs 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, an inverse voltage circuit, a dial switch, a 485 module, and an adder follower circuit, and the MCU circuit is in communication connection with the power supply, the ADC circuit, the high-frequency board circuit, the interface circuit, the inverse voltage circuit, the dial switch, the 485 module, and the adder follower circuit, respectively.

The main device functions are as follows:

the MCU circuit is the core of the digital hardware part, and the main function of the MCU circuit is to coordinate and control the work of each part and carry 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 functions of providing a digital hardware power supply and an analog hardware power supply;

the reverse-phase voltage circuit mainly has the function of providing a negative power supply for the operational amplifier;

the adder follower circuit primarily measures the negative phase produced by the mixer.

The VCO power supply provides power 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, one path of radio frequency signals is output to a local oscillation end of the frequency mixer, the other path of radio frequency signals is output to the sensor, the power divider and the phase shifter to achieve the purpose of phase switching in a matching mode, and the power detector is used for detecting the reflected signal power.

As shown in fig. 2, the analog hardware part includes a VCO circuit, a power amplifier, a VCO power supply, a filter, a coupler, a mixer, an attack divider, a phase shifter and a power detector, 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, the coupler is respectively connected to the mixer, the attack divider and the microwave switch, the phase shifter is connected between the mixer and the power divider, and the power detector is connected to the microwave switch.

The main device functions are as follows:

a VCO circuit: generating a radio frequency signal;

a power detector: detecting the amplitude of the current radio frequency signal;

VCO power supply: generating four paths of power supplies required by the VCO circuit;

a mixer: and mixing the local oscillator end signal and the radio frequency end signal to obtain a high-frequency component and a direct-current component.

Phase measurement principle:

the mixer essentially multiplies the two signals, multiplies the two signals with the same frequency and different phases, obtains a direct current component which is a phase component according to a trigonometric function integration and difference formula, obtains the phase component at the moment by further measuring the phase component after phase shifting by 90 degrees, and obtains the phase component after phase shifting by phase shifting 90 degrees; and dividing the phase components of the previous and subsequent times to normalize the amplitude information to obtain a value of tan theta, and deducing the positive and negative of theta according to the positive and negative of the measured values of the previous and subsequent times.

In the above, the coupler includes a directional coupler and a bidirectional coupler, the directional coupler is connected to the mixer, and the bidirectional coupler is respectively connected to the tapping splitter and the microwave switch.

In this embodiment, the microwave switch adopts a six-way microwave switch.

As shown in fig. 3, the present invention further provides a demodulation method of a demodulator based on a mixer and a strain sensor of a power detector, which comprises the following specific steps:

a. initialization

The method comprises MCU initialization, VCO initialization, external ADC initialization and microwave switch initialization.

An initialization process:

MCU initialization mainly comprises setting the input/output state of MCU circuit pins, the enabling and parameter setting of serial port interruption, the enabling of a timer and the parameter setting of the timer;

vco initialization is mainly to enable the Vco chip and set Vco initial register parameters;

the external ADC initialization mainly comprises enabling an ADC chip and setting SPI bus parameters;

the initialization of the microwave switch is mainly to set an energy microwave switch chip and an initial output channel.

b. Data snooping

The MCU circuit monitors data of the ADC circuit, the high-frequency board circuit, the interface circuit, the reverse-phase voltage circuit, the dial switch, the 485 module and the adder follower circuit respectively, different task labels are received respectively through a communication protocol, and then an analysis instruction distributes the task labels.

When the serial port interruption is triggered, the serial port cache receives data ceaselessly, the serial port data receiving pointer is updated at the same time, when the serial port data receiving pointer is not updated any more, or the serial port data exceeds the set maximum receiving length, the data cached by the serial port is analyzed, an instruction is judged according to the content of a communication protocol, and meanwhile, a task tag is updated according to formulated distribution.

c. Task execution

And executing the task according to the task tag, wherein the task comprises communication instruction analysis, data transmission, data processing and data acquisition, clearing the task tag after executing the task once, and waiting for updating the next task tag.

When the task label is updated, judging which kind of task the task label outputs, processing the task at the moment, and after finishing processing the task for one time, clearing the task label to wait for the next update of the task label.

Wherein the content of the first and second substances,

analyzing a communication command:

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;

each protocol has a corresponding digital unique identifier (control command byte) to determine the instruction content of the protocol according to the byte.

Data transmission:

and transmitting the required data to the upper computer through a 485 bus according to the data transmission instruction.

Data acquisition:

and 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, in the data processing process, filtering algorithm processing is carried out through an ADC circuit, the acquired data is firstly subjected to Fourier frequency domain-time domain transformation to obtain a time domain image, then a sensor section to be measured is selected for windowing processing, then Fourier time domain-frequency domain transformation is carried out to obtain a frequency spectrum image, and then a central maximum peak point is searched in the frequency spectrum image and is used as final data to be stored.

The innovation points of the invention are as follows:

1. detecting the phase-frequency characteristic of the sensor by adopting a mixer;

2. detecting the amplitude-frequency characteristic of the sensor by using a power detector;

3. acquiring a sensor time domain map through fast Fourier transform;

4. 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;

5. 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 mixer and the power detector strain sensor are used for cable pipeline deformation monitoring, the mixer is used for detecting the phase frequency characteristic of the sensor, the power detector is used for detecting the amplitude frequency characteristic of the sensor, the micro deformation of the coaxial cable strain sensor is calculated, and the demodulator and the demodulation method are high in precision, small in error and strong in environment adaptability.

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.