CN106855616A - A kind of alignment system and method based on radio-frequency technique - Google Patents
A kind of alignment system and method based on radio-frequency technique Download PDFInfo
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- CN106855616A CN106855616A CN201611067832.0A CN201611067832A CN106855616A CN 106855616 A CN106855616 A CN 106855616A CN 201611067832 A CN201611067832 A CN 201611067832A CN 106855616 A CN106855616 A CN 106855616A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S5/00—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations
- G01S5/02—Position-fixing by co-ordinating two or more direction or position line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
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- Engineering & Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Position Fixing By Use Of Radio Waves (AREA)
Abstract
The invention provides a kind of alignment system and method based on radio-frequency technique, it is related to RF application.Characterized in that, the system includes：A kind of alignment system based on radio-frequency technique, it is characterised in that the system includes：Directional coupler, phase extraction pretreatment circuit, digital analog converter, radio frequency reception end, radio-frequency transmissions end, oscillator and FPGA；The oscillator signal is connected to radio-frequency transmissions end；Signal is connected to radio frequency reception end respectively at the radio-frequency transmissions end；Signal is connected to radio frequency reception end, phase extraction pretreatment circuit to the directional coupler respectively；The phase extraction pretreatment circuit signal is connected to digital analog converter；The digital analog converter signal is connected to FPGA；The radio frequency reception end signal is connected to FPGA；The radio-frequency transmissions end signal is connected to FPGA.The present invention has the advantages that validity high, good stability and high precision.
Description
Technical field
The present invention relates to radio frequency arts, more particularly to a kind of alignment system and method based on radio-frequency technique.
Background technology
Radio frequency identification (Radio Frequcncy Identification, RFID) is a contactless automatic identification skill
Art, with energy consumption is low, strong adaptability, it is swift to operate many advantages, such as.In recent years, the emphasis of research has turned to hyper band
(UHF, 860~960 MHz), have had scientific research personnel to extract radiofrequency signal and have reached incidence angle or phase difference as RFID positioning
The new direction of research.The feasibility of phase information is extracted in low signal-to-noise ratio actual measurement environment, but does not extract positional information;
Take machine learning training mechanism in the prior art carries out parameter extraction to multiple antennas phase information, but only limits the use of in activity
The less medical treatment tracking of scope.
The content of the invention
In consideration of it, the invention provides a kind of alignment system and method based on radio-frequency technique, the present invention has validity
The advantages of high, good stability and high precision.
The technical solution adopted by the present invention is as follows：
A kind of alignment system based on radio-frequency technique, it is characterised in that the system includes：Directional coupler, phase extraction are pre-
Process circuit, digital analog converter, radio frequency reception end, radio-frequency transmissions end, oscillator and FPGA；The oscillator signal is connected to be penetrated
Frequency transmitting terminal；Signal is connected to radio frequency reception end respectively at the radio-frequency transmissions end；Signal is connected to the directional coupler respectively
Radio frequency reception end, phase extraction pretreatment circuit；The phase extraction pretreatment circuit signal is connected to digital analog converter；It is described
Digital analog converter signal is connected to FPGA；The radio frequency reception end signal is connected to FPGA；The radio-frequency transmissions end signal connection
In FPGA.
The FPA is used to be compiled system, verify, logic control and carries out discrete spectrum correction calculation and positioning
Computing；It includes：Control process device, data transmission unit and memory；Signal is connected to data to the control process device respectively
Transmission unit and memory.
The digital analog converter includes：Bandpass sampling module and D/A converter module；The bandpass sampling module by signal connects
Connect and D/A converter module.
The control process device includes：Codec module, correction verification module and Logic control module；The variation module,
Code treatment is compiled for signal；The correction verification module, for carrying out checking treatment to signal；The Logic control module,
For carrying out logic control treatment to signal.
The system includes power module；Signal is connected to modules in system to the power module respectively, and it includes：
Main power source, auxiliary power and power transfer device；The main power source and auxiliary power, for providing power supply to each submodule in system
Support；Signal is connected to main power source and auxiliary power to the power transfer device respectively, in main power source not enough power supply or failure
In the case of be switched to auxiliary power for system power supply.
A kind of method of the alignment system based on radio-frequency technique, it is characterised in that localization method is comprised the following steps：
Step 1：System and label are communicated, and extract the EPC information of label；
Step 2：System docking is received and the subcarrier signal of transmission is processed, and extracts the phase of the subcarrier signal for receiving and sending
Position is for finding range and positioning；
Step 3：By changing the form of the Single Frequency C W signal that reader sends in tag backscatter information process, will one
The subcarrier signal of low frequency is modulated on CW signals in the way of AM is modulated；
Step 4：For amended CW signals, will send out:The number of delivering letters s (t) and receive signal r (t) carry out respectively bandpass sampling and
Numeric field is sent into after A/D conversions, and the phase of subcarrier component in receiving and transmitting signal is estimated using Discrete Spectrum Correcting Method
QUOTE And QUOTE , the phase difference △ φ of transmitting-receiving subcarrier signal are calculated, if subcarrier frequency is
QUOTE , then the distance between reader and label are represented by：
QUOTE ；
Step 5：By multiple systems to the range measurement of unified label, the positional information that least square method obtains label is carried out,
Obtain final accurate positioning result.
It is described to send and receive signal subcarrier frequency and the determination method of wavelength is：Transmission signal carrier frequency is 915
MHz, its wavelength is 0.3279 m；Initialization system finding range is 0.3~20 m, and 4 carrier cycles are contained in this ranging
Phase, there is phase ambiguity institute；By the way of single-frequency subcarrier amplitude modulation, will a lower frequency subcarrier and carrier modulation,
Using subcarrier as the signal for obtaining phase information；According to finding range, the m of subcarrier wavelength 20, then subcarrier frequency
It is 7.5 MHz；Final selection in this range obtains subcarrier frequency for 2 MHz, secondary for the measurement distance of 0.3~20 m
The phase place change scope of carrier wave is 1.44 °~96 °.
Using above technical scheme, present invention produces following beneficial effect：
1st, strong applicability：Alignment system of the invention is sent out based on phase shift rangefinder, under bandpass sampling mode, with reference to discrete spectrum
Phase calibration estimation, has carried out location simulation, compared to existing localization method, possesses applicability higher, incessantly in activity
It is applicable in the case of scope is less, is equally applicable to the larger situation of scope of activities.
2nd, accurate positioning：Alignment system of the invention is corrected to result, improves the accuracy of result；Meanwhile,
The data message obtained using multiple independent systems is positioned to target labels, improves the accuracy of positioning result.
3rd, good stability：Alignment system excellent stability of the invention, have chosen the pair of the frequency and wavelength being adapted to the most
Carrier wave, improves the stability of system.
4：Validity is high：Alignment system validity of the invention is high, and the data that each system is obtained possess and higher have
Effect property, eliminates invalid data message.
Brief description of the drawings
Fig. 1 is the system structure diagram of a kind of alignment system and method based on radio-frequency technique of the invention.
Specific embodiment
All features disclosed in this specification, or disclosed all anti-tumble methods or during the step of, except mutual
Beyond the feature and/or step mutually repelled, can combine by any way.
This specification（Including any accessory claim, summary）Disclosed in any feature, unless specifically stated otherwise,
Equivalent by other or with similar purpose alternative features are replaced.I.e., unless specifically stated otherwise, each feature is a series of
An example in equivalent or similar characteristics.
A kind of alignment system based on radio-frequency technique is provided in the embodiment of the present invention 1, system architecture is as shown in Figure 1：
A kind of alignment system based on radio-frequency technique, it is characterised in that the system includes：Directional coupler, phase extraction are pre-
Process circuit, digital analog converter, radio frequency reception end, radio-frequency transmissions end, oscillator and FPGA；The oscillator signal is connected to be penetrated
Frequency transmitting terminal；Signal is connected to radio frequency reception end respectively at the radio-frequency transmissions end；Signal is connected to the directional coupler respectively
Radio frequency reception end, phase extraction pretreatment circuit；The phase extraction pretreatment circuit signal is connected to digital analog converter；It is described
Digital analog converter signal is connected to FPGA；The radio frequency reception end signal is connected to FPGA；The radio-frequency transmissions end signal connection
In FPGA.
The FPA is used to be compiled system, verify, logic control and carries out discrete spectrum correction calculation and positioning
Computing；It includes：Control process device, data transmission unit and memory；Signal is connected to data to the control process device respectively
Transmission unit and memory.
The digital analog converter includes：Bandpass sampling module and D/A converter module；The bandpass sampling module by signal connects
Connect and D/A converter module.
The control process device includes：Codec module, correction verification module and Logic control module；The variation module,
Code treatment is compiled for signal；The correction verification module, for carrying out checking treatment to signal；The Logic control module,
For carrying out logic control treatment to signal.
The system includes power module；Signal is connected to modules in system to the power module respectively, and it includes：
Main power source, auxiliary power and power transfer device；The main power source and auxiliary power, for providing power supply to each submodule in system
Support；Signal is connected to main power source and auxiliary power to the power transfer device respectively, in main power source not enough power supply or failure
In the case of be switched to auxiliary power for system power supply.
A kind of localization method based on radio-frequency technique is provided in the embodiment of the present invention 2：
A kind of method of the alignment system based on radio-frequency technique, it is characterised in that localization method is comprised the following steps：
Step 1：System and label are communicated, and extract the EPC information of label；
Step 2：System docking is received and the subcarrier signal of transmission is processed, and extracts the phase of the subcarrier signal for receiving and sending
Position is for finding range and positioning；
Step 3：By changing the form of the Single Frequency C W signal that reader sends in tag backscatter information process, will one
The subcarrier signal of low frequency is modulated on CW signals in the way of AM is modulated；
Step 4：For amended CW signals, will send out:The number of delivering letters s (t) and receive signal r (t) carry out respectively bandpass sampling and
Numeric field is sent into after A/D conversions, and the phase of subcarrier component in receiving and transmitting signal is estimated using Discrete Spectrum Correcting Method
QUOTE And QUOTE , the phase difference △ φ of transmitting-receiving subcarrier signal are calculated, if subcarrier frequency is
QUOTE , then the distance between reader and label are represented by：
QUOTE ；
Step 5：By multiple systems to the range measurement of unified label, the positional information that least square method obtains label is carried out,
Obtain final accurate positioning result.
It is described to send and receive signal subcarrier frequency and the determination method of wavelength is：Transmission signal carrier frequency is 915
MHz, its wavelength is 0.3279 m；Initialization system finding range is 0.3~20 m, and 4 carrier cycles are contained in this ranging
Phase, there is phase ambiguity institute；By the way of single-frequency subcarrier amplitude modulation, will a lower frequency subcarrier and carrier modulation,
Using subcarrier as the signal for obtaining phase information；According to finding range, the m of subcarrier wavelength 20, then subcarrier frequency
It is 7.5 MHz；Final selection in this range obtains subcarrier frequency for 2 MHz, secondary for the measurement distance of 0.3~20 m
The phase place change scope of carrier wave is 1.44 °~96 °.
A kind of alignment system and method based on radio-frequency technique, system architecture such as Fig. 1 institutes are provided in the embodiment of the present invention 3
Show：
A kind of alignment system based on radio-frequency technique, it is characterised in that the system includes：Directional coupler, phase extraction are pre-
Process circuit, digital analog converter, radio frequency reception end, radio-frequency transmissions end, oscillator and FPGA；The oscillator signal is connected to be penetrated
Frequency transmitting terminal；Signal is connected to radio frequency reception end respectively at the radio-frequency transmissions end；Signal is connected to the directional coupler respectively
Radio frequency reception end, phase extraction pretreatment circuit；The phase extraction pretreatment circuit signal is connected to digital analog converter；It is described
Digital analog converter signal is connected to FPGA；The radio frequency reception end signal is connected to FPGA；The radio-frequency transmissions end signal connection
In FPGA.
The FPA is used to be compiled system, verify, logic control and carries out discrete spectrum correction calculation and positioning
Computing；It includes：Control process device, data transmission unit and memory；Signal is connected to data to the control process device respectively
Transmission unit and memory.
The digital analog converter includes：Bandpass sampling module and D/A converter module；The bandpass sampling module by signal connects
Connect and D/A converter module.
The control process device includes：Codec module, correction verification module and Logic control module；The variation module,
Code treatment is compiled for signal；The correction verification module, for carrying out checking treatment to signal；The Logic control module,
For carrying out logic control treatment to signal.
The system includes power module；Signal is connected to modules in system to the power module respectively, and it includes：
Main power source, auxiliary power and power transfer device；The main power source and auxiliary power, for providing power supply to each submodule in system
Support；Signal is connected to main power source and auxiliary power to the power transfer device respectively, in main power source not enough power supply or failure
In the case of be switched to auxiliary power for system power supply.
A kind of method of the alignment system based on radio-frequency technique, it is characterised in that localization method is comprised the following steps：
Step 1：System and label are communicated, and extract the EPC information of label；
Step 2：System docking is received and the subcarrier signal of transmission is processed, and extracts the phase of the subcarrier signal for receiving and sending
Position is for finding range and positioning；
Step 3：By changing the form of the Single Frequency C W signal that reader sends in tag backscatter information process, will one
The subcarrier signal of low frequency is modulated on CW signals in the way of AM is modulated；
Step 4：For amended CW signals, will send out:The number of delivering letters s (t) and receive signal r (t) carry out respectively bandpass sampling and
Numeric field is sent into after A/D conversions, and the phase of subcarrier component in receiving and transmitting signal is estimated using Discrete Spectrum Correcting Method
QUOTE And QUOTE , the phase difference △ φ of transmitting-receiving subcarrier signal are calculated, if subcarrier frequency is
QUOTE , then the distance between reader and label are represented by：
QUOTE ；
Step 5：By multiple systems to the range measurement of unified label, the positional information that least square method obtains label is carried out,
Obtain final accurate positioning result.
It is described to send and receive signal subcarrier frequency and the determination method of wavelength is：Transmission signal carrier frequency is 915
MHz, its wavelength is 0.3279 m；Initialization system finding range is 0.3~20 m, and 4 carrier cycles are contained in this ranging
Phase, there is phase ambiguity institute；By the way of single-frequency subcarrier amplitude modulation, will a lower frequency subcarrier and carrier modulation,
Using subcarrier as the signal for obtaining phase information；According to finding range, the m of subcarrier wavelength 20, then subcarrier frequency
It is 7.5 MHz；Final selection in this range obtains subcarrier frequency for 2 MHz, secondary for the measurement distance of 0.3~20 m
The phase place change scope of carrier wave is 1.44 °~96 °.
The invention is not limited in foregoing specific embodiment.The present invention is expanded to and any in this manual disclosed
New feature or any new combination, and disclose any new anti-tumble method or process the step of or any new combination.
Claims (7)
1. a kind of alignment system based on radio-frequency technique, it is characterised in that the system includes：Directional coupler, phase extraction
Pretreatment circuit, digital analog converter, radio frequency reception end, radio-frequency transmissions end, oscillator and FPGA；The oscillator signal is connected to
Radio-frequency transmissions end；Signal is connected to radio frequency reception end respectively at the radio-frequency transmissions end；The directional coupler difference signal connection
In radio frequency reception end, phase extraction pretreatment circuit；The phase extraction pretreatment circuit signal is connected to digital analog converter；Institute
State digital analog converter signal and be connected to FPGA；The radio frequency reception end signal is connected to FPGA；The radio-frequency transmissions end signal connects
It is connected to FPGA.
2. the alignment system of radio-frequency technique is based on as claimed in claim 1, it is characterised in that the FPA is used to enter system
Row compiling, verification, logic control and carry out discrete spectrum correction calculation and positions calculations；It includes：Control process device, data
Transmission unit and memory；Signal is connected to data transmission unit and memory to the control process device respectively.
3. the alignment system of radio-frequency technique is based on as claimed in claim 1 or 2, it is characterised in that the digital analog converter bag
Include：Bandpass sampling module and D/A converter module；The bandpass sampling module by signal connection and D/A converter module.
4. the alignment system of radio-frequency technique is based on as claimed in claim 1 or 2, it is characterised in that the control process device bag
Include：Codec module, correction verification module and Logic control module；The variation module, code treatment is compiled for signal；Institute
Correction verification module is stated, for carrying out checking treatment to signal；The Logic control module, for being carried out at logic control to signal
Reason.
5. the alignment system of radio-frequency technique is based on as claimed in claim 1 or 2, it is characterised in that the system includes power supply
Module；Signal is connected to modules in system to the power module respectively, and it includes：The switching of main power source, auxiliary power and power supply
Device；The main power source and auxiliary power, support for providing power supply to each submodule in system；The power transfer device point
Level signal is connected to main power source and auxiliary power, for being switched to auxiliary power to be in the case of main power source not enough power supply or failure
System power supply.
6. a kind of method of the alignment system based on radio-frequency technique described based on one of claim 1 to 5, it is characterised in that
Localization method is comprised the following steps：
Step 1：System and label are communicated, and extract the EPC information of label；
Step 2：System docking is received and the subcarrier signal of transmission is processed, and extracts the phase of the subcarrier signal for receiving and sending
Position is for finding range and positioning；
Step 3：By changing the form of the Single Frequency C W signal that reader sends in tag backscatter information process, will one
The subcarrier signal of low frequency is modulated on CW signals in the way of AM is modulated；
Step 4：For amended CW signals, will send out:The number of delivering letters s (t) and receive signal r (t) carry out respectively bandpass sampling and
Numeric field is sent into after A/D conversions, and the phase of subcarrier component in receiving and transmitting signal is estimated using Discrete Spectrum Correcting MethodWith
, the phase difference △ φ of transmitting-receiving subcarrier signal are calculated, if subcarrier frequency is, then the distance between reader and label
It is represented by：
；
Step 5：By multiple systems to the range measurement of unified label, the positional information that least square method obtains label is carried out,
Obtain final accurate positioning result.
7. the localization method of the alignment system based on radio-frequency technique as claimed in claim 6, it is characterised in that the transmission and
The determination method for receiving signal subcarrier frequency and wavelength is：Transmission signal carrier frequency is 915 MHz, and its wavelength is
0.3279 m；Initialization system finding range is 0.3~20 m, and 4 carrier cycles are contained in this ranging, there is phase ambiguity
Institute；By the way of single-frequency subcarrier amplitude modulation, will a lower frequency subcarrier and carrier modulation, using subcarrier as obtaining
Take the signal of phase information；According to finding range, the m of subcarrier wavelength 20, then subcarrier frequency is 7.5 MHz；Finally exist
Selection obtains subcarrier frequency for 2 MHz in the scope, for the measurement distance of 0.3~20 m, the phase place change model of subcarrier
Enclose is 1.44 °~96 °.
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| CN201611067832.0A CN106855616A (en) | 2016-11-29 | 2016-11-29 | A kind of alignment system and method based on radio-frequency technique |
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Cited By (1)
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| CN108710121A (en) * | 2018-05-30 | 2018-10-26 | 佛山市顺德区中山大学研究院 | A kind of kNN fingerprinting localization algorithms based on phase difference |
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| CN101089654A (en) * | 2007-07-17 | 2007-12-19 | 天津大学 | RFID wireless positioning method based on phase difference ranging |
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Application publication date: 20170616 |