A radio orientation method and device

Abstract

The present invention discloses a radio orientation method. A radio positioning device includes a radio receiver (hereinafter referred to as the receiver), an antenna, a signal generating module, an external crystal oscillator and a signal processing module. The receiver transmits the collected radio signal data to the signal processing module through USB, Ethernet, WIFI, Bluetooth or other communication interfaces (hereinafter collectively referred to as communication interfaces). The signal processing module performs data processing based on MUSIC, ESPRIT, WSF, ISM, a new DOA estimation algorithm based on Bayesian compressed sensing learning or other DOA estimation algorithms (hereinafter collectively referred to as DOA estimation algorithms) to obtain the direction of the signal source and complete orientation. The method disclosed by the present invention improves the efficiency of radio orientation, visualizes the orientation results, simplifies the structure of the orientation device, and can be applied to a variety of working conditions, which is a technical advancement in this field.

Description

Technical Field

[0001] The invention belongs to the field of radio devices, and in particular relates to a method and a device for collecting and locating the same radio signal by using multi-channel receivers with the same frequency. Background Art

[0002] At present, traditional radio direction finding mainly uses directional antennas to measure the direction of arrival to determine the location of the signal source. However, directional antennas have a special structure and often need to be placed externally, which is not conducive to the carrying and use of the device. In order to find the direction of the signal source, it is often necessary to spend a lot of time rotating the directional antenna. After obtaining the signal strength, the direction of the signal source is judged based on this, which seriously reduces the direction finding efficiency. The shortcomings of the prior art: the directional antenna has a special structure and often needs to be placed externally, which is not conducive to the carrying and use of the device. In order to find the direction of the signal source, it is often necessary to spend a lot of time rotating the directional antenna. After obtaining the signal strength, the direction of the signal source is judged based on this, which seriously reduces the direction finding efficiency. Summary of the invention

[0003] In order to overcome the above problems existing in the prior art and products, the present invention discloses a radio orientation method and device, which comprises a receiver, an antenna, a radio frequency switch, a signal generation module, an external crystal oscillator and a signal processing module with the same hardware and software. The receiver transmits the collected radio signal data to the processor through the communication interface, and performs data processing based on the DOA estimation algorithm to obtain the direction of the signal source and complete the orientation. The specific method of radio positioning includes the following steps:

[0004] S1. Connect the first receiver and the second receiver with the same hardware and software to the same crystal oscillator;

[0005] S2. Control the RF switch to connect the first receiver and the second receiver to the signal generating module;

[0006] S3. The first receiver and the second receiver collect the electrical signal emitted by the signal generating module and transmit the IQ data to the signal processing module;

[0007] S4. The signal processing module receives the data and calculates the phase difference between the two signals for calibration;

[0008] S5. Control the RF switch so that the first receiver and the second receiver are connected to the first antenna and the second antenna respectively;

[0009] S6. The first receiver and the second receiver receive the radio signal through the first antenna and the second antenna respectively, collect IQ data, and transmit the data to the signal processing module through the communication interface;

[0010] S7. The signal processing module calculates the angle θ1 between the signal source and the antenna line based on the IQ data of each channel received in step S6 and based on the DOA estimation algorithm.

[0011] Preferably, the receivers in step S1 are all driven by the same crystal oscillator;

[0012] Preferably, the signal generating module in step S2 has the same circuit length when connected to the first receiver and the second receiver;

[0013] Preferably, in the steps S3-S4, the phase difference between the two signals is calculated. If the phase difference is exactly 0, no calibration is required. If the phase difference is not zero, the data of one channel needs to be fixed and the data of the other channel needs to be offset so that the phase difference is 0 degrees. The calibration is completed, and the subsequent orientation needs to compensate the offset to the corresponding radio signal.

[0014] Preferably, the receiver transmits the collected IQ data to the signal processing module via a communication interface, and the communication interface includes: one or more of a USB interface, WIFI, Bluetooth, Ethernet and other communication interfaces;

[0015] Preferably, the step S7 is followed by the following steps:

[0016] S8. Combine the third receiver and the third antenna with the second receiver and the second antenna, and replace the first receiver and the first antenna with the third receiver and the third antenna respectively, and the first antenna, the second antenna and the third antenna are not on the same straight line, repeat the actions of steps S1-S7, calculate the angle θ2 between the signal source and the antenna connection line, combine the angles θ1 and θ2, determine the unique direction angle Φ1 of the signal source, and display the result on the display screen, thereby completing the orientation of the two-dimensional space radio;

[0017] S9. Replace the third receiver and the third antenna with the fourth receiver and the fourth antenna respectively, and combine them with the first receiver, the first antenna, the second receiver, and the second antenna, and the first antenna, the second antenna, the third antenna, and the fourth antenna are not on the same plane, repeat steps S1-S8, and calculate the direction angle Φ2 between the plane where the first antenna, the second antenna, and the fourth antenna are located and the signal source;

[0018] S10. Replace the first receiver with the fourth receiver and the first antenna with the second receiver, the second antenna, the third receiver and the third antenna respectively, repeat steps S1-S8, calculate the direction angle Φ3 between the plane where the second antenna, the third antenna and the fourth antenna are located and the signal source, combine the angles Φ1, Φ2 and Φ3, determine the unique direction of the signal source in the three-dimensional space, and complete the orientation of the three-dimensional space radio.

[0019] Preferably, the signal processing module uses a DOA estimation algorithm to process the received IQ data of each channel, and the DOA estimation algorithm includes: a multiple signal classification (MUSIC) algorithm, a signal parameter estimation based on rotational invariance technology (ESPRIT) algorithm, a weighted subspace fitting (WSF) algorithm, an incoherent signal subspace (ISM) algorithm, and a new DOA estimation algorithm based on Bayesian compressed sensing learning.

[0020] A radio direction-directing device, characterized in that it includes an antenna, a radio frequency switch, a signal generating module, a receiver, a signal processing module, and an external crystal oscillator; the antenna, the receiver, and the radio frequency switch are all in multiple and the number is the same; the antenna is connected to the receiver one-to-one through the radio frequency switch, the radio frequency switch is simultaneously connected to the signal generating module, the external crystal oscillator is respectively connected to the receiver, and the receivers are all connected to the signal processing module.

[0021] Preferably, there are three antennas, three receivers, and three radio frequency switches, and the three antennas are not in the same straight line.

[0022] Preferably, there are four or more antennas, receivers, and radio frequency switches, and all antennas are not on the same plane.

[0023] In two-dimensional radio orientation, the first antenna and the second antenna receive radio signals. The receiver is used to demodulate the IQ data of the specific signal from the received radio signal and transmit it to the signal processing module through the communication interface. The external crystal oscillator provides a unified crystal oscillator signal for the receiver. The signal processing module uses the DOA estimation algorithm to process the received IQ data of each channel and display the calculation results. The signal generation module is used for calibration before orientation. The circuit length from this module to each receiver must be strictly equal.

[0024] Calibration process:

[0025] Even if the receiver hardware and software are exactly the same, it cannot guarantee that the collected signals are time-aligned, so a calibration device is required. Before orientation, the receiver is connected to the signal generation module by controlling the first RF switch and the second RF switch. Each receiver collects the electrical signal emitted by the signal generation module and transmits the IQ data to the signal processing module. The signal processing module receives the data and calculates the phase difference of each signal. Since the circuit length from the signal generation module to each receiver is the same, the phase difference of each signal is theoretically 0. If the phase difference is not 0, it is necessary to fix the data of one channel and offset the data of another channel so that the angle is 0 degrees to complete the calibration. The subsequent orientation needs to compensate the offset to the corresponding signal.

[0026] Orientation process:

[0027] Control the first RF switch and the second RF switch, connect the antenna to the receiver, each receiver receives the wireless signal through the antenna, and collects IQ data, and transmits the data to the signal processing module through the communication interface. The signal processing module receives the IQ data of each channel. Since the device is calibrated in advance, it can be considered that the phase difference of the signal data is the phase difference generated when the carrier is received by the two antennas.

[0028] The phase difference is calculated by the device of the present invention, and the direction is calculated by the phase difference. This process is completed in the signal processing module and included in the DOA estimation algorithm. Figure 5 As shown: the angle between the signal source and the antenna line is θ, the distance between the two antennas is known to be d, the carrier wavelength is λ, and the phase difference is calculated by the device Then θ can be calculated.

[0029]

[0030] This formula is derived from the following two formulas:

[0031]

[0032] Where d is the distance between the two antennas, and r is the projection of d in the direction of the line connecting the signal source and the antenna. Figure 5 shown.

[0033] Although the angle between the signal source and the antenna line is calculated as θ based on the received data of antenna A and antenna B ab However, the specific direction of the signal source cannot be determined, because the signal source may be signal source 1 or signal source 2, as shown in the attached Figure 6 As shown, an additional receiver and antenna C are needed to calculate θ bc ,θ bc It can be determined that the signal source may be signal source 1 or signal source 3. The direction of the signal source can be determined by combining the calculation results of antenna A, antenna B, and antenna C, which is signal source 1.

[0034] Combination angle θ ab ,θ bc , determine the unique direction of the signal source, and display the result on the display screen to complete the two-dimensional space radio orientation. Three-dimensional space radio orientation requires the addition of antenna D and receiver, and ensures that the three-three antennas are not collinear and the four antennas are not coplanar. Calculate the direction of the signal source in each two-dimensional plane to determine the direction of the signal source in three-dimensional space. This orientation method is basically the same as the orientation in two-dimensional space.

[0035] In summary, multiple receivers of the present invention collect the same radio signal, determine the direction of the signal source through the DOA estimation algorithm, improve the efficiency of radio orientation, achieve visual orientation results, simplify the structure of the orientation device, and can be applied to a variety of working conditions, which is a technological advancement in this field. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic diagram of the structure of the two-dimensional plane orientation device in the present invention.

[0037] Figure 2 This is the antenna layout diagram of the two-dimensional planar directional device in the present invention.

[0038] Figure 3 It is a schematic diagram of the structure of the three-dimensional plane orientation device in the present invention.

[0039] Figure 4 This is the antenna layout diagram of the three-dimensional planar directional device in the present invention.

[0040] Figure 5 Schematic diagram of calculating the angle between a two-dimensional plane signal source and an antenna.

[0041] Figure 6 Schematic diagram of the ambiguity of the signal source direction. DETAILED DESCRIPTION

[0042] Embodiment 1:

[0043] The radio positioning method of the present invention comprises the following steps:

[0044] S1. Connect the first receiver 3 and the second receiver 4 to the same external crystal oscillator 7;

[0045] S2 controls the RF switch 8 to connect the first receiver 3 and the second receiver 4 to the signal generating module 5;

[0046] S3. The first receiver 3 and the second receiver 4 collect the electrical signal emitted by the signal generating module 5, and transmit the IQ data to the signal processing module 6 via the USB interface;

[0047] S4. The signal processing module 6 receives the data and calculates the phase difference of each signal for calibration;

[0048] S5. Control the RF switch so that the first receiver 3 and the second receiver 4 are connected to the first antenna 1 and the second antenna 2 respectively;

[0049] S6. The first receiver 3 and the second receiver 4 receive wireless signals through the first antenna 1 and the second antenna 2, respectively, and collect IQ data, and transmit the data to the signal processing module 6 through the communication interface;

[0050] S7. The signal processing module 6 calculates the angle θ1 between the signal source and the line connecting the first antenna 1 and the second antenna 2 based on the IQ data of each channel received in step S5 and the DOA estimation algorithm;

[0051] Furthermore, the receivers in step S1 are all driven by the same crystal oscillator 7;

[0052] Furthermore, the signal generating module 5 in step S2 has the same circuit length when connected to the first receiver 3 and the second receiver 4;

[0053] Furthermore, in step S4, when the calculated phase difference between the two signals is not 0, the data of one channel is fixed and the data of the other channel is offset so that the phase difference is 0, and the calibration is completed. The subsequent orientation needs to compensate the offset to the corresponding radio signal;

[0054] Furthermore, each receiver transmits the collected IQ data to the signal processing module 6 through a communication interface. The communication interface includes: USB interface, WIFI, Bluetooth, Ethernet and other communication interfaces;

[0055] Furthermore, the step S7 is followed by the following steps:

[0056] S8. Combine the third receiver 12 and the third antenna 10 with the second receiver 4 and the second antenna 2, and replace the first receiver 3 and the first antenna 1 with the third receiver and the third antenna, respectively, and the first antenna 1, the second antenna 2, and the third antenna 10 are not on the same straight line. Repeat the actions of steps S1-S7, calculate the angle θ2, combine the angles θ1 and θ2, determine the unique direction angle Φ1 of the signal source, and display the result on the display screen to complete the orientation of the two-dimensional space radio.

[0057] Furthermore, the step S8 is followed by the following steps:

[0058] S9. Combine the fourth receiver 15 and the fourth antenna 13 with the first receiver 3, the first antenna 1, the second receiver 4, and the second antenna 2, and replace the third receiver 12 and the third antenna 10 with the fourth receiver 15 and the fourth antenna 13, respectively, and the first antenna 1, the second antenna 2, the third antenna 10, and the fourth antenna 13 are not on the same plane. Repeat steps S1-S8 to calculate the direction angle Φ2 between the plane where the first antenna 1, the second antenna 2, and the fourth antenna 13 are located and the signal source;

[0059] S10. Combine the fourth receiver 15 and the fourth antenna 13 with the second receiver 4, the second antenna 2, the third receiver 12, and the third antenna 10, and replace the first receiver 3 and the first antenna 1 with the fourth receiver 15 and the fourth antenna 13, respectively, and the first antenna 1, the second antenna 2, the third antenna 10, and the fourth antenna 13 are not on the same plane. Repeat the actions of steps S1-S8 to calculate the direction angle Φ3 between the plane where the second antenna 2, the third antenna 10, and the fourth antenna 13 are located and the signal source. Combine the angles Φ1, Φ2, and Φ3 to determine the unique direction of the signal source in the three-dimensional space, and complete the orientation of the three-dimensional radio.

[0060] Embodiment 2:

[0061] like Figure 1 As shown, the radio direction-directing device in the present invention includes: an antenna, a radio frequency switch, a signal generating module 5, a receiver, a signal processing module 6, and an external crystal oscillator 7; there are three antennas, three receivers, and three radio frequency switches; the first antenna 1 is connected to the first receiver 3 through the first radio frequency switch 8, the second antenna 2 is connected to the second receiver 4 through the second radio frequency switch 9, and the third antenna 10 is connected to the third receiver 12 through the third radio frequency switch 11. The first radio frequency switch 8, the second radio frequency switch 9, and the third radio frequency switch 11 are all connected to the signal generating module 5, and the external crystal oscillator 7 is respectively connected to the first receiver 3, the second receiver 4, and the third receiver 12.

[0062] The positional relationship between the first antenna 1, the second antenna 2 and the third antenna 10 is as follows: Figure 2 The line connecting the first antenna 1 and the second antenna 2 is perpendicular to the line connecting the second antenna 2 and the third antenna 10 .

[0063] The receivers are all RTL-SDR, connected to the same external crystal oscillator, and connected to the signal processing module 6 via a USB interface. The signal processing module 6 is a PC, and the angle between the signal source and the antenna connection can be calculated using the MUSIC algorithm in Matlab. The signal generation module 5 is AD9834, which is used to calibrate the device.

[0064] According to steps S1-S8 in step embodiment 1, the orientation of the two-dimensional planar radio signal source can be completed.

[0065] Embodiment 3:

[0066] An embodiment of the radio orientation device of the present invention for three-dimensional space orientation is as follows Figure 3As shown, it includes: an antenna, a radio frequency switch, a signal generating module 5, a receiver, a signal processing module 6, and an external crystal oscillator 7; there are four antennas, four receivers, and four radio frequency switches; the first antenna 1 is connected to the first receiver 3 through the first radio frequency switch 8, the second antenna 2 is connected to the second receiver 4 through the second radio frequency switch 9, the third antenna 10 is connected to the third receiver 12 through the third radio frequency switch 11, and the fourth antenna 13 is connected to the fourth receiver 15 through the fourth radio frequency switch 14. The first radio frequency switch 8, the second radio frequency switch 9, the third radio frequency switch 11, and the fourth radio frequency switch 14 are all connected to the signal generating module 5, and the external crystal oscillator 7 is respectively connected to the first receiver 3, the second receiver 4, the third receiver 12, and the fourth receiver 15.

[0067] The positional relationship among the first antenna 1, the second antenna 2, the third antenna 10 and the fourth antenna 13 is as follows: Figure 4 The connection line between the first antenna 1 and the second antenna 2, the connection line between the second antenna 2 and the third antenna 10, and the connection line between the fourth antenna 13 and the second antenna 2 are perpendicular to each other.

[0068] The receivers are all RTL-SDR, connected to the same external crystal oscillator, and connected to the signal processing module 6 via a USB interface. The signal processing module 6 is a PC, and the angle between the signal source and the antenna connection can be calculated using the MUSIC algorithm in Matlab. The signal generation module 5 is AD9834, which is used to calibrate the device.

[0069] According to steps S1 to S10 described in Example 1, the orientation of the three-dimensional planar radio signal source can be completed.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A radio orientation method: characterized in that: The following steps are involved: S1. Connect the first receiver and the second receiver with the same hardware and software to the same external crystal oscillator; S2. Control the RF switch to connect the first receiver and the second receiver to the signal generating module; S3. The first receiver and the second receiver collect the electrical signal emitted by the signal generating module and transmit the IQ data to the signal processing module; S4. The signal processing module receives the data and calculates the phase difference between the two signals for calibration; S5. Control the RF switch so that the first receiver and the second receiver are connected to the first antenna and the second antenna respectively; S6. The first receiver and the second receiver receive radio signals through the first antenna and the second antenna respectively, collect IQ data, and transmit the data to the signal processing module through the communication interface; the communication interface includes: one or more of a USB interface, WIFI, Bluetooth, Ethernet and other communication interfaces; S7. The signal processing module calculates the angle θ1 between the signal source and the antenna line based on the IQ data of each channel received in step S6 and the DOA estimation algorithm; The DOA estimation algorithms include: multiple signal classification (MUSIC) algorithm, signal parameter estimation based on rotational invariance technology (ESPRIT) algorithm, weighted subspace fitting (WSF) algorithm, incoherent signal subspace (ISM) algorithm, and a new DOA estimation algorithm based on Bayesian compressed sensing learning; S8. Combine the third receiver and the third antenna with the second receiver and the second antenna, and replace the first receiver and the first antenna with the third receiver and the third antenna respectively, and the first antenna, the second antenna and the third antenna are not on the same straight line, repeat the actions of steps S1-S7, calculate the angle θ2 between the signal source and the antenna connection line, combine the angles θ1 and θ2, determine the unique direction angle Φ1 of the signal source, and display the result on the display screen, thereby completing the orientation of the two-dimensional space radio; S9. Replace the third receiver and the third antenna with the fourth receiver and the fourth antenna respectively, and combine them with the first receiver, the first antenna, the second receiver, and the second antenna, and the first antenna, the second antenna, the third antenna, and the fourth antenna are not on the same plane, repeat steps S1-S8, and calculate the direction angle Φ2 between the plane where the first antenna, the second antenna, and the fourth antenna are located and the signal source; S10. Replace the first receiver and the first antenna with the fourth receiver and the fourth antenna respectively, and combine the second receiver, the second antenna, the third receiver, and the third antenna, and repeat the actions of steps S1-S8, calculate the direction angle Φ3 between the plane where the second antenna, the third antenna, and the fourth antenna are located and the signal source, and combine the angles Φ1, Φ2, and Φ3 to determine the unique direction of the signal source in the three-dimensional space, and complete the orientation of the three-dimensional radio; In the steps S3-S4, the phase difference between the two signals is calculated. If the phase difference is exactly 0, no calibration is required. If the phase difference is not zero, the data of one channel needs to be fixed and the data of the other channel needs to be offset so that the phase difference is 0 degrees. The calibration is completed, and the subsequent orientation needs to compensate the offset to the corresponding radio signal. A radio direction-directing device, comprising an antenna, a radio frequency switch, a signal generating module, a receiver, a signal processing module, and an external crystal oscillator; the antenna, the receiver, and the radio frequency switch are all in a plurality and the number is the same; the antenna is connected to the receiver one-to-one through the radio frequency switch, the radio frequency switch is simultaneously connected to the signal generating module, the external crystal oscillator is respectively connected to the receiver, and the receivers are all connected to the signal processing module; There are three antennas, three receivers, and three radio frequency switches, and the three antennas are not in the same straight line; or there are four or more antennas, three receivers, and three radio frequency switches, and all the antennas are not in the same plane.

2. The radio orientation method according to claim 1, characterized in that: The receivers in step S1 are all driven by the same crystal oscillator.

3. The radio orientation method according to claim 1, characterized in that: The signal generating module in step S2 has the same circuit length when connected to the first receiver and the second receiver.

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