TWI756122B - Distance Doppler Radar Angle Sensing Method and Device - Google Patents

Abstract

A range Doppler angle sensing method comprises a range Doppler radar angle sensing device, and includes the following steps: receiving a first sensing signal and a second sensing signal, These signals respectively first perform a one-dimensional (1D) fast Fourier transform (Fast Fourier Transform; FFT) and then perform a two-dimensional (2D) FFT, so as to calculate at least a first 2D fast Fourier transform map and at least a first Two 2D fast Fourier transform maps; according to a given Doppler index, a first feature column is selected from the at least one first 2D fast Fourier transform map and a first feature column is selected from the at least one second 2D fast Fourier transform In the figure, a second feature column is selected to perform a three-dimensional (3D) FFT calculation to obtain a distance Doppler radar angle, which reduces the computational burden generated by a gesture recognition function.

Description

Distance Doppler Radar Angle Sensing Method and Device

A radar angle sensing method and device, especially a range Doppler angle sensing method and device.

A Doppler radar gesture recognition system is a conventional gesture recognition system. The Doppler radar gesture recognition system can sense the movement, shape, and posture of the user's hand, and generate a range Doppler image (Range Doppler Image; RDI). The Doppler radar gesture recognition system usually uses a one-dimensional (1D) fast Fourier transform (Fast Fourier Transform; FFT) to sense a distance of an object, and uses a two-dimensional (2D) fast Fourier transform to sense A velocity of the object is measured, and a radar angle of the object is sensed with a three-dimensional (3D) fast Fourier transform.

The Doppler radar gesture recognition system can be used in combination with a smart phone or a smart device such as a smart panel, and the Doppler radar gesture recognition system can use a processor of the smart device to recognize A plurality of gesture sensing signals and to distinguish a user action. The smart device can perform multiple functions according to the identified user actions. For example, the smart device can sense a user's action and unlock the smart device when the action is consistent with a known user action. .

However, the 3D fast Fourier transform is computationally complex, and the above-mentioned gesture recognition function is only one of the functions of the smart device. When computing the gesture recognition function creates a huge system burden on the smart device, the general functions of the smart device will be affected in operation.

Therefore, the Doppler radar gesture recognition system needs to improve its working efficiency so as to have more space to be used.

In view of the above problems, the present invention provides a range Doppler angle sensing method and a range Doppler angle sensing device. The present invention can reduce the computational burden of a gesture recognition function on a system.

The distance Doppler radar angle sensing method includes the following steps:

receiving a first sensing signal and a second sensing signal;

performing a one-dimensional (1D) fast Fourier transform (Fast Fourier Transform; FFT) on the first sensing signal to calculate a complex first 1D fast Fourier transform map (FFT map);

performing a two-dimensional (2D) FFT on the first 1D fast Fourier transform maps to calculate at least one first 2D fast Fourier transform map;

performing a 1D FFT on the second sensing signal to calculate a complex second 1D fast Fourier transform map;

performing a 2D FFT on the second 1D fast Fourier transform maps to calculate at least one second 2D fast Fourier transform map;

A first feature column is selected from the at least one first 2D FFT map and a second feature is selected from the at least one second 2D FFT map according to a given Doppler index column;

performing a three-dimensional (3D) FFT on the first feature column of the at least one first 2D fast Fourier transform map and the second feature column of the at least one second 2D fast Fourier transform map to obtain a distance ler radar angle.

In addition, the distance Doppler radar angle sensing device includes a transmitting unit, a first sensing unit, a second sensing unit and a processing unit. The transmitting unit sends out a check signal. The first sensing unit senses a first sensing signal, and the second sensing unit senses a second sensing signal. The processing unit is electrically connected to the transmitting unit, the first sensing unit and the second sensing unit.

The processing unit receives the first sensing signal from the first sensing unit and the second sensing signal from the second sensing unit, and performs a one-dimensional (1D) fast Fourier transform on the first sensing signal Transform (Fast Fourier Transform; FFT) to calculate complex first 1D FFT maps, and perform a two-dimensional (2D) FFT on the first 1D FFT maps to calculate at least one first 2D Fast Fourier Transform plot.

Then, the processing unit performs a 1D FFT on the second sensing signal to calculate a complex second 1D fast Fourier transform map, and performs a 2D FFT on the second 1D fast Fourier transform maps to calculate at least one first Two 2D fast Fourier transform graphs.

The processing unit further selects a first feature column from the at least one first 2D FFT map and selects a first feature column from the at least one second 2D FFT map according to a given Doppler index a second feature bar, and performing a three-dimensional (3D) FFT on the first feature bar of the at least one first 2D fast Fourier transform map and the second feature bar of the at least one second 2D fast Fourier transform map to derive a distance Doppler radar angle.

The present invention only performs a 3D FFT on the selected first feature column and the selected second feature column, but does not perform a 3D FFT on the first 2D fast Fourier transform map and the second 2D fast Fourier transform map All the values are subjected to a 3D FFT. Therefore, the present invention can reduce the computational burden of the gesture recognition function on a system.

Please refer to FIG. 1 and FIG. 2 , the present invention is a range Doppler angle sensing method and a range Doppler angle sensing device.

The distance Doppler radar angle sensing method includes the following steps:

Step S101 : receiving a first sensing signal and a second sensing signal;

Step S102 : perform a one-dimensional (1D) fast Fourier transform (Fast Fourier Transform; FFT) on the first sensing signal to calculate a complex first 1D fast Fourier transform (FFT map);

Step S103: perform a two-dimensional (2D) FFT on the first 1D fast Fourier transform maps to calculate at least one first 2D fast Fourier transform map;

Step S104: performing a 1D FFT on the second sensing signal to calculate a complex second 1D fast Fourier transform map;

Step S105: perform a 2D FFT on the second 1D fast Fourier transform maps to calculate at least one second 2D fast Fourier transform map;

Step S106: According to a given Doppler index (Doppler index), a first feature column is selected from the at least one first 2D FFT map and a first feature column is selected from the at least one second 2D FFT map. The second characteristic column;

Step S107: Perform a three-dimensional (3D) FFT on the first characteristic column of the at least one first 2D fast Fourier transform map and the second characteristic column of the at least one second 2D fast Fourier transform map to obtain a Distance Doppler radar angle.

In addition, the distance Doppler radar angle sensing device includes a transmitting unit 10, a first sensing unit 21, a second sensing unit 22 and a processing unit 30, wherein the processing unit 30 is electrically connected to the transmitting unit 10. The first sensing unit 21 and the second sensing unit 22 . The transmitting unit 10 sends out a check signal. The first sensing unit 21 senses a first sensing signal, and the second sensing unit 22 senses a second sensing signal.

The processing unit 30 receives the first sensing signal from the first sensing unit 21 and the second sensing signal from the second sensing unit 22, and then performs a one-dimensional (1D) ) of the Fast Fourier Transform (FFT) to calculate complex first 1D FFT maps, and perform a two-dimensional (2D) FFT on the first 1D FFT maps to calculate at least A first 2D fast Fourier transform map.

The processing unit 30 also performs a 1D FFT on the second sensing signal to calculate a complex second 1D fast Fourier transform map, and performs a 2D FFT on the second 1D fast Fourier transform maps to calculate at least one second 2D Fast Fourier Transform plot.

The processing unit 30 further selects a first feature column from the at least one first 2D FFT map and selects a first feature column from the at least one second 2D FFT map according to a given Doppler index A second feature bar is generated, and a three-dimensional (3D) analysis is performed on the first feature bar of the at least one first 2D fast Fourier transform map and the second feature bar of the at least one second 2D fast Fourier transform map FFT to derive a range Doppler radar angle.

Because the present invention only performs a 3D FFT on the selected first feature column and the selected second feature column, the first 2D fast Fourier transform map and the second 2D fast Fourier transform map are not All the values in the 3D FFT are performed as a 3D FFT. Therefore, the present invention can reduce the computational burden of the gesture recognition function on a system.

Please refer to FIG. 3 , in detail, the method for sensing a distance Doppler radar angle further includes the following steps in step S107:

Step S301: make the first characteristic column of the at least one first 2D fast Fourier transform map become a first column in a transformation map;

Step S302: make the second characteristic column of the at least one second 2D fast Fourier transform map become a second column in the transformation map;

Step S303: Fill 0 into the remaining fields in the conversion diagram;

Step S304: perform a 3D FFT on the transform map to calculate a radar angle fast Fourier transform map;

Step S305: Use a Coordinate Rotation Digital Computer (CORDIC) on the radar angle FFT map to obtain the range Doppler radar angle.

Referring to FIG. 4 , for example, it is assumed that the at least one first 2D fast Fourier transform map and the at least one second 2D fast Fourier transform map are each a 32*32 map, that is, the at least one first 2D fast Fourier transform map is A 2D fast Fourier transform map and the at least one second 2D fast Fourier transform map each contain 32 columns and 32 columns, and each contains 32*32 values.

When the Doppler index is 0, the first column of the at least one first 2D fast Fourier transform map and the first column of the at least one second 2D fast Fourier transform map will be selected, that is, the at least one The first column of the first 2D fast Fourier transform map is the first characteristic column, and the first column of the at least one second 2D fast Fourier transform map is the second characteristic column. Then, the selected fields will be correspondingly set in the conversion map. For example, the first characteristic field is correspondingly set in the conversion map, becoming the first field in the conversion map, and the second characteristic field in the conversion map. Correspondingly set to the conversion diagram, and become the second column in the conversion diagram. Because the conversion diagram is also a 32*32 diagram, the remaining fields in the conversion diagram, that is, the fields from the 3rd column to the 32nd column in the conversion diagram, will be filled with the number 0. In other words, a total of 32*30 number 0's will correspond to 32 rows and 30 columns of number 0's to fill in the columns from column 3 to column 32 in the conversion diagram.

Each row of the transform map is further subjected to 3D FFT processing to calculate the radar angle FFT map, and a coordinate rotation digital computer (CORDIC) is used for the radar angle FFT map to obtain the distance. Doppler radar angle.

In an embodiment of the present invention, the processing unit 30 of the range Doppler radar angle sensing apparatus executes the range Doppler radar angle sensing method. In this embodiment, the given Doppler index is 0, so that the first characteristic column of the at least one first 2D fast Fourier transform map becomes a first column in a transform map, and the at least one second 2D The second characteristic column of the fast Fourier transform map becomes a second column of the transform map. In addition, in this embodiment, the first sensing signal and the second sensing signal come from different sensing chains, and the first sensing signal and the second sensing signal are a frequency modulated continuous wave (Frequency Modulated Continuous Wave). Continuous Waveform; FMCW) signal.

In this embodiment, the transmitting unit 10 is an FMCW transmitter, and the first sensing unit 21 and the second sensing unit 22 are each an FMCW receiver. In other words, in this embodiment, the first sensing unit 21 is a first sensing chain, and the second sensing unit 22 is a second sensing chain different from the first sensing chain. In this embodiment, the processing unit 30 is a central processing unit (Central Processing Unit; CPU) of a smart phone.

Because the processing unit 30 only performs a 3D FFT on a transformed map, and the transformed map only contains the first feature column of the at least one first 2D fast Fourier transform map, the at least one second 2D fast Fourier transform map With this second characteristic field of the Fourier transform map and the remaining fields filled with the number 0, computing the FFT of the 3D of the transform map will be very simple. Therefore, the present invention can reduce the computational burden caused by the gesture recognition function to the system of a smart device, so that the general functions of the smart device will not be affected in operation.

Although this specification refers to the forward-looking plural features and advantages of the present invention, as well as the detailed structure and function of the present invention, the disclosed information in this specification is merely an illustration. That is to say, changes in details such as changing the shape, changing the size, or reorganizing the structure are allowed within the scope of the present invention, and the scope of the present invention is the scope of patent protection contained in the text of the claims of the present invention.

10: Launch unit 21: The first sensing unit 22: The second sensing unit 30: Processing unit S101~S107: Steps S301~S305: Steps

FIG. 1 is a flowchart of a method for sensing a range Doppler angle according to the present invention. FIG. 2 is a system block diagram of a range Doppler angle sensing device according to the present invention. FIG. 3 is another flow chart of the method for sensing the angle of the distance Doppler radar according to the present invention. 4 is a diagram of the present invention performing a three-dimensional (3D) fast Fourier transform on the first feature bar of the at least one first 2D fast Fourier transform map and the second feature bar of the at least one second 2D fast Fourier transform map (Fast Fourier Transform; FFT) schematic.

S101~S107: Steps

Claims (13)

A distance Doppler radar angle sensing method, comprising the following steps: receiving a first sensing signal and a second sensing signal; performing a one-dimensional (1D) fast Fourier transform (Fast Fourier Transform; FFT) on the first sensing signal to calculate a complex first 1D fast Fourier transform map (FFT map); performing a two-dimensional (2D) FFT on the first 1D fast Fourier transform maps to calculate at least one first 2D fast Fourier transform map; performing a 1D FFT on the second sensing signal to calculate a complex second 1D fast Fourier transform map; performing a 2D FFT on the second 1D fast Fourier transform maps to calculate at least one second 2D fast Fourier transform map; A first feature column is selected from the at least one first 2D FFT map and a second feature is selected from the at least one second 2D FFT map according to a given Doppler index column; performing a three-dimensional (3D) FFT on the first feature column of the at least one first 2D fast Fourier transform map and the second feature column of the at least one second 2D fast Fourier transform map to obtain a distance ler radar angle. The distance Doppler radar angle sensing method as claimed in claim 1, wherein the first characteristic column of the at least one first 2D fast Fourier transform map and the first characteristic column of the at least one second 2D fast Fourier transform map The step of performing a three-dimensional (3D) FFT to obtain a range Doppler radar angle further includes the following steps: making the first feature column of the at least one first 2D fast Fourier transform map a first column in a transform map; making the second characteristic column of the at least one second 2D fast Fourier transform map a second column in the transform map; Fill in 0 in the remaining fields of the conversion diagram; performing a 3D FFT on the transform map to calculate a radar angle fast Fourier transform map; A Coordinate Rotation Digital Computer (CORDIC) is used for the radar angle FFT map to derive the range Doppler radar angle. The distance Doppler radar angle sensing method as claimed in claim 1, wherein the given Doppler index is 0. The distance Doppler radar angle sensing method as claimed in claim 1, wherein the first characteristic column is the first column of the at least one first 2D fast Fourier transform map; and The second characteristic column is the first column of the at least one second 2D fast Fourier transform map. The distance Doppler radar angle sensing method as claimed in claim 1, wherein the first sensing signal and the second sensing signal come from different sensing chains. The distance Doppler radar angle sensing method according to claim 1, wherein the first sensing signal and the second sensing signal are a Frequency Modulated Continuous Wave (FMCW) signal. A distance Doppler radar angle sensing device, comprising: a transmitting unit, which sends out a check signal; a first sensing unit for sensing a first sensing signal; a second sensing unit for sensing a second sensing signal; a processing unit electrically connected to the transmitting unit, the first sensing unit and the second sensing unit; Wherein, the processing unit receives the first sensing signal from the first sensing unit and the second sensing signal from the second sensing unit, and then performs a one-dimensional (1D) on the first sensing signal The fast Fourier transform (Fast Fourier Transform; FFT) to calculate the complex first 1D fast Fourier transform map (FFT map), and perform a two-dimensional (2D) FFT on the first 1D fast Fourier transform map to calculate at least one a first 2D fast Fourier transform map; The processing unit also performs a 1D FFT on the second sensing signal to calculate a complex second 1D fast Fourier transform map, and performs a 2D FFT on the second 1D fast Fourier transform maps to calculate at least one first Two 2D fast Fourier transform maps; The processing unit further selects a first feature column from the at least one first 2D FFT map and selects a first feature column from the at least one second 2D FFT map according to a given Doppler index. Picking out a second feature bar and performing a three-dimensional (3D) on the first feature bar of the at least one first 2D fast Fourier transform map and the second feature bar of the at least one second 2D fast Fourier transform map FFT to derive a distance from the Doppler radar angle. The distance Doppler radar angle sensing device of claim 7, wherein the distance is obtained when the processing unit performs a three-dimensional (3D) FFT on the first characteristic column and the second characteristic column Doppler radar angle, the processing unit makes the first characteristic column a first column in a conversion diagram, and makes the second characteristic column a second column in the conversion diagram, and then fills in 0 In the remaining fields of the conversion map, a 3D FFT is performed on the conversion map to calculate a radar angle FFT map, and a Coordinate Rotation Digital Computer is used for the radar angle FFT map. ; CORDIC) to derive the distance Doppler radar angle. The distance Doppler radar angle sensing device as claimed in claim 7, wherein the given Doppler index is 0. The distance Doppler radar angle sensing device of claim 7, wherein the first characteristic column is a first column of the at least one first 2D fast Fourier transform map; and The second characteristic column is the first column of the at least one second 2D fast Fourier transform map. The distance Doppler radar angle sensing device of claim 7, wherein the first sensing unit is a first sensing chain, and the second sensing unit is different from the first sensing chain a second sense chain. The distance Doppler radar angle sensing device of claim 7, wherein the transmitting unit is a Frequency Modulated Continuous Wave (FMCW) transmitter; and Wherein, the first sensing unit and the second sensing unit are each an FMCW receiver. The distance Doppler radar angle sensing device according to claim 7, wherein the processing unit is a central processing unit (CPU) of a smart phone.

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