阅读说明：本技术 移动物体侦测电路及移动物体侦测方法 (Moving object detection circuit and moving object detection method ) 是由 纪翔峰 于 2019-03-07 设计创作，主要内容包括：一种移动物体侦测电路,用以侦测受测物体的移动信息,包括混合电路、模拟数字转换电路、混合单元及距离侦测单元。该混合电路将高频载波信号及第一模拟信号混频以产生第二模拟信号。该第一模拟信号是根据发射信号被该受测物体反射而产生。该模拟数字转换电路根据该第二模拟信号产生数字信号。该混合单元将第一中频参考信号与第二中频参考信号混合关于该数字信号的中间信号,以分别产生第一信号及第二信号。该距离侦测单元根据该第一信号与该第二信号产生侦测值。该侦测值是对应于该受测物体及该移动物体侦测电路之间的距离。(A moving object detection circuit is used for detecting moving information of a detected object and comprises a mixing circuit, an analog-digital conversion circuit, a mixing unit and a distance detection unit. The mixing circuit mixes the high frequency carrier signal and the first analog signal to generate a second analog signal. The first analog signal is generated according to the reflection of the emission signal by the tested object. The analog-digital conversion circuit generates a digital signal according to the second analog signal. The mixing unit mixes the first intermediate frequency reference signal and the second intermediate frequency reference signal with respect to the intermediate signal of the digital signal to generate a first signal and a second signal, respectively. The distance detection unit generates a detection value according to the first signal and the second signal. The detection value corresponds to a distance between the object to be detected and the moving object detection circuit.)

1. A moving object detection circuit for detecting movement information of a detected object, comprising:

a first mixing circuit for mixing a high frequency carrier signal with a first analog signal to generate a second analog signal,

Wherein the first analog signal is generated according to a transmission signal reflected by the object to be measured;

an analog-to-digital conversion circuit coupled to the first hybrid circuit for generating at least one first digital signal according to the second analog signal;

a first mixing unit for mixing an intermediate signal and a first and a second intermediate frequency reference signal to generate a first and a second signal, respectively, wherein the first and the second intermediate frequency reference signals are related to an intermediate frequency, and the intermediate signal is related to the at least one first digital signal; and

a distance detecting unit for generating a detection value according to the first signal and the second signal, wherein the detection value corresponds to a distance between the detected object and the moving object detecting circuit;

wherein, this distance detecting element includes:

A time-to-frequency domain analysis unit for generating at least one frequency domain signal according to the first signal and the second signal; and

A spectrum peak analysis unit for selecting a spectrum peak according to the at least one frequency domain signal to generate a calculated value,

Wherein the calculated value is related to the detected value.

2. the moving object detection circuit of claim 1, wherein the first mixing unit comprises:

A first complex multiplication unit for performing complex multiplication operation on the first intermediate frequency reference signal, the second intermediate frequency reference signal and the intermediate signal to generate the first signal; and

A second complex multiplication unit for performing complex multiplication operation on the first intermediate frequency reference signal, the second intermediate frequency reference signal and the intermediate signal to generate the second signal;

The intermediate signal includes the first digital signal and a second digital signal.

3. The moving object detection circuit of claim 2, wherein:

The time domain to frequency domain analysis unit comprises:

a first Fourier transform unit for performing Fourier transform on the first signal to generate a first frequency-domain signal;

and

A second Fourier transform unit for performing Fourier transform on the second signal to generate a second frequency-domain signal.

4. the moving object detection circuit of claim 3, wherein:

The spectral peak analysis unit includes:

A conjugate unit for conjugate-operating one of the first frequency-domain signal and the second frequency-domain signal,

To output a conjugate value signal;

A multiplication unit for multiplying the other of the first frequency-domain signal and the second frequency-domain signal by the conjugate value signal to output a product signal; and

A spectrum peak value selection unit for selecting a peak value area corresponding to the movement information of the object to be measured according to the product signal to output the calculated value.

5. The moving object detection circuit according to claim 2, further comprising:

A reference signal generating unit for generating the first IF reference signal and the second IF reference signal related to the IF frequency.

6. the moving object detection circuit of claim 5, further comprising:

A digital-to-analog conversion circuit for receiving a third intermediate frequency reference signal and generating a third analog signal accordingly;

A second hybrid circuit for receiving the third analog signal and the high frequency carrier signal and generating a fourth analog signal accordingly; and

A reference signal generating circuit for generating the high frequency carrier signal;

The reference signal generating unit is further configured to generate the third intermediate frequency reference signal related to the intermediate frequency.

7. the moving object detection circuit of claim 2, wherein:

The first hybrid circuit includes:

A first mixer for mixing the high frequency carrier signal and the first analog signal to generate an I-channel analog signal; and

A second mixer for mixing a phase shift signal with the first analog signal to generate a Q-path analog signal;

wherein the second analog signal comprises the I-path analog signal and the Q-path analog signal, and the phase shift signal is generated by shifting a phase of the high-frequency carrier signal;

the analog-digital conversion circuit includes:

a first analog-to-digital converter for receiving the I-path analog signal to generate an I-path digital signal; and

A second analog-to-digital converter for receiving the Q-path analog signal to generate a Q-path digital signal;

Wherein the first digital signal comprises the I-path digital signal, and the second digital signal comprises the Q-path digital signal.

8. The moving object detection circuit of claim 1, wherein the distance detection unit further comprises:

a multiplication unit for multiplying the calculated value and a first adjustment parameter to generate a product of the calculated value and the first adjustment parameter;

A phase capturing unit for capturing a phase value of the product of the calculated value and the first adjusting parameter; and

An amplifying unit for multiplying the phase value by a second adjusting parameter to generate the detection value.

9. the moving object detection circuit of claim 1, wherein:

The first mixing unit includes:

A first multiplying unit for multiplying the first IF reference signal and the intermediate signal to generate the first signal;

and

A second multiplying unit for multiplying the second IF reference signal and the intermediate signal to generate the second signal.

10. The moving object detection circuit of claim 9, wherein:

the time domain to frequency domain analysis unit comprises:

A Fourier transform unit for performing Fourier transform on a time domain signal to generate the at least one frequency domain signal;

Wherein the time domain signal is generated according to the first signal and the second signal.

11. The moving object detection circuit of claim 10, wherein:

The spectral peak analysis unit includes:

A spectrum peak value selection unit for selecting a peak value area corresponding to the tested object according to the at least one frequency domain signal and outputting a positive frequency peak value signal and a negative frequency peak value signal; and

A multiplying unit for multiplying the positive frequency peak signal and the negative frequency peak signal to generate the calculated value.

12. The moving object detection circuit according to claim 9, further comprising:

A reference signal generating unit for generating the first IF reference signal and the second IF reference signal related to the IF frequency.

13. The moving object detection circuit according to claim 12, further comprising:

a digital-to-analog conversion circuit for receiving a third intermediate frequency reference signal and generating a third analog signal accordingly;

A second hybrid circuit for receiving the third analog signal and the high frequency carrier signal and generating a fourth analog signal accordingly; and

A reference signal generating circuit for generating the high frequency carrier signal;

The reference signal generating unit is further configured to generate the third intermediate frequency reference signal related to the intermediate frequency.

14. The moving object detection circuit of claim 9, wherein:

The first hybrid circuit includes:

A first mixer for mixing the high frequency carrier signal and the first analog signal to generate the second analog signal;

And

The analog-digital conversion circuit includes:

the first analog-to-digital converter is used for generating the at least one first digital signal according to the second analog signal.

15. A method for detecting movement information of a measured object, comprising:

mixing an intermediate signal and a first intermediate frequency reference signal, and mixing the intermediate signal and a second intermediate frequency reference signal to generate a first signal and a second signal, respectively;

generating at least one frequency domain signal according to the first signal and the second signal;

Selecting a spectrum peak value according to the at least one frequency domain signal to generate a calculated value; and

Obtaining a detection value according to the calculation value;

The intermediate signal is related to at least one first digital signal, the at least one first digital signal is generated according to a signal reflected by the object to be measured, and the detection value corresponds to the distance of the object to be measured.

16. the method of claim 15, wherein:

Generating the at least one frequency domain signal according to the first signal and the second signal, comprising:

performing Fourier transform on the first signal and the second signal respectively to generate a first frequency-domain signal and a second frequency-domain signal;

wherein the at least one frequency domain signal comprises the first frequency domain signal and the second frequency domain signal;

performing spectral peak selection to generate the calculated value according to the at least one frequency domain signal, comprising:

Performing a conjugate operation on one of the first frequency-domain signal and the second frequency-domain signal to output a conjugate value signal;

multiplying the other of the first frequency-domain signal and the second frequency-domain signal by the conjugate value signal to output a product signal; and

selecting a peak area corresponding to the movement information of the object to be measured according to the product signal to output the calculated value.

17. The method of claim 15, wherein:

Generating the at least one frequency domain signal according to the first signal and the second signal, comprising:

Performing a fourier transform on a time domain signal to generate the at least one frequency domain signal, wherein the time domain signal is generated according to the first signal and the second signal;

Performing spectral peak selection to generate the calculated value according to the at least one frequency domain signal, comprising:

Selecting a peak area corresponding to the tested object according to the at least one frequency domain signal, and outputting a positive frequency peak signal and a negative frequency peak signal; and

Multiplying the positive frequency peak signal and the negative frequency peak signal to generate the calculated value.

Technical Field

The present invention relates to a mobile object detection circuit, and more particularly, to a mobile object distance detection circuit using a double-sideband (double-sideband) Intermediate Frequency (IF) carrier radar.

Background

The detection method is available at present, in which a microwave sensor is used to emit electromagnetic waves, and then the object to be detected is detected according to the electromagnetic waves reflected by the object to be detected. In previous object detection techniques, conventional I/Q signal direct conversion may be used to extract phase information. However, in the signal processing process, the loss of direct current offset (DC offset), flicker noise (flicker noise), leakage from the transmitting end to the receiving end (leakage), and the like is not easily reduced. For this reason, there is still a need in the art for better solutions to ameliorate the disadvantages of the prior art.

Disclosure of Invention

drawings

fig. 1 is a schematic diagram of a moving object detection circuit according to an embodiment of the invention.

FIG. 2 is a schematic diagram of the distance detection unit shown in FIG. 1 according to the present invention.

Fig. 3 is a schematic diagram of a moving object detection circuit according to an embodiment of the invention.

FIG. 4 is a schematic diagram of the peak regions of the frequency spectrums of the first frequency-domain signal and the second frequency-domain signal according to the present invention.

FIG. 5 is a schematic diagram of the distance detecting unit according to the embodiment of FIG. 3.

Fig. 6 is a schematic diagram of a moving object detection circuit according to another embodiment of the invention.

FIG. 7 is a schematic diagram of the peak regions of the spectrum of the positive frequency peak signal and the negative frequency peak signal according to the present invention.

FIG. 8 is a diagram illustrating a distance detection unit according to the embodiment of FIG. 6.

Fig. 9 is a flowchart of a method for detecting movement information of a measured object according to an embodiment of the present invention.

FIG. 10 is a flowchart of the method of generating the frequency domain signal and the calculated value of FIG. 9 according to the present invention.

FIG. 11 is a flowchart illustrating the generation of the frequency domain signal and the calculation of the frequency domain signal in FIG. 9 according to another embodiment of the present invention.

[ description of reference ]

100. 300, 600 moving object detection circuit

obj tested object

A. g hybrid circuit

B analog-digital conversion circuit

C mixing unit

DU distance detection unit

pc high frequency carrier signal

r_a(t), Sa analog signal

S_rx(t) analog received signal

S_tx(t) simulated transmission signal

p1 first IF reference signal

p2 second IF reference signal

p3 third IF reference signal

f_IFIntermediate frequency

Tau radio round trip delay

T (t) radio frequency transmission signal

R (t) radio frequency receiving signal

Sd digital signal

r (n) intermediate signal

u₁(n) first signal

u₂(n) second signal

R_kDetection value

d1 time domain to frequency domain analysis unit

D2 spectrum peak analysis unit

Multiplication units of D3, D22, C61, C62 and D722

A1, A2 and A61 mixer

d4 phase extraction unit

D5 amplifying unit

sf frequency domain signal

calculated value of Vk

pa, pb adjustment parameters

pc' phase shift signal

r_I(t) analog signal of I path

r_Q(t) Q-path analog signal

f_sSampling rate

B1, B2 and B61 analog-to-digital converters

r_I(n) I-path digital signal

r_Q(n) Q-path digital signal

C1, C2 complex multiplication unit

u_p(n) Positive frequency Signal

u_n(n) negative frequency signal

u_I(n) I path signal

u_Q(n) Q path signal

Real number unit of Re

E reference signal generation unit

f digital-to-analog conversion circuit

H phase shift circuit

I reference signal generating circuit

ax, Ar amplifier

ANTx, ANTr antenna device

Fourier transform unit of D11, D12 and D711

U_p(omega) first frequency-domain signal

U_n(omega) second frequency-domain signal

d23 conjugation unit

d21, D721 frequency spectrum peak value selection unit

U_nSignal of conjugated value of (omega)

900 method

910 to 925, 1010 to 1025, 1110 to 1120 steps

The embodiment provides a moving object detection circuit for detecting movement information of a detected object, which comprises a first mixing circuit, an analog-digital conversion circuit, a first mixing unit and a distance detection unit. The first mixing circuit is used for mixing the high-frequency carrier signal and a first analog signal to generate a second analog signal, wherein the first analog signal is generated according to the fact that a transmitting signal is reflected by the tested object. The analog-to-digital conversion circuit is coupled to the first hybrid circuit and used for generating at least one first digital signal according to the second analog signal. The first mixing unit is configured to mix an intermediate signal and first and second intermediate frequency reference signals to generate first and second signals, respectively, wherein the first and second intermediate frequency reference signals are related to an intermediate frequency, and the intermediate signal is related to the at least one first digital signal. The distance detection unit is used for generating a detection value according to the first signal and the second signal, wherein the detection value corresponds to the distance between the detected object and the moving object detection circuit. The distance detection unit comprises a time domain to frequency domain analysis unit and a spectrum peak analysis unit. The time domain to frequency domain analysis unit is used for generating at least one frequency domain signal according to the first signal and the second signal. The spectral peak analysis unit is configured to perform spectral peak selection according to the at least one frequency domain signal to generate a calculated value, wherein the calculated value is related to the detected value.