Frequency conversion frequency modulated continuous wave radar

Abstract

A frequency conversion frequency modulation continuous wave radar converts an oscillation signal outputted from an oscillation unit into a frequency modulation continuous wave signal by a frequency conversion unit, detects objects at different distances, and after a demodulation unit demodulates a detection signal, a calculation unit performs frequency spectrum analysis on the demodulated signal, and judges whether each tone corresponds to a single object or multiple objects based on the relationship between the frequency and phase of each tone in the frequency spectrum, thereby reducing the amount of data required for subsequent analysis.

Description

Technical Field

[0001] This invention relates to a frequency-modulated continuous wave radar, and more particularly to a frequency-converting frequency-modulated continuous wave radar. Background Technology

[0002] Frequency-modulated continuous wave (FMCR) radar transmits a time-varying frequency signal to an object and receives the reflected signal. Since the frequency of the reflected signal also changes over time, the distance between the object and the radar can be calculated simply by determining the frequency difference between the transmitted and reflected signals. However, FMCR radar suffers from insufficient range resolution due to bandwidth limitations. If there is more than one object within the FMCR radar's range resolution, the two objects will appear in the same tone in the demodulated spectrum and become indistinguishable. Previous technologies have used superresolution algorithms, such as multiple signal classification (MUSIC) or the estimation of signal parameters using the rotational invariance technique (ESPRIT), to perform matrix decomposition using the orthogonality of signal and noise spaces, thereby improving spectral resolution. However, due to the high computational complexity of superresolution algorithms and the fact that the improvement is affected by system SNR, the number of targets, and data length, it is difficult to significantly apply them to improving the range resolution of FMCR radar. Summary of the Invention

[0003] The main objective of this invention is to perform spectral analysis on demodulated signals and determine whether a single tone corresponds to a single object or multiple objects based on the relationship between the frequency and phase of the spectral tones. This reduces the amount of data that needs to be processed in subsequent analysis, thereby improving computational efficiency and accuracy, and can also improve the range resolution of frequency-modulated continuous wave radar.

[0004] A frequency-modulated continuous wave radar of the present invention includes an oscillation unit, a frequency conversion unit, an antenna unit, a demodulation unit, and a processing unit. The oscillation unit outputs an oscillation signal. The frequency conversion unit is coupled to the oscillation unit to receive the oscillation signal and converts the oscillation signal into a frequency-modulated continuous wave signal. The antenna unit is coupled to the frequency conversion unit to receive the frequency-modulated continuous wave signal and transmits the frequency-modulated continuous wave signal as a transmit signal to an area. The antenna unit receives the reflected signal from the area as a receive signal. The frequency conversion unit receives the received signal and converts it into a detection signal. The demodulation unit is coupled to the oscillation unit and the frequency conversion unit to receive the oscillation signal and the detection signal. The demodulation unit demodulates the oscillation signal and the detection signal to obtain a demodulated signal. The arithmetic unit is coupled to the demodulation unit to receive the demodulated signal. The arithmetic unit performs spectral analysis on the demodulated signal to obtain the phase and frequency of at least one tone in the frequency domain of the demodulated signal. The arithmetic unit determines whether the tone corresponds to one or more objects based on the phase and frequency of the tone.

[0005] Preferably, the frequency conversion unit has a local oscillator, an up-conversion mixer, and a down-conversion mixer. The local oscillator outputs a local oscillation signal. The up-conversion mixer is electrically connected to the oscillator unit and the local oscillator to receive the oscillation signal and the local oscillation signal. The up-conversion mixer up-converts the oscillation signal into the frequency-modulated continuous wave signal using the local oscillation signal. The down-conversion mixer is electrically connected to the antenna unit and the local oscillator to receive the received signal and the local oscillation signal. The down-conversion mixer down-converts the received signal into the detection signal using the local oscillation signal.

[0006] Preferably, the local oscillator is a voltage-controlled oscillator, and the local oscillator receives and is controlled by a scan signal.

[0007] Preferably, the frequency conversion unit has a power divider electrically connected to the local oscillator to receive the local oscillator signal, and the power divider splits the local oscillator signal into two paths, one of which is transmitted to the up-conversion mixer and the other is transmitted to the down-conversion mixer.

[0008] Preferably, the antenna unit has a transmitting antenna and a receiving antenna. The transmitting antenna is electrically connected to the up-conversion mixer to receive the frequency-modulated continuous wave signal, and the transmitting antenna transmits the frequency-modulated continuous wave signal as the transmitted signal. The receiving antenna is electrically connected to the down-conversion mixer, and the receiving antenna receives the reflected signal as the received signal, and transmits the received signal to the down-conversion mixer.

[0009] Preferably, the demodulation unit has a mixer coupled to the oscillation unit and the down-conversion mixer to receive the oscillation signal and the detection signal, and the mixer is used to mix the oscillation signal and the detection signal to the demodulated signal.

[0010] Preferably, it includes a coupler electrically connected to the oscillation unit to receive the oscillation signal, and the coupler is used to split the oscillation signal into two paths, one of which is transmitted to the up-conversion mixer of the frequency conversion unit, and the other of which is transmitted to the mixer of the demodulation unit.

[0011] Preferably, the processing unit determines whether the tone corresponds to one or more objects by whether the phase and frequency of the tone of the demodulated signal conform to a relational expression, which is:

[0012]

[0013] Where, φ s，i For the i-th tone and its phase, ω s，i ω is the frequency of the i-th tone. B ω is the bandwidth of the continuous wave signal modulated at this frequency. TX Let ω be the frequency of the transmitted signal. TX =ω LO +ω out ω LO Let ω be the frequency of the local oscillation signal. out Let t be the frequency of the oscillation signal. s This is the period of the scan signal.

[0014] Preferably, the processing unit determines whether a tone corresponds to one or more objects based on whether the phase and frequency of the two tones conform to a relational expression, which is:

[0015]

[0016] Where, φ s，ij φ is the phase difference between the i-th and j-th pitches. s，i For the i-th tone and its phase, φ s，j For the phase of the j-th tone, ω s，ij ω is the frequency difference between the i-th and j-th pitches. s，ij =ω s，i -ω s，j ω s，i ω is the frequency of the i-th tone. s，j For the frequency of the j-th tone, t s ω is the period of the scan signal. Bω is the bandwidth of the continuous wave signal modulated at this frequency. TX Let ω be the frequency of the transmitted signal. TX =ω LO +ω out ω LO Let ω be the frequency of the local oscillation signal. out The frequency of the oscillation signal is denoted as .

[0017] Preferably, if the computing unit determines that a single tone corresponds to multiple objects, the computing unit performs a super-resolution algorithm on the frequency range corresponding to the tone to obtain multiple tones in the frequency range, wherein the computing unit uses the frequency of the tone plus or minus a preset value as the frequency range corresponding to the tone.

[0018] This invention utilizes the computing unit to perform spectral analysis on the demodulated signal to obtain the frequency and phase corresponding to each tone in the frequency domain of the demodulated signal. The computing unit can then analyze the relationship between the frequency and phase of each tone to determine whether each tone corresponds to only a single object. This allows for the setting of the frequency range that the super-resolution algorithm needs to process, thereby reducing the amount of data that the subsequent super-resolution algorithm needs to process and significantly improving the range resolution of the frequency-converting frequency-modulated continuous wave radar.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0020] Figure 1 According to an embodiment of the present invention, a functional block diagram of a frequency-converting frequency-modulated continuous wave radar is provided.

[0021] Figure 2 According to an embodiment of the present invention, a circuit diagram of an oscillation unit, a frequency conversion unit, an antenna unit, and a demodulation unit is provided.

[0022] Figure 3 A schematic diagram of the spectrum of the demodulated signal according to an embodiment of the present invention.

[0023] Figure 4 According to an embodiment of the present invention, a schematic diagram of the spectrum of the demodulated signal is shown.

[0024] [Explanation of Key Component Symbols]

[0025] 100: Frequency-converting frequency-modulated continuous wave radar; 110: Oscillator unit

[0026] 120: Frequency conversion unit; 121: Local oscillator source

[0027] 122: Up-frequency mixer 123: Down-frequency mixer

[0028] 124: Power divider; 130: Antenna unit

[0029] 131: Transmitting antenna; 132: Receiving antenna

[0030] 140: Demodulation unit; 150: Processing unit

[0031] 160: Coupler S out Oscillation signal

[0032] S FMCW Frequency-modulated continuous wave signal S scan Scan signal

[0033] S T Transmitted signal A: Area

[0034] S R : Reflected signal S r Received signal

[0035] S demod Demodulated signal tone: pitch

[0036] S d Detection signal S L0 Local oscillation signal Detailed Implementation

[0037] Please see Figure 1 This is a functional block diagram of a frequency-converting frequency-modulated continuous wave radar 100, as an embodiment of the present invention. The frequency-converting frequency-modulated continuous wave radar 100 includes an oscillation unit 110, a frequency conversion unit 120, an antenna unit 130, a demodulation unit 140, and a processing unit 150. The frequency conversion unit 120 is coupled to the oscillation unit 110, the antenna unit 130 is coupled to the frequency conversion unit 120, the demodulation unit 140 is coupled to both the oscillation unit 110 and the frequency conversion unit 120, and the processing unit 150 is coupled to the demodulation unit 140.

[0038] Please see Figure 1 and Figure 2 In this embodiment, the oscillation unit 110 is a voltage-controlled oscillator (VCO), which receives a control voltage (not shown in the figure) and outputs an oscillation signal S. out The oscillation signal S out The oscillation signal S is split into two paths via coupler 160, one of which is the oscillation signal S. out1The other oscillation signal S is transmitted to the frequency conversion unit 120. out2 It is transmitted to the demodulation unit 140.

[0039] Please see Figure 2 The frequency conversion unit 120 is coupled to the oscillation unit 110 via the coupler 160 to receive one of the oscillation signals S. out1 The frequency conversion unit 120 is used to convert the oscillation signal S out1 Converted to frequency-modulated continuous wave signal S FMCW Please see. Figure 2 The frequency conversion unit 120 includes a local oscillator 121, a frequency up mixer 122, a frequency down mixer 123, and a power divider 124. The local oscillator 121 is a voltage-controlled oscillator, and it receives a scanning signal S. scan And under its control, the local oscillation signal S output by the local oscillation source 121 is... L0 The scanning signal S is a frequency-modulated signal whose frequency varies with time. scan The scan signal S is a sawtooth wave, or in other embodiments, the scan signal S scan It can also be other signals whose voltage varies with time. This local oscillation signal S L0 The frequency can be expressed as:

[0040] ω LO (t)=ω LO +2πK v V t (t)

[0041] ω LO (t) represents the local oscillation signal S. L0 Frequency that changes with time, ω LO K is the center frequency of the local oscillator 121. v To adjust the frequency sensitivity of the local oscillator 121, V t (t) represents the scan signal S scan .

[0042] Please see Figure 2 The power divider 124 is electrically connected to the local oscillator 121 to receive the local oscillation signal S. L0 The power divider 124 will convert the local oscillation signal S L0 Divided into two paths, the up-conversion mixer 122 is electrically connected to the coupler 160 and the power divider 124 to receive the oscillation signal S from one of the paths. out1 and the local oscillation signal S L01 The up-conversion mixer 122 will convert the oscillation signal S out1 and the local oscillation signal SL01 Mixing the oscillation signal S out1 Up-frequency conversion is used to generate a frequency-modulated continuous wave signal S. FMCW .

[0043] Please see Figure 1 The antenna element 130 is coupled to the frequency conversion unit 120 to receive the frequency-modulated continuous wave signal S. FMCW The antenna element 130 is used to modulate the continuous wave signal S at this frequency. FMCW The transmission is the transmission signal S T If there is at least one object in region A, then that object will reflect the reflected signal S. R The antenna element 130 receives the reflected signal S reflected from region A. R To receive signal S r Please see. Figure 2 In this embodiment, the antenna unit 130 has a transmitting antenna 131 and a receiving antenna 132. The transmitting antenna 131 is electrically connected to the up-conversion mixer 122 to receive the frequency-modulated continuous wave signal S. FMCW The transmitting antenna 131 modulates the frequency of the continuous wave signal S FMCW The transmission is the transmission signal S. T To region A, the receiving antenna 132 receives the reflected signal S reflected from region A. R For the received signal S r The transmitted signal S T The frequency can be expressed as:

[0044] ω TX (t)=ω out +ω LO (t)

[0045] ω TX (t) represents the transmitted signal S T The frequency, ω out The oscillation signal S out1 The frequency.

[0046] Please see Figure 2 The down-conversion mixer 123 is electrically connected to the receiving antenna 132 and the power divider 124 to receive the received signal S. r And the other local oscillation signal S L02 The down-conversion mixer 123 will receive the signal S r and the local oscillation signal S L02 Mixing the received signal S r Frequency reduction to detection signal S d .

[0047] Please see Figure 1The demodulation unit 140 is coupled to the oscillation unit 110 and the frequency conversion unit 120 to receive the oscillation signal S. out and the detection signal S d The demodulation unit 140 is used to detect the signal S. d The demodulated signal S is obtained by demodulation. demod Please see. Figure 2 In this embodiment, the demodulation unit 140 is used to demodulate the oscillation signal S. out2 and the detection signal S d Phase demodulation is performed, wherein the demodulation unit 140 has a mixer that is coupled to the coupler 160 and the down-conversion mixer 123 to receive the oscillation signal S. out2 and the detection signal S d The mixer is used to convert the oscillation signal S out2 and the detection signal S d The mixing is the demodulated signal S demod The demodulated signal S demod It can be represented as:

[0048]

[0049] or

[0050]

[0051] S I (t) is the in-phase fundamental frequency signal, S Q (t) is the orthogonal fundamental frequency signal, E I，i E Q，i For the demodulated signal S demod The amplitude, α i (t) represents the phase change caused by the internal circuitry of the frequency-modulated continuous wave radar 100 and the i-th object, while the demodulated signal S demod Represented as S I (t) or S Q (t) then depends on the demodulated signal S output by the mixer. demod The phase determines it.

[0052] The phase change caused by the internal circuitry of the frequency-conversion frequency-modulated continuous wave radar 100 and the i-th object can be expressed as follows:

[0053] α i (t)≈(ω out +ω LO +2πK v V t (t))×τ s，i (t)

[0054] τ s，i(t) represents the time delay caused by the internal circuitry of the frequency-modulated continuous wave radar 100 and the i-th object, which can be expressed as:

[0055]

[0056] τ int，1 τ is the delay between the up-conversion mixer 122 and the transmitting antenna 131. int，2 τ is the delay between the receiving antenna 132 and the down-conversion mixer 123. p，i (t) represents the transmitted signal S T The transmitted signal S is transmitted to the i-th object by the transmitting antenna 131 and the reflected signal S. R The delay R between the i-th object and the receiving antenna 132 i x is the distance between the i-th object and the antenna element 130. i (t) represents the displacement of the i-th object, and C represents the speed of light.

[0057] Please refer to the following: Figure 1 The arithmetic unit 150 is coupled to the demodulation unit 140 to receive the demodulated signal S. demod The processing unit 150 is used to process the demodulated signal S demod Perform spectral analysis to obtain the frequency domain of the demodulated signal S. demod Phase and frequency of at least one tone. Please refer to [link / reference]. Figure 3 , is the demodulated signal S demod A schematic diagram of the spectrum obtained through spectral analysis, containing three tones. In the diagram, ω1, ω2, and ω3 represent the frequencies of these three tones, and M1∠φ1, M2∠φ2, and M3∠φ3 represent the amplitude and phase of the three tones, respectively. This spectrum can be represented as:

[0058]

[0059] or

[0060]

[0061] w(t) and W(ω) are the Fourier transform pairs of the window function, ω s，i For the i-th tone, φ is the frequency of that tone. s，i This refers to the phase of the i-th tone.

[0062] Since each tone corresponds to a specific object in region A transmitting a signal S... T The resulting phase change, therefore, Figure 3The three tones of this spectrum can indicate that there are at least three objects in region A, but due to distance resolution issues, it is not possible to confirm whether each tone corresponds to a single object or multiple objects.

[0063] In this embodiment, after obtaining the phase and frequency of each tone, the processing unit 150 determines whether the tone corresponds to one or more objects based on the phase and frequency of the tone. In one embodiment, the processing unit 150 uses the demodulated signal S in the frequency domain... demod To determine whether a tone corresponds to one or more objects, we need to check if its phase and frequency conform to a certain relationship. This relationship is:

[0064]

[0065] Where, φ s，i For the i-th tone, ω is the phase of that tone. s，i ω represents the frequency of the i-th tone. B The continuous wave signal S is modulated at this frequency. FMCW bandwidth, t s For the scan signal S scan The cycle.

[0066] If the equation holds true, it means that the tone corresponds to only one object; if the equation does not hold true, it means that the tone corresponds to multiple objects. Therefore, the operation unit 150 performs a super-resolution algorithm on the frequency range corresponding to the tone to obtain multiple tone ranges within that frequency range. In this embodiment, the operation unit 150 uses the frequency of the tone plus or minus a preset value as the frequency range corresponding to the tone. For example, if the frequency and phase of a tone with a frequency of 327Hz in the spectrum do not conform to the above equation, the operation unit 150 uses 327Hz plus or minus a preset value of 100Hz as the frequency range corresponding to the tone, that is, it uses 227Hz to 427Hz as the frequency range of the tone and performs a super-resolution algorithm on this frequency range to significantly improve the resolution of the Fourier transform spectrum. Please refer to [link to relevant documentation]. Figure 4 The spectrum obtained by performing a super-resolution algorithm on the frequency range can be used to obtain two more tones in the frequency range, thus determining that there are four objects in region A.

[0067] Preferably, after the arithmetic unit 150 records the changes in the phase position of the same frequency position in different frequency sweep intervals, it can calculate the displacement of the object at that frequency position. If the displacement of the object is caused by the physiological symptoms of the object, the calculated displacement of the object can be represented as the physiological signal of the object.

[0068] In another embodiment, considering the leakage between the transmitting antenna 131 and the receiving antenna 132, even if there is only a single object in region A, two tones may appear in the spectrum. Therefore, it can be determined whether the tone corresponds to one or more objects by whether the phase and frequency of the two tones conform to the following relationship:

[0069]

[0070] Where, φ s，ij φ is the phase difference between the i-th and j-th pitches. s，i For the i-th tone and its phase, φ s，j For the phase of the j-th tone, ω s，ij ω is the frequency difference between the i-th and j-th pitches. s，ij =ω s，i -ω s，j ω s，i ω is the frequency of the i-th tone. s，j For the frequency of the j-th tone, t s For the scan signal S scan The period, ω B The continuous wave signal S is modulated at this frequency. FMCW The bandwidth.

[0071] Similarly, if the equation of the relation is true, it means that the tone corresponds to only one object, and if the equation of the relation is not true, it means that the tone corresponds to multiple objects. Therefore, the operation unit 150 performs a super-resolution algorithm on the frequency range corresponding to the tone to obtain multiple tones in the frequency range and determine the number of objects in the region A.

[0072] The present invention utilizes the processing unit 150 to demodulate the signal S demod Perform spectral analysis to obtain the demodulated signal S in the frequency domain. demod By analyzing the frequency and phase of each tone, the computing unit 150 can determine whether each tone corresponds to a single object. This allows the super-resolution algorithm to set the frequency range to be processed, thereby reducing the amount of data that the super-resolution algorithm needs to process and significantly improving the computational efficiency and accuracy. It can also improve the range resolution of the frequency-modulated continuous wave radar 100.

[0073] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A frequency conversion frequency modulation continuous wave radar, comprising: an oscillation unit, outputting an oscillation signal; a frequency conversion unit, coupled to the oscillation unit to receive the oscillation signal, the frequency conversion unit being configured to convert the oscillation signal into a frequency modulation continuous wave signal, the frequency conversion unit having a local oscillator, the local oscillator outputting a local oscillation signal, the local oscillator receiving a scanning signal and being controlled thereby; an antenna unit, coupled to the frequency conversion unit to receive the frequency modulation continuous wave signal, the antenna unit being configured to transmit the frequency modulation continuous wave signal as a transmitted signal to a region, the antenna unit receiving a reflected signal reflected by the region as a received signal, the frequency conversion unit receiving the received signal and converting the received signal into a detection signal; a demodulation unit, coupled to the oscillation unit and the frequency conversion unit to receive the oscillation signal and the detection signal, the demodulation unit being configured to demodulate the oscillation signal and the detection signal to obtain a demodulation signal; an operation unit, coupled to the demodulation unit to receive the demodulation signal, the operation unit being configured to perform a frequency spectrum analysis on the demodulation signal to obtain a phase and a frequency of at least one tone in the frequency domain of the demodulation signal, and the operation unit being configured to determine whether the tone corresponds to one object or multiple objects according to the phase and the frequency of the tone; wherein the operation unit is configured to determine whether the tone corresponds to one object or multiple objects according to whether the phase and the frequency of the tone of the demodulation signal satisfy a relationship, the relationship being: the frequency conversion unit further having an up-conversion mixer and a down-conversion mixer, the up-conversion mixer being electrically connected to the oscillation unit and the local oscillator to receive the oscillation signal and the local oscillation signal, the up-conversion mixer being configured to up-convert the oscillation signal into the frequency modulation continuous wave signal by using the local oscillation signal, the down-conversion mixer being electrically connected to the antenna unit and the local oscillator to receive the received signal and the local oscillation signal, the down-conversion mixer being configured to down-convert the received signal into the detection signal by using the local oscillation signal. wherein, is the phase of the mth tone, i is the phase of the mth tone, is the frequency of the mth tone, i is the frequency of the mth tone, is the bandwidth of the frequency modulated continuous wave signal, is the frequency of the transmitted signal, , is the frequency of the local oscillator signal, is the frequency of the local oscillator signal, is the period of the sweep signal.

2. The frequency conversion frequency modulated continuous wave radar according to claim 1, characterized in that the local oscillator is a voltage controlled oscillator.

3. The frequency conversion frequency modulated continuous wave radar of claim 2, wherein, the frequency conversion unit has a power divider, the power divider being electrically connected to the local oscillator to receive the local oscillation signal, and the power divider being configured to divide the local oscillation signal into two paths, one of which is transmitted to the up-conversion mixer and the other of which is transmitted to the down-conversion mixer.

4. The frequency conversion frequency modulated continuous wave radar of claim 2, wherein, the antenna unit has a transmitting antenna and a receiving antenna, the transmitting antenna being electrically connected to the up-conversion mixer to receive the frequency modulation continuous wave signal, and the transmitting antenna being configured to transmit the frequency modulation continuous wave signal as the transmitted signal, the receiving antenna being electrically connected to the down-conversion mixer, the receiving antenna being configured to receive the reflected signal as the received signal and transmit the received signal to the down-conversion mixer.

5. The frequency converted frequency modulated continuous wave radar of claim 2, wherein, the demodulation unit has a mixer, the mixer being coupled to the oscillation unit and the down-conversion mixer to receive the oscillation signal and the detection signal, the mixer being configured to mix the oscillation signal and the detection signal to obtain the demodulation signal.

6. The frequency converted frequency modulated continuous wave radar according to claim 2, characterized in that ​ 7. The frequency converted frequency modulated continuous wave radar according to claim 6, characterized in that The coupling device is electrically connected to the oscillation unit to receive the oscillation signal, and the coupling device is used to divide the oscillation signal into two paths, one of which is transmitted to the up-conversion mixer of the frequency conversion unit, and the other is transmitted to the mixer of the demodulation unit.

8. The frequency converted frequency modulated continuous wave radar of claim 3, wherein, The operation unit determines whether the tones corresponding to one object or multiple objects according to whether the phases and the frequencies of the two tones satisfy a relationship, and the relationship is: wherein, is a phase difference between the first tone and the second tone, i j is the phase of the first tone, i is the phase of the first tone, j is a frequency difference between the first tone and the second tone, i j , is the frequency of the first tone, i is the frequency of the first tone, j is a period of the scan signal, is a bandwidth of the frequency modulated continuous wave signal, is a frequency of the transmit signal, , is a frequency of the local oscillation signal, is a frequency of the oscillation signal.​​​​​​​​ 9. The frequency converted frequency modulated continuous wave radar of claim 1, wherein, If the operation unit determines that a single tone corresponds to multiple objects, the operation unit performs a super-resolution algorithm on a frequency interval corresponding to the tone to obtain multiple tones in the frequency interval, and the operation unit adds and subtracts a preset value from the frequency of the tone as the frequency interval corresponding to the tone.

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