Frequency modulation continuous wave radar and detection method thereof

Abstract

The invention discloses a frequency-modulated continuous wave radar and a detection method thereof. The frequency modulated continuous wave radar is used for detecting an object with a sensor and comprises a chirp signal generator, a transmitting module, a receiving module, a processing module and an operation module. The chirp signal generator can generate a radar signal. The transmitting module may transmit a radar signal to an object. The receiving module can receive a reflected signal from the object, wherein the reflected signal comprises a characteristic signal and a sensing signal. The processing module can generate an integrated digital signal according to the reflected signal and the radar signal. The operation module can analyze the integrated digital signal to obtain first digital information and second digital information, the first digital information can correspond to the characteristic signal, and the second digital information can correspond to the sensing signal.

Description

Technical Field

[0001] The present invention relates to a frequency modulated continuous wave (FMCW) radar, and in particular to a frequency modulated continuous wave radar and a detection method thereof. Background Art

[0002] In recent years, physiological signal (vital sign) detection technology has flourished (for example: body temperature measurement, blood oxygen concentration detection, and non-contact heartbeat and respiratory rate radar detection devices). These have gradually been applied to patient care, elderly care, and infant care. In addition to these physiological signals, temperature measurement is also an important care item for patients, the elderly, and infants who need to measure their body temperature. In today's lack of care manpower, whether it is possible to provide detection equipment to assist these care is an urgent need. Summary of the invention

[0003] In a preferred embodiment, the present invention proposes a frequency modulated continuous wave radar for detecting an object with a sensor. The frequency modulated continuous wave radar includes a chirp signal generator, a transmitting module, a receiving module, a processing module, and a computing module. The chirp signal generator generates a radar signal. The transmitting module transmits the radar signal to the object. The receiving module receives a reflected signal from the object, wherein the reflected signal includes a characteristic signal and a sensing signal. The processing module generates an integrated digital signal based on the reflected signal and the radar signal. The computing module analyzes the integrated digital signal to obtain a first digital information and a second digital information, wherein the first digital information corresponds to the characteristic signal, and the second digital information corresponds to the sensing signal.

[0004] In a preferred embodiment, the present invention proposes a detection method of a frequency modulated continuous wave radar, comprising the following steps: generating a radar signal by a chirp signal generator; transmitting the radar signal to an object, wherein the object has a sensor; receiving a reflection signal from the object, wherein the reflection signal includes a characteristic signal and a sensing signal; generating an integrated digital signal based on the reflection signal and the radar signal; and analyzing the integrated digital signal to obtain a first digital information and a second digital information, wherein the first digital information corresponds to the characteristic signal, and the second digital information corresponds to the sensing signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 is a schematic diagram showing a FMCW radar according to an embodiment of the present invention.

[0006] Figure 2 FIG. 4 is a schematic diagram showing a sensor according to an embodiment of the present invention.

[0007] Figure 3A is a schematic diagram showing a FMCW radar according to an embodiment of the present invention.

[0008] Figure 3B is a schematic diagram showing a computing module according to an embodiment of the present invention.

[0009] Figure 4 is a waveform diagram showing an integrated digital signal according to an embodiment of the present invention.

[0010] Figure 5A is a diagram showing frequency variation of a radar signal according to an embodiment of the present invention.

[0011] Figure 5B is a diagram showing frequency variation of a radar signal according to an embodiment of the present invention.

[0012] Figure 5C FIG. 4 is a frequency domain diagram showing the integrated digital signal after the range fast Fourier transform process is performed according to an embodiment of the present invention.

[0013] Figure 5D FIG. 4 is a time domain diagram showing an integrated digital signal according to an embodiment of the present invention.

[0014] Figure 6 is a schematic diagram showing a time axis according to an embodiment of the present invention.

[0015] Figure 7 is a schematic diagram showing a time axis according to an embodiment of the present invention.

[0016] Figure 8 is a flow chart showing a detection method of a FMCW radar according to an embodiment of the present invention.

[0017] The reference numerals are described as follows:

[0018] 100, 300: Frequency Modulated Continuous Wave Radar

[0019] 110, 310: Chirp signal generator

[0020] 120, 320: Transmitter module

[0021] 130, 330: receiving module

[0022] 140, 340: Processing module

[0023] 150, 350, 450: computing module

[0024] 160: Object

[0025] 170: Sensor

[0026] 172: Antenna module

[0027] 174: Interdigital transducer

[0028] 176: Piezoelectric substrate

[0029] 178: Reflector

[0030] 322: Transmitting antenna

[0031] 324: Power Amplifier

[0032] 332: Receiving antenna

[0033] 334: Receiving Circuit

[0034] 346: FM Continuous Wave Demodulator

[0035] 348: Analog to Digital Converter

[0036] 354: Timing Unit

[0037] 355: Frequency selection unit

[0038] 356: Segmentation Unit

[0039] 457: Fourier Transform Unit

[0040] 458: Analysis Unit

[0041] BW: Operation bandwidth

[0042] FA: Initial frequency

[0043] FB: Final frequency

[0044] FS: Separation frequency point

[0045] S1: First electrical signal

[0046] S2: First surface acoustic wave signal

[0047] S3: Second surface acoustic wave signal

[0048] S4: Second electrical signal

[0049] S810, S820, S830, S840, S850: Steps

[0050] SD1: First Digital Information

[0051] SD2: Second digital information

[0052] SE: characteristic signal

[0053] SF: Radar signal

[0054] SI: Integrated Digital Signal

[0055] SL: rising slope

[0056] SM: intermediate frequency signal

[0057] SR: reflected signal

[0058] SS: Sensing signal

[0059] SQ: Conversion results

[0060] T1: First interval

[0061] T2: The second interval

[0062] TC: Cycle Time

[0063] TD1: First delay time

[0064] TD2: Second delay time

[0065] TD3: Third delay time

[0066] TS: Separation time point

[0067] ΔF1: First frequency difference

[0068] ΔF2: Second frequency difference

[0069] ΔF3: The third frequency difference DETAILED DESCRIPTION

[0070] In order to make the purpose, features and advantages of the present invention more clearly understood, specific embodiments of the present invention are given below and described in detail with reference to the accompanying drawings.

[0071] Certain words are used in the specification and claims to refer to specific components. It should be understood by those skilled in the art that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. The words "including" and "comprising" mentioned throughout the specification and claims are open-ended terms and should be interpreted as "including but not limited to". The word "substantially" means that within an acceptable error range, those skilled in the art can solve the technical problem and achieve the basic technical effect within a certain error range. In addition, the word "coupled" in this specification includes any direct and indirect electrical connection means. Therefore, if the text describes a first device coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device via other devices or connection means.

[0072] The following disclosure provides many different embodiments or examples to implement the different features of the present invention. The following disclosure describes specific examples of various components and their arrangements to simplify the description. Of course, these specific examples are not intended to be limiting. For example, if the present disclosure describes a first feature formed on or above a second feature, it means that it may include an embodiment in which the first feature and the second feature are in direct contact, and may also include an embodiment in which an additional feature is formed between the first feature and the second feature, so that the first feature and the second feature may not be in direct contact. In addition, different examples in the following disclosure may reuse the same reference symbols or (and) marks. These repetitions are for the purpose of simplification and clarity, and are not intended to limit the specific relationship between the different embodiments or (and) structures discussed.

[0073] Figure 1 FIG. 1 is a schematic diagram showing a frequency modulated continuous wave (FMCW) radar 100 according to an embodiment of the present invention. Figure 1 In the embodiment of FIG. 1 , the FMCW radar 100 includes: a chirp signal generator 110, a transmitter module 120, a receiver module 130, a processing module 140, and a computing module 150. It should be understood that although not shown in FIG. Figure 1 However, the FMCW radar 100 may further include other components, such as: a housing, a controller, or (and) a power supply module.

[0074] In some embodiments, the FMCW radar 100 can be used to detect an object 160 having a sensor 170. It should be noted that the object 160 and its sensor 170 are both external components and are not part of the FMCW radar 100. For example, the object 160 may be a human body, and the sensor 170 may be disposed at any location on the human body, but is not limited thereto.

[0075] The chirp signal generator 110 may be used to generate a radar signal SF. In some embodiments, the radar signal SF has a linear modulation frequency. For example, the linear modulation frequency of the radar signal SF may be between 24 GHz and 26 GHz, or between 77 GHz and 81 GHz, but is not limited thereto.

[0076] The transmitting module 120 is coupled to the chirp signal generator 110. The transmitting module 120 can transmit the aforementioned radar signal SF to the object 160. In response, the receiving module 130 can receive a reflection signal SR from the object 160, wherein the reflection signal SR includes a characteristic signal SE and a sensing signal SS. In detail, the characteristic signal SE may include information about the object 160 itself, and the sensing signal SS may include information about the sensor 170. For example, when the object 160 receives the aforementioned radar signal SF, it may return the corresponding characteristic signal SE. In some embodiments, the characteristic signal SE may also be a physiological signal (VitalSign) or physiological information.

[0077] The processing module 140 is coupled to the chirp signal generator 110 and the receiving module 130, wherein the processing module 140 can generate an integrated digital signal SI according to the reflected signal SR and the radar signal SF. The operation module 150 is coupled to the processing module 140, wherein the operation module 150 can analyze the integrated digital signal SI to obtain a first digital information SD1 and a second digital information SD2. It should be noted that the first digital information SD1 corresponds to the characteristic signal SE, and the second digital information SD2 corresponds to the sensing signal SS.

[0078] Specifically, the operation module 150 may execute a first signal processing procedure for the integrated digital signal SI to obtain the first digital information SD1. In some embodiments, the first signal processing procedure includes various algorithms, such as time domain processing, frequency domain processing, or artificial intelligence machine learning. The first digital information SD1 extracted from the integrated digital signal SI may include breathing or (and) heartbeat information, but is not limited thereto.

[0079] In some embodiments, the aforementioned artificial intelligence machine learning algorithm may include: supervised learning, unsupervised learning, semi-supervised learning, or reinforcement learning.

[0080] In addition, the operation module 150 can further perform a second signal processing procedure on the integrated digital signal SI to obtain the second digital information SD2. In some embodiments, the second signal processing procedure includes various algorithms, such as time domain processing or artificial intelligence machine learning. The second digital information SD2 extracted from the integrated digital signal SI may include information on temperature, humidity, pressure, or (and) chemical composition, but is not limited thereto.

[0081] Generally speaking, the use of the chirp signal generator 110 helps to improve the detection accuracy of the FMCW radar 100. In addition, the FMCW radar 100 only needs to use the same transmitting module 120 and receiving module 130 to obtain two different information at the same time, so it can effectively simplify the overall circuit complexity and reduce the relevant manufacturing cost. Under the design of the present invention, the operation module 150 of the FMCW radar 100 can further separate the two different information from each other to facilitate subsequent analysis and processing.

[0082] Figure 2 FIG. 1 is a schematic diagram showing a sensor 170 according to an embodiment of the present invention. Figure 2 In the embodiment of the present invention, the sensor 170 is a passive surface acoustic wave (SAW) sensor, and includes an antenna module 172, an interdigital transducer (IDT) 174, a piezoelectric substrate 176, and one or more reflectors 178. For example, when the sensor 170 receives the aforementioned radar signal SF, it can return a corresponding sensing signal SS.

[0083] First, the antenna module 172 can receive the radar signal SF, and can generate a first electric signal S1 according to the radar signal SF. The interdigitated transducer 174 is coupled to the antenna module 172, and can be disposed on the piezoelectric substrate 176. Due to the reverse piezoelectric effect of the piezoelectric substrate 176, the interdigitated transducer 174 can convert the first electric signal S1 into a first surface acoustic wave signal S2. Then, the aforementioned reflector 178 can be used to reflect the first surface acoustic wave signal S2, thereby generating a second surface acoustic wave signal S3, wherein the propagation directions of the second surface acoustic wave signal S3 and the first surface acoustic wave signal S2 are exactly opposite. Due to the piezoelectric effect of the piezoelectric substrate 176, the interdigitated transducer 174 can further convert the second surface acoustic wave signal S3 into a second electric signal S4. Finally, the antenna module 172 may receive the second electrical signal S4 , and may generate and transmit the aforementioned sensing signal SS to the FMCW radar 100 according to the second electrical signal S4 .

[0084] It should be noted that the propagation speed of the radar signal SF and the reflected signal SR is almost equal to the speed of light. However, the propagation speed of the first surface acoustic wave signal S2 and the second surface acoustic wave signal S3 is only roughly equivalent to the general sound speed, and it will also be affected by the ambient temperature, which causes a longer delay time (DelayTime) between the sensing signal SS and the radar signal SF. In addition, because the characteristic signal SE has no correlation with the surface acoustic wave signal, the receiving time point of the characteristic signal SE is usually earlier than the receiving time point of the sensing signal SS. In some embodiments, by analyzing the delay time of the sensing signal SS, the operation unit 150 of the FMCW radar 100 can also estimate the possible temperature of the sensor 170, which can also be roughly equivalent to the current temperature of the object 160. In some embodiments, if the sensor 170 includes more reflectors 178, it will provide multiple delay times, thereby improving the accuracy of the aforementioned temperature estimation.

[0085] The following embodiments will introduce various configurations and detailed structural features of the FMCW radar 100. It should be understood that these drawings and descriptions are only for illustrative purposes and are not intended to limit the present invention.

[0086] Figure 3A is a schematic diagram showing a FMCW radar 300 according to an embodiment of the present invention. Figure 3A and Figure 1 Similar. Figure 3A In the embodiment of the present invention, the FMCW radar 300 includes a chirp signal generator 310 , a transmitting module 320 , a receiving module 330 , a processing module 340 , and a computing module 350 .

[0087] The chirp signal generator 310 may be used to generate a radar signal SF. The transmitting module 320 includes a transmitting antenna 322 and a power amplifier 324, wherein the transmitting antenna 322 is coupled to the chirp signal generator 310 via the power amplifier 324. In detail, the power amplifier 324 may be used to amplify the radar signal SF, and the transmitting antenna 322 may be used to transmit the amplified radar signal SF. The receiving module 330 includes a receiving antenna 332 and a receiving circuit 334. The receiving circuit 334 is coupled to the receiving antenna 332. The receiving antenna 332 may be used to receive a reflected signal SR, wherein the reflected signal SR includes a characteristic signal SE and a sensing signal SS. For example, the receiving circuit 334 may include a low noise amplifier (LNA) and a filter circuit, but is not limited thereto.

[0088] As mentioned above, there is usually a long delay time between the sensing signal SS and the radar signal SF. Therefore, in some embodiments, the receiving antenna 332 of the receiving module 330 will receive the sensing signal SS only after the receiving antenna 332 of the receiving module 330 has received the characteristic signal SE.

[0089] The shapes and types of the transmitting antenna 322 and the receiving antenna 332 are not particularly limited in the present invention. In some embodiments, either the transmitting antenna 322 or the receiving antenna 332 may be a patch antenna, a monopole antenna, a dipole antenna, a loop antenna, a planar inverted F antenna (PIFA), or a chip antenna.

[0090] The processing module 340 includes a frequency modulated continuous wave demodulator (FMCW Demodulator) 346 and an analog-to-digital converter (ADC) 348. The FMCW demodulator 346 is coupled to the chirp signal generator 310 and the receiving circuit 334 to simultaneously obtain the radar signal SF and the reflected signal SR. For example, the FMCW demodulator 346 may include a mixer and a band-pass filter (BPF), but is not limited thereto. Then, the FMCW demodulator 346 may generate an intermediate frequency (IF) signal SM according to the reflected signal SR and the radar signal SF. In some embodiments, the intermediate frequency signal SM includes a first frequency difference (Frequency Difference) ΔF1 between the characteristic signal SE and the radar signal SF, and a second frequency difference ΔF2 between the sensing signal SS and the radar signal SF. The analog-to-digital converter 348 is coupled to the FMCW demodulator 346. The analog-to-digital converter 348 can convert the intermediate frequency signal SM into an integrated digital signal SI. In some embodiments, the FMCW demodulator 346 and the analog-to-digital converter 348 can also be integrated into a single circuit.

[0091] The operation module 350 is coupled to the processing module 340, wherein the integrated digital signal SI received by the operation module 350 may include a first digital information SD1 and a second digital information SD2. In some embodiments, the operation module 350 may include a timing unit 354, a frequency selection unit 355, and a segmentation unit 356, and its functions will be described in detail in the following embodiments. It must be understood that the aforementioned timing unit 354, frequency selection unit 355, and segmentation unit 356 can be implemented by means of hardware circuits or software programs. In addition, in some embodiments, the operation module 350 may also only include either the timing unit 354 or the frequency selection unit 355.

[0092] Figure 3B FIG. 4 is a schematic diagram showing a computing module 450 according to an embodiment of the present invention. Figure 3BIn the embodiment of the present invention, the operation module 450 includes a Fourier transform unit 457 and an analysis unit 458. For example, the aforementioned integrated digital signal SI may include a data matrix, and the Fourier transform unit 457 may be used to perform a Fast Fourier Transform (FFT) function. First, the Fourier transform unit 457 may perform a Range-FFT program and a Doppler-FFT program on the data matrix of the integrated digital signal SI to generate a transformation result SQ. Then, the analysis unit 458 may further analyze the transformation result SQ of the Fourier transform unit 457 to obtain the aforementioned first digital information SD1 and second digital information SD2.

[0093] Figure 4 is a waveform diagram showing an integrated digital signal SI according to an embodiment of the present invention, wherein the horizontal axis represents time (μs) and the vertical axis represents signal amplitude (mV). As mentioned above, the first digital information SD1 corresponds to the characteristic signal SE, and the second digital information SD2 corresponds to the sensing signal SS. Figure 4 In the embodiment, since the receiving time point of the sensing signal SS is usually later than the receiving time point of the characteristic signal SE, the operation module 350 can determine the integrated digital signal SI as the first digital information SD1 and the second digital information SD2 according to a separation time point TS.

[0094] In detail, the first digital information SD1 may appear before the separation time point TS, and the second digital information SD2 may appear after the separation time point TS. First, the timing unit 354 of the operation module 350 can calculate the precise separation time point TS. Then, the segmentation unit 356 of the operation module 350 uses the separation time point TS to determine the integrated digital signal SI into two parts, the former of which can be regarded as the first digital information SD1 and the latter of which can be regarded as the second digital information SD2. In some embodiments, the separation time point TS may be located about 0.5μs or 1μs after the transmitting module 320 transmits the radar signal SF. For example, if the transmitting module 320 happens to transmit the radar signal SF at 0μs, the separation time point TS can be set at 0.5μs or 1μs. The possible range of the above separation time point TS is obtained based on multiple experimental results, which helps to improve the signal judgment accuracy of the operation module 350 of the FMCW radar 300.

[0095] Figure 5A is a frequency variation diagram of a radar signal SF according to an embodiment of the present invention, wherein the horizontal axis represents time (μs) and the vertical axis represents signal frequency (GHz). Figure 5AIn the embodiment of the present invention, the radar signal SF has a linear modulation frequency. First, the frequency of the radar signal SF is an initial frequency FA. Then, after a period of time TC has passed, the frequency of the radar signal SF will rise to a final frequency FB. For example, the initial frequency FA may be 24 GHz or 77 GHz, the final frequency FB may be 26 GHz or 81 GHz, and the period of time TC may be 40 μs, but is not limited thereto. In detail, the relevant parameters of the radar signal SF may be as described in the following equations (1) and (2):

[0096] BW=FB-FA (1)

[0097]

[0098] Wherein “BW” represents an operating bandwidth BW of the radar signal SF, “SL” represents a rising slope SL of the radar signal SF, “FA” represents an initial frequency FA of the radar signal SF, “FB” represents a final frequency FB of the radar signal SF, and “TC” represents a cycle time TC of the radar signal SF.

[0099] According to equation (1), by subtracting the initial frequency FA from the final frequency FB, the operating bandwidth BW of the radar signal SF can be calculated. In addition, according to equation (2), by dividing the operating bandwidth BW by the cycle time TC, the rising slope SL of the radar signal SF can be calculated.

[0100] For example, if the transmitting module 320 happens to transmit the radar signal SF at 0 μs, the receiving module 330 may start to receive the characteristic signal SE after a first delay time TD1, and the receiving module 330 may start to receive the sensing signal SS after a second delay time TD2. Compared with the characteristic signal SE still having the initial frequency FA, ​​the frequency of the corresponding radar signal SF at this time may be equal to the initial frequency FA plus a first frequency difference ΔF1. In addition, compared with the sensing signal SS still having the initial frequency FA, ​​the frequency of the corresponding radar signal SF at this time may be equal to the initial frequency FA plus a second frequency difference ΔF2. In detail, the first delay time TD1 and the second delay time TD2 can be calculated according to the following equations (3) and (4):

[0101]

[0102]

[0103] Wherein “TD1” represents the first delay time TD1, “TD2” represents the second delay time TD2, “ΔF1” represents the first frequency difference ΔF1, “ΔF2” represents the second frequency difference ΔF2, and “SL” represents the rising slope SL of the radar signal SF.

[0104] According to equations (3) and (4), if the rising slope SL of the radar signal SF is known, the first delay time TD1 of the characteristic signal SE and the second delay time TD2 of the sensing signal SS can be directly determined by analyzing the first frequency difference ΔF1 and the second frequency difference ΔF2. In some embodiments, the aforementioned separation time point TS can be between the first delay time TD1 and the second delay time TD2. In addition, at the separation time point TS, the corresponding frequency of the radar signal SF can be regarded as a separation frequency point FS. It should be noted that in order to make it easier for readers to understand the relative relationship of the aforementioned parameters of the present invention, Figure 5A In some embodiments, if multiple radar signals SF are used simultaneously, the operation module 450 can also calculate the speed or phase change of the object 160 by Doppler fast Fourier transform.

[0105] In some embodiments, the operation module 350 can also determine the integrated digital signal SI as the first digital information SD1 and the second digital information SD2 according to the separation frequency point FS. In detail, the frequency of the characteristic signal SE can be lower than the separation frequency point FS, and the frequency of the sensing signal SS can be higher than the separation frequency point FS. First, the frequency selection unit 355 of the operation module 350 can provide an accurate separation frequency point FS. Then, the segmentation unit 356 of the operation module 350 uses this separation frequency point FS to determine the integrated digital signal SI into two parts, a low part and a high part, wherein the low part can be regarded as the first digital information SD1, and the high part can be regarded as the second digital information SD2. In some embodiments, the separation frequency point FS can be approximately equal to 25MHz or 50MHz, which can correspond to 0.5μs or 1μs of the separation time point TS, respectively. The possible range of the above separation frequency point FS is obtained based on multiple experimental results, which helps to improve the signal judgment accuracy of the operation module 350 of the FMCW radar 300.

[0106] Figure 5B is a diagram showing the frequency variation of the radar signal SF according to an embodiment of the present invention. Figure 5B In the embodiment, a plurality of reflected signals SR are received at the first delay time TD1, the second delay time TD2, and the third delay time TD3, respectively. A first frequency difference ΔF1, a second frequency difference ΔF2, and a third frequency difference ΔF3 may be formed between the corresponding radar signal SF and the aforementioned reflected signal SR, respectively. The information of the above frequency differences may all be included in the aforementioned intermediate frequency signal SM.

[0107] Figure 5C is a frequency domain diagram showing the integrated digital signal SI according to an embodiment of the present invention after the range fast Fourier transform process is performed. Figure 5CAccording to the measurement result, the first frequency difference ΔF1, the second frequency difference ΔF2, and the third frequency difference ΔF3 will have a larger signal strength. By selecting a separation frequency point FS, a portion of the integrated digital signal SI below the separation frequency point FS may include information corresponding to the characteristic signal SE, and another portion of the integrated digital signal SI above the separation frequency point FS may include information corresponding to the sensing signal SS, but the present invention is not limited thereto.

[0108] FIG. D is a time domain diagram of the integrated digital signal SI according to an embodiment of the present invention. According to equations (3) and (4), the integrated digital signal SI can be further converted into a time-dependent signal. By selecting a separation time point TS, a portion of the integrated digital signal SI earlier than the separation time point TS can include information corresponding to the characteristic signal SE, and another portion of the integrated digital signal SI later than the separation time point TS can include information corresponding to the sensing signal SS, but the present invention is not limited thereto.

[0109] Figure 6 is a schematic diagram showing a time axis according to an embodiment of the present invention. Figure 6 As shown, the time axis may include a plurality of first intervals T1 and a plurality of second intervals T2, wherein the second intervals T2 are arranged alternately with the first intervals T1. Figure 6 In an embodiment of the present invention, the FMCW radar 100 may transmit a radar signal SF in each first interval T1, and receive a characteristic signal SE from the object 160. As described above, the first digital information SD1 may be determined by executing a first signal processing procedure, wherein the first digital information SD1 may correspond to the characteristic signal SE. In some embodiments, the first signal processing procedure includes various algorithms, such as time domain processing, frequency domain processing, or artificial intelligence machine learning. The first digital information SD1 extracted from the integrated digital signal SI may include breathing or (and) heartbeat information, but is not limited thereto.

[0110] In addition, the FMCW radar 100 can further transmit a radar signal SF in each second interval T2, and receive a sensing signal SS from the sensor 170. As described above, the second digital information SD2 can be determined by executing the second signal processing procedure, wherein the second digital information SD2 corresponds to the sensing signal SS. In some embodiments, the second signal processing procedure includes various algorithms, such as time domain processing or artificial intelligence machine learning. The second digital information SD2 extracted from the integrated digital signal SI may include information on temperature, humidity, pressure, or (and) chemical composition, but is not limited thereto.

[0111] In some embodiments, the radar signal SF in each second interval T2 may have different signal parameters from the radar signal SF in each first interval T1, such as different waveforms, different linear modulation frequencies, or different signal periods, but not limited thereto. In other words, the first interval T1 and the second interval T2 do not necessarily transmit the same radar signal SF. According to actual measurement results, this design helps to further improve the detection accuracy in the first interval T1 and the second interval T2.

[0112] In summary, the FMCW radar 100 can utilize a time multiplexing design to alternately receive, modulate, demodulate, and calculate to obtain the aforementioned characteristic signal SE and sensing signal SS.

[0113] Figure 7 is a schematic diagram showing a time axis according to an embodiment of the present invention. Figure 7 and Figure 6 Similar. Figure 7 As shown, the time axis may include a plurality of first intervals T1 and a plurality of second intervals T2, wherein the aforementioned first intervals T1 may appear continuously, and the aforementioned second intervals T2 may also appear continuously, but it is not limited thereto. Figure 7 The time multiplexing design is used to respectively receive, modulate, demodulate, and calculate to obtain the aforementioned characteristic signal SE and sensing signal SS.

[0114] Figure 8 : is a flow chart showing a detection method of a frequency modulated continuous wave radar according to an embodiment of the present invention. First, in step S810, a radar signal is generated by a chirp signal generator. In step S820, the radar signal is transmitted to an object, wherein the object has a sensor. In step S830, a reflection signal is received from the object, wherein the reflection signal includes a characteristic signal and a sensing signal. In step S840, an integrated digital signal is generated based on the reflection signal and the radar signal. Finally, in step S850, the integrated digital signal is analyzed to obtain a first digital information and a second digital information, wherein the first digital information corresponds to the characteristic signal, and the second digital information corresponds to the sensing signal. It must be understood that the above steps do not need to be performed in sequence, but Figure 1-Figure 7 Each feature of the embodiment of the present invention can be applied to Figure 8 of detection methods.

[0115] The present invention provides a novel frequency modulated continuous wave radar and detection method. Compared with the traditional design, the present invention has at least the advantages of improving detection accuracy, simplifying the overall circuit complexity, and reducing the related manufacturing cost, so it is very suitable for application in various devices.

[0116] It is worth noting that the above-mentioned component parameters are not limiting conditions of the present invention. Designers can adjust these setting values ​​according to different needs. The frequency modulated continuous wave radar and detection method of the present invention are not limited to Figure 1-Figure 8 The present invention may only include Figure 1-Figure 8 In other words, not all the features shown in the figure need to be implemented in the FMCW radar and detection method of the present invention at the same time.

[0117] The method of the present invention, or a specific form or part thereof, may exist in the form of program code. The program code may be contained in a physical medium, such as a floppy disk, an optical disk, a hard disk, or any other machine-readable (such as computer-readable) storage medium, or a computer program product not limited to an external form, wherein when the program code is loaded and executed by a machine, such as a computer, the machine becomes a device for participating in the present invention. The program code may also be transmitted through some transmission media, such as wires or cables, optical fibers, or any transmission mode, wherein when the program code is received, loaded and executed by a machine, such as a computer, the machine becomes a device for participating in the present invention. When implemented on a general-purpose processing unit, the program code combines with the processing unit to provide a unique device that operates similarly to an application-specific logic circuit.

[0118] Ordinal numbers in this specification and claims, such as "first", "second", "third", etc., have no sequential relationship with each other and are only used to distinguish two different elements with the same name.

[0119] Although the present invention is disclosed as above with preferred embodiments, it is not intended to limit the scope of the present invention. Anyone skilled in the art may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A frequency modulated continuous wave radar for detecting an object having a sensor, comprising: a chirp signal generator, generating a radar signal; a transmitting module, transmitting the radar signal to the object; a receiving module, receiving a reflected signal from the object, wherein the reflected signal includes a characteristic signal and a sensing signal; a processing module for generating an integrated digital signal according to the reflected signal and the radar signal; and a computing module, analyzing the integrated digital signal to obtain a first digital information and a second digital information; The first digital information corresponds to the characteristic signal, and the second digital information corresponds to the sensing signal.

2. The FMCW radar as claimed in claim 1, wherein the sensor is a surface acoustic wave sensor.

3. The FMCW radar as claimed in claim 1, wherein the processing module comprises: a frequency modulated continuous wave demodulator, generating an intermediate frequency signal according to the reflected signal and the radar signal; as well as An analog-to-digital converter converts the intermediate frequency signal into the integrated digital signal. 4 . The FMCW radar as claimed in claim 3 , wherein the intermediate frequency signal comprises a first frequency difference between the characteristic signal and the radar signal, and a second frequency difference between the sensing signal and the radar signal.

5. The FMCW radar as claimed in claim 1, wherein the operation module comprises: a Fourier transform unit, executing a range fast Fourier transform process and a Doppler fast Fourier transform process on the integrated digital signal to generate a transform result; as well as An analyzing unit analyzes the conversion result to obtain the first digital information and the second digital information. 6 . The FMCW radar as claimed in claim 1 , wherein the operation module determines the integrated digital signal into the first digital information and the second digital information according to a separation time point. 7 . The FMCW radar as claimed in claim 1 , wherein the operation module determines the integrated digital signal into the first digital information and the second digital information according to a separation frequency point. 8 . The FMCW radar as claimed in claim 1 , wherein the chirp signal generator provides the radar signal with different signal parameters in a first interval and a second interval.

9. The FMCW radar as claimed in claim 1, wherein the first digital information includes breathing and / or heartbeat information.

10. The FMCW radar as claimed in claim 1, wherein the second digital information comprises information of temperature, humidity, pressure, or / and chemical composition.

11. A detection method of a frequency modulated continuous wave radar, comprising: Generating a radar signal by a chirp signal generator; transmitting the radar signal to an object, wherein the object has a sensor; receiving a reflection signal from the object, wherein the reflection signal includes a characteristic signal and a sensing signal; generating an integrated digital signal according to the reflected signal and the radar signal; as well as The integrated digital signal is analyzed to obtain a first digital information and a second digital information, wherein the first digital information corresponds to the characteristic signal, and the second digital information corresponds to the sensing signal.

12. The detection method of FMCW radar as claimed in claim 11, wherein the sensor is a surface acoustic wave sensor.

13. The detection method of FMCW radar as claimed in claim 11, further comprising: generating an intermediate frequency signal according to the reflected signal and the radar signal by a frequency modulated continuous wave demodulator; as well as The intermediate frequency signal is converted into the integrated digital signal by an analog-to-digital converter. 14 . The detection method of FMCW radar as claimed in claim 13 , wherein the intermediate frequency signal comprises a first frequency difference between the characteristic signal and the radar signal, and a second frequency difference between the sensing signal and the radar signal.

15. The detection method of FMCW radar as claimed in claim 11, further comprising: Performing a range fast Fourier transform process and a Doppler fast Fourier transform process on the integrated digital signal to generate a transformation result; as well as The conversion result is analyzed to obtain the first digital information and the second digital information.

16. The detection method of FMCW radar as claimed in claim 11, further comprising: The integrated digital signal is determined to be the first digital information and the second digital information according to a separation time point.

17. The detection method of FMCW radar as claimed in claim 11, further comprising: The integrated digital signal is determined to be the first digital information and the second digital information according to a separation frequency point.

18. The detection method of FMCW radar as claimed in claim 11, further comprising: The radar signal having different signal parameters is provided in a first interval and in a second interval.

19. The detection method of FMCW radar as claimed in claim 11, wherein the first digital information includes breathing and / or heartbeat information.

20. The detection method of FMCW radar as claimed in claim 11, wherein the second digital information comprises information of temperature, humidity, pressure, or / and chemical composition.

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