TWI543750B - Microwave imaging method and microwave imaging system and bone-assessment method using the same - Google Patents

Description

Microwave imaging method and imaging system and bone evaluation method thereof

The present invention relates to an imaging method and application thereof, and in particular to a microwave imaging method and an imaging system and bone evaluation method using the same.

In recent years, in the existing bone evaluation techniques, in order to be able to accurately assess the condition of bone tissue in the body (such as bone density, bone structure, strength and easy fracture location), there have been many different forms of energy scanning/imaging methods (eg Ultrasonic, X-ray, MRI) are widely used.

In most cases, however, the imaging modality does not provide a consistent analysis of the complete data for bone characteristics. In addition, as far as current technology is concerned, most of the techniques used in signal processing techniques are used to obtain available data in a simplified manner, and the signal-to-noise ratio (SNR) of the experimental data is relatively poor. The most important factor is the lack of information on bone density, such as the effects of soft tissue and muscle tissue, and high-cost imaging.

The invention provides a microwave imaging method and an imaging system and a bone evaluation method thereof, which can adopt a non-free radiation type microwave scanning method to obtain high-accuracy bone composition characteristics and three-dimensional tomographic images.

The microwave imaging method of the present invention comprises the steps of: transmitting a plurality of microwave signals having different frequencies; receiving a plurality of scattered field data generated based on the plurality of microwave signals; calculating the object to be measured at a corresponding frequency according to each of the scattered field data Dielectric coefficient distribution, wherein the dielectric coefficient distributions corresponding to different frequencies have different resolution depths; corresponding tomographic image data are generated according to respective dielectric coefficient distributions; and the object to be measured is established based on the plurality of tomographic images Three-dimensional tomographic image.

In an embodiment of the invention, the plurality of microwave signals transmitted have a frequency range between 1 GHz and 10 GHz.

In an embodiment of the invention, each of the scattered field data includes a plurality of scattered signals received at different receiving locations. The step of calculating the dielectric coefficient distribution of the object to be tested at the corresponding frequency according to each of the scattered field data includes: performing Fourier transform on the plurality of scattered signals respectively when the plurality of scattered signals are received at the first frequency (Fourier transform), thereby generating an admittance function of the object to be tested with respect to the corresponding receiving position; calculating a dielectric coefficient of the object to be tested at the corresponding receiving position according to the admittance function; and according to the plurality of receiving positions The dielectric constant establishes a distribution of dielectric coefficients of the object to be measured at the first frequency.

In an embodiment of the invention, the microwave imaging method further comprises the steps of: selecting a region of interest (ROI) of the three-dimensional tomographic image; Adjusting signal characteristics of the plurality of microwave signals transmitted; obtaining a distribution of dielectric coefficients corresponding to different signal characteristics of the target region; and establishing a trend of dielectric coefficient characteristics of the object to be tested according to a distribution of dielectric coefficients in the target region .

In an embodiment of the invention, the microwave imaging method further comprises the steps of: obtaining a trend of abnormal dielectric constant characteristics; and determining an object to be measured according to a trend of a dielectric coefficient characteristic of the object to be measured and a trend of an abnormal dielectric coefficient characteristic; Is the composition normal?

In an embodiment of the invention, the step of determining whether the composition of the object to be tested is normal according to the trend of the dielectric coefficient characteristic of the object to be measured and the trend of the abnormal dielectric coefficient characteristic comprises: calculating a characteristic of the dielectric coefficient characteristic and an abnormal dielectric constant characteristic The degree of correlation of the trend; whether the degree of correlation is greater than or equal to the critical criterion; when the degree of correlation is greater than or equal to the critical criterion, the composition of the object to be tested is determined to be abnormal; and when the degree of correlation is less than the critical criterion, the composition of the object to be tested is determined to be normal.

In an embodiment of the invention, the signal characteristic includes at least one of a wavelength, an amplitude, and a power of the plurality of microwave signals.

In an embodiment of the invention, the frequency of the microwave signal is inversely related to the resolution depth.

The microwave imaging system of the present invention comprises a signal transceiving module, a control unit and a display unit. The signal transceiver module is configured to transmit a plurality of microwave signals having different frequencies, and receive a plurality of scattered field data generated based on the plurality of microwave signals. The control unit is configured to control the operation of the signal transceiving module, and generate a three-dimensional tomographic image of the object to be tested according to the plurality of scattered field data. Display unit for displaying three-dimensional breaks Layer image. The control unit calculates the dielectric coefficient distribution of the object to be tested at the corresponding frequency according to each scattered field data, and then generates tomographic image data having a corresponding resolution depth according to the dielectric coefficient distribution of different frequencies, thereby based on the plurality of said faults The image data establishes a three-dimensional tomographic image of the object to be measured.

In an embodiment of the invention, the frequency of the microwave signal transmitted by the signal transceiver module ranges from 1 GHz to 10 GHz.

In an embodiment of the invention, the signal transceiver module includes a signal processing unit, a transmitting antenna, and a receiving antenna. The signal processing unit is configured to generate the plurality of microwave signals having different frequencies. The transmit antenna receives from the signal processing unit and sequentially transmits the plurality of microwave signals. The receiving antenna is configured relative to the transmitting antenna to receive the plurality of scattered field data generated based on the plurality of microwave signals, and transmit the plurality of scattered field data back to the control unit.

In an embodiment of the invention, the microwave imaging system further includes a positioning platform. The positioning platform is configured to be movably disposed on the positioning platform, and the receiving antenna is controlled by the control unit to move along the scanning path on the positioning platform, thereby receiving a plurality of scattered signals at different receiving positions on the scanning path. The control unit uses the plurality of scattered signals received by the receiving antenna at the first frequency as the scattered field data corresponding to the first frequency.

In an embodiment of the invention, when the control unit receives the plurality of scattered signals at the first frequency, the control unit respectively performs Fourier transform on the plurality of scattered signals, thereby generating an object to be tested relative to the corresponding receiving The admittance function at the position calculates the dielectric coefficient of the object to be tested at the corresponding receiving position according to the admittance function. And establishing a dielectric coefficient distribution of the object to be tested at the first frequency according to the dielectric coefficients at the plurality of receiving locations.

In an embodiment of the invention, the signal transceiver module adjusts the signal characteristics of the plurality of microwave signals transmitted, so that the control unit obtains the distribution of the dielectric coefficients corresponding to the target regions under different signal characteristics, thereby establishing a test to be tested. The trend of the dielectric coefficient characteristics of an object.

In an embodiment of the invention, the control unit determines whether the composition of the object to be tested is normal according to the trend of the dielectric coefficient characteristic of the object to be measured and the trend of the abnormal dielectric coefficient characteristic.

In an embodiment of the invention, the control unit calculates the correlation degree between the trend of the dielectric coefficient characteristic and the trend of the abnormal dielectric coefficient characteristic, and then determines whether the correlation degree is greater than or equal to the critical criterion; when the correlation degree is greater than or equal to the critical criterion, determining the object to be tested The composition is abnormal; and when the degree of correlation is less than the critical criterion, it is determined that the composition of the object to be tested is normal.

In an embodiment of the invention, the signal characteristic includes at least one of a wavelength, an amplitude, and a power of the plurality of microwave signals.

The bone quality evaluation method of the present invention comprises the following steps: transmitting a microwave signal to the object to be measured; calculating a dielectric coefficient distribution of the object to be tested according to the scattered field data generated by the microwave signal, and establishing a three-dimensional tomographic image of the object to be tested according to the method; Adjusting a signal characteristic of the plurality of microwave signals to be transmitted; obtaining a dielectric coefficient distribution corresponding to the three-dimensional tomographic image under different signal characteristics; establishing a dielectric of the object to be tested according to the obtained plurality of dielectric coefficient distributions Coefficient characteristic trend; and based on the object to be tested The tendency of the dielectric coefficient characteristic and the characteristic of the abnormal dielectric coefficient, and determine whether the bone composition of the object to be tested is normal.

In an embodiment of the present invention, the bone evaluation method further comprises the steps of: selecting an osseous tissue region of the three-dimensional tomographic image; and obtaining a dielectric coefficient distribution corresponding to the different signal characteristics of the bone tissue region; The dielectric coefficient characteristic trend of the object to be tested is established according to the distribution of the dielectric coefficient in the bone tissue region.

Based on the above, the embodiment of the present invention provides a microwave imaging method and an imaging system and a bone evaluation method thereof. The microwave imaging method can construct a three-dimensional tomographic image and composition characteristic information of the object to be tested by calculating the dielectric constant distribution of the scattered field data at different microwave frequencies. Thereby, the microwave imaging method of the embodiment of the invention can analyze the composition characteristics of the object to be tested and the three-dimensional tomographic image by detecting the non-free radiation of the human body. In addition, the bone evaluation method of the embodiment of the present invention can establish the trend of the dielectric coefficient characteristic of the bone to be tested by adjusting the signal characteristics of the microwave signal, thereby more accurately determining whether the bone quality to be tested is normal.

The above described features and advantages of the invention will be apparent from the following description.

100, 600‧‧‧ microwave imaging system

110, 610‧‧‧ Signal Transceiver Module

112, 614‧‧‧ transmit antenna

114, 616‧‧‧ receiving antenna

120, 620‧‧‧ control unit

130, 630‧‧‧ display unit

612‧‧‧Signal Processing Unit

640‧‧‧Targeting platform

Trend of dielectric coefficient characteristics of CP1, CP2‧‧

DUT‧‧‧ objects to be tested

D1‧‧‧Dielectric coefficient

F1~fn‧‧‧frequency

TG1~TGn, TGa1~TGam‧‧‧ tomographic images

3DTG, 3DTG1'~3DTGm'‧‧‧3D tomography

ROI‧‧ target area

S210~S250, S410~S460‧‧‧ steps

x, y‧‧‧ receiving location

1 is a functional block diagram of a microwave imaging system according to an embodiment of the present invention.

2 is a flow chart showing the steps of a microwave imaging method according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of establishing a three-dimensional tomographic image of an object to be tested by using the step flow of the embodiment of FIG. 2. FIG.

4 is a flow chart showing the steps of a bone evaluation method according to an embodiment of the present invention.

5A and 5B are schematic diagrams of bone evaluation using the step flow of the embodiment of FIG. 4.

FIG. 6 is a schematic structural diagram of a system of a microwave imaging system according to an embodiment of the present invention.

In order to make the disclosure of the present disclosure easier to understand, the following specific embodiments are examples of the disclosure that can be implemented. In addition, wherever possible, the same elements, components, and steps in the drawings and embodiments are used to represent the same or similar components.

1 is a functional block diagram of a microwave imaging system according to an embodiment of the present invention. Referring to FIG. 1 , the microwave imaging system 100 of the present embodiment can acquire the tomographic image data of the DUT of the object to be tested by means of microwave scanning, and establish a three-dimensional tomographic image of the DUT of the object to be tested according to the obtained tomographic image data, thereby The composition of the DUT of the object to be tested is presented by means of an image. The microwave imaging system 100 can be used for bone quality detection/evaluation of human body, material structure property detection of industrial materials (such as screws, rubber, gaskets, etc.), and detection of agricultural product components (for example, meat fat content detection, fruit internal non-destructive detection) Or other non-invasive physiological testing applications.

The microwave imaging system 100 includes a signal transceiving module 110, a control unit 120, and a display unit 130. In this embodiment, the signal transceiver module 110 can be used to transmit The transmitting antenna 112 transmits a microwave signal toward the object to be tested DUT, wherein the transmitted microwave signal is penetrated/scattered according to the size and composition of the DUT of the object to be tested, thereby generating a plurality of characteristic characteristics associated with the DUT of the object to be tested. Scattering signal. The signal transceiver module 110 then receives the plurality of scattered signals by the receiving antenna 114 as the scattered field data at the corresponding microwave frequency, and then transmits the scattered field data to the control unit 120 at the back end for processing. The transmit antenna 112 and the receive antenna 114 may be, for example, a monopole antenna, a linear antenna, a matrix antenna, or other types of antennas, and the invention is not limited thereto.

The control unit 120 can be used to control the operation of the signal transceiving module 110 and perform operations according to the scattered field data to obtain a dielectric coefficient associated with the DUT of the object to be tested. Thereafter, the control unit 120 performs image restoration analysis according to the calculated dielectric coefficient, thereby generating a three-dimensional tomographic image of the DUT of the object to be tested. The control unit 120 can be a hardware circuit with a logic operation capability, such as a central processing unit (CPU), a microcontroller (MCU), and the like, and the invention is not limited thereto.

The display unit 130 is coupled to the control unit 120 for displaying the three-dimensional tomographic image established by the control unit 120. The display unit 130 can be, for example, a flat panel display (such as an LCD display, an LED display) or a projection display, and the like, and the invention is not limited thereto. In addition, in an exemplary embodiment, the display unit 130 may also have a function of touch sensing. The user can click on a specific region of interest (ROI) in the three-dimensional tomographic image displayed by the display unit 130, so that the control unit 120 can reflect the image/data of the target region in response to the touch operation of the user. It is presented on the display unit 130, but the invention is also not limited thereto.

The flow of the steps of imaging with the microwave imaging system 100 described above will be further described below with reference to FIG. 2 is a flow chart of steps of a microwave imaging method according to an embodiment of the present invention.

Referring to FIG. 1 and FIG. 2 simultaneously, first, the signal transceiver module 110 transmits a plurality of microwave signals having different frequencies toward the object DUT to be tested (step S210), wherein the microwave signal at each frequency is based on the DUT of the object to be tested. The shape and composition produce a corresponding set of scattering field data. The signal transceiver module 110 receives the plurality of scattered field data generated based on the microwave signal (step S220), and transmits the scattered field data back to the control unit 120.

Then, after receiving the scattered field data, the control unit 120 calculates the dielectric coefficient distribution of the DUT of the object to be tested at the corresponding frequency according to each set of scattered field data (step S230), and then generates according to the distribution of the respective dielectric coefficients. Corresponding tomographic image data (step S240). Based on this, the control unit 120 can create a three-dimensional tomographic image based on the generated tomographic image data (step S250).

In detail, the microwave signals of different frequencies have different penetration capabilities, and the difference in penetration capability causes the control unit 120 to have different resolution depths based on the distribution of the dielectric coefficients resolved by the scattered field data. By the difference in the resolution depth, the control unit 120 can generate tomographic images of different depths at different microwave signal frequencies. More specifically, in the embodiment, the frequency range of the microwave signal transmitted by the signal transceiver module 110 is substantially between 1 GHz and 10 GHz. In this frequency range, the resolution depth of the dielectric coefficient distribution is substantially negative with the frequency of the microwave signal. Correlation, that is, the higher the frequency, the lower the penetration capability of the microwave signal, so that the depth of the DUT of the object to be tested that the control unit 120 can analyze based on the dielectric coefficient distribution is shallower.

For example, when the signal transceiver module 110 transmits a microwave signal of 10 GHz, the control unit 120 may calculate a dielectric coefficient distribution indicating a depth of about 1 cm from the surface of the DUT of the object to be tested according to the scattered field data. On the other hand, when the frequency of the microwave signal transmitted by the signal transceiver module 110 is getting lower and lower, the penetration capability of the microwave signal is enhanced, so that the resolution depth of the dielectric coefficient distribution at the corresponding frequency is gradually increased. . Therefore, the control unit 120 can obtain tomographic image data of different depths accordingly.

In other words, in the present embodiment, the signal transceiver module 110 can transmit microwave signals of different frequencies by means of frequency scanning, so that the control unit 120 can obtain a dielectric coefficient distribution having different resolution depths. Therefore, the control unit 120 can calculate the tomographic image data of the DUT of the object to be tested at different depths according to the distribution of the dielectric coefficients representing the composition characteristics of the object DUT at different depths, thereby establishing the DUT of the object to be tested. Three-dimensional tomographic image.

Since the microwave imaging system and method of the embodiment of the present invention does not use the free-radiation detection method, compared with the conventional free-radiation imaging method (for example, X-ray scanning, computed tomography (CT)), The microwave imaging system and method can remove the harm of radiation to the human body. In addition, compared with other non-free radiation imaging methods such as ultrasonic waves, the microwave imaging system generates corresponding tomographic image data by detecting the distribution of dielectric coefficients at different microwave frequencies, and thus The composition characteristics of the object DUT have higher resolution and resolution.

In order to more clearly illustrate the above-described microwave imaging method, FIG. 3 is a schematic diagram of establishing a three-dimensional tomographic image of an object to be tested by using the step flow of the embodiment of FIG. 2.

Referring to FIG. 3, first, the transmitting antenna 112 in the signal transmitting and receiving module 110 sends a microwave signal Smic with a frequency f1 toward the object DUT, and the receiving antenna 114 receives multiple DUTs penetrating the object to be tested at different receiving positions. The resulting scattered signal Ssca, and the scattered signals Ssca received by the plurality of different receiving locations can form a set of scattered field data corresponding to the frequency f1.

When the control unit 120 receives a set of scattered field data at the frequency f1, the control unit 120 performs Fourier transform on the scattered signal Ssca corresponding to each receiving position, thereby generating the DUT of the object to be tested relative to the corresponding receiving position. Admittance function. Next, the control unit 120 calculates the dielectric coefficient of the object to be tested DUT at the corresponding receiving position according to the admittance function. For example, the dielectric coefficient of the DUT of the object to be tested can be calculated as D1 at the receiving position (x, y).

By calculating the dielectric coefficient, the control unit 120 can calculate the corresponding dielectric coefficient at each receiving position on the receiving antenna 114 one by one, thereby establishing the dielectric coefficient distribution of the DUT of the object to be tested at the frequency f1. . Therefore, the control unit 120 can generate tomographic image data corresponding to the frequency f1 according to the established dielectric coefficient distribution (this is represented by the corresponding tomographic image TG1).

After the control unit 120 establishes the tomographic image data at the frequency f1, the signal transceiver module 110 successively adjusts the frequency of the microwave signal Smic to f2~fn (n is a positive integer), and the control unit 120 repeats Based on the above actions, tomographic image data corresponding to the frequency f2~fn and its tomographic image are established. TG2~TFn. Accordingly, the control unit 120 can establish the three-dimensional tomographic image 3DTG of the object DUT to be measured according to the tomographic image data corresponding to the tomographic images TG1 to TGn.

The microwave imaging system and method can be further applied to a bone evaluation method, and the specific step flow thereof is shown in FIG. 4 . 4 is a flow chart showing the steps of a bone evaluation method according to an embodiment of the present invention.

Referring to FIG. 1 and FIG. 4 simultaneously, in this embodiment, first, the signal transceiver module 110 transmits a microwave signal to the object DUT (here, for example, a human body) (step S410), and then the control unit 120 is based on the microwave signal. The generated scattered field data is used to calculate a dielectric coefficient distribution of the DUT of the object to be measured, and a three-dimensional tomographic image of the DUT of the object to be tested is established (step S420). For the specific operations of the above-mentioned steps S410 and S420 for establishing the three-dimensional tomographic image of the object DUT to be tested, reference may be made to the description of FIG. 1 to FIG. 3 above.

Thereafter, the signal transceiver module 110 is controlled by the control unit 120 to adjust the signal characteristics of the transmitted microwave signals (step S430), so that the control unit 120 obtains the dielectric coefficient distribution corresponding to the three-dimensional tomographic image under different signal characteristics. (Step S440). The signal characteristics described herein may be, for example, the wavelength, amplitude, and/or power of the microwave signal.

After obtaining the corresponding dielectric coefficient distribution of the three-dimensional tomographic image under different signal characteristics, the control unit 120 further establishes the dielectric coefficient characteristic trend of the DUT of the object to be tested according to the obtained dielectric coefficient distribution under different signal characteristics ( Step S450), and determining whether the bone composition of the object to be tested is normal according to the trend of the dielectric coefficient characteristic of the DUT of the object to be tested and the trend of an abnormal dielectric coefficient characteristic (step S460).

In the present embodiment, the tendency of the abnormal dielectric constant characteristic can be established by a clinical experiment to obtain a series of dielectric coefficient distribution characteristics obtained by osteoporosis patients under the same processing conditions, but the present invention is not limited thereto.

In order to more clearly illustrate the microwave imaging method described above, FIGS. 5A and 5B are schematic diagrams of bone evaluation using the step flow of the embodiment of FIG. 4.

Referring to FIG. 5A, in the embodiment, the control unit 120 obtains the three-dimensional tomographic image 3DTG1' of the selected target region in different states by changing the signal characteristics of the microwave signal transmitted by the signal transceiver module 110. 3DTGm' (m is a positive integer).

The user can select the region of interest as the target region ROI after establishing the three-dimensional tomographic image 3DTG of the DUT of the object to be tested. More specifically, in the bone evaluation method, since the established three-dimensional bone image not only indicates the compositional characteristics of the osseous tissue, it also contains various other tissue components. Therefore, the user can select the bone tissue region as the target region ROI, so that the control unit 120 can analyze the dielectric coefficient distribution in the target region ROI to obtain more effective bone material. Here, the dielectric coefficient distribution of the selected target region ROI corresponds to the tomographic image TGa as an example.

After the user selects a specific target area ROI, the control unit 120 further obtains the dielectric coefficient distribution (corresponding to the tomographic images TGa1 to TGam) in the target area ROI of the three-dimensional tomographic images 3DTG1'~3DTGm' under different signal characteristics. Then, the distribution of the dielectric coefficients corresponding to the different signal characteristics of the target region is obtained. After that, the control unit 120 can establish a trend of the dielectric coefficient characteristics of the object to be tested according to the distribution of the dielectric coefficient.

More specifically, since the structurally normal bone has a tighter bone structure, that is, the porosity/hole volume between the bone tissues is less; on the contrary, for osteoporosis patients, the pores between the bone tissues The rate/hole volume will be higher. Therefore, normal bone should have a higher dielectric constant than abnormal bone. Based on this characteristic, the control unit 120 can determine whether the bone composition of the DUT of the object to be tested is normal according to the trend of the dielectric coefficient characteristic and the characteristic of the abnormal dielectric coefficient of the DUT of the object to be tested.

For example, the control unit 120 may calculate the degree of correlation between the trend of the dielectric coefficient characteristic and the trend of the abnormal dielectric coefficient characteristic by a machine learning method (for example, a statistical method or a neural network-like algorithm, etc.), and determine the calculated correlation degree. Whether it is greater than or equal to a specific critical criterion (can be set by the designer). If the control unit 120 determines that the calculated correlation degree is greater than or equal to the critical criterion, it determines that the composition of the object to be tested DUT is abnormal; otherwise, if the control unit 120 determines that the calculated correlation degree is less than the critical criterion, then determines the DUT of the object to be tested. The composition is normal.

As shown in FIG. 5B, the trend of the dielectric coefficient characteristic CP1 of normal bone and the dielectric characteristic characteristic CP2 of abnormal bone are taken as an example. From normal bone tomography and abnormal bone tomography (osteoporosis), it can be found that the bone density of normal bone is higher (that is, the porosity/hole volume of the bone group is less), so the normal bone is below different frequencies. The dielectric coefficient characteristic trend CP1 will be higher than the abnormal stock value dielectric characteristic characteristic trend CP2. Therefore, the control unit compares the dielectric constant shown in FIG. 5B. The difference between the sexual trend CP1 and CP2 can accurately determine whether the bone of the DUT of the object to be tested is normal.

FIG. 6 is a schematic structural diagram of a system of a microwave imaging system according to an embodiment of the present invention. Referring to FIG. 6 , the microwave imaging system 600 of the present embodiment includes a signal transceiving module 610 , a control unit 620 , a display unit 630 , and a positioning platform 640 . The signal transceiver module 610 further includes a signal processing unit 612, a transmitting antenna 614, and a receiving antenna 616.

The signal processing unit 612 can be used to generate microwave signals Smic having different frequencies. The transmitting antenna 614 is illustrated as a matrix antenna (but not limited thereto), and receives the microwave signal Smic of different frequencies from the signal processing unit 612. The receiving antenna 616 is illustrated here as a monopole antenna, but is not limited thereto, and is movably disposed on the positioning platform 640 with respect to the transmitting antenna 614. The receiving antenna 616 can be configured to receive the scattered field data (composed of the plurality of scattered signals Ssca) generated based on the microwave signal Smic, and transmit the scattered field data back to the control unit 620.

In this embodiment, the control unit 620 controls the receiving antenna 616 to move along a specific scanning path (such as an arrow direction) on the positioning platform 640, thereby sequentially receiving a plurality of scattered signals Ssca at different receiving positions on the scanning path. The control unit 620 uses the scattered signal Ssca obtained on the next scan path cycle at a specific frequency as a set of scattered field data.

It is worth mentioning here that the setting of the scan path can be changed according to the type of the receiving antenna 616. For example, if the receiving antenna 616 is a linear antenna, the receiving antenna 616 only needs to receive the scattered signal Ssca in a straight scanning path. The complete scattering field data can be received. Alternatively, if the receiving antenna 616 is a matrix antenna, the receiving antenna 616 can be fixed to the positioning platform 640 without receiving movement along the scanning path to receive the complete scattered field data.

The invention mainly uses a non-free radiation method to diagnose the bone health condition, and uses the bone content and the stereoscopic image obtained by the microwave image to determine the bone health condition.

In summary, the embodiments of the present invention provide a microwave imaging method and an imaging system and a bone evaluation method thereof. The microwave imaging method can construct a three-dimensional tomographic image and composition characteristic information of the object to be tested by calculating the dielectric constant distribution of the scattered field data at different microwave frequencies. Thereby, the microwave imaging method of the embodiment of the invention can analyze the composition characteristics of the object to be tested and the three-dimensional tomographic image by detecting the non-free radiation of the human body. In addition, the bone evaluation method of the embodiment of the present invention can establish the trend of the dielectric coefficient characteristic of the bone to be tested by adjusting the signal characteristics of the microwave signal, thereby more accurately determining whether the bone quality to be tested is normal.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

S210~S250‧‧‧Steps

Claims (20)

A microwave imaging method includes: transmitting a plurality of microwave signals having different frequencies; receiving a plurality of scattered field data generated based on the microwave signals; and calculating, based on the scattered field data, an object to be measured at a corresponding frequency An electric coefficient distribution, wherein the dielectric coefficient distributions corresponding to different frequencies respectively have different resolution depths; generating a corresponding tomographic image data according to each of the dielectric coefficient distributions; and establishing one of the objects to be tested based on the tomographic image data Three-dimensional tomographic image. The microwave imaging method according to claim 1, wherein the frequency of the microwave signals emitted ranges from 1 GHz to 10 GHz. The microwave imaging method of claim 1, wherein each of the scattered field data comprises a plurality of scattered signals received at different receiving positions, and the object to be tested is calculated according to each of the scattered field data at a corresponding frequency. The step of the dielectric coefficient distribution includes: performing a Fourier transform on the scattered signals when receiving the scattered signals at a first frequency, thereby generating the object to be tested relative to the corresponding receiving position An admittance function; calculating a dielectric coefficient of the object to be tested at a corresponding receiving position according to the admittance function; and establishing the object to be tested at the first frequency according to the dielectric coefficient at the receiving positions Dielectric coefficient distribution. The microwave imaging method of claim 1, further comprising: selecting a region of interest (ROI) of the three-dimensional tomographic image; adjusting a signal characteristic of the transmitted microwave signals; and obtaining the target The distribution of the dielectric coefficient corresponding to the different signal characteristics of the region; and establishing a dielectric characteristic characteristic of the object to be tested according to the distribution of the dielectric coefficients in the target region. The microwave imaging method according to claim 4, further comprising: obtaining an abnormal dielectric constant characteristic trend; and determining the waiting according to the trend of the dielectric coefficient characteristic of the object to be tested and the characteristic of the abnormal dielectric coefficient characteristic Check if the composition of the object is normal. The microwave imaging method according to claim 5, wherein the step of determining whether the composition of the object to be tested is normal according to the trend of the dielectric coefficient characteristic of the object to be tested and the trend of the abnormal dielectric coefficient characteristic comprises: calculating the a degree of correlation between a trend of the dielectric coefficient characteristic and a trend of the characteristic property of the abnormal dielectric coefficient; determining whether the correlation degree is greater than or equal to a critical criterion; and determining that the composition of the object to be tested is abnormal when the correlation degree is greater than or equal to the critical criterion; When the degree of correlation is less than the critical criterion, it is determined that the composition of the object to be tested is normal. The microwave imaging method according to claim 4, wherein the signal is The characteristics include at least one of wavelength, amplitude, and power of the microwave signals. The microwave imaging method according to claim 1, wherein the frequency of the microwave signal is negatively correlated with the depth of analysis. A microwave imaging system includes: a signal transceiver module for transmitting a plurality of microwave signals having different frequencies, and receiving a plurality of scattered field data generated based on the microwave signals; and a control unit for controlling the signal The operation of the transceiver module, and generating a three-dimensional tomographic image of the object to be tested according to the scattered field data; and a display unit coupled to the control unit for displaying the three-dimensional tomographic image, wherein the control unit is configured according to each The scattering field data calculates a dielectric coefficient distribution of the object to be tested at a corresponding frequency, and then generates tomographic image data having a corresponding resolution depth according to the dielectric coefficient distribution of different frequencies, thereby establishing based on the tomographic image data. A three-dimensional tomographic image of the object to be tested. The microwave imaging system of claim 9, wherein the frequency of the microwave signal emitted by the signal transceiver module ranges from 1 GHz to 10 GHz. The microwave imaging system of claim 9, wherein the signal transceiver module comprises: a signal processing unit for generating the microwave signals having different frequencies; and a transmitting antenna coupled to the signal processing unit, Receiving and sequentially transmitting the microwave signals from the signal processing unit; and receiving antennas, relative to the transmit antenna configuration, for receiving the micro signals based on the The scattered field data generated by the wave signal, and the scattered field data is returned to the control unit. The microwave imaging system of claim 11, further comprising: a positioning platform, the receiving antenna is movably disposed on the positioning platform, and the receiving antenna is controlled by the control unit on the positioning platform a scanning path is moved to receive a plurality of scattered signals at different receiving positions on the scanning path, wherein the control unit receives the scattered signals received by the receiving antenna at a first frequency as corresponding to the first Frequency scattering field data. The microwave imaging system of claim 12, wherein when the control unit receives the scattered signals at the first frequency, the control unit performs a Fourier transform on the scattered signals, thereby generating the Calculating, according to the admittance function, a dielectric coefficient of the object to be tested at a corresponding receiving position according to an admittance function on the corresponding receiving position, and establishing the waiting according to the dielectric coefficient at the receiving positions Measuring the dielectric coefficient distribution of the object at the first frequency. The microwave imaging system of claim 9, wherein the signal transceiver module adjusts a signal characteristic of the emitted microwave signals, so that the control unit obtains a corresponding region of the target region under different signal characteristics. The electric coefficient is distributed to establish a trend of a dielectric coefficient characteristic of the object to be tested. The microwave imaging system of claim 14, wherein the control unit determines whether the composition of the object to be tested is normal according to a trend of a dielectric coefficient characteristic of the object to be tested and a trend of an abnormal dielectric coefficient characteristic. The microwave imaging system of claim 15, wherein the control The unit calculates a correlation degree between the trend of the dielectric coefficient characteristic and the trend of the abnormal dielectric coefficient characteristic, and determines whether the correlation degree is greater than or equal to a critical criterion; when the correlation degree is greater than or equal to the critical criterion, determining the object to be tested The composition is abnormal; and when the degree of correlation is less than the critical criterion, it is determined that the composition of the object to be tested is normal. The microwave imaging system of claim 14, wherein the signal characteristic comprises at least one of a wavelength, an amplitude, and a power of the microwave signals. A bone evaluation method includes: transmitting a microwave signal to an object to be tested; calculating a dielectric coefficient distribution of the object to be tested according to a scattering field data generated by the microwave signal, and establishing the object to be tested according to the method a three-dimensional tomographic image; adjusting a signal characteristic of the emitted microwave signals; obtaining a distribution of dielectric coefficients corresponding to the three-dimensional tomographic image under different signal characteristics; establishing the to-be-distributed according to the obtained distribution of the dielectric coefficients Measuring a dielectric characteristic characteristic trend of the object; and determining whether the bone composition of the object to be tested is normal according to the trend of the dielectric coefficient characteristic of the object to be tested and the trend of an abnormal dielectric coefficient characteristic. The bone evaluation method according to claim 18, further comprising: selecting an osseous tissue region of the three-dimensional tomographic image; and obtaining a dielectric coefficient distribution corresponding to the different signal characteristics of the bone tissue region; as well as The dielectric coefficient characteristic trend of the object to be tested is established according to the dielectric coefficient distribution in the bone tissue region. The bone evaluation method according to claim 18, wherein the step of determining whether the composition of the object to be tested is normal according to the trend of the dielectric coefficient characteristic of the object to be tested and the trend of the abnormal dielectric coefficient characteristic comprises: calculating the a degree of correlation between a trend of the dielectric coefficient characteristic and a trend of the characteristic property of the abnormal dielectric coefficient; determining whether the correlation degree is greater than or equal to a critical criterion; and determining that the composition of the object to be tested is abnormal when the correlation degree is greater than or equal to the critical criterion; When the degree of correlation is less than the critical criterion, it is determined that the composition of the object to be tested is normal.