Sensor tag, method for reading the sensor tag and sensor system with sensor tag

Abstract

Sensor tag (ST), comprehensive: a plurality of conductors (11) arranged close together and forming a resonating element (13); and a detection unit (12) which is arranged between the plurality of conductors and which has a physical property which changes due to a change in a physical quantity (BR) of an object (TB) to be detected by the detection unit.

Description

TECHNICAL AREA

[0001] The present disclosure relates to a sensor tag, a method for reading the sensor tag and a sensor system that uses the sensor tag. STATE OF THE ART

[0002] A general tag, represented by the tag described in patent literature 1, which is common to the sensor tag according to the present disclosure, has a sensing unit. The sensing unit indicates a physical quantity of an object scanned by the sensing unit by a change in a property of the sensing unit, which is based on an electromagnetic wave reflection property of the sensing unit, e.g. by a change in the dielectric constant or the conductivity, as described in patent literature 1.

[0003] Patent literature 2 discloses a device comprising several sensors for determining one of several physical properties, such as pressure, temperature, chemical composition, and other physical conditions. Generally, the sensors have a resonant circuit with an induction coil that is electromagnetically coupled to a transmitting antenna. When an excitation signal is applied to the antenna, a current is induced in the sensor circuit. This current oscillates at the resonant frequency of the sensor circuit. The resonant frequency and bandwidth of the sensor circuit are determined using an impedance analyzer, a transmitting and receiving antenna system, or a chirp interrogation system. The resonant frequency can also be determined using a simple analog circuit with a transmitter.The sensors are designed such that either the resonant frequency or the bandwidth of the sensor circuit, or both, depend on physical properties such as pressure, temperature, the presence of a chemical substance, or other conditions of a specific environment. The physical properties are calculated based on the determined resonant frequency and bandwidth.

[0004] Patent reference 3 discloses a sensor label comprising an antenna and connecting conductors formed on the surface of a flexible substrate. A sensor element is mounted on land conductors of the connecting conductors. The sensor element consists of a crystal vibrator and a RFIC. The crystal vibrator receives an external excitation signal and generates a resonant signal with a resonant frequency corresponding to the measured temperature. The RFIC stores information about the equivalent circuit constant, which includes at least an equivalent inductance or capacitance of the crystal vibrator.

[0005] Patent literature 4 discloses improved surface acoustic wave (SAW) sensors and wireless SAW sensor-tag interface devices, including low-loss devices, devices that enable improved use of time diversity for device identification, and devices suitable for use in band-limited environments (such as the ISM band) and for use in ultra-wideband applications. Antennas for use with both SAW sensors and / or tags and wireless transmit / receive systems are also disclosed, including antennas suitable for operation in conductive media and in highly metallic environments, wherein the antennas are used for activating and reading the SAW sensors and / or tags. SAW sensors and sensor tags and related methods for measuring scaled voltages and currents in electrical conductors via measurements of their electric and magnetic fields are disclosed. REFERENCE LIST PATENT LITERATURE Patent Literature 1: JP 2021-89725 A Patent literature 2: US 6,278,379 B1 Patent literature 3: US 10,234,334 B2 Patent literature 4: US 2017 / 0010308 A1 SUMMARY OF THE INVENTIONAL PROBLEM

[0006] However, the problem with the tag described above is that the detection unit described above cannot detect the physical size of the object if the dielectric constant or conductivity of the detection unit does not change, even though the physical size of the object changes.

[0007] The purpose of the present disclosure is to provide a sensor tag capable of detecting a physical quantity of an object, even if the conductivity or dielectric constant of a detection unit does not change, although the physical quantity of the object changes. SOLUTION TO THE TASK

[0008] To solve the problem described above, a sensor tag according to the present disclosure comprises a plurality of conductors arranged close together and forming a resonant element; and a sensing unit arranged between the plurality of conductors and having a physical property that changes due to a change in a physical quantity of an object to be detected by the sensing unit. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0009] With the sensor tag according to the present disclosure, a physical size of an object can be detected even if the conductivity or the dielectric constant of a detection unit does not change, although the physical size of the object changes. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 shows a configuration of a sensor tag ST of a first embodiment. Fig. Figure 2A illustrates a function (part 1 (1)) of the sensor tag ST of the first embodiment. Fig. Figure 2B illustrates a function (part 1 (2)) of the sensor tag ST of the first embodiment. Fig. Figure 2C shows a function (part 1 (3)) of the sensor tag ST of the first embodiment. Fig. Figure 3A illustrates a function (part 2 (1)) of the sensor tag ST of the first embodiment. Fig. Figure 3B illustrates a function (part 2 (2)) of the sensor tag ST of the first embodiment. Fig. Figure 4 illustrates the functionality (part 3) of the sensor tag ST of the first embodiment. Fig. Figure 5 shows a configuration (part 1) of a sensor tag ST of a second embodiment. Fig. Figure 6 shows a configuration (part 2) of the sensor tag ST of the second embodiment. Fig. Figure 7 shows a configuration (part 3) of the sensor tag ST of the second embodiment. Fig. Figures 8A to 8C are each a schematic representation showing a displacement and displacement amount of the sensor tag ST of the second embodiment. Fig. Figure 9 shows the frequency characteristic (part 1) of a reflection value of the second embodiment. Fig. Figure 10 shows the frequency characteristic (part 2) of the reflection value of the second embodiment. Fig. Figure 11 shows the frequency characteristic (part 3) of the reflection value of the second embodiment. Fig. Figure 12 shows a configuration of a sensor tag ST of a third embodiment. Fig. Figure 13 shows an electrical circuit DK of a detection unit 32 of the third embodiment. Fig. Figure 14 shows a configuration (part 1) of a fourth embodiment. Fig. Figure 15 shows a configuration (part 2) of the fourth embodiment. Fig. Figure 16 shows the frequency characteristic of a reflection value of the fourth embodiment. Fig. Figure 17 shows a configuration of a sensor tag ST of a fifth embodiment. Fig. Figure 18A shows a configuration (part 1) of a sensor tag ST of a sixth embodiment. Fig. Figure 18B shows a configuration (part 2) of the sensor tag ST of the sixth embodiment. Fig. Figure 18C shows a configuration (part 3) of the sensor tag ST of the sixth embodiment. Fig. Figure 19 shows the frequency characteristic (without shift) of a reflection value of the sixth embodiment. Fig. Figure 20 shows the frequency characteristic (shift in the X direction) of the reflection value of the sixth embodiment. Fig. Figure 21 shows the frequency characteristic (shift in the Y direction) of the reflection value of the sixth embodiment. Fig. Figure 22 shows the frequency characteristic (shift in the Z direction) of the reflection value of the sixth embodiment. Fig. Figure 23 shows an arrangement (part 1) of a sensor tag ST of a seventh embodiment. Fig. Figure 24 shows an arrangement (part 2) of the sensor tag ST of the seventh embodiment. Fig. Figure 25 shows the shape and dimensions of the sensor tag ST of the seventh embodiment. Fig. Figure 26 shows the operation of the sensor tag ST of the seventh embodiment. Fig. Figure 27 shows the calculation results (oscillation in the X direction) of an nth order coefficient Cn of the seventh embodiment. Fig. Figure 28 shows the calculation results (oscillation in the Y direction) of the coefficient Cn of the seventh embodiment of the nth order. Fig. Figure 29 shows the calculation results (oscillation in the Z direction) of the coefficient Cn of the seventh embodiment. Fig. Figure 30 shows a configuration of a sensor system SS of an eighth embodiment. Fig. Figure 31 shows a configuration of a sensor system SS of a ninth embodiment. DESCRIPTION OF THE EXAMPLES OF EXECUTION

[0010] Exemplary embodiments of a sensor tag, a method for reading a sensor tag, and a sensor system that uses a sensor tag according to the present disclosure are described.

[0011] To facilitate description and understanding, the names of multiple components are referred to below together with a reference symbol. For example, a reference symbol "11" can refer to the two designations "conductor 11a" and "conductor 11b". First embodiment.<Erstes Ausführungsbeispiel>

[0012] A sensor tag of a first embodiment is described. <Konfiguration des ersten Ausführungsbeispiels>

[0013] Fig. Figure 1 shows a configuration of a sensor tag ST of the first embodiment.

[0014] As in Fig. As shown in Figure 1, the sensor tag ST of the first embodiment comprises a plurality of conductors 11, i.e. a conductor 11a and a conductor 11b, and a detection unit 12.

[0015] The “plurality of ladders 11” corresponds to a “plurality of ladders”, the detection unit 12 corresponds to a “detection unit”, and a resonance element 13 corresponds to a “resonance element”.

[0016] Conductor 11a and conductor 11b are elements that form the resonant element 13. Conductor 11a and conductor 11b are located close to each other, so close that they can be electromagnetically coupled.

[0017] The detection unit 12 is arranged between conductor 11a and conductor 11b. In the detection unit 12, a physical property changes with a change in a physical quantity BR (not shown) of an object TB (which, for example, is in a Fig. 30 depicted monitoring target KTB and one in Fig. 31 corresponds to the identification target STB shown), which is to be recorded by the recording unit 12, and for example a form of the recording unit 12 changes. <Funktionsweise des ersten Ausführungsbeispiels>

[0018] Fig. 2A and Fig. Figure 2B illustrates the functionality (part 1) of the sensor tag ST of the first embodiment.

[0019] Fig. 3A and Fig. Figure 3B shows a function (part 2) of the sensor tag ST of the first embodiment.

[0020] Fig. Figure 4 illustrates the functionality (part 3) of the sensor tag ST of the first embodiment.

[0021] If the physical quantity BR of the object TB to be detected by the detection unit 12 changes, the shape of the detection unit 12 in the sensor tag ST changes. A combination of the type of physical quantity BR of the object TB and the type of detection unit 12 is, for example, as follows. (1) The physical quantity BR of the object TB is a displacement, a mechanical vibration, a pressure or the like, and the sensing unit 12 is a spring, a rubber or the like. (2) The physical quantity BR of the object TB is the temperature or similar, and the detection unit 12 is a thermoplastic resin or similar.

[0022] As described above, if the shape of the detection unit 12 changes, the relative positional relationship between conductor 11a and conductor 11b changes, i.e., the distance between conductor 11a and conductor 11b.

[0023] As described above, if the relative positional relationship between conductor 11a and conductor 11b changes, the frequency characteristic of a reflection coefficient or a transmission coefficient of the resonance element 13 changes.

[0024] The “reflection coefficient” and the “transmission coefficient” represent the amount of reflection or transmission of an electromagnetic wave and the amount of phase change at that time.

[0025] If the change in the frequency characteristic of the reflection coefficient or the transmission coefficient of the resonance element 13, caused by the change in the physical quantity BR of the object TB, is to be observed, a reading device YS (e.g. in Fig. 23) the sensor tag ST with an electromagnetic wave (corresponding, for example, to a transmission wave SH, which is in Fig. 23 shown transmitting wave SH) and receives a reflected wave or a transmitted wave (which, for example, is a wave in Fig. 23 shown reflected wave HH corresponds) with a frequency characteristic that changes due to the change in the physical quantity BR of the object TB from the sensor tag ST, whereby the frequency characteristic of the reflected wave or the transmitted wave is observed.

[0026] Based on the observed frequency characteristics of the reflected wave HH and the like, it is possible, by referring to the correspondence relationship (shown in Fig. 2C) between the frequency characteristics of the reflected wave HH and the like and the state of the detection unit 12, which was calculated in advance or detected in advance by an experiment, to estimate the state of the detection unit 12, i.e. the expansion / contraction state (represented in Fig. 2A and Fig. 2B), which is a change of form.

[0027] Furthermore, the physical size of the object TB can be determined from the correspondence relationship (represented in Fig. 3A and Fig. 3B) between the state of the detection unit 12 and the physical quantity BR of the object TB. For example, if the length of the detection unit 12, i.e., the distance between conductor 11a and conductor 11b, is Z1 (mm), it can be estimated that the physical quantity BR of the object TB is Z1 (mm), and if the distance between conductor 11a and conductor 11b is Z2 (mm), it can be estimated that the physical quantity of the object TB is Z2 (mm).

[0028] Instead of the two correspondence relationships mentioned above (shown in Fig. 2A to 2C and Fig. 3A and Fig. 3B) can also be a correspondence relationship (represented in Fig. 4) The frequency characteristics of the reflected wave HH and the like, and the physical quantity BR of the object TB, can be used. For example, a physical quantity BR1 of the object TB and a physical quantity BR2 of the object TB can be distinguished. <Auswirkungen des ersten Ausführungsbeispiels>

[0029] If the physical quantity BR of object TB changes in the sensor tag ST of the first embodiment, as described above, the shape of the sensor tag ST, which is an example of the physical properties of the sensing unit 12, changes, thereby altering the relative position between conductor 11a and conductor 11b. Furthermore, the frequency characteristics of the reflected wave HH and the like change due to the reflection or similar action of the sensor tag ST, since the reflection coefficient or transmission coefficient of the resonant element 13 changes as a result of the change in the relative position between conductor 11a and conductor 11b. Consequently, the physical quantity BR of object TB can be estimated by observing the frequency characteristics described above.

[0030] With the sensor tag ST of the first embodiment, which operates as described above, it is possible to detect the physical quantity BR of the object TB without needing electrical properties (conductivity or dielectric constant) that are required for conventional detection units. Second embodiment.<Zweites Ausführungsbeispiel>

[0031] A sensor tag of a second embodiment is described.

[0032] The sensor tag ST of the second embodiment detects the displacement or vibration of the object TB as the physical quantity BR of the object TB. <Konfiguration des zweiten Ausführungsbeispiels>

[0033] Fig. Figure 5 shows a configuration (part 1) of the sensor tag ST of the second embodiment.

[0034] Fig. Figure 6 shows a configuration (part 2) of the sensor tag ST of the second embodiment.

[0035] Fig. Figure 7 shows a configuration (part 3) of the sensor tag ST of the second embodiment.

[0036] As in Fig. As shown in Figure 5, the sensor tag ST of the second embodiment has a configuration that is essentially the same as the configuration of the sensor tag ST of the first embodiment (shown in Figure 5). Fig. 1) corresponds.

[0037] On the other hand, the sensor tag ST of the second embodiment differs from the sensor tag ST of the first embodiment in that the detection unit 22 is a spring (made of any material), as shown in Fig. 5 shown.

[0038] The sensor tag ST of the second embodiment comprises a substrate 24a and a substrate 24b, as shown in Fig. Figure 5 shows that substrate 24a carries a conductor 21a, and substrate 24b carries a conductor 21b. The dimensions of conductor 21a and conductor 21b are shown, for example, in Fig. 6 shown.

[0039] As in Fig. As shown in Figure 5, the conductor 21a and the substrate 24a form an upper layer 25 of the sensor tag ST, and similarly, the conductor 21b and the substrate 24b form a lower layer 26 of the sensor tag ST.

[0040] As in Fig. As shown in Figure 7, the upper layer 25 is attached to the underside of the object TB1 to be detected, while the lower layer 26 is attached to the top of the object TB2 to be detected. In particular, the upper layer 25 and the lower layer 26 are provided between two separate components that form a structure (bridge or similar), or they are provided between two separate components that form an electronic device. <Funktionsweise des zweiten Ausführungsbeispiels>

[0041] The following assumes that the position of object TB1 (in Fig. 7 shown) is fixed, while the position of object TB2 (in Fig. 7 shown) is moved.

[0042] Fig. Figures 8A to 8C are each a schematic representation showing a displacement and displacement amount of the sensor tag ST of the second embodiment.

[0043] Here, a "reference state" is defined as a state in which the upper layer 25 and the lower layer 26 completely overlap in the direction of the Z-axis, and a state in which the position of the lower layer 26 in the Z-direction is a specific position ( Fig. Figure 8C shows the “lower layer 26 (before the displacement)”. The displacement values ​​dx, dy, and dz (in mm units) are defined as displacement values ​​relative to the “reference state”, as in the Fig. 8A to 8C are shown.

[0044] When the position of object TB2 is moved, the shape of the detection unit 22 changes, the relative position between conductor 21a and conductor 21b changes, and the frequency characteristic of the reflection coefficient or the transmission coefficient of a resonance element 23 changes as in the first embodiment.

[0045] Fig. Figure 9 shows the frequency characteristic (part 1) of the reflection value or magnitude of the second embodiment.

[0046] Fig. Figure 10 shows the frequency characteristic (part 2) of the reflection value of the second embodiment.

[0047] Fig. Figure 11 shows the frequency characteristic (part 3) of the reflection value of the second embodiment.

[0048] The in the Fig. 9, Fig. 10 to Fig. The 11 frequency characteristics of the reflection value or magnitude shown indicate the magnitude of the reflection coefficient of the sensor tag ST with respect to an electromagnetic wave, more precisely an X-polarized wave (polarized wave oscillating in the X direction), when the object TB2 is moved in one of the three directions X, Y and Z.

[0049] The in the Fig. 9, Fig. 10 to Fig. The 11 depicted frequency characteristics of the reflection value are, for example, obtained by a two-dimensional arrangement of a large number of sensor tags ST (shown in Fig. 1) calculated at intervals of 25 mm on an XY plane to increase the reflection value or magnitude to be obtained.

[0050] As in the Fig. 9, Fig. 10 to Fig. As shown in Figure 11, the frequency characteristic of the reflection value changes when object TB2 is moved in one of the directions X, Y, and Z. Conversely, the frequency characteristic of the reflection value differs depending on in which X, Y, and Z direction object TB2 is moved and whether the amount of displacement is large or small.

[0051] As in the first embodiment, the reading device YS irradiates the sensor tag ST with the transmitting wave SH and receives the wave HH or similar reflected by the sensor tag ST, thereby observing the frequency characteristic of the reflected wave HH or similar of the resonance element 23.

[0052] In an essentially similar manner to the first embodiment, it is possible, on the basis of the observed frequency characteristics of the reflected wave HH and the like, to estimate the state of the detection unit 22 and furthermore to estimate the displacement direction and displacement magnitude of the object TB2 by referring to the previously calculated or previously experimentally obtained correspondence relationship between the frequency characteristics of the reflected wave HH and the like and the state of the detection unit 22, based on the observed frequency characteristics of the reflected wave HH and the like and the state of the detection unit 22. <Auswirkungen des zweiten Ausführungsbeispiels>

[0053] As described above, with the sensor tag ST of the second embodiment, the direction and magnitude of displacement of the object TB2 can be detected even if the conductivity or the dielectric constant of the detection unit 22 does not change in response to the change of the object TB2. Third example.<Drittes Ausführungsbeispiel>

[0054] A sensor tag of a third embodiment is described.

[0055] In the sensor tag ST of the third embodiment, a circuit constant of an electrical circuit DK (shown in) changes in a detection unit 32. Fig. 13). <Konfiguration des dritten Ausführungsbeispiels>

[0056] Fig. Figure 12 shows a configuration of the sensor tag ST of the third embodiment.

[0057] Fig. Figure 13 shows the electrical circuit DK of the detection unit 32 of the third embodiment.

[0058] As in Fig. As shown in Figure 12, the sensor tag ST of the third embodiment has a configuration that essentially corresponds to the configuration of the sensor tag ST of the first embodiment (shown in Figure 12). Fig. 1).

[0059] In contrast to the sensor tag ST of the first embodiment, a circuit constant of the electrical circuit DK (shown in) changes in the detection unit 32 of the third embodiment's sensor tag ST. Fig. 13) of the detection unit 32 with a change in the physical quantity BR of the object TB. <Funktionsweise des dritten Ausführungsbeispiels>

[0060] If the physical quantity BR of the object TB changes, the circuit constant of the electrical circuit DK of the detection unit 32 changes, as shown in Fig. As shown in Figure 13, for example the size of a resistor TE, an inductor IN or a capacitor CA, which form the electrical circuit DK, which corresponds to a varactor diode that is an active element, changes.

[0061] If the physical quantity BR of the object TB changes, in other words, if the value of the reverse bias applied to the varactor diode changes, then, for example, the value of the capacitor CA of the electrical circuit DK will change due to the property of the varactor diode.

[0062] The combination of the physical quantity BR of the object TB and the detection unit 32 is, for example, as follows. (1) The physical quantity BR of the object TB is a voltage, an electric field or the like, and the detection unit 32 is a diode or the like. (2) The physical quantity BR of the object TB is a magnetic field or similar, and the detection unit 32 is a magnetic sensor or similar. (3) The physical quantity of the object TB is light or the like, and the detection unit 32 is a CdS sensor or the like. (4) The object TB is the temperature or the like, and the detection unit 32 is a thermistor or the like. (5) The object TB is moisture or the like, and the detection unit 32 is a moisture sensor or the like. (6) The object TB is a gas or the like, and the detection unit 32 is a gas sensor or the like.

[0063] If the circuit constant DK of the electrical circuit of the detection unit 32 changes, the electrical connection state (the situation of how a conductor 31a and a conductor 31b are electrically connected) changes, and the frequency characteristic of the reflection coefficient or the transmission coefficient of a resonance element 33 changes.

[0064] As in the first embodiment, the reading device YS irradiates the sensor tag ST with the transmitting wave SH and receives the reflected wave HH or similar from the sensor tag ST, thereby observing the frequency characteristic of the reflected wave HH and similar of the resonance element 33.

[0065] In an essentially similar manner to the first embodiment, it is possible, on the basis of the observed frequency characteristics of the reflected wave HH and the like, to estimate the state of the detection unit 32 and furthermore to estimate the physical quantity BR of the object TB by referring to the previously calculated or previously experimentally obtained correspondence relationship between the frequency characteristics of the reflected wave HH and the like and the state of the detection unit 32. <Auswirkungen des dritten Ausführungsbeispiels>

[0066] As described above, with the sensor tag ST of the third embodiment, the physical quantity BR of the object TB can also be estimated if the conductivity or the dielectric constant of the detection unit 32 does not change in response to the change of the object TB. Fourth example.<Viertes Ausführungsbeispiel>

[0067] A sensor tag of a fourth embodiment is described.

[0068] The sensor tag ST of the fourth embodiment detects an electric field that represents the physical quantity BR of the object TB. <Konfiguration des vierten Ausführungsbeispiels>

[0069] Fig. Figure 14 shows a configuration (part 1) of the fourth embodiment.

[0070] Fig. Figure 15 shows a configuration (part 2) of the fourth embodiment.

[0071] As in Fig. As shown in Figure 14, the sensor tag ST of the fourth embodiment has a configuration that is essentially the same as the configuration of the sensor tag ST of the first embodiment (shown in Figure 14). Fig. 1) corresponds.

[0072] In contrast to the sensor tag ST of the first embodiment, the sensing unit 42 in the fourth embodiment is a varactor diode. The sensor tag ST of the fourth embodiment also includes a substrate 44. The substrate 44 carries a conductor 41a and a conductor 41b. The dimensions of conductor 41a and conductor 41b are given, for example, in Fig. 15 shown. <Funktionsweise des vierten Ausführungsbeispiels>

[0073] Fig. Figure 16 shows the frequency characteristic of the reflection value of the fourth embodiment.

[0074] The following assumes that the sensor tag ST is located near an electromagnetic noise source on the electronic circuit, for example an IC chip.

[0075] The electromagnetic noise source described above emits an electromagnetic wave. An electric field is generated between conductor 41a and conductor 41b as a result of the electromagnetic wave, and consequently, a voltage is generated between conductor 41a and conductor 41b. If the direction of the generated voltage is in the same direction as the reverse bias of the varactor diode of the detection unit 42, the circuit constant of the detection unit 42, in particular the capacitance of the capacitor, changes depending on the magnitude of the voltage.

[0076] When the capacitance of the capacitor changes, the electrical connection state of conductor 41a and conductor 41b changes, and as a result, the frequency characteristics of the reflected wave HH and the like of the sensor tag ST change.

[0077] Fig. 16 will be determined using a similar procedure as in the Fig. 9, Fig. 10 to Fig. 11 of the second embodiment is calculated. As in Fig. As shown in Figure 16, the frequency characteristic of the reflection value or magnitude changes when the value of the blocking bias is changed to 0 V, 0.1 V and 0.2 V.

[0078] As in the first embodiment, the reading device YS irradiates the sensor tag ST with the transmitting wave SH and receives the wave HH or similar reflected by the sensor tag ST, thereby observing the frequency characteristic of the reflected wave HH or similar of a resonance element 43.

[0079] In an essentially similar manner to the first embodiment, it is possible, on the basis of the observed frequency characteristics of the reflected wave HH and the like, to estimate the state of the detection unit 22 and furthermore to estimate the blocking bias applied to the detection unit 42, i.e., to estimate the magnitude of the electric field of the object TB, based on the observed frequency characteristics of the reflected wave HH and the like and by reference to the correspondence relationship calculated in advance or obtained in advance by experiment between the frequency characteristics of the reflected wave HH and the like and the state of the detection unit 22. <Auswirkungen des vierten Ausführungsbeispiels>

[0080] As described above, with the sensor tag ST of the fourth embodiment, the electric field of the object TB can be detected even if the conductivity or the dielectric constant of the detection unit 42 does not change in response to the change in the electric field of the object TB. <modifikation>

[0081] Instead of the electromagnetic noise described above, which propagates through space (i.e., so-called radiation noise), the electromagnetic noise that propagates through the circuitry of the electronic circuit (i.e., so-called line noise) can be detected. In a case where line noise is to be detected, two points where a voltage due to electromagnetic noise appears on the line are electrically connected in a one-to-one correspondence with conductor 41a and conductor 41b; that is, the circuit is configured such that a voltage due to electromagnetic noise appears between conductor 41a and conductor 41b. Thus, the line noise can be detected as described above. Fifth example.<Fünftes Ausführungsbeispiel>

[0082] A fifth embodiment describes a sensor tag.

[0083] In contrast to the first to fourth embodiments, in which the physical quantity BR of the object TB is directly detected, the sensor tag ST of the fifth embodiment detects the physical quantity BR of the object TB indirectly by combining a plurality of detection units. <Konfiguration des fünften Ausführungsbeispiels>

[0084] Fig. Figure 17 shows a configuration of a sensor tag ST of the fifth embodiment.

[0085] As in Fig. As shown in Figure 17, the sensor tag ST of the fifth embodiment has a configuration that is essentially the same as the configuration of the sensor tag ST of the first embodiment (shown in Figure 17). Fig. 1) corresponds.

[0086] The sensor tag ST of the fifth embodiment comprises, in addition to a main detection unit 52, a secondary detection unit 52a and a secondary detection unit 52b (this corresponds to the detection unit 42 of the in Fig. (Figure 14, fourth embodiment). The secondary detection unit 52a and the secondary detection unit 52b are, for example, vibration sensors with piezoelectric elements. The secondary detection unit 52a and the secondary detection unit 52b are arranged parallel to the main detection unit 52 between a conductor 51a and a conductor 51b. <Funktionsweise des fünften Ausführungsbeispiels>

[0087] If the physical quantity BR of object TB changes in the sensor tag ST of the fifth embodiment, the physical properties of the secondary detection unit 52a and the secondary detection unit 52b also change. If the physical properties of the secondary detection unit 52a and the secondary detection unit 52b change, the physical properties of the main detection unit 52 also change.

[0088] In contrast to the detection units 12 to 42 of the first to fourth embodiments, which directly detect the physical quantity BR of the object TB, the main detection unit 52 detects the physical quantity BR indirectly via the secondary detection unit 52a and the secondary detection unit 52b.

[0089] When object TB vibrates, the auxiliary detection unit 52a and the auxiliary detection unit 52b generate a voltage. This creates a voltage between conductor 51a and conductor 51b.

[0090] If the direction of the voltage between conductor 51a and conductor 51b follows the direction of the reverse bias of the varactor diode of the main sensing unit 52, the circuit constant of the main sensing unit 52, in particular the size of the capacitor, changes depending on the size of the voltage.

[0091] Then, as with the sensor tag ST of the fourth embodiment, the magnitude of the blocking bias applied to the main detection unit 52 can be estimated by observing the frequency characteristic of the reflection value or magnitude, and furthermore, the oscillation or vibration of the object TB can be estimated from the magnitude of the blocking bias. <Auswirkungen des fünften Ausführungsbeispiels>

[0092] As described above, the vibration of the object TB can be detected in the sensor tag ST of the fifth embodiment even if the conductivity or the dielectric constant of the main detection unit 52, the secondary detection unit 52a and the secondary detection unit 52b does not change in response to the change in the physical quantity BR of the object TB. Sixth embodiment.<Sechstes Ausführungsbeispiel>

[0093] A sixth embodiment describes a sensor tag.

[0094] For the sensor tag ST of the sixth embodiment, a chipless RFID technology is used, and in particular, identification information is added to the sensor tag ST of the first to fifth embodiments. <Konfiguration des sechsten Ausführungsbeispiels>

[0095] The Fig. Figures 18A to 18C each show a configuration of the ST sensor tag of the sixth embodiment.

[0096] The sensor tag ST of the sixth embodiment has a configuration that is essentially similar to the configuration of the sensor tag ST of the second embodiment (shown in Fig. 5).

[0097] As in the Fig. As shown in Figures 18A to 18C, the upper layer 25 of the sensor tag ST of the sixth embodiment, in contrast to the sensor tag ST of the second embodiment, has a conductor pattern with a single or double loop structure corresponding to the identification information “01”, “10”, and “11”. As shown in the Fig. As shown in 18A to 18C, the presence or absence of the inner line pattern corresponds to whether the lower bit of the identification information is 1 or 0, and similarly, the presence or absence of the outer line pattern corresponds to whether the upper bit of the identification information is 1 or 0. <Funktionsweise des sechsten Ausführungsbeispiels>

[0098] Fig. Figure 19 shows the frequency characteristic (without shift) of the reflection value of the sixth embodiment.

[0099] Fig. Figure 20 shows the frequency characteristic (shift in the X direction) of the reflection value or magnitude of the sixth embodiment.

[0100] Fig. Figure 21 shows the frequency characteristic (shift in the Y direction) of the reflection value or magnitude of the sixth embodiment.

[0101] Fig. Figure 22 shows the frequency characteristic (shift in the Z direction) of the reflection value or magnitude of the sixth embodiment.

[0102] The sensor tag ST of the sixth embodiment performs a function that is essentially the same as (in the Fig. 8, Fig. 9, Fig. 10 to Fig. The process of the sensor tag ST of the second embodiment is shown in section 11.

[0103] Fig. 19, Fig. 20, Fig. 21 to Fig. 22 will be determined using a similar procedure as in Fig. 9, Fig. 10 to Fig. 11 of the second embodiment is calculated. The ones in the Fig. The displacement amounts dx, dy and dz shown in 8A to 8C of the second embodiment are 2 mm, 2 mm and -2 mm respectively.

[0104] Since the structure of conductor 21a (shown in Fig. 5) of the upper layer 25, i.e., the presence or absence of the inner conduction pattern and the presence or absence of the outer conduction pattern (shown in Fig. 18A to 18C) for each of the identification information “01”, “10” and “11” are different, the frequency characteristics of the reflection coefficient or the transmission coefficient of the resonance element 23 (shown in Fig. 5) different for each of the identification information “01”, “10” and “11”, even if the displacement amount of the object TB is the same.

[0105] By using the ST sensor tag (shown in Fig. 18A) with the identification information “01”, of the sensor tag ST (shown in Fig. 18B) with the identification information “10” and the sensor tag ST (shown in Fig. 18C) with the identification information “11”, different frequency characteristics are obtained depending on the magnitude of the displacement of object TB. This makes it possible to record the displacement of object TB and, based on the reception conditions of the three sensor tags ST, to determine whether the identification information of sensor tag ST is “01”, “10” or “11”. <Auswirkungen des sechsten Ausführungsbeispiels>

[0106] As described above, with the sensor tag ST of the sixth embodiment, even if the conductivity or the dielectric constant of the detection unit 22 does not change according to the displacement amount of the object TB, the displacement amount of the object TB can be detected and the identification information “01”, “10” and “11” can be read. Seventh embodiment.<Siebtes Ausführungsbeispiel>

[0107] A seventh embodiment describes a sensor tag.

[0108] The sensor tag ST of the seventh embodiment serves in particular to detect a change in the physical quantity BR with temporal periodicity of the object TB and to read the period and amplitude of the change using the sensor tag ST of the first to sixth embodiments. <Konfiguration des siebten Ausführungsbeispiels>

[0109] Fig. Figure 23 shows an arrangement (part 1) of the sensor tag ST of the seventh embodiment.

[0110] Fig. Figure 24 shows an arrangement (part 2) of the sensor tag ST of the seventh embodiment.

[0111] Fig. Figure 25 shows the shape and dimensions of the sensor tag ST of the seventh embodiment.

[0112] Fig. Figure 26 shows the operation of the sensor tag ST of the seventh embodiment.

[0113] As in Fig. As shown in Figure 24, the sensor tag ST of the seventh embodiment has a configuration that is essentially the same as the configuration of the sensor tag ST of the second embodiment (shown in Figure 24). Fig. 5) corresponds.

[0114] On the other hand, in the case of the sensor tag ST of the seventh embodiment, in contrast to the sensor tag ST of the second embodiment, as shown in Fig. Figure 24 shows a printed circuit board DB arranged on the back side of the lower layer 26 of the sensor tag ST with spacers SP arranged between them.

[0115] The upper layer 25 and the lower layer 26 of the sensor tag ST have the in Fig. 25 shapes and dimensions shown.

[0116] As in Fig. As shown in Figure 23, the reader YS sends the transmitting wave SH to the sensor tag ST, receives the reflected wave HH from the sensor tag ST and calculates a spectrum of the received reflected wave HH. <Funktionsweise des siebten Ausführungsbeispiels>

[0117] In the seventh embodiment, as in the second embodiment, it is assumed that the vibration or oscillation of the object TB is detected. <Grundlegendes Arbeitsprinzip>

[0118] The ST sensor tag of the seventh embodiment operates as follows.

[0119] If the physical size BR of the object TB changes, the shape of the detection unit 22 changes (in Fig. 5 shown), the relative position between conductor 21a and conductor 21b (in Fig. 5 shown), and the frequency characteristic of the reflection coefficient or the transmission coefficient of the resonance element 23 changes.

[0120] The reader YS observes a spectrum of the reflected wave HH or similar, which is reflected by the sensor tag ST from the transmitted wave SH sent by the reader YS. The reader YS determines the frequency of the periodic change from the frequency intervals of the spectrum, and conversely, the amplitude of the periodic change from the pattern of the spectrum. <Einzelheiten zur Arbeitsweise>

[0121] Specifically, the ST sensor tag of the seventh embodiment works as follows.

[0122] The reflection value of the sensor tag ST is 0 dB, since the circuit board DB is present (as shown in Fig. 24 shown).

[0123] A reflection phase in the sensor tag ST is in Fig. 26 shown. Fig. 26 will be determined according to a similar procedure as in the Fig. 9, Fig. 10 to Fig. Calculated in section 11 of the second embodiment.

[0124] If the detection unit 22 detects the change in the physical quantity BR with temporal periodicity, the reflection magnitude or value and the reflection phase of the resonance element 23, in other words the reflection coefficient, have a temporal periodicity.

[0125] Therefore, a reflection coefficient R is expressed by the following Fourier series. R(t)=∑n=−∞∞Cnej2πnfvt

[0126] Cn is an nth-order coefficient, fv is a rate of change of the physical quantity BR of object TB, and t is time. The coefficient Cn is calculated as follows. Cn=1Tv∫0TvR(t)e−j2πnfvtdt

[0127] Tv is a period of change of the physical quantity BR of the object TB and is the reciprocal of fv. From the equation above, an electric field Er of the reflected wave HH can be expressed as follows. Er(t)=∑n=−∞∞Cnej2πnfvtEi(t)=A∑i=−∞∞Cnej2π(fi+fv)t

[0128] Ei is an electric field of the transmitting wave SH, which is emitted by the reader YS, and A and fi are the amplitude and frequency of Ei, respectively. As described above, the reflected wave HH has a harmonic component fi + nfv in addition to fi when the reader YS transmits the transmitting wave SH with a single frequency fi.

[0129] The reader YS emits the transmitting wave SH at a single frequency. If the physical quantity BR of the object TB varies periodically over time, the harmonic component calculated by the equation above appears in the spectrum of the reflected wave HH.

[0130] Fig. Figure 27 shows the calculation results (oscillation in the X direction) of an nth order coefficient Cn of the seventh embodiment.

[0131] Fig. Figure 28 shows the calculation results (oscillation or vibration in the Y direction) of a coefficient Cn nth order of the seventh embodiment.

[0132] Fig. Figure 29 shows the calculation results (oscillation in the Z direction) of a coefficient Cn of the nth order of the seventh embodiment.

[0133] Ax, Ay and Az are amplitudes (in mm) of the vibration of object TB.

[0134] In the Fig. 27, Fig. 28 to Fig. 29 It is assumed that X-polarized waves are incident.

[0135] Cn represents the amplitude of a frequency component of an nth harmonic, so that the spectrum of the reflected wave HH also exhibits a similar pattern to that in the Fig. 27, Fig. 28 to Fig. 29 shown.

[0136] The spectrum described above is a discrete spectrum with a component at the frequency of (fi + nfv). The frequency intervals of the spectrum are determined by fv, i.e., the frequency of the periodic change.

[0137] The pattern of the spectrum is determined by the amplitude of the periodic change. Therefore, the frequency and amplitude of the periodic change can be estimated based on the correspondence relationship between the pre-calculated or experimentally determined spectrum of the reflected wave HH and the spectrum of the observed reflected wave HH. <Auswirkungen des siebten Ausführungsbeispiels>

[0138] As described above, in the seventh embodiment, for example, the frequency and amplitude of change of the physical quantity BR of object TB can be read without obtaining the spectrum of the reflected wave by sampling the frequency of the electromagnetic wave emitted by the reading device YS, i.e., by setting the frequency of the transmitted wave SH emitted by the reading device YS to a single frequency, observing the harmonic component that appears when the physical quantity BR of object TB varies over time, and analyzing the pattern of the observed harmonic component. Eighth example.<Achtes Ausführungsbeispiel>

[0139] An eighth embodiment describes a sensor-tag system.

[0140] A sensor system SS of the eighth embodiment uses the sensor tag ST of the first to seventh embodiments to detect a failure and anomaly of electrical devices, a structure and the like, which are the monitoring target KTB, with the states of the electrical devices, the structure and the like being monitored. <Konfiguration des achten Ausführungsbeispiels>

[0141] Fig. Figure 30 shows a configuration of the sensor system SS of the eighth embodiment.

[0142] As in Fig. As shown in Figure 30, the sensor system SS of the eighth embodiment comprises the sensor tags ST1 to ST3 (corresponding to the sensor tag ST of the first to seventh embodiments). As shown in Fig. Figure 30 shows that the sensor tags ST1 to ST3 are arranged on surfaces of electrical devices, structures and the like, which represent the monitoring target KTB. <Funktionsweise des achten Ausführungsbeispiels>

[0143] The YS reading device detects a change (e.g., oscillation or vibration of a bridge, oscillation or vibration of a building, and electromagnetic noise in a building and near an electronic device) of the physical quantity BR of the monitoring target KTB via the sensor tags ST1 to ST3 using the detection method described in the first to seventh embodiments.

[0144] The reading device YS compares the detected physical quantity BR of the monitoring target KTB, for example, with a predefined threshold value to determine whether an anomaly has occurred in the monitoring target KTB or not. <Auswirkungen des achten Ausführungsbeispiels>

[0145] As described above, in the sensor system SS of the eighth embodiment it is possible to monitor the state of the monitoring target KTB, such as an electrical device and a structure, using the sensor tag ST of the first to seventh embodiments, i.e. using the sensor tag ST, which achieves the effects of the first to seventh embodiments. Ninth embodiment.<Neuntes Ausführungsbeispiel>

[0146] A sensor system of the ninth embodiment is described.

[0147] The SS sensor system of the ninth embodiment uses the ST sensor tag of the first through seventh embodiments to identify an individual, such as an electronic device or a robot. For identification, the identification information described in the sixth embodiment (shown in Fig. 18A to 18C).

[0148] In addition to the identification mentioned above, the sensor system SS of the ninth embodiment identifies a person using so-called artifact metrics, more precisely using characteristics of the person in whom the sensor tag ST is located. <Konfiguration des neunten Ausführungsbeispiels>

[0149] Fig. Figure 31 shows a configuration of the sensor system SS of the ninth embodiment.

[0150] As in Fig. As shown in Figure 31, the sensor system SS of the ninth embodiment comprises a sensor tag ST (corresponding to the sensor tag ST of the first to seventh embodiments). <Funktionsweise des neunten Ausführungsbeispiels>

[0151] The reading device YS detects a change in the physical quantity BR (e.g. vibrations and electromagnetic noise of an unmanned aircraft and electromagnetic noise of an electronic device) of the identification target STB (e.g. of an unmanned aircraft) via the sensor tag ST using the detection method described in the first to seventh embodiments.

[0152] The reader YS compares the captured physical quantity BR of the identification target STB, for example, with a threshold value determined by artifact metrics, such as pre-captured information that specifies a relationship between the type of person, the identification information, and the physical quantity BR, and thus determines whether the identification target STB is correct or incorrect, i.e., whether the identification target STB is genuine or not. <Auswirkungen des neunten Ausführungsbeispiels>

[0153] As described above, in the sensor system SS of the ninth embodiment it is possible to identify an individual such as an electronic device and a robot using the sensor tag ST of the first to seventh embodiments, i.e. using the sensor tag ST that achieves the effects of the first to seventh embodiments.

[0154] The embodiments described above can be combined without deviating from the core of the present disclosure, and components in each embodiment can be appropriately eliminated or modified, or other components can be added. INDUSTRIAL APPLICABILITY

[0155] A sensor tag according to the present disclosure can be used to detect a physical size of an object, even if the conductivity or dielectric constant of a detection unit does not change, although the physical size of the object changes. REFERENCE MARK LIST

[0156] 11a: conductor, 11b: conductor, 12: detection unit, 13: resonance element, 21a: conductor, 21b: conductor, 22: detection unit, 23: resonance element, 24a: substrate, 24b: substrate, 25: upper layer, 26: lower layer, 31a: conductor, 31b: conductor, 32: detection unit, 33: resonance element, 41a: conductor, 41b: conductor, 42: detection unit, 43: resonance element, 44: substrate, 51a: conductor, 51b: conductor, 52: main detection unit, 52a: secondary detection unit, 52b: secondary detection unit, BR: physical quantity, BR1: physical quantity, BR2: physical quantity, CA: capacitor, Cn: coefficient, DK: electrical circuit, dx: displacement magnitude, dy: displacement magnitude dz: displacement magnitude, Er: electric field, fi: single frequency, HH: reflected wave, IN: inductor, KTB: monitoring target, R: reflection coefficient, SH: transmission wave, SP: spacer, SS: sensor system, ST: sensor tag, ST1: sensor tag, ST3: sensor tag, STB: identification target, TB: object, TB1: object, TB2: objectTE: Resistance, YS: Reader,< / modifikation>

Claims

Sensor tag (ST), comprising: a plurality of conductors (11) arranged close together and forming a resonance element (13); and a sensing unit (12) arranged between the plurality of conductors and having a physical property which changes as a result of a change in a physical quantity (BR) of an object (TB) to be sensed by the sensing unit. Sensor tag (ST) according to claim 1, wherein the relative positions of the plurality of conductors (11) change depending on a change in the shape of the sensor unit (12). Sensor tag (ST) according to claim 2, wherein the sensor unit (12) is a spring. Sensor tag (ST) according to claim 1, wherein the detection unit (12) comprises an electrical circuit (DK) whose circuit constant changes depending on a change in a physical quantity (BR) of the object (TB). Sensor tag (ST) according to claim 4, wherein the electrical circuit (DK) is an active element. Sensor tag (ST) comprising: a plurality of conductors (11) arranged close together and forming a resonance element (13); and a main sensing unit (52) and a secondary sensing unit (52a, 52b) arranged between the plurality of conductors (11), wherein a physical property of the main sensing unit changes due to a change in a physical property of the secondary sensing unit (52a, 52b) due to a change in a physical quantity (BR) of an object (TB) to be sensed by the main sensing unit and the secondary sensing unit. Sensor tag (ST) according to claim 6, wherein the secondary detection unit (52a, 52b) is able to detect vibrations which are a physical quantity (BR) of the object (TB), and the main detection unit (52) contains an active element whose physical properties change by applying a voltage which is generated as a result of the detection of the vibrations by the secondary detection unit. Sensor tag (ST) according to claim 1, further comprising: at least one wiring pattern (11) for indicating identification information. Sensor tag (ST) according to claim 8, wherein the at least one conductor pattern (11) has the form of a loop. Sensor tag (ST) according to claim 1, wherein a plurality of two-dimensionally arranged elements, each of the plurality of elements comprising the plurality of conductors (11) and the detection unit (12). Method for reading a sensor tag, wherein the method comprises: estimating a period and amplitude of a change in a physical quantity (BR) of the object (TB) due to a change in a reflection characteristic or a transmission characteristic of the sensor tag (ST) according to any one of claims 1 to 6 in response to the reception of a transmission wave with a single frequency. Method for reading a sensor tag according to claim 11, wherein a period and amplitude of the vibration of the object (TB) are estimated. Method for reading a sensor tag according to claim 11, wherein a period and amplitude of the oscillations of electromagnetic noise are estimated. Sensor system (SS), comprising: the sensor tag (ST) according to any one of claims 1 to 10 . Sensor system (SS) according to claim 14, wherein a state of the object (TB) is monitored. Sensor system (SS) according to claim 14, wherein an individual identification of the object (TB) is carried out.

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