Chipless rfid gesture recognition sensor resonant structure model

Abstract

The application discloses a chipless RFID gesture recognition sensor resonant structure model, which comprises a dielectric plate, a rectangular feed microstrip line is arranged on the top surface of the dielectric plate along the transverse direction and close to the upper edge, a first resonant unit, a second resonant unit, a third resonant unit and a fourth resonant unit are arranged on the top surface of the dielectric plate from left to right along the transverse direction, and the first resonant unit, the second resonant unit, the third resonant unit and the fourth resonant unit are located below the rectangular feed microstrip line; and a rectangular ground is arranged on the bottom surface of the dielectric plate. Different lengths of the resonant units are arranged, different intervals between the resonant units for recognizing different joints of the same finger and the feed microstrip line are arranged, and intervals between adjacent resonant units for recognizing the same finger and intervals between adjacent resonant units for recognizing different fingers are set as different values, so that independent recognition of different finger joint postures is realized. The resonant structure model is small in size, convenient to process and integrated with wireless equipment.

Description

Technical Field

[0001] This invention belongs to the field of gesture recognition device technology, specifically relating to a resonant structure model of a chipless RFID gesture recognition sensor. Background Technology

[0002] Gesture recognition technology allows users to control or interact with devices using simple gestures, enabling computers to understand human behavior and playing a crucial role in certain applications.

[0003] To date, methods proposed by scholars for gesture recognition can be divided into two main categories: vision-based methods and methods based on traditional sensors. Because vision-based methods are limited by changes in lighting, and methods based on traditional sensors are limited by the physical connection to the computer, methods based on chipless radio frequency identification (RFID) technology have been proposed. RFID can operate in low-visibility scenarios and can perform wireless communication, making it easier to meet market demands. Chipless RFID sensors consist of transceiver antennas and a resonant structure. The resonant structure is its core component, responsible for carrying sensor information, equivalent to the chip in a chip-based RFID tag. In 2015, Taoran Le designed a four-finger resonant structure model containing a microstrip transmission line and four helical resonant units for recognizing whether the entire finger is bent. In 2021, Giuseppina Monti designed a three-finger resonant structure model containing a microstrip transmission line and three stubular resonant units, also for recognizing the posture of the entire finger.

[0004] The drawback of the aforementioned resonant structure models is that they can only achieve simple recognition of the posture of the entire finger, and cannot achieve independent recognition of the posture of each finger joint. In practical gesture recognition applications, recognizing whether a specific joint is bent or not can more accurately identify gestures and thus provide more gesture combinations, which is of great significance. Summary of the Invention

[0005] The purpose of this invention is to provide a resonant structure model for a chipless RFID gesture recognition sensor, which solves the problem in the prior art that the posture of each finger joint cannot be independently recognized.

[0006] The technical solution adopted in this invention is a chipless RFID gesture recognition sensor resonant structure model, including a dielectric substrate. A rectangular feed microstrip line is arranged on the top surface of the dielectric substrate along the horizontal direction and near the upper edge. A first resonant unit, a second resonant unit, a third resonant unit, and a fourth resonant unit are arranged on the top surface of the dielectric substrate from left to right along the horizontal direction. The first resonant unit, the second resonant unit, the third resonant unit, and the fourth resonant unit are located below the rectangular feed microstrip line. A rectangular ground is provided on the bottom surface of the dielectric substrate.

[0007] The invention is further characterized in that,

[0008] The rectangular-fed microstrip line, the first resonant unit, the second resonant unit, the third resonant unit, the fourth resonant unit, and the rectangular ground are all metal patches, and the dielectric substrate is made of cotton material.

[0009] The dielectric substrate has a length of 74.5mm ± 0.1mm, a width of 65mm ± 0.1mm, and a thickness of 1mm ± 0.01mm; the rectangular feed microstrip line has a length of 65mm ± 0.1mm, a width of 3.5mm ± 0.1mm, and a thickness of 0.1mm ± 0.01mm.

[0010] The first resonant unit has a length of 61.5mm ± 0.01mm, a width of 3.5mm ± 0.1mm, and a thickness of 0.1mm ± 0.01mm; the second resonant unit has a length of 52.5mm ± 0.01mm, a width of 3.5mm ± 0.1mm, and a thickness of 0.1mm ± 0.01mm; the third resonant unit has a length of 57mm ± 0.01mm, a width of 3.5mm ± 0.1mm, and a thickness of 0.1mm ± 0.01mm; and the fourth resonant unit has a length of 48mm ± 0.01mm, a width of 3.5mm ± 0.1mm, and a thickness of 0.1mm ± 0.01mm.

[0011] The distance between the first resonant unit and the second resonant unit is 9mm ± 0.1mm; the distance between the second resonant unit and the third resonant unit is 12mm ± 0.1mm; and the distance between the third resonant unit and the fourth resonant unit is 9mm ± 0.1mm.

[0012] The distance between the top of the first resonant unit and the bottom of the rectangular feed microstrip line is 2mm ± 0.01mm; the distance between the top of the second resonant unit and the bottom of the rectangular feed microstrip line is 0.5mm ± 0.01mm; the distance between the top of the third resonant unit and the bottom of the rectangular feed microstrip line is 2mm ± 0.01mm; and the distance between the top of the fourth resonant unit and the bottom of the rectangular feed microstrip line is 0.5mm ± 0.01mm.

[0013] The length and width of the rectangular area are the same as those of the substrate, and the thickness of the rectangular area is 0.1mm ± 0.01mm.

[0014] The beneficial effects of this invention are that, by setting different lengths for each resonant unit, setting different spacings between the resonant units that identify different joints of the same finger and the feed microstrip line, and setting different spacings between adjacent resonant units that identify the same finger and adjacent resonant units that identify different fingers, independent recognition of different finger joint postures is achieved. The resonant structure model is small in size, facilitating fabrication and integration into wireless devices. Attached Figure Description

[0015] Figure 1 This is a front structural schematic diagram of the resonant structure model of the chipless RFID gesture recognition sensor of the present invention;

[0016] Figure 2 This is a schematic diagram of the back structure of the resonant structure model of the chipless RFID gesture recognition sensor of the present invention;

[0017] Figure 3 This is a curve showing the transmission coefficient of the resonant structure model of this invention when only one resonant unit is connected to the feed microstrip line or when they are not connected at all.

[0018] Figure 4 This is a curve showing the transmission coefficient results when two different resonant units of the resonant structure model of this invention are connected to a fed microstrip line;

[0019] Figure 5 This is a graph showing the transmission coefficient results when the three different resonant units of the resonant structure model of this invention are connected or fully connected to the fed microstrip line.

[0020] In the figure, 1. First resonant unit, 2. Second resonant unit, 3. Third resonant unit, 4. Fourth resonant unit, 5. Rectangular feed microstrip line, 6. Dielectric substrate, 7. Rectangular ground. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1

[0023] The chipless RFID gesture recognition sensor resonant structure model of this invention, as shown below. Figure 1 and Figure 2 As shown, the device includes a dielectric substrate 6. A rectangular feed microstrip line 5 is arranged horizontally on the top surface of the dielectric substrate 6 near its upper edge. A first resonant unit 1, a second resonant unit 2, a third resonant unit 3, and a fourth resonant unit 4 are arranged horizontally from left to right on the top surface of the dielectric substrate 6. The first resonant unit 1, the second resonant unit 2, the third resonant unit 3, and the fourth resonant unit 4 are located below the rectangular feed microstrip line 5. A rectangular ground plane 7 of the same size as the dielectric substrate 6 is provided on the bottom surface of the dielectric substrate 6.

[0024] The rectangular feed microstrip line 5, the first resonant unit 1, the second resonant unit 2, the third resonant unit 3, the fourth resonant unit 4, and the rectangular ground 7 are metal patches, and the dielectric substrate 6 is made of glove-like cotton material.

[0025] First, by setting different spacing between the resonant units, the resonant units acting on different fingers are distinguished (the first resonant unit 1 and the second resonant unit 2 act on the same finger, and the third resonant unit 3 and the fourth resonant unit 4 act on the same finger).

[0026] By setting different lengths of the resonant units and different spacings between them and the feed microstrip line 5, the resonant units acting on different joints are distinguished (the first resonant unit 1 and the third resonant unit 3 act on the second joint of the corresponding finger, while the second resonant unit 2 and the fourth resonant unit 4 act on the first joint of the corresponding finger). Finally, only when the finger joint is bent does the spacing between its corresponding resonant unit and the feed microstrip line 5 disappear, achieving a connection between the two. At this time, a corresponding notch will appear in its spectrum. By distinguishing the number and position of the notches, independent identification of different finger joint postures can be achieved.

[0027] The length L1 of the dielectric substrate 6 is 74.5mm ± 0.1mm, the width W1 is 65mm ± 0.1mm, and the thickness is 1mm ± 0.01mm;

[0028] The rectangular feed microstrip line 5 has a length L2 of 65mm ± 0.1mm, a width W2 of 3.5mm ± 0.1mm, and a thickness of 0.1mm ± 0.01mm.

[0029] The length L3 of the first resonant unit 1 is 61.5mm ± 0.01mm, the width W3 is 3.5mm ± 0.1mm, and the thickness is 0.1mm ± 0.01mm;

[0030] The length L4 of the second resonant unit 2 is 52.5mm ± 0.01mm, the width W4 is 3.5mm ± 0.1mm, and the thickness is 0.1mm ± 0.01mm.

[0031] The length L5 of the third resonant unit 3 is 57mm ± 0.01mm, the width W5 is 3.5mm ± 0.1mm, and the thickness is 0.1mm ± 0.01mm;

[0032] The length L6 of the fourth resonant unit 4 is 48mm ± 0.01mm, the width W6 is 3.5mm ± 0.1mm, and the thickness is 0.1mm ± 0.01mm.

[0033] The distance D1 between the first resonant unit 1 and the second resonant unit 2 is 9mm ± 0.1mm;

[0034] The distance D2 between the second resonant unit 2 and the third resonant unit 3 is 12mm ± 0.1mm;

[0035] The distance D3 between the third resonant unit 3 and the fourth resonant unit 4 is 9mm ± 0.1mm.

[0036] The distance G1 between the top of the first resonant unit 1 and the bottom of the rectangular feed microstrip line 5 is 2mm ± 0.01mm;

[0037] The distance G2 between the top of the second resonant unit 2 and the bottom of the rectangular feed microstrip line 5 is 0.5mm ± 0.01mm;

[0038] The distance G3 between the top of the third resonant unit 3 and the bottom of the rectangular feed microstrip line 5 is 2mm ± 0.01mm;

[0039] The distance G4 between the top of the fourth resonant unit 4 and the bottom of the rectangular feed microstrip line 5 is 0.5mm ± 0.01mm.

[0040] The rectangular ground 7 has the same length and width as the dielectric plate 6, and a thickness of 0.1mm ± 0.01mm.

[0041] Example 2

[0042] This invention discloses a chipless RFID gesture recognition sensor resonant structure model, which operates on the four joints of two fingers. When the finger joints are straight, the resonant unit remains disconnected from the rectangular feed microstrip line 5. When the second joint of the first finger is bent, the first resonant unit 1 is compressed, and the gap between it and the rectangular feed microstrip line 5 disappears, achieving connection between the two. When the first joint of the first finger is bent, the second resonant unit 2 is compressed, and the gap between it and the rectangular feed microstrip line 5 disappears, achieving connection between the two. When the second joint of the second finger is bent, the third resonant unit 3 is compressed, and the gap between it and the rectangular feed microstrip line 5 disappears, achieving connection between the two. When the first joint of the second finger is bent, the fourth resonant unit 4 is compressed, and the gap between it and the rectangular feed microstrip line 5 disappears, achieving connection between the two.

[0043] Example 3

[0044] The present invention discloses a chipless RFID gesture recognition sensor resonant structure model, including a dielectric substrate 6 with a dielectric constant of 1.48; a rectangular feed microstrip line 5; a first resonant unit 1; a second resonant unit 2; a third resonant unit 3; a fourth resonant unit 4; and a rectangular ground 7, which is a metal patch.

[0045] The length L1 of the dielectric substrate 6 is 74.5 mm, the width W1 is 65 mm, and the thickness is 1 mm.

[0046] The rectangular feed microstrip line 5 has a length L2 of 65mm, a width W2 of 3.5mm, and a thickness of 0.1mm.

[0047] The length L3 of the first resonant unit 1 is 61.5mm, the width W3 is 3.5mm, and the thickness is 0.1mm;

[0048] The second resonant unit 2 has a length L4 of 52.5 mm, a width W4 of 3.5 mm, and a thickness of 0.1 mm.

[0049] The length L5 of the third resonant unit 3 is 57mm, the width W5 is 3.5mm, and the thickness is 0.1mm;

[0050] The fourth resonant unit 4 has a length L6 of 48mm, a width W6 of 3.5mm, and a thickness of 0.1mm.

[0051] The distance D1 between the first resonant unit 1 and the second resonant unit 2 is 9mm;

[0052] The distance D2 between the second resonant unit 2 and the third resonant unit 3 is 12mm;

[0053] The distance D3 between the third resonant unit 3 and the fourth resonant unit 4 is 9mm;

[0054] The distance G1 between the top of the first resonant unit 1 and the bottom of the rectangular feed microstrip line 5 is 2mm;

[0055] The distance G2 between the top of the second resonant unit 2 and the bottom of the rectangular feed microstrip line 5 is 0.5mm;

[0056] The distance G3 between the top of the third resonant unit 3 and the bottom of the rectangular feed microstrip line 5 is 2mm;

[0057] The distance G4 between the top of the fourth resonant unit 4 and the bottom of the rectangular feed microstrip line 5 is 0.5mm.

[0058] Figure 3 This is a graph showing the transmission coefficient results when only one resonant unit is connected to the rectangular feed microstrip line 5 or when none of them are connected. Curve B0 represents the transmission coefficient result when none of the four resonant units are connected to the rectangular feed microstrip line 5, in which case no notch appears. Curve B1 represents the transmission coefficient result when the first resonant unit 1 is connected to the rectangular feed microstrip line 5, in which case a notch appears at a frequency of 3.11 GHz. Curve B2 represents the transmission coefficient result when the second resonant unit 2 is connected to the rectangular feed microstrip line 5, in which case a notch appears at a frequency of 3.619 GHz. Curve B3 represents the transmission coefficient result when the third resonant unit 3 is connected to the rectangular feed microstrip line 5, in which case a notch appears at a frequency of 3.355 GHz. Curve B4 represents the transmission coefficient result when the fourth resonant unit 4 is connected to the rectangular feed microstrip line 5, in which case a notch appears at a frequency of 3.965 GHz.

[0059] Figure 4This is a graph showing the transmission coefficient results when two different resonant units of the resonant structure model of this invention are connected to the rectangular feed microstrip line 5. Curve B12 shows the transmission coefficient results when both the first resonant unit 1 and the second resonant unit 2 are connected to the rectangular feed microstrip line 5, where notch filters appear at frequencies of 3.11 GHz and 3.619 GHz; curve B13 shows the transmission coefficient results when both the first resonant unit 1 and the third resonant unit 3 are connected to the rectangular feed microstrip line 5, where notch filters appear at frequencies of 3.11 GHz and 3.355 GHz; curve B14 shows the transmission coefficient results when both the first resonant unit 1 and the fourth resonant unit 4 are connected to the rectangular feed microstrip line 5, where notch filters appear at frequencies of 3.11 GHz and 3.965 GHz. Curve B23 shows the transmission coefficient when both the second resonant unit 2 and the third resonant unit 3 are connected to the rectangular feed microstrip line 5, where notch filtering occurs at frequencies of 3.355 GHz and 3.619 GHz; Curve B24 shows the transmission coefficient when both the second resonant unit 2 and the fourth resonant unit 4 are connected to the rectangular feed microstrip line 5, where notch filtering occurs at frequencies of 3.619 GHz and 3.965 GHz; Curve B34 shows the transmission coefficient when both the third resonant unit 3 and the fourth resonant unit 4 are connected to the rectangular feed microstrip line 5, where notch filtering occurs at frequencies of 3.355 GHz and 3.965 GHz.

[0060] Figure 5These are transmission coefficient curves for the resonant structure model of this invention when three different resonant units are connected or fully connected to the feed microstrip line. Curve B123 shows the transmission coefficient when the first resonant unit 1, the second resonant unit 2, and the third resonant unit 3 are all connected to the rectangular feed microstrip line 5, where notch filtering occurs at frequencies of 3.11 GHz, 3.355 GHz, and 3.619 GHz; curve B124 shows the transmission coefficient when the first resonant unit 1, the second resonant unit 2, and the fourth resonant unit 4 are all connected to the rectangular feed microstrip line 5, where notch filtering also occurs at frequencies of 3.11 GHz, 3.619 GHz, and 3.965 GHz; curve B134 shows the transmission coefficient when the first resonant unit 1, the third resonant unit 3, and the fourth resonant unit 4 are all connected to the rectangular feed microstrip line 5. Notch filtering occurs at frequencies of 3.11 GHz, 3.355 GHz, and 3.965 GHz. Curve B234 represents the transmission coefficient when the second resonant unit 2, the third resonant unit 3, and the fourth resonant unit 4 are all connected to the rectangular feed microstrip line 5, at which point notch filtering occurs at frequencies of 3.355 GHz, 3.619 GHz, and 3.965 GHz. Curve B1234 represents the transmission coefficient when the first resonant unit 1, the second resonant unit 2, the third resonant unit 3, and the fourth resonant unit 4 are all connected to the rectangular feed microstrip line 5, at which point notch filtering occurs at frequencies of 3.11 GHz, 3.355 GHz, 3.619 GHz, and 3.965 GHz.

[0061] Reference Figure 3 , 4 As can be seen from Figure 5, although the frequency at which the notch appears shifts slightly and the notch depth is inconsistent, as long as the amplitude of the transmission coefficient at the observed frequency point is set to 15dB as the threshold, if the amplitude of the transmission coefficient at the frequency point is greater than 15dB, it is determined that the corresponding resonant unit is connected to the feed microstrip line; if the amplitude of the transmission coefficient at the frequency point is less than 15dB, it is determined that the corresponding resonant unit is not connected to the feed microstrip line; thus, it can be further deduced whether the corresponding finger joint is bent or not, achieving the purpose of independently recognizing the finger joint posture.

Claims

1. A chipless RFID gesture recognition sensor resonant structure model, characterized in that, The medium plate (6) is provided with a rectangular feeding microstrip line (5) on the top surface thereof along the transverse direction and near the upper edge; the top surface of the medium plate (6) is provided with a first resonant unit (1), a second resonant unit (2), a third resonant unit (3) and a fourth resonant unit (4) from left to right along the transverse direction; and the first resonant unit (1), the second resonant unit (2), the third resonant unit (3) and the fourth resonant unit (4) are located below the rectangular feeding microstrip line (5); and the bottom surface of the medium plate (6) is provided with a rectangular ground (7); The length of the first resonant unit (1) is 61.5mm±0.01 mm, the width is 3.5mm±0.1 mm, and the thickness is 0.1mm±0.01 mm; the length of the second resonant unit (2) is 52.5mm±0.01 mm, the width is 3.5mm±0.1 mm, and the thickness is 0.1mm±0.01 mm; the length of the third resonant unit (3) is 57mm±0.01 mm, the width is 3.5mm±0.1 mm, and the thickness is 0.1mm±0.01 mm; and the length of the fourth resonant unit (4) is 48mm±0.01 mm, the width is 3.5mm±0.1 mm, and the thickness is 0.1mm±0.01 mm; The distance between the first resonant unit (1) and the second resonant unit (2) is 9mm±0.1 mm; the distance between the second resonant unit (2) and the third resonant unit (3) is 12mm±0.1 mm; and the distance between the third resonant unit (3) and the fourth resonant unit (4) is 9mm±0.1 mm.

2. The chipless RFID gesture recognition sensor resonant structure model according to claim 1, wherein, The rectangular feeding microstrip line (5), the first resonant unit (1), the second resonant unit (2), the third resonant unit (3), the fourth resonant unit (4) and the rectangular ground (7) are all metal patches, and the medium plate (6) is made of cotton material.

3. The chipless RFID gesture recognition sensor resonant structure model according to claim 1, wherein, The length of the medium plate (6) is 74.5mm±0.1 mm, the width is 65mm±0.1 mm, and the thickness is 1mm±0.01 mm; and the length of the rectangular feeding microstrip line (5) is 65mm±0.1 mm, the width is 3.5mm±0.1 mm, and the thickness is 0.1mm±0.01 mm.

4. The chipless RFID gesture recognition sensor resonant structure model of claim 1, wherein, The distance between the top of the first resonant unit (1) and the bottom of the rectangular feeding microstrip line (5) is 2mm±0.01 mm; the distance between the top of the second resonant unit (2) and the bottom of the rectangular feeding microstrip line (5) is 0.5mm±0.01 mm; the distance between the top of the third resonant unit (3) and the bottom of the rectangular feeding microstrip line (5) is 2mm±0.01 mm; and the distance between the top of the fourth resonant unit (4) and the bottom of the rectangular feeding microstrip line (5) is 0.5mm±0.01 mm.

5. The chipless RFID gesture recognition sensor resonant structure model according to claim 3, wherein the length and width of the rectangular ground (7) are the same as those of the medium plate (6), and the thickness of the rectangular ground (7) is 0.1mm±0.01 mm.

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