A broadband wearable dual-band filtering antenna with independently controllable radiation zeros

Abstract

The application discloses a broadband wearable dual-frequency filtering antenna with independently controllable radiation zero points, which adopts a double-layer dielectric substrate structure, wherein an upper layer is a Rogers4350B substrate, and a lower layer is a flexible felt substrate; through multi-structure coupling design of a rectangular radiation patch integrated with a T-shaped strip, a U-shaped groove, a rectangular groove and a parasitic strip, dual-frequency operation and independent regulation and control of radiation zero points are realized; the T-shaped strip generates dual-frequency characteristics and a first radiation zero point between two frequency bands; the U-shaped groove regulates a low-frequency zero point and widens a low-frequency bandwidth; the rectangular groove introduces a second radiation zero point between two frequency bands and expands a high-frequency bandwidth; and the parasitic strip introduces a high-frequency zero point, a new resonance point and a widened high-frequency matching bandwidth. The application has flexible wearable characteristics, broadband performance and independently controllable radiation zero point characteristics, and is suitable for wireless communication scenes such as WiMAX / WLAN.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a broadband wearable dual-frequency filter antenna with independently controllable radiation null point and a wireless communication device. Background Technology

[0002] With the rapid development of wireless communication technology, users are increasingly demanding miniaturized, multifunctional, and high-performance communication devices. Filtered antennas, as an emerging technology, can improve the spectrum utilization and anti-interference capabilities of a system. However, existing filtered antennas are mostly based on rigid substrates, making it difficult to meet the requirements of wearable devices for flexibility, lightweight design, and comfort. Most only support single-band operation, failing to meet the needs of dual-band communication. Furthermore, the radiation null point of traditional filtered antennas is difficult to independently control, limiting their performance optimization. The proposed broadband wearable dual-band filtered antenna with independently controllable radiation null points helps improve filtering characteristics and adapt to complex wireless environments. Summary of the Invention

[0003] The primary objective of this invention is to overcome the shortcomings and deficiencies of the prior art and provide a broadband wearable dual-band filtering antenna with independently controllable radiation null point. This antenna, while meeting the requirements of wearable devices, possesses excellent broadband characteristics and stable gain, and simultaneously achieves dual-band operation. Furthermore, through independently controllable radiation null point adjustment technology, it optimizes filtering performance and anti-interference capabilities, improves spectrum utilization, and meets the needs of modern wireless communication devices.

[0004] A second objective of the present invention is to provide a wireless communication device.

[0005] The first objective of this invention is achieved through the following technical solution: a broadband wearable dual-band filter antenna with independently controllable radiation null point, comprising a first dielectric substrate, a second dielectric substrate, a ground plane, a rectangular radiating patch, a T-shaped strip, a U-shaped slot, a rectangular slot, a parasitic strip, and a coaxial probe; the first dielectric substrate is stacked on top of the second dielectric substrate, with an air gap between them; the rectangular radiating patch is disposed on the upper surface of the first dielectric substrate; the T-shaped strip is located in front of the upper edge of the rectangular radiating patch, and the vertical edge of the T-shaped strip is connected to the upper edge of the rectangular radiating patch, for generating dual-band characteristics and the first radiation between the two frequency bands. The U-shaped groove is located slightly below the center of the rectangular radiating patch, used to generate a low-frequency radiation null and a new resonant point, as well as to widen the low-frequency matching bandwidth. The coaxial probe passes through the rectangular radiating patch, the first dielectric substrate, and the second dielectric substrate, and approaches the lower edge of the rectangular radiating patch. The rectangular groove is located on both sides of the U-shaped groove, used to generate a second radiation null and a new resonant point between the two frequency bands, as well as to widen the high-frequency matching bandwidth. The parasitic stripe is located on the left and right sides of the rectangular radiating patch, used to generate a high-frequency radiation null and a new resonant point, as well as to widen the high-frequency matching bandwidth. The ground plane is set on the lower surface of the second dielectric substrate.

[0006] Preferably, the length of the U-shaped groove is half the wavelength corresponding to the zero frequency of low-frequency radiation. By controlling the length of the U-shaped groove, the left and right movement of the zero frequency of low-frequency radiation can be controlled.

[0007] Preferably, the T-shaped strip controls the first radiation null point between the two frequency bands, and the left and right movement of the first radiation null point between the two frequency bands can be controlled by controlling the length of the T-shaped strip.

[0008] Preferably, the length of the rectangular slot is one-quarter of the wavelength corresponding to the second radiation null frequency between the two frequency bands. By controlling the length of the rectangular slot, the left and right movement of the second radiation null between the two frequency bands can be controlled.

[0009] Preferably, the length of the parasitic strip is half the wavelength corresponding to the zero-point frequency of high-frequency radiation. By controlling the length of the parasitic strip, the left and right movement of the zero-point of high-frequency radiation can be controlled.

[0010] Preferably, the rectangular radiating patch is located at the middle position on the upper surface of the first dielectric substrate, and the rectangular radiating patch, T-shaped strip, U-shaped groove, rectangular groove, and parasitic strip are symmetrical about the center line of the first dielectric substrate, and the ground plane is symmetrical about the center line of the second dielectric substrate.

[0011] Preferably, the opening of the U-shaped groove faces the upper edge of the rectangular radiating patch.

[0012] Preferably, the rectangular radiating patch has two parasitic strips on each of its left and right sides, and they are distributed in a front-to-back pattern.

[0013] Preferably, the ground surface covers the entire lower surface of the second dielectric substrate.

[0014] Preferably, the dielectric material used in the first dielectric substrate is Rogers 4350B, with a dielectric constant of 3.66 and a loss tangent of 0.0037.

[0015] Preferably, the dielectric material used in the second dielectric substrate is a flexible and bendable felt material with a dielectric constant of 1.2 and a loss tangent of 0.2.

[0016] Preferably, the ground material is conductive nylon fabric with a surface resistivity of less than 0.009 Ω / m. 2 .

[0017] Preferably, the rectangular radiating patch is made of copper.

[0018] The second objective of this invention is achieved through the following technical solution: a wireless communication device, including the aforementioned broadband wearable dual-frequency filtering antenna with independently controllable radiation null point.

[0019] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0020] 1. The antenna of this invention generates dual-frequency characteristics and introduces a radiation null at low frequencies by loading a T-shaped stripe onto a rectangular radiating patch; by loading a U-shaped slot, it introduces a new resonant point while simultaneously introducing a radiation null at low frequencies and widens the low-frequency matching bandwidth; loading rectangular slots on both sides of the U-shaped slot further optimizes the filtering performance between the two frequency bands and widens the high-frequency matching bandwidth; by loading parasitic stripes, it introduces a new resonant point while simultaneously introducing a radiation null at high frequencies and widens the high-frequency matching bandwidth. Ultimately, this antenna achieves dual-frequency filtering characteristics, independent controllability of the radiation null, and excellent broadband characteristics.

[0021] 2. The antenna of this invention employs a combination of T-shaped stripes, U-shaped slots, rectangular slots, and parasitic stripes loaded onto a rectangular radiating patch, achieving a broadband wearable dual-band filtered antenna with independently controllable radiation null points. The antenna's low-frequency matching bandwidth is 8.6% (3.33-3.63GHz), and its high-frequency matching bandwidth is 24.8% (5.01-6.42GHz), satisfying broadband characteristics. The peak gains within the passband are 7.7dBi and 10.7dBi, respectively, and the out-of-band rejection level is higher than 14.5dB. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention.

[0023] Figure 2 This is a top view of the upper dielectric substrate of the broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention.

[0024] Figure 3 This is a cross-sectional view of a broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention.

[0025] Figure 4 The above is an S-parameter diagram of a broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention.

[0026] Figure 5 This is a gain curve of a broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention.

[0027] Figure 6 The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the E-plane radiation field pattern at 3.38 GHz.

[0028] Figure 7 The radiation pattern of the broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the H-plane radiation field pattern at 3.38 GHz.

[0029] Figure 8 The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the E-plane radiation field pattern at 3.58 GHz.

[0030] Figure 9 The radiation pattern of the broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the H-plane radiation field pattern at 3.58 GHz.

[0031] Figure 10 The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the E-plane radiation field pattern at 5.14 GHz.

[0032] Figure 11 The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the H-plane radiation field pattern at 5.14 GHz.

[0033] Figure 12 The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the E-plane radiation field pattern at 5.68 GHz.

[0034] Figure 13 The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the H-plane radiation field pattern at 5.68 GHz.

[0035] Figure 14The radiation pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the E-plane radiation field pattern at 6.32 GHz.

[0036] Figure 15 The radiation pattern of the broadband wearable dual-frequency filter antenna with independently controllable radiation null point according to an embodiment of the present invention is shown in the H-plane radiation field pattern at 6.32 GHz.

[0037] Figure 16 This is a schematic diagram of the structure of a broadband wearable dual-frequency filter antenna with independently controllable radiation null point, loaded with a three-layer human tissue model, according to an embodiment of the present invention.

[0038] Figure 17 The image shows the S-parameters of a three-layer human tissue model loaded with a broadband wearable dual-frequency filter antenna with independently controllable radiation null point, as described in an embodiment of the present invention.

[0039] Figure 18 This is a SAR value diagram at 3.5 GHz for a broadband wearable dual-frequency filter antenna with independently controllable radiation null point, loaded with a three-layer human tissue model according to an embodiment of the present invention.

[0040] Figure 19 This is a SAR value diagram at 5.5 GHz for a broadband wearable dual-frequency filter antenna with independently controllable radiation null point, loaded with a three-layer human tissue model according to an embodiment of the present invention. Detailed Implementation

[0041] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0042] Example 1

[0043] This implementation discloses a broadband wearable dual-band filter antenna with independently controllable radiation null point. Through structural innovation, it achieves dual-band operation, broadband matching, and flexible adjustment of the radiation null point, while simultaneously meeting the flexibility and human safety requirements of wearable devices. See also... Figures 1 to 3 As shown, it includes a first dielectric substrate 3, a second dielectric substrate 2, a ground plane 1, a rectangular radiating patch 4, a T-shaped strip 5, a U-shaped groove 8, a rectangular groove 7, a parasitic strip 9, and a coaxial probe 6. The first dielectric substrate 3 is stacked on top of the second dielectric substrate 2. The T-shaped strip 5 is located in front of the upper edge of the rectangular radiating patch 4, and the vertical edge of the T-shaped strip 5 is connected to the upper edge of the rectangular radiating patch 4. The rectangular radiating patch 4 is located in the middle of the upper surface of the first dielectric substrate 3. The U-shaped groove 8 is located slightly below the middle of the rectangular radiating patch 4, and its opening faces the upper edge of the rectangular radiating patch 4. The coaxial probe 6 passes through the rectangular radiating patch 4, the first dielectric substrate 3, and the second dielectric substrate 2, and is close to the lower edge of the rectangular radiating patch 4. The rectangular groove 7 is located on both sides of the U-shaped groove 8, and the parasitic strip 9 is located on the left and right sides of the rectangular radiating patch 4.

[0044] In this embodiment, a T-shaped strip 5 is loaded onto a rectangular radiating patch 4 to generate dual-frequency characteristics and introduce the first radiation null in the low-frequency band. By loading a U-shaped groove 8, a new resonant point is excited while introducing the radiation null in the low-frequency band, thus widening the low-frequency matching bandwidth. The length of the U-shaped groove 8 is half the wavelength corresponding to the low-frequency radiation null frequency, and its length can be adjusted to independently control the frequency position of the low-frequency radiation null.

[0045] Furthermore, by loading symmetrical rectangular slots 7 on both sides of the U-shaped slot 8, a second radiation null is introduced between the two frequency bands, and a new high-frequency resonant point is excited, thereby expanding the high-frequency matching bandwidth. The length of the rectangular slot 7 is one-quarter of the wavelength corresponding to the radiation null frequency, and the position of the null can be independently adjusted by adjusting its size.

[0046] Furthermore, by loading the parasitic strip 9, a radiation null is introduced in the high-frequency band, further widening the high-frequency bandwidth. The length of the parasitic strip 9 is half the wavelength corresponding to the high-frequency radiation null frequency, and its size variation can precisely adjust the high-frequency null frequency.

[0047] Preferably, the rectangular radiating patch 4, the T-shaped strip 5, the U-shaped groove 8, the rectangular groove 7, and the parasitic strip 9 are symmetrical about the center line of the first dielectric substrate 3, and the ground plane 1 is symmetrical about the center line of the second dielectric substrate 2.

[0048] Preferably, the first dielectric substrate 3 is a Rogers 4350B (dielectric constant 3.66, loss tangent 0.0037), and the second dielectric substrate 2 is a flexible felt (dielectric constant 1.2, loss tangent 0.2).

[0049] Preferably, the ground surface 1 is made of conductive nylon fabric (resistivity <0.009Ω / m). 2 The rectangular radiating patch 4 is made of copper.

[0050] Preferably, the ground surface 1 covers the entire lower surface of the second dielectric substrate 2.

[0051] See Figure 4 The figure shows the S-parameter simulation curves of the broadband wearable dual-band filter antenna with independently controllable radiation null point described in this embodiment. From the figure, we can see the antenna's |S... 11 The |<-10dB bandwidths are 3.33-3.63GHz (8.6%) and 5.01-6.42GHz (24.8%), respectively, and are applied to the 3.5GHz WiMAX band (3.4-3.6GHz) and the 5GHz WLAN band (5.15-5.825GHz).

[0052] See Figure 5The figure shows the gain simulation curve of the broadband wearable dual-band filter antenna with independently controllable radiation nulls described in this embodiment. The peak gain in the passband reaches 7.7 dBi (low frequency) and 10.7 dBi (high frequency). Four radiation nulls are introduced at 3.18, 4.12, 4.58 and 6.72 GHz on the gain curve, and the out-of-band rejection level is higher than 14.5 dB.

[0053] See Figure 6 and Figure 7 The figure shows the radiation field pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point at 3.38 GHz in this embodiment, specifically the E-plane and H-plane radiation field patterns. As can be seen from the figure, the antenna has good directional radiation characteristics at this frequency, with a cross-polarization ratio greater than 35 dB and a front-to-back ratio greater than 18 dB.

[0054] See Figure 8 and Figure 9 The figure shows the radiation field pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point at 3.58 GHz in this embodiment, specifically the E-plane and H-plane radiation field patterns. As can be seen from the figure, the antenna has good directional radiation characteristics at this frequency, with a cross-polarization ratio greater than 35 dB and a front-to-back ratio greater than 18 dB.

[0055] See Figure 10 and Figure 11 The figure shows the radiation field pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point at 5.14 GHz in this embodiment, specifically the E-plane and H-plane radiation field patterns. As can be seen from the figure, the antenna has good directional radiation characteristics at this frequency, with a cross-polarization ratio greater than 51 dB and a front-to-back ratio greater than 15 dB.

[0056] See Figure 12 and Figure 13 The figure shows the radiation field pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point at 5.68 GHz in this embodiment, specifically the E-plane and H-plane radiation field patterns. As can be seen from the figure, the antenna has good directional radiation characteristics at this frequency, with a cross-polarization ratio greater than 50 dB and a front-to-back ratio greater than 15 dB.

[0057] See Figure 14 and Figure 15 The figure shows the radiation field pattern of the broadband wearable dual-band filter antenna with independently controllable radiation null point at 6.32 GHz in this embodiment, specifically the E-plane and H-plane radiation field patterns. As can be seen from the figure, the antenna has good directional radiation characteristics at this frequency, with a cross-polarization ratio greater than 42 dB and a front-to-back ratio greater than 16 dB.

[0058] See Figure 16The diagram shown illustrates the structure of the broadband wearable dual-band filter antenna with independently controllable radiation null point, as described in this embodiment, loaded with a three-layer human tissue model. The loading of the three-layer human tissue model simulates the impact of human body loading on antenna performance and simultaneously assesses whether the antenna's radiation to the human body meets safety standards.

[0059] See Figure 17 The figure shows the S-parameters of the broadband wearable dual-band filter antenna with independently controllable radiation null point in this embodiment, loaded with a three-layer human tissue model. As can be seen from the figure, after loading three layers of human tissue, the bandwidth narrows to some extent, to 3.35-3.63GHz (8.0%) and 5.02-6.42GHz (24.4%). However, it can still cover the 3.5GHz WiMAX band and the 5GHz WLAN band, meeting the usage requirements.

[0060] See Figure 18 and Figure 19 The figure shows the SAR values ​​of the broadband wearable dual-frequency filter antenna with independently controllable radiation null point in this embodiment, loaded with a three-layer human tissue model, at 3.5 GHz and 5.5 GHz. As can be seen from the figure, the maximum SAR values ​​of the antenna are 0.0647 W / kg and 0.0964 W / kg, respectively, which are far less than the international safety standard of 1.6 W / kg.

[0061] In summary, this invention achieves dual-frequency operation by loading a T-shaped strip onto a rectangular radiating patch, and introduces a first radiation null between the two frequency bands. By loading a U-shaped groove onto the rectangular radiating patch, not only is a low-frequency radiation null introduced, but the bandwidth is further widened. The length of the U-shaped groove is approximately half the wavelength corresponding to the low-frequency radiation null frequency, and its length can be adjusted to precisely control the null position. Furthermore, by loading a rectangular groove, a second radiation null is introduced between the two frequency bands, exciting a new high-frequency resonant point and further expanding the high-frequency bandwidth. The length of the rectangular groove is approximately one-quarter the wavelength of the corresponding radiation null frequency, and its size can be independently adjusted to control the high-frequency null position. By loading a parasitic strip, a radiation null is introduced in the high-frequency band, further widening the high-frequency bandwidth. The length of the parasitic strip is approximately half the wavelength corresponding to the high-frequency radiation null frequency, which can be used to precisely adjust the high-frequency null frequency. In addition, a three-layer human tissue model was loaded to evaluate the antenna's performance in a real wearable environment, ensuring that the bandwidth and radiation characteristics met the requirements. Ultimately, a |S11|<-10dB bandwidth of 3.33-3.63GHz (8.6%) and 5.01-6.42GHz (24.8%) was achieved, with in-band peak gains of 7.7dBi (low frequency) and 10.7dBi (high frequency), respectively. The out-of-band suppression level was higher than 14.5dB, and the maximum SAR values ​​were 0.0647W / kg and 0.0964W / kg, respectively, which are far less than the international safety standard of 1.6W / kg, ensuring the antenna's safety and wearability.

[0062] Example 2

[0063] This embodiment provides a wireless communication device, including the broadband wearable dual-frequency filter antenna with independently controllable radiation null point as described in Embodiment 1.

[0064] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A broadband wearable dual-band filter antenna with independently controllable radiation null point, characterized in that, The system includes a first dielectric substrate (3), a second dielectric substrate (2), a ground plane (1), a rectangular radiating patch (4), a T-shaped strip (5), a U-shaped groove (8), a rectangular groove (7), a parasitic strip (9), and a coaxial probe (6). The first dielectric substrate (3) is stacked on top of the second dielectric substrate (2), with an air gap between them. The rectangular radiating patch (4) is disposed on the upper surface of the first dielectric substrate (3). The T-shaped strip (5) is located in front of the upper edge of the rectangular radiating patch (4), and the vertical edge of the T-shaped strip (5) is connected to the upper edge of the rectangular radiating patch (4) to generate dual-frequency characteristics and the first radiation null point between the two frequency bands. The U-shaped groove (8) is located in front of the rectangular radiating patch (4). The lower center of the radiating patch (4) is used to generate a low-frequency radiation null and a new resonant point, as well as to broaden the low-frequency matching bandwidth. The coaxial probe (6) passes through the rectangular radiating patch (4), the first dielectric substrate (3), and the second dielectric substrate (2), and is close to the lower edge of the rectangular radiating patch (4). The rectangular groove (7) is located on both sides of the U-shaped groove (8), used to generate a second radiation null and a new resonant point between the two frequency bands, as well as to broaden the high-frequency matching bandwidth. The parasitic strip (9) is located on the left and right sides of the rectangular radiating patch (4), used to generate a high-frequency radiation null and a new resonant point, as well as to broaden the high-frequency matching bandwidth. The ground plane (1) is set on the lower surface of the second dielectric substrate (2).

2. The broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The length of the U-shaped groove (8) is half the wavelength corresponding to the zero frequency of low-frequency radiation. By controlling the length of the U-shaped groove (8), the left and right movement of the zero frequency of low-frequency radiation can be controlled.

3. The broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The T-shaped strip (5) controls the first radiation null point between the two frequency bands. By controlling the length of the T-shaped strip (5), the left and right movement of the first radiation null point between the two frequency bands can be controlled.

4. The broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The length of the rectangular slot (7) is one-quarter of the wavelength corresponding to the second radiation null frequency between the two frequency bands. By controlling the length of the rectangular slot (7), the left and right movement of the second radiation null between the two frequency bands can be controlled.

5. A broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The length of the parasitic strip (9) is half the wavelength corresponding to the zero frequency of high-frequency radiation. By controlling the length of the parasitic strip (9), the left and right movement of the zero frequency of high-frequency radiation can be controlled.

6. The broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The rectangular radiating patch (4) is located in the middle of the upper surface of the first dielectric substrate (3). The rectangular radiating patch (4), T-shaped strip (5), U-shaped groove (8), rectangular groove (7), and parasitic strip (9) are symmetrical about the center line of the first dielectric substrate (3). The ground (1) is symmetrical about the center line of the second dielectric substrate (2).

7. A broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The opening of the U-shaped groove (8) faces the top of the rectangular radiating patch (4).

8. A broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The rectangular radiation patch (4) has two parasitic strips (9) on each of its left and right sides, and they are distributed in a front-to-back pattern.

9. A broadband wearable dual-band filter antenna with independently controllable radiation null point according to claim 1, characterized in that, The ground (1) covers the entire lower surface of the second dielectric substrate (2).

10. A wireless communication device, characterized in that, Includes the broadband wearable dual-frequency filter antenna with independently controllable radiation null point as described in any one of claims 1-9.

Images