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Highly Omnidirectional and Frequency Controllable Carbon/Polyaniline-based 2D and 3D Monopole Antenna.

Shin KY, Kim M, Lee JS, Jang J - Sci Rep (2015)

Bottom Line: Solvated C/PANI was synthesized by low-temperature interfacial polymerization, during which strong π-π interactions between graphene and the quinoid rings of PANI resulted in an expanded PANI conformation with enhanced crystallinity and improved mechanical and electrical properties.These antennas attained high peak gain (3.60 dBi), high directivity (3.91 dBi) and radiation efficiency (92.12%) relative to 2D monopole antenna.These improvements were attributed the high packing density and aspect ratios of C/PANI fibers and the removal of the flexible substrate.

View Article: PubMed Central - PubMed

Affiliation: World Class University program of Chemical Convergence for Energy &Environment, School of Chemical and Biological Engineering, Seoul National University, 151-742, Korea.

ABSTRACT
Highly omnidirectional and frequency controllable carbon/polyaniline (C/PANI)-based, two- (2D) and three-dimensional (3D) monopole antennas were fabricated using screen-printing and a one-step, dimensionally confined hydrothermal strategy, respectively. Solvated C/PANI was synthesized by low-temperature interfacial polymerization, during which strong π-π interactions between graphene and the quinoid rings of PANI resulted in an expanded PANI conformation with enhanced crystallinity and improved mechanical and electrical properties. Compared to antennas composed of pristine carbon or PANI-based 2D monopole structures, 2D monopole antennas composed of this enhanced hybrid material were highly efficient and amenable to high-frequency, omnidirectional electromagnetic waves. The mean frequency of C/PANI fiber-based 3D monopole antennas could be controlled by simply cutting and stretching the antenna. These antennas attained high peak gain (3.60 dBi), high directivity (3.91 dBi) and radiation efficiency (92.12%) relative to 2D monopole antenna. These improvements were attributed the high packing density and aspect ratios of C/PANI fibers and the removal of the flexible substrate. This approach offers a valuable and promising tool for producing highly omnidirectional and frequency-controllable, carbon-based monopole antennas for use in wireless networking communications on industrial, scientific, and medical (ISM) bands.

No MeSH data available.


Related in: MedlinePlus

The measured return loss curve of a 3D monopole antenna composed of a free-standing C/PANI fiber is shown (a) as a function of fiber length and (b) after stretching.The inset in (a) shows a free-standing, 10-cm C/PANI fiber-based monopole antenna. The length of these C/PANI fiber-based monopole antennas could be controlled by cutting them with scissors. The 10-cm fibers were stretched by 1, 3, and 5% along the x-axis. (c) Changes in transmitted power are shown as a function of stretching cycle and (d) the simulated radiation pattern of C/PANI-based 3D monopole antennas is shown.
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f6: The measured return loss curve of a 3D monopole antenna composed of a free-standing C/PANI fiber is shown (a) as a function of fiber length and (b) after stretching.The inset in (a) shows a free-standing, 10-cm C/PANI fiber-based monopole antenna. The length of these C/PANI fiber-based monopole antennas could be controlled by cutting them with scissors. The 10-cm fibers were stretched by 1, 3, and 5% along the x-axis. (c) Changes in transmitted power are shown as a function of stretching cycle and (d) the simulated radiation pattern of C/PANI-based 3D monopole antennas is shown.

Mentions: C/PANI fibers 10 cm in length were used as electrodes in 3D monopole antennas. Note that the length of these antennas can be adjusted by simply cutting the fibers with scissors. C/PANI-based 3D monopole antennas 3, 6, and 10 cm in length had center frequencies of 2.42, 1.04 GHz, and 601.3 MHZ, respectively (Fig. 6a). In general, resonant frequency decreased with increased antenna length. The high transmitted power efficiency (99.1%) of the 3-cm C/PANI-based 3D monopole antennas results from the high conductivity of the C/PANI, and the simulated RL value were also shown in Table 4. Furthermore, resonant frequencies decreased from 610.7 to 561.1 MHz as the 3D antennas were stretched to 1, 3, and 5% x-axis elongation from their original length of 10 cm (Fig. 6b). In addition, transmitted power efficiency decreased to 92.7% after 500 strain cycles. This demonstrates a high degree of structural stability in the C/PANI fibers when subject to an external force (Fig. 6c). The synthesized C/PANI-based 3D monopole antennas exhibited changes of less than 2% in their various properties over 3 months of storage in ambient conditions. Omnidirectional C/PANI-based 3D monopole antennas with high peak gains (3.60 dBi), directivity (3.91 dBi), and radiation efficiency (92.12%) were simulated (Table 5). These enhancements in these factors relative to those of 2D monopole antennas can be attributed to the high packing density and aspect ratio of the C/PANI fibers and the removal of the flexible substrate (Fig. 6d). However, stretching the C/PANI fibers resulted in a deterioration of performance due to a lowering in their mechanical strength, electrical conductivity and permittivity.


Highly Omnidirectional and Frequency Controllable Carbon/Polyaniline-based 2D and 3D Monopole Antenna.

Shin KY, Kim M, Lee JS, Jang J - Sci Rep (2015)

The measured return loss curve of a 3D monopole antenna composed of a free-standing C/PANI fiber is shown (a) as a function of fiber length and (b) after stretching.The inset in (a) shows a free-standing, 10-cm C/PANI fiber-based monopole antenna. The length of these C/PANI fiber-based monopole antennas could be controlled by cutting them with scissors. The 10-cm fibers were stretched by 1, 3, and 5% along the x-axis. (c) Changes in transmitted power are shown as a function of stretching cycle and (d) the simulated radiation pattern of C/PANI-based 3D monopole antennas is shown.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4559896&req=5

f6: The measured return loss curve of a 3D monopole antenna composed of a free-standing C/PANI fiber is shown (a) as a function of fiber length and (b) after stretching.The inset in (a) shows a free-standing, 10-cm C/PANI fiber-based monopole antenna. The length of these C/PANI fiber-based monopole antennas could be controlled by cutting them with scissors. The 10-cm fibers were stretched by 1, 3, and 5% along the x-axis. (c) Changes in transmitted power are shown as a function of stretching cycle and (d) the simulated radiation pattern of C/PANI-based 3D monopole antennas is shown.
Mentions: C/PANI fibers 10 cm in length were used as electrodes in 3D monopole antennas. Note that the length of these antennas can be adjusted by simply cutting the fibers with scissors. C/PANI-based 3D monopole antennas 3, 6, and 10 cm in length had center frequencies of 2.42, 1.04 GHz, and 601.3 MHZ, respectively (Fig. 6a). In general, resonant frequency decreased with increased antenna length. The high transmitted power efficiency (99.1%) of the 3-cm C/PANI-based 3D monopole antennas results from the high conductivity of the C/PANI, and the simulated RL value were also shown in Table 4. Furthermore, resonant frequencies decreased from 610.7 to 561.1 MHz as the 3D antennas were stretched to 1, 3, and 5% x-axis elongation from their original length of 10 cm (Fig. 6b). In addition, transmitted power efficiency decreased to 92.7% after 500 strain cycles. This demonstrates a high degree of structural stability in the C/PANI fibers when subject to an external force (Fig. 6c). The synthesized C/PANI-based 3D monopole antennas exhibited changes of less than 2% in their various properties over 3 months of storage in ambient conditions. Omnidirectional C/PANI-based 3D monopole antennas with high peak gains (3.60 dBi), directivity (3.91 dBi), and radiation efficiency (92.12%) were simulated (Table 5). These enhancements in these factors relative to those of 2D monopole antennas can be attributed to the high packing density and aspect ratio of the C/PANI fibers and the removal of the flexible substrate (Fig. 6d). However, stretching the C/PANI fibers resulted in a deterioration of performance due to a lowering in their mechanical strength, electrical conductivity and permittivity.

Bottom Line: Solvated C/PANI was synthesized by low-temperature interfacial polymerization, during which strong π-π interactions between graphene and the quinoid rings of PANI resulted in an expanded PANI conformation with enhanced crystallinity and improved mechanical and electrical properties.These antennas attained high peak gain (3.60 dBi), high directivity (3.91 dBi) and radiation efficiency (92.12%) relative to 2D monopole antenna.These improvements were attributed the high packing density and aspect ratios of C/PANI fibers and the removal of the flexible substrate.

View Article: PubMed Central - PubMed

Affiliation: World Class University program of Chemical Convergence for Energy &Environment, School of Chemical and Biological Engineering, Seoul National University, 151-742, Korea.

ABSTRACT
Highly omnidirectional and frequency controllable carbon/polyaniline (C/PANI)-based, two- (2D) and three-dimensional (3D) monopole antennas were fabricated using screen-printing and a one-step, dimensionally confined hydrothermal strategy, respectively. Solvated C/PANI was synthesized by low-temperature interfacial polymerization, during which strong π-π interactions between graphene and the quinoid rings of PANI resulted in an expanded PANI conformation with enhanced crystallinity and improved mechanical and electrical properties. Compared to antennas composed of pristine carbon or PANI-based 2D monopole structures, 2D monopole antennas composed of this enhanced hybrid material were highly efficient and amenable to high-frequency, omnidirectional electromagnetic waves. The mean frequency of C/PANI fiber-based 3D monopole antennas could be controlled by simply cutting and stretching the antenna. These antennas attained high peak gain (3.60 dBi), high directivity (3.91 dBi) and radiation efficiency (92.12%) relative to 2D monopole antenna. These improvements were attributed the high packing density and aspect ratios of C/PANI fibers and the removal of the flexible substrate. This approach offers a valuable and promising tool for producing highly omnidirectional and frequency-controllable, carbon-based monopole antennas for use in wireless networking communications on industrial, scientific, and medical (ISM) bands.

No MeSH data available.


Related in: MedlinePlus