• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.9 s.100
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• pp.949-956
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• 2005

In this paper, a new CPW-fed cross shape fractal antenna having a self-affinity is presented. This novel configuration, which has anisotropic scaling symmetry, makes smaller profile characteristic compared to the fractal antenna using a self-similarity. Increase of the iteration coefficient, which leads to decrease of the fundamental resonant frequency, shows a good impedance matching condition and multi-band characteristics due to new surface current paths. The radiation patterns are similar to those of monopole antennas. In the K3 stage of iteration, the proposed antenna shows a measured maximum gain 2.27 dBi at 940 MHz. A commercially available software based on the FDTD algorithm has been used to obtain the predicted results. In addition, an RT/Duroid 5880 substrate has been employed for the experimental results.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.2
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• pp.303-312
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• 2009

In this paper, we design and fabricate a disk sector antenna fed by CPW fur UWB communications. Also, we insert a rectangular slit on the arc-edge of the disk sector antenna. Then, the antenna has the directivity of E-면. In order to design the antenna, the input impedance is matched with the feed line of $50{\Omega}$ as varying the physical antenna parameters, which are the radius, the flare angle of disk sector, the length of ground, and the length of ground comer near by feed tine. Dimension of the antenna designed for UWB communication is $72mm{\times}26mm$ and bandwidth through computer simulation is $3{\sim}13GHz$. From the measured results, the bandwidth is $1.98{\sim}11GHz$. Return loss and gain of the fabricated antenna are -50.38dB, 1.34dBi at 3.5GHz, -12.27dB, 3.35dBi at 5.5GHz, -23.2dB, 3.8dBi at 8GHz and -16.17dB, 5.2dBi at 10GHz, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.1
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• pp.59-66
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• 2011

In this paper, a co-planar waveguide(CPW)-fed zeroth-order resonant(ZOR) antenna with an improved radiation efficiency was built and tested. The unit cell of the proposed antenna consists of a series metal-insulator-metal(MIM) capacitor and a shorted shunt stub inductor. In order to reduce the antenna size and to achieve the high radiation efficiency two shorted shunt stub arms bent by 90 degree were connected to the ground plane through the via. The proposed antenna consisting of two unit cells has an open ended composite right/left-handed(CRLH) transmission line structure. As a result the dominantly radiating parts of the antenna comes from shunt stub arms and vertical vias. The total size of the fabricated zeroth-order resonant antenna is $0.22\;{\lambda}_0{\times}0.22\;{\lambda}_0$. The measured gain and efficiency of the fabricated antenna have been enhanced by 3.07 dBi and 75 %, respectively, at the zeroth-order resonant frequency of 2.97 GHz.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.9
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• pp.777-782
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• 2015

In this paper, the compact CPW-fed antenna with triple folded patch for dual-band WLAN applications is proposed. As the conventional double inverted-L antenna is changed into the C-shaped patch and double inverted-L antenna, the antenna overcomes the narrow-band characteristics according to the miniaturization of the antenna. The proposed antenna with the size of only $16.5mm{\times}29.5mm{\times}1.0mm$ is designed and fabricated by optimized parameters to be operated at 2.4 GHz band and 5 GHz band. The antenna is fabricated into FR-4 substrate with thickness of 1.0 mm. We confirm that it is operated as antenna for WLAN applications by obtaining the measured return loss level of < -10 dB at dual-band.

• Journal of Advanced Navigation Technology
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• v.16 no.1
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• pp.27-34
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• 2012

In this paper, Coplanar waveguide(CPW)-fed slot loop antenna, which is applicable to the dual band(2.4GHz~2.4835GHz, 5.15GHz~5.825GHz) for the wireless LAN, is proposed. In order to miniaturize the proposed antenna, slot loop is bent by meandering. The resonant frequencies in the required dual band are adjusted by variation of the resonant length of slot loop as well as slot width. In particular, use of capacitive coupling CPW feed provides impedance matching without a seperate matching circuit, because the amount of electromagnetic coupling can be controlled by the offset between feed and radiator. As a result, it has been observed that the proposed antenna satisfies not only the required return loss(${\leq}10dB$) but also has high efficiency(${\geq}80%$) over the whole frequency band. In order to check the validity of the proposed antenna, some simulated results for return loss and radiation pattern are presented in comparison with the measured results.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.7
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• pp.761-767
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• 2012

In this paper, a novel ultra-wideband planar monopole antenna for the UHF communications and Digital-TV reception is proposed. The proposed antenna fed by a coplanar waveguide(CPW) is based on a triangular patch that has a broadband characteristic. To further increase the bandwidth of the triangular patch antenna, the top side of the regular triangular patch is loaded with a notch cut and each oblique side with a step. In addition, a slope is given to the ground plane of the CPW structure. Experimental results show that the -10 dB return loss bandwidth of the proposed antenna is 2,320 MHz from 480~2,800 MHz(5.83:1 bandwidth), which covers all the frequency bands of the various wireless communication systems and Digital TV broadcasting in the UHF band. Within the entire operating frequency range, the measured antenna gain in y-z plane(E-plane) varies from 3.01 to 4.71 dBi.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 1998.10a
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• pp.788-791
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• 1998

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.301-304
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• 1999

In general, printed antennas have a narrow bandwidth characteristic and many people want to find out the method of bandwidth improvement through complicated procedure. So we want to reform the conventional printed antenna characteristic by using the folded dipole's superiority to unit dipole. But it is hard to feed thr printed folded dipole antenna, we use the CPW, which is widely used in microwave IC or MMIC applications and have many advantage to the conventional microstrip line, to feed the folded slot antenna. It is confirmed that the improvement in the bandwidth characteristic of CPW fed folded slot antenna, as much as 20%, through the measurment of designed and implemented antenna.

• Transactions on Electrical and Electronic Materials
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• v.15 no.2
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• pp.55-59
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• 2014

An implantable CPW fed monopole antenna embedded into human tissue is proposed for ISM band biomedical applications. The proposed antenna is made compatible for implantation by embedding it in an alumina ceramic substrate (${\Box}_r=9.8$ and thickness=0.65 mm). The proposed antenna covers the ISM band of 2.45 GHz. The radiation parameters, such as return loss, E-Plane, H-Plane, are measured and analyzed, using the method of moments. The proposed antenna has substantial merits over other implanted antennas, like low profile, miniaturization, lower return loss, and better impedance matching and high gain.

• Transactions on Electrical and Electronic Materials
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• v.16 no.5
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• pp.250-253
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• 2015

A novel implantable CPW fed Apollian shaped antenna embedded into human tissue is proposed for ISM band biomedical applications. The proposed antenna is made compatible for implantation by embedding it in an alumina ceramic substrate(ε_r=9.8 and thickness= 0.65 mm). The proposed antenna covers the ISM band of 2.45 GHz. The radiation parameters such as return loss, xy-plane, xz-plane, and yz-plane etc., are measured and analyzed using the agilent vector network analyzer. The proposed antenna has substantial advantages, including low profile, miniaturization ability, lower return loss, better impedance matching, and high gain over conventional implanted antennas.