• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.28 no.6
• /
• pp.505-508
• /
• 2017

This paper analyzes the effect of metal dummy structures in CMOS on antenna performances of a sub-terahertz on-chip microstrip patch antenna. A 400-GHz on-chip antenna is designed in a 45-nm CMOS process, and the resonance frequency and efficiency of the antenna are analyzed depending on the density of metal dummy structures. Antennas integrated with an oscillator are designed and fabricated for verification, and measurements are performed using quasi-optical methods with an FTIR and bolometer. The measurement results shows that the radiated power drops from 420 nW to 90 nW by 6.8 dB due to the dummy structures with the density of 27 %.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.24 no.7
• /
• pp.960-966
• /
• 2018

Communication antennas used at sea have been developed remarkably. However, the speed of this development is insufficient when compared with user demands. Therefore, we developed an antenna for UWB/Bluetooth that operates on 3 [GHz] and 5.72 [GHz] bands in order to use the high-speed communication network system which improved antenna miniaturization, gain and radiation patterns. To improve bandwidth, a microstrip patch antenna was selected and CST Microwave Studio 2014 program was used. Through the program, we calculated the slot width, length, transmission line width, etc. using a theoretical formula at each step. These figures were checked through simulation to see if they meet production standards. UWB for high-speed wireless communication for short-range communication at sea, Bluetooth for exchanging information at a short distance by connecting each device, and corresponding technology can be easily utilized.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.47 no.1
• /
• pp.77-83
• /
• 2010

Radiation characteristics of $5{\times}4$ pin array patch antennas are compared to those of $5{\times}2$ pin array patch antennas for several substrate thicknesses using the computer simulation. Since the number of unit cells of a $5{\times}2$ pin array patch antenna is half of that of a $5{\times}4$ pin array patch antenna, the number of pins used in a $5{\times}2$ pin array patch antenna is half of that in a $5{\times}4$ pin array patch antenna and the patch width of a $5{\times}2$ pin array patch antenna is very small compared to that of a $5{\times}4$ pin array patch antenna. However, the radiation characteristics of a $5{\times}2$ pin array patch antenna are almost similar to those of a $5{\times}4$ pin array patch antenna.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.14 no.1
• /
• pp.119-124
• /
• 2014

In this paper, A GSm/WCDMA band antenna which can be confirmed positioning information of a container by using the GPS/GLONASS bands on one board and can be sent the positioning information to the mobile communication network in real time is designed. A microstrip patch antennas which supports dual-band (GPS and GLONASS) was optimized. The antenna size is $25{\times}25{\times}5[mm]$. A chip monopole antennas which supports dual-band (GSM and WCDMA) was optimized. The antenna size is $27{\times}8{\times}3.2[mm]$. To amplify the Satellite reception signal level, two-stage low noise amplifier(LNA) was designed. The LNA gain is 27[dB]. The size of Jig for antennas measuring is $100{\times}30{\times}1[mm]$.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.7
• /
• pp.613-619
• /
• 2015

In this paper, we proposed a paper-based pattern-switchable antenna using inkjet-printing technology. The proposed antenna is composed of two bow-tie antennas and a switching network. The bow-tie antennas are inkjet-printed on paper using a low cost home printer. The switching network is built on a printed-circuit-board(PCB) and consists of a single-pole-double-throw(SPDT) switch and balun element. A double-sided parallel-strip line(DSPSL) can convert the unbalanced microstrip mode to the balanced strip mode. Two bow-tie antennas have different radiation patterns because of the different orientation of the reflectors. It is demonstrated from EM simulation and measurement that the radiation patterns of the proposed antenna are successfully switched by the SPDT.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.6
• /
• pp.525-532
• /
• 2015

In this paper, we propose an equivalent model of array antennas that use open-ended waveguides for effective EM simulation. We first investigate an individual element that consists of an open-ended waveguide and square ground plane. The waveguide length, aperture size, and ground size of the individual element are adjusted to give a similar radiation pattern to that of the individual element of the original antenna. We then apply the designed equivalent model to two different types of array antennas, such as a microstrip patch array and a waveguide array antenna. Comparison of the simulation results using the equivalent model with the results obtained with the original antenna reveals a difference in gain of less than 0.2 dB and a difference in half power beam width(HPBW) of less than $1^{\circ}$. The designed equivalent model is then mounted on a simple aircraft, and the simulation results are again compared to results from the original antenna. We find a 60 % reduction in simulation resources and time when compared with the original antenna model.

• Journal of the Institute of Electronics Engineers of Korea TE
• /
• v.37 no.1
• /
• pp.63-69
• /
• 2000

The high-$T_c$ Superconducting (HTS) antenna which consists of "H" type resonator has the benefits for the miniaturization of antenna in comparison with the microstrip antenna of the similar dimension. To fabricate the "H" type antenna, HTS $YBa_2Cu_3O_{7-x}$ (YBCO) thin films were deposited on MgO substrates using rf-magnetron sputtering. Standard etching processes were performed for the patterning of the "H" type antenna. For comparison between normal conducting antennas and superconducting antennas, the gold antennas with the same dimension were also fabricated. An aperture coupling was used for impedance matching between $50{\Omega}$ feed line and HTS radiating patch. The diverse experimental results were reported in terms of the resonant frequency, the return loss and the characteristics impedance. The "H" type superconducting antenna showed the performance of 1.36 in SWR, 24% in efficiency, and 14.6 dB in the return loss superior of the normal conducting counterpart.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.9
• /
• pp.2246-2252
• /
• 2009

A new metamaterial antenna with dual resonant modes is presented using an asymmetrical periodic arrangement for orthogonal radiation patterns. The proposed antenna produces two orthogonal modes by the asymmetrical periodic unit-cell arrangement. The orthogonal resonant mode provides perpendicular radiation patterns without changing the antenna polarization at each resonant mode. The fabricated antenna shows good agreements with the theoretical analysis of the electric-field. The experimental results shows the orthogonal radiation patterns along x- and y-axises, and gains are 3.34 and 3.86 dBi at each radiating resonant mode, respectively. Additionally, slotted ground structures are embedded on the back side of the antenna in order to reduce the size and enhance the radiation efficiency of 12 % and 27 %, respectively.

• Journal of IKEEE
• /
• v.26 no.1
• /
• pp.137-140
• /
• 2022

In this paper, we proposed a new W-band monopulse tracking system based on reflectarray antenna structure. The proposed reflectarray antenna monopulse tracking system consists of four feed horn antennas and a planar reflector using a microstrip reflectarray. The four feed horn antennas have a gain of 10 dBi and a half-power beam-width of 56 degrees symmetrically in the E/H plane. It was confirmed that the reflectarray antenna using one feed horn antenna has a size of 41.8 × 41.8 mm², a gain of 26.8 dBi, and a half-power beam-width of about 5.6 degrees. The reflectarray monopulse tracking system using 4 feeding horn antennas is well matched from 75 GHz to 90 GHz, and the isolation is secured by more than 10 dB. Finally, the proposed system shows the tracking range of 5.98 degrees and the tracking error range was 0.02 degrees.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.2
• /
• pp.111-118
• /
• 2016

This paper presents an X-band (9.375 GHz) $1{\times}2$ array microstrip antenna which is capable of active beam compensation for installation of an unmanned aerial vehicle (UAV). First of all, a basic $1{\times}2$ array microstrip antenna incorporated with wilkinson power divider was designed and performance of the array antenna was verified. Next, to verify beam steering performance of the designed array microstrip antenna, we fabricated a phase shifter, and the wilkinson power divider as module structure and measured characteristics of beam steering according to phase shifting. The main lobe is 0.6 dBi at $0^{\circ}$, and the side lobe decreased 18.8 dB. The reliable radiation pattern was achieved. Finally, an active beam steering microstrip array antenna attached with the phase shifter and the power divider on the back side of the antenna was designed and fabricated to install wing of UAV for compactness. The maximum gain is 0.1 dBi. Therefore, we obtained a basic antenna technology for compensating beam error according to wing deformation of an UAV installed array antennas.