• JSTS:Journal of Semiconductor Technology and Science
• /
• v.5 no.3
• /
• pp.204-209
• /
• 2005

A small size broadband microstrip patch antenna with small ground plane has been fabricated using MEMS. Multiple layer substrates are used to realize small size and broadband characteristics. The microstrip patch is divided into 3 pieces and each patch is connected to each other using a metal microstrip line. The fabrication process is simple and only one mask is needed. Two types of microtrip antennas are fabricated. Type A is the micros trip antenna with metal lines and type B is the microstrip antenna without metal lines. The size of proposed microstip antenna is $8^{*}12^{*}2mm^{3}$ and the experimental results show that the antenna type A and type B have the bandwidth of 420 MHz at 5.3 GHz and 480 MHz at 5.66 GHz, respectively.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.603-604
• /
• 2006

A small size broadband microstrip patch antenna with small ground plane has been fabricated using MEMS. Multiple layer of high and low dielectric substrates are used to realize small size and broadband characteristics. The microstrip patch is divided into 4 pieces and each patch is connected to each other using a metal microstrip line. The fabrication process is very simple and only one mask is needed. Two types of microtrip antennas are fabricated. Type A is the microstrip antenna with metal lines and type B is the microstrip antenna without metal lines. The size of proposed microstip antenna is $8*12*2mm^3$ and the experimental results show that the antenna type A and type B have the bandwidth of 420MHz at 5.3 GHz and 480MHz at 5.66 GHz, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.380-381
• /
• 2006

A technique to control the operating frequency of microstrip antenna by using the X-cut quartz substrate has been investigated experimentally and theoretically. We consider 6, 8 and 10 GHz resonance frequency in three dimensional quartz plates. Equation of linear piezoelectricity are solved for the thickness-shear approximation of X-cut quartz plates. At X-band frequencies, the microstrip antenna was voltage-controllable using the dc electric field dependence of the piezoelectric constant of X-cut quartz. This work demonstrates advantageous application for X-cut quartz plate in microstrip antenna substrates.

• 제어로봇시스템학회:학술대회논문집
• /
• 2004.08a
• /
• pp.466-469
• /
• 2004

In this paper, we improve the matching impedance of antennas by inserting parasitic slots on the ground plane of right-angle triangular slot antennas. The designed antennas characteristics are analyzed by using Finite Different Time Domain (FDTD) method, the specific design frequency is 10 GHz and match impedance is 50 ohms. Simulation results show that the efficient of return loss and radiation patterns are improved and enhance. In this case, the right-angle triangular slot antennas with parasitic slots have matching impedance better than antennas without parasitic slots.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.14 no.8
• /
• pp.787-795
• /
• 2003

Three types of array antennas are developed for broadcasting band of Koreasat III. First, the specification of the array antenna is decided. Second, characteristics and advantages of three types of antennas using the radial waveguide characteristics is investigated and discussed. Third, design method fur those antenna is studied to meet antenna specifications, and then antennas are designed and tested. Finally, it is concluded that these types of antennas can be efficiently design compared to both parabola antennas and microstrip array within the limited size.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.1
• /
• pp.331-337
• /
• 2015

A novel fully-printed microstrip antenna with negative first resonance and dual polarization is proposed. The radiator is printed on the 1-layer substrate instead of multilayers. The -1st resonance results from a composite right- and left-handed(CRLH) structure that has a circumferentially interlocked gap capacitively coupling a patch with a shorted-ring. This compact antenna is provided with a dual-polarization capability by creating two orthogonal linear polarizations in one body with coaxial feeds. The design is carried out by doing full-wave EM field simulation which is compared with the measurement of the fabricated antenna prototype. The measured results give the gain of 5 dBi and the efficiency of 78% at the -1st resonance mode as the center frequency of a downlink channel of the bandwidth over 20 MHz with 29 dB polarization isolation for mobile communication.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.1 no.2
• /
• pp.131-136
• /
• 1997

In this paper, the input impedance of coaxial fed rectangular microstrip patch antenna located inside rectangular waveguide is calculated by using the cavity model and the mode excited in the waveguide by the patch antenna. The return loss and efficiency of the patch antennas as a function of feed position in. free space and in waveguide are calculated and compared. The maximum efficiency of the antennas in waveguide and in free space are obtained at different feed position.

• Journal of electromagnetic engineering and science
• /
• v.12 no.4
• /
• pp.260-270
• /
• 2012

This work aims to present a theoretical analysis of the electric and magnetic surface current densities of a circular microstrip antenna (CMSA) as a body of revolution. The rigorous analysis of these problems begins with the application of the equivalence principle, which introduces an unknown electric current density on the conducting surface and both unknown equivalent electric and magnetic surface current densities on the dielectric surface. These current densities satisfy the integral equations (IEs) obtained by canceling the tangential components of the electric field on the conducting surface and enforcing the continuity of the tangential components of the fields across the dielectric surface. The formulation of the radiation problems is based on the combined field integral equation. This formulation is coupled with the method of moments (MoMs) as a numerical solution for this equation. The numerical results of the electric and magnetic surface current densities on the outside boundary of a CMSA excited by $TM_{11^-}$ and $TM_{21^-}$ modes are presented. The radiation pattern is calculated numerically in the two principle planes for a CMSA and gives a good results compared with measured results published by other research workers.

• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.28A no.12
• /
• pp.12-17
• /
• 1991

In this paper, E-plane gap-coupled rectangular microstrip antennas with parasitic elements are analyzed. The mutual coupling between the radiating edges is represented as the voltage-dependent current source. The gap coupling between the patch and parasitic element is characterized with the REC(Radiating Edges-Coupling) model, and the conventional transmission line model is used to obtain the equivalent circuit of the antenna. The return loss of the rectangular microstrip antennas with short-and open-circuit parasitic elements are calculated and compared with the measured values. The theoretical values including the mutual coupling are more in agreement with the measured values than the calculated values without the mutual coupling.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.12 no.5
• /
• pp.827-836
• /
• 2001

The L-shaped strip is shown to be an attractive feed for the thick microstrip antenna (thickness around 10% of the operating wavelength). The L-strip incorporated with the radiating patch introduces a capacitance suppressing some of the inductance introduced by the strip itself. In this paper, a wideband microstrip patch antenna fed by L-strip for the PCS (1,750~1,850 MHz) and IMT-2000 (1,920~2,170 MHz) broad-band is presented. A two-element array fed by L-strip is also proposed. Both the antennas have stable radiation patterns across the passband. The impedance bandwidth is over 31% (VSWR < 1.5, 615 MHz) of the center frequency. Moreover, both the antennas have about 7 dBi average gain.