A5055572770- Microwave Engineering and Waveguides
- Millimeter-Wave Propagation and Modeling
- Antenna Design and Analysis
- Advanced Antenna and Metasurface Technologies
- Advanced Materials and Mechanics
- Advanced MIMO Systems Optimization
- Telecommunications and Broadcasting Technologies
- Satellite Communication Systems
- Advanced Adaptive Filtering Techniques
- Liquid Crystal Research Advancements
- Antenna Design and Optimization
- Radio Frequency Integrated Circuit Design
- Energy Harvesting in Wireless Networks
- Advanced Photonic Communication Systems
Korea Advanced Institute of Science and Technology
2021-2024
This article presents a signal generator and digital beamforming receiver (DBR) with high phase control resolution beam resolution, respectively. The is designed based on direct synthesizer (DDS) lock loop (PLL). In the DDS–PLL generator, conventional divider in PLL replaced mixer, comb doubler to utilize of DDS (14 bit, 0.022°) as it synchronize entire system. DBR, output signals generators are used second local oscillator (LO) signal, technique implemented through change LO signals. Also,...
A hybrid multibeamforming receiver for low Earth orbit (LEO) satellite communication in the Ku-band is designed and tested. The proposed implemented with eight channels to enable multibeam control. receiver, including both analog digital beamforming structures, capable of reception using techniques simultaneously or selectively. Analog by employing a local oscillator phase shifter direct synthesis phase-locked loop (PLL) structures. In beamforming, software-defined radio can control signal...
Abstract Liquid crystal (LC)‐based radio‐frequency (RF) tunable antennas garner attention because of their compact size and minimal heat generation. Exploiting the LC's property to alter RF permittivity depending on its alignment, voltage‐induced orientational switching enables frequency modulation radiated wave. To ensure dependable antenna performance, precise control initial LC alignment is crucial, which conventionally achieved by polyimide (PI) coating followed rubbing process...
5G communication promises fast and large data stream which requires higher capacity of a cellular wireless network. A could be achieved with wider bandwidth network densification, but they are expensive approaches. Instead, upgrading the higher-order Multiple Input Output (MIMO) antenna system polarization diversity can inexpensively escalate peak rate for capacity. We present 4x4 MIMO scheme utilizing reuse using 4 to reform from current state art dual scheme. Polarizations (vertical,...
Interest in millimeter-wave(mm-wave) communication technology is increasing.The mm-wave band signal has a short wavelength but wide bandwidth, which useful for communication.However, it strong linearity and high free-space path loss.To overcome this, beamforming required.Beamforming of electrical tilting beam without mechanical motor.If applied to the system, can be various fields such as mobile well vehicle radar.In this paper, transmitter at 28GHz designed.After synchronization between...
Several millimeter wave antenna design studies are being conducted using the electrically variable performance of LCs.For RLSA design, characteristics linear array elements can be controlled by electrical bias LC.In this study, LC is used to implement tunable polarization radiation pattern antenna.The amplitude element calculated holographic theory and investigated.