A5038500265- Radio Frequency Integrated Circuit Design
- Microwave Engineering and Waveguides
- Advanced Power Amplifier Design
- Photonic and Optical Devices
- Millimeter-Wave Propagation and Modeling
- Antenna Design and Analysis
- Advancements in PLL and VCO Technologies
- Electromagnetic Compatibility and Noise Suppression
- Molecular Junctions and Nanostructures
- Semiconductor Lasers and Optical Devices
- Analog and Mixed-Signal Circuit Design
- 3D IC and TSV technologies
- Advanced biosensing and bioanalysis techniques
- Conducting polymers and applications
- Wireless Power Transfer Systems
- Full-Duplex Wireless Communications
- Semiconductor materials and devices
- GaN-based semiconductor devices and materials
- Advancements in Semiconductor Devices and Circuit Design
- Semiconductor Quantum Structures and Devices
- Electrochemical sensors and biosensors
- Graphene research and applications
- Advanced Antenna and Metasurface Technologies
- Luminescence and Fluorescent Materials
- Molecular Sensors and Ion Detection
Korea Advanced Institute of Science and Technology
2015-2024
Korea Research Institute of Bioscience and Biotechnology
2016-2024
Korea Bio Polytechnic College
2023
Daegu-Gyeongbuk Medical Innovation Foundation
2021-2022
University of Houston
2016-2022
Hanyang University
2022
Chonnam National University Hospital
2017-2020
Chonnam National University
2016-2020
Gwangju University
2017-2020
Graduate School USA
2017-2020
A low-power and high data-rate fully integrated 60-GHz on-off keying (OOK) transceiver for short-range wireless communication is demonstrated. The consists of a switch, transmitter, receiver uses OOK modulation compact design. With highly efficient Tx, high-speed modulator/demodulator, wideband characteristic, the has capability. Implemented in 90-nm CMOS technology, transmitter consume 31 36 mW at 10.7 Gb/s occupy an active footprint 0.15 0.29 mm <sup...
Spin–torque nano–oscillators (STNOs) have outstanding advantages of a high degree compactness, high–frequency tunability and good compatibility with the standard complementary metal–oxide–semiconductor process, which offer prospects for future wireless communication. There as yet been no reports on communication using STNOs, since STNOs also notable disadvantages such lower output power poorer spectral purity in comparison those LC voltage–controlled oscillators. Here we show that is...
In the brain and central nervous system, dopamine plays a crucial role as neurotransmitter or local chemical messenger for interneuronal communication. Dopamine is associated with renal, hormonal, cardiovascular systems. Additionally, dysfunction known to cause serious illnesses, such Parkinson's disease Alzheimer's disease. Therefore, detection essential medical diagnosis prevention requires novel strategy high sensitivity selectivity rapid response. Herein, we present human receptor...
Abstract Fatal pathogenic organisms have been detected by various point‐of‐care tests (PoCTs) in clinical samples. PoCTs based on portable electrical devices are able to detect simple and rapid method. Although PoCT show ultra sensitivity when detecting pathogens standard samples, their industrialization has limited due low reproducibility, sensitivity, specificity, resulting from nonspecific binding issues media. In this research, a perpendicular N‐heterocyclic carbene self‐assembled...
A facile route to graphene/polymer hydrogel nanofibers was developed. An aqueous dispersion of graphene (containing >40% bilayer flakes) stabilized by a functionalized water-soluble polymer with phenyl side chains successfully electrospun yield nanofibers. Subsequent vapor-phase cross-linking the produced graphene-embedded (GHNFs). Interestingly, GHNFs showed chemical sensitivity cationic dyes methylene blue (MB) and crystal violet (CV) in phase. The adsorption capacities were as high 0.43...
Abstract Organophosphates are powerful inhibitors of acetylcholinesterase, which is critical to nerve function. Despite continuous research for detecting the highly toxic organophosphates, a new and improved methodology still needed. Herein we demonstrate simple-to-fabricate chemiresistive gas sensors using conducting-polymer polypyrrole (PPy) nanotube transducers, chemically specific capable recognizing sub-ppb concentrations (ca. 0.5 ppb) dimethyl methylphosphonate (DMMP), simulant agent...
This paper reports a 60-GHz four-element beam-tapering phased-array transmitter with lower sidelobe level (SLL). The array factor and the error vector magnitude (EVM) were calculated to explain low characteristic of nonuniform amplitude emphasize importance phase compensation, respectively. phase-compensated radio frequency (RF) variable gain amplifiers (VGAs) proposed compensate variance shifters and, simultaneously, excite each element. VGA improves relative by 2° OP1dB 2.4 dB within...
A personal communications service/wide-band code division multiple access (PCS/W-CDMA) dual-band monolithic microwave integrated circuit (MMIC) power amplifier with a single-chip MMIC and single-path output matching network is demonstrated by adopting newly proposed on-chip linearizer. The linearizer composed of the base-emitter diode an active bias transistor capacitor to provide RF short at base node transistor. enhances linearity effectively for both PCS W-CDMA bands no additional DC...
A novel series-fed E-shaped patch antenna array with copolarized parasitic patches for enhanced aperture efficiency at 60-GHz unlicensed wideband applications is proposed. The additional radiation from the inserted between improves gain flatness remarkably as well and efficiency, because of offset resonant frequency. four-array presents 0.8-dB over whole 57–66 GHz band, 14.5 dBi peak gain, 63.6% while that without shows 1.4-dB flatness, 13.4 49.2% any change in size, <inline-formula...
Abstract Hydrogen sulfide (H 2 S) is an important biological messenger, but few biologically-compatible methods are available for its detection in aqueous solution. Herein, we report a highly water-soluble naphthalimide-based fluorescent probe ( L 1 ), which versatile building unit that absorbs and emits at long wavelengths selective hydrogen over cysteine, glutathione other reactive sulfur, nitrogen oxygen species We describe turn-on probes based on azide group reduction the fluorogenic...
This paper presents a low-profile, highly isolated, wideband, U-shaped slot-coupled dual-polarized patch antenna for the 60 GHz frequency band. The proposed exhibits broadband characteristics that entirely cover industrial, scientific, and medical (ISM) band, by forming additional resonance at coupled slot. port isolation is improved up to 38.6 dB via circulating current in feed line of port, which caused reverse placement between distributions circular phenomenon occurs resonant point...
Fluorescent polydopamine nanoparticles (FPNPs) are prepared via the ethylenediamine (EDA)-induced degradation of as-prepared non-fluorescent (PDA) and used for targeted bioimaging. The reductive treatment PDA in presence EDA yields fluorescent precipitates, inspiring us to seek various biological approaches preparing FPNPs with excellent optical biocompatible properties. Moreover, we firstly found that selectively label neuromast hair cells lateral line zebrafish, their applications as a...
Abstract In this study, ultrasensitive and precise detection of a representative brain hormone, dopamine (DA), was demonstrated using functional conducting polymer nanotubes modified with aptamers. A high-performance aptasensor composed interdigitated microelectrodes (IMEs), carboxylated polypyrrole (CPNTs) DA-specific The biosensors were constructed by sequential conjugation CPNTs aptamer molecules on the IMEs, substrate integrated into liquid-ion gating system surrounded pH 7.4 buffer as...
This study presents the design and analysis of a 60-GHz low-power active vector-sum phase shifter with 5-bit resolution. An impedance-invariant variable gain amplifier (VGA) is proposed applied to vector modulator. The VGA not only demonstrates low impedance variations during control but also high linearity under supply voltage. Moreover, it reduces gain/phase error in modulation. In addition, transformer-based current-reuse technique adopted enhance phased array channel while consuming dc...
In this paper, an analysis of a power amplifier manipulated using second harmonic (PA-2HM) is described remarkable correlation between the fundamental and impedances. The output loading condition, made up optimum impedance mapped to conditional reactance, allows us achieve high-efficiency (PA) with simple matching circuit. For analysis, voltage current waveforms are modeled in terms their order extend efficiency. Specific PA-2HM cases, inverse Class-F Class-J modes, analyzed different...
This paper presents a low-loss and high Tx-to-Rx isolation single-pole double-throw (SPDT) millimeter-wave switch for true time delay applications. The is designed based on matching-network double-shunt transistors with quarter-wavelength transmission lines. insertion loss characteristics of the switches are analyzed revealing that optimization transistor size receiver side transmitter can enhance performance low loss. Implemented in 90-nm CMOS, achieves measured 1.9 39 dB at 60 GHz,...
A D-band gain-boosted current-bleeding down-conversion mixer is presented in this letter using 65 nm CMOS technology. The proposed down- conversion uses a technique to improve the gain for low power chip communication with local oscillator (LO) power. Broadband Marchand baluns were used transform single-ended signal differential at RF and LO port measurement. According experimental results, had measured of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML"...
This article presents a high data rate, high-efficiency 60-GHz on-off keying (OOK) CMOS transmitter and receiver. The consists of voltage-controlled oscillator (VCO) modulator. receiver low-noise amplifier, detector, limiting amplifier (LA) has compact design. An analysis the isolation modulator bandwidth LA reveals that proposed transformer (TF) between VCO can improve isolation, feedforward capacitor enhance bandwidth. Implemented in 65-nm technology, consume dc powers 12.1 21 mW,...
A novel quantitative design method is proposed herein for a 120-GHz 8-stage broadband amplifier using the stagger tuning technique. The pole frequencies of unit amplifiers are determined by parasitic capacitors and size matching inductors, resonance peaks formed at frequency. We technique two different frequencies, where an inductance four stages chosen to match frequency lower (f <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">L</sub> ) other...