A5080735730- Radio Frequency Integrated Circuit Design
- Microwave Engineering and Waveguides
- Terahertz technology and applications
- Photonic and Optical Devices
- Acoustic Wave Resonator Technologies
- Millimeter-Wave Propagation and Modeling
- Superconducting and THz Device Technology
- Advancements in PLL and VCO Technologies
- Semiconductor Quantum Structures and Devices
- Antenna Design and Analysis
- UAV Applications and Optimization
- Cooperative Communication and Network Coding
- Advanced MIMO Systems Optimization
- Advanced Power Amplifier Design
- Energy Harvesting in Wireless Networks
- Wireless Networks and Protocols
- GaN-based semiconductor devices and materials
- Full-Duplex Wireless Communications
- Radio Wave Propagation Studies
- Mobile Ad Hoc Networks
- Wireless Communication Networks Research
- Advanced MEMS and NEMS Technologies
- Semiconductor materials and devices
- Satellite Communication Systems
- Spectroscopy and Laser Applications
Seoul National University
2003-2025
Chosun University
2020-2024
Oklahoma State University
2019-2023
Changwon National University
2023
University of Glasgow
2022
Oklahoma State University Oklahoma City
2019-2022
The University of Texas at Dallas
2012-2020
Analog Devices (United States)
2016-2020
Korea University
2019
Korea Institute of Ocean Science and Technology
2017
Abstract Driven by advances in signal processing and multiuser detection (MUD) technologies, it has become possible for a wireless node to simultaneously receive multiple signals from other transmitters. In order take full advantage of MUD multi-packet reception (MPR) capable networks, is highly desirable make the compound transmitters more separable on its constellation at receiver coordinating both transmit power level carrier phase offsets this article, we propose feedback-based...
In the past year, fifth-generation (5G) wireless technology has seen dramatic growth, spurred on by continuing demand for faster data communications with lower latency. At same time, many researchers argue that 5G will be inadequate in a short given explosive growth of machine connectivity, such as Internet-of-Things (IoT). This prompted to question what comes after 5G. The obvious answer is sixth-generation (6G), however, substance 6G still very much undefined, leaving imagination terms...
Recent advances in signal processing have demonstrated in-band full-duplex capability at WiFi ranges. In addition to simultaneous two-way exchange between two nodes, access points can potentially support uplink and downlink flows. However, the atomic three-node topology, which allows downlink, leads inter-client interference. this paper, we propose a random-access medium control protocol using distributed power manage interference wireless networks with full-duplex-capable that serve...
CMOS IC technology has become an affordable means for implementing capable systems operating at 300 GHz and above. circuits have been used to generate a signal up 1.3 THz detect both amplitude phase of signals 1.2 THz, ~10 THz. Additionally, transmitter receiver ~300 electronic smelling using rotational spectroscopy, 30-Gb/s 300-GHz QPSK data communication with -6-dBm output power, 820 imaging array fabricated in reported. These results, along the circuit performance literature, link...
Electromagnetic waves in the millimeter- and sub-millimeter-wave frequency ranges are used fast-scan rotational spectroscopy to detect gas molecules measure their concentrations [1]. This technique can be for indoor air quality monitoring, detection of toxic leaks, breath analyses monitoring bodily conditions many others. paper reports a 210-to-305GHz receiver (RX) front-end spectrometer that achieves SSB noise figure (NF) 13.9 19dB by incorporating an on-chip antenna with reflector formed...
A quadrature LC-VCO incorporating passive coupling and broadband harmonic combining for frequency multiplication by 4, NMOS switched variable inductors is fabricated in 65 nm bulk CMOS to generate signals at 85 127 GHz. The bypasses the need a on-chip bias-T, while reducing power consumption, phase noise, theoretical conversion loss 4th order generation 3 dB over linear superposition. 39% tuning range least 4x higher than other implementations with center 90 At consumption of 30–45 mW from...
A 300-GHz 30-Gbps QPSK transmitter is demonstrated in 65-nm CMOS. The consists of an on-chip multi-mode modulator, injection locked quadrature oscillator, a 40-GHz bandwidth power amplifier with constant gain and group delay, 4X frequency multiplier chain to generate 165-GHz LO signal for double balanced up-conversion mixer that generates the output at 300 GHz. without equalization consumes 180mW energy efficiency 6 pJ/bit.
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> This paper presents the design, fabrication, and measurement results for a novel non-contact-type radio-frequency (RF) microelectromechanical systems switch 24-GHz radar applications. The proposed switches are free from unavoidable microwelding stiction problems in other contact types, which turn guarantee high reliability long lifetime. developed is capacitive shunt type using variation of...
This paper presents a new type of antenna fabricated by micromachining technology for mechanical beam steering with two degrees freedom motion. A V-band two-dimensional beam-steering was designed and on single high-resistivity silicon substrate using microelectromechanical systems technologies. is driven magnetic force to overcome the limit electrostatic actuation, polymer-based hinge structure used increase maximum scanning angle as much 40/spl deg/. Simulation result validating concept...
A beam-forming antenna module is demonstrated using an integrated CMOS beam-former chip and a simple two-metal layer printed circuit board at <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$V$</tex></formula> -band. The integrates absorptive single-pole four-throw switch together with 4 Notation="TeX">$\,\times\,$</tex></formula> Butler matrix 0.13- Notation="TeX">$\mu{\hbox {m}}$</tex></formula>...
This brief presents an active second-harmonic injection technique to improve the efficiency and bandwidth for high-efficiency power amplifiers (PAs). An optimum third-harmonic termination condition was examined higher after using a multiharmonic load-pull simulation. It determined that is same as of inverse class-F PA. Based on this result, PA with optimized designed center frequency 1 GHz main amplifier. The overall system requires auxiliary amplifier diplexer between PAs. implemented 10-W...
A 200-280 GHz RF front-end of transmitter is demonstrated in 65-nm CMOS. Saturated EIRP greater than -5dBm over a frequency range 60GHz. When the input power -20dBm, -10dBm for most range, and achieves 3-dB 6-dB bandwidths 24% 33%. The was integrated with fractional-N synthesizer to form operating at 208-255GHz -18 -11dBm. CMOS receiver are used rotational spectroscopy detect ethanol human breath.
A 160-310 GHz frequency doubler for rotational spectroscopy with a driver amplifier is demonstrated in 65-nm bulk CMOS process. At 0-dBm input power, the measured output power (Pout) varies from 3 to -8 dBm. The wide operating range attributed bandwidth and matching structure based on broadband open short leading >40dB difference between fundamental second harmonic at output. doubler-amplifier combination has comparable larger than 200-300 COTS GaAs modules.
The performance of CMOS transmitters and receivers operating at the submillimeter electromagnetic wave frequencies have sufficiently improved for use in active transmission reflection-mode imaging applications that potential broad deployment utilization. Imaging integrated circuits to be large area support a high number pixels along with digital backend processing circuits. For volume may eventually included automobiles, smartphones, laptops, tablets, others, manufacturing capacity ICs is...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> An accurate scalable small-signal RF CMOS model applicable to high frequencies is developed using 3-D electromagnetic (EM)-based extraction of parasitic elements. Due multimetal layers, vertical interconnects, substrate loss and substrate-contact rings, the extrinsic network field-effect transistor (FET) more complicated than GaAs FETs does not follow simple scaling rules. In this work, we have...
A broadband watt-level stacked-FET power amplifier (PA) has been developed using 0.15 μm GaAs pHEMT's. triple-stacked FET structure is used as a unit cell to combine RF voltage swings achieve high output and broad bandwidth at the same time. Special care taken solve thermal instability problems of cells for applications well optimize subsequent combiner bandwidth. The fabricated PA shows peak 33.7 dBm with added efficiency (PAE) 29.5% frequency 18 GHz, higher than 32 from 10 21 GHz....
A 410-GHz imager consisting of a 4 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> sub-harmonic mixer formed with an anti-parallel diode-connected NMOS transistor pair, and on-chip antenna 4.4-dB simulated gain is demonstrated in 65-nm CMOS. At −1.6-dBm power delivered to the LO input bond pad, achieves 16.8-dB voltage conversion loss 34.1-dB DSB noise figure. When bandwidth 1 kHz, sensitivity −110 dBm, which 30 dB better than...
Recent advances of devices and circuits have made CMOS (Complementary Metal Oxide Semiconductor) integrated technology an alternative for realizing capable affordable THz systems. Coherent detection up to 410 GHz incoherent 10 as well almost fully receiver working from 225–280 been demonstrated using CMOS. Despite the fact that f <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</inf> NMOS transistors has peaked around 320 GHz, it should be...
A 180-GHz minimum shift keying (MSK) receiver (RX) using a phase-locked loop (PLL), which self-synchronizes the carrier frequency, is demonstrated. The mixer-first RX fabricated in 65-nm CMOS process. double-balanced anti-parallel-diode-pair sub-harmonic mixer performs phase detection, reducing frequency of local oscillator (LO) by half. Tunable zeros realized series inductors are used to improve stability and increase data rate handling capability. Without external LO synchronization,...
Micromachined reflection-type phase shifters with small size and low loss for V-band communication systems are described. Two- three-bit reflection type were designed, fabricated, measured. The micromachined air-gap overlay coupler the direct contact series switches employed to implement shift reduce an insertion loss. can be obtained by changing length of open-ended stubs using cascaded MEMS switches. fabricated two-bit shifter has a measured 0/spl deg/, 41.5/spl 84.3/spl 128.7/spl deg/...
A pHEMT broadband image rejection receiver with an ratio (IRR) more than 20 dB from 54 GHz to 66 is presented using varactor tuning topology. Tunable varactors connected in shunt between RF coupler and mixers are used control the phase amplitude of two signals. It offers IRR improvement 3.1 ∼ 21.4 cost gain degradation below 1.1 except for 65 GHz. To best authors' knowledge, this work shows performance V-band receivers. At 61 GHz, circuit achieves 18.3 conversion (C.G) a 49.3 IRR. noise...
A 560-GHz RF front-end employing MOS symmetric varactor (SVAR) subharmonic mixers achieves a minimum SSB noise figure (NF) of 35 dB in the 4th order mixing (SHM) mode which is 5-7 lower than that SiGe HBT mixers. The fabricated 65-nm CMOS also 45-dB NF for 6 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> SHM at RF=810 GHz and 60-dB 10 RF=1.2 THz. Use SVAR's mixer first 1.2-THz highest among silicon coherent front-ends.