김기운 교수

Highly linear receiver RF front-end adopting MOSFET transconductance linearization by linearly superposing several common-source FET transistors in parallel (multiple gated transistor, or MGTR), combined with some additional circuit techniques are reported. In MGTR circuitry, linearity is improved by using transconductance linearization which can be achieved by canceling the negative peak value of g/sub m/'' of the main transistor with the positive one in the auxiliary transistor having a differ

Mutual interference between automotive radar sensors is becoming a major concern due to the rapid increase of vehicles equipped with such systems. While there has been a plenty of studies on the interference of frequency modulated continuous wave (FMCW) radars, no work on chirp sequence (CS) radars has been reported in the literature in spite of their growing popularity in the automotive field. In this regard, this work presents an investigation of mutual interference for automotive CS radars. W

Ever since a 3b/cell (TLC) NAND Flash memory became the mainstream in nonvolatile memory market, a new demand for a 4b/cell (QLC) NAND flash memory has been emerging for low-cost applications. However, QLC has inherently much longer page program time than TLC because of 16-state programming within a limited program and erase (PE) window, as well as narrower V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sub> distributions. The longer page-pro

CMOS RF MMIC amplifiers are fabricated with linearization technique using multiple gated transistors. At 900 MHz, double and triple gated amplifiers show 2.5-4.5 dB larger figure of merit (linearity-DC power consumption), which means that only 1/2/spl sim/1/3 of DC power is needed to obtain the same OIP/sub 3/ value. Using Volterra series analysis and harmonic balance simulation, it is shown that the linearization technique with the 2nd harmonic termination can increase IIP/sub 3/ by amount of 1

We study human pose estimation in extremely low-light images. This task is challenging due to the difficulty of collecting real low-light images with accurate labels, and severely corrupted inputs that degrade prediction quality significantly. To address the first issue, we develop a ded-icated camera system and build a new dataset of real low-light images with accurate pose labels. Thanks to our camera system, each low-light image in our dataset is coupled with an aligned well-lit image, which

Metal nanotip photoemitters have proven to be versatile in fundamental nanoplasmonics research and applications, including, e.g., the generation of ultrafast electron pulses, the adiabatic focusing of plasmons, and as light-triggered electron sources for microscopy. Here, we report the generation of high energy photoelectrons (up to 160 eV) in photoemission from single-crystalline nanowire tips in few-cycle, 750-nm laser fields at peak intensities of (2-7.3) × 1012 W/cm2. Recording the carrier-e

The recursive least squares algorithm (RLS) using dichotomous coordinate descent (DCD) iterations, namely, RLS-DCD, is regarded to be well suited for hardware implementation because of its small computational complexity compared to the classical RLS algorithm. While this is true, yet another important aspect that ultimately determines its applicability for real-time applications with high sample rates, is its iteration bound. In this brief, we discuss this issue and propose a modified RLS-DCD al

A salient adaptive carrier recovery with a multi-order Digital Phase-Locked Loop (DPLL) based on Kalman filtering is presented in this paper. Using optimal loop gain sequence, that is Kalman gain sequence, for various optimization criteria, the proposed DPLL achieves fast phase acquisition and low phase jitter. The loop gain sequence optimized under the Least Squares (LS) criterion shows enough phase tracking capability under severe fading and can be used for mobile communication applications. F

RAW images are rarely shared mainly due to its exces-sive data size compared to their sRGB counterparts ob-tained by camera ISPs. Learning the forward and inverse processes of camera ISPs has been recently demonstrated, enabling physically-meaningful RAW-level image processing on input sRGB images. However, existing learning-based ISP methods fail to handle the large variations in the ISP processes with respect to camera parameters such as ISO and exposure time, and have limitations when used fo

An approach for visual question answering is described. The proposed network solves an open‐ended problem with candidate answer recommendation, which is generated solely from the given question. Then, the score from the proposed question‐aware prediction module and the score from candidate answer recommendation module are combined to determine the final composite score. The proposed approach uses the bag‐of‐words framework to understand questions, instead of a complex and neural‐network‐based mo

A simple yet efficient technique is proposed to improve the performance of distributed sorting based K-best detection. The proposed technique is to interleave partially sorted elements so as to reduce the distribution skew that is the major cause of performance degradation of distributed sorting. Experimental results show that the proposed interleaving almost fully recovers the degradation and makes the performance close to that of the original K-best detection.

When a node of a distributed storage system fails, it needs to be repaired quickly enough to maintain system integrity. While typical erasure codes can provide significant storage advantage over replication, they suffer from poor repair efficiency. Locally repairable codes (LRCs) tackle this issue by reducing the number of nodes participating in the repair process (locality), at the cost of reduced minimum distance. In this paper, we study the tradeoff characteristics between locality and minimu