한국형발사체 2차 비행시험 발사대시스템 파라미터 측정 결과 분석

이송철(Songcheol Lee),문경록(Kyungrok Moon),안재철(Jaechel An),정일형(Ilhyung Jung),홍일희(Ilhee Hong) 한국추진공학회 2022 한국추진공학회 학술대회논문집 Vol.2022 No.11

Small-Size Low-Loss 28-GHz Body-Floated CMOS DPDT Switch Using Shared Matching Network

Lee, Wonho,Hong, Songcheol IEEE 2018 IEEE microwave and wireless components letters Vol.28 No.12

<P>A small-size low-loss double-pole double-throw switch using a shared matching network (SMN) for two I/O ports is presented in which redundant matching networks of I/O ports are combined into the simple SMN. This simplification allows it to have small-size and low-loss characteristics. The SMN is connected between the two inputs of the switch to resonate with the OFF-capacitances of the switch FETs, which is implemented with an inductor. Body-floated switch FETs are adopted for the switch, of which improvements are analyzed. The proposed switch is implemented in a 65-nm CMOS process with a series type. It operates in the range of 22–40 GHz, maintaining the return loss below −15 dB. It shows 1.3-dB insertion loss, 20-dB isolation, and IP<SUB>1 dB</SUB> of 6.2 dBm at 28 GHz. The insertion loss difference is measured to be less than 0.1 dB in the operating frequency. It occupies a core size of 0.022 mm<SUP>2</SUP>.</P>

A CMOS Power Amplifier With Integrated-Passive-Device Spiral-Shaped Directional Coupler for Mobile UHF RFID Reader

Sunbo Shim,Songcheol Hong IEEE 2011 IEEE transactions on microwave theory and techniqu Vol.59 No.11

<P>A CMOS power amplifier (PA) with a compact spiral-shaped directional coupler for a mobile UHF RF identification (RFID) reader is proposed here, and its output power combiner and the directional coupler are implemented using an integrated passive device process. The two-chip solution not only enables a CMOS PA to be highly efficient, but also allows the directional coupler and the power combiner to be mounted in a compact standard package. A polar transmitter is implemented using the CMOS PA with the directional coupler to verify the operation of the proposed configuration for a UHF RFID reader. Measurements indicate that the CMOS PA with the directional coupler transmits 27.3 dBm of output with 44.6% of power-added efficiency and that the implemented polar transmitter satisfies the required UHF RFID reader specifications.</P>

Design of a VHF/UHF/L-Band Low-Power Active Antenna for Mobile Handsets

Kyeongrae Cho,Songcheol Hong IEEE 2012 IEEE antennas and wireless propagation letters Vol.11 No.-

<P>A small triple-band receiving active antenna for VHF, UHF, and L-band broadcasting that can be used for mobile handsets is presented. This antenna consists of a small single passive helical antenna and a triple-band low noise amplifier (LNA). The design procedure of this antenna, in which the passive antenna shows very different impedances at each band, is also presented. Furthermore, it is demonstrated that the proposed configuration can be used as a triple-band receiving active antenna for VHF (174-216 MHz), UHF (470-806 MHz), and L-band (1450-1492 MHz).</P>

Differential Phase Doppler Radar With Collocated Multiple Receivers for Noncontact Vital Signal Detection

Han, Kawon,Hong, Songcheol Professional Technical Group on Microwace Theory a 2019 IEEE transactions on microwave theory and techniqu Vol.67 No.3

<P>A differential phase Doppler radar sensor with multiple receivers (RXs) to remotely detect human vital signals is proposed, which can reduce common motion artifacts as well as common noises to RXs. This is achieved by differentiating two-phase signals from a pair of collocated RXs. Random motions are decomposed into several kinds of motions with respect to the transmitted beam direction. Six differential phase signals are obtained from the four RX combinations, among which at least one pair can get vital signals with reduced common motion artifacts. A weighted-sum method is proposed to combine six differential signals effectively, which allows vital signals to be clearly detected even with large random body motions. A sensor is implemented with a commercially available 24-GHz radar front-end chip with one transmitter and four RXs to verify the differential phase radar concept. An experiment demonstrates that body motion noises are reduced by over 20 dB with the proposed differential phase radar with multiple RXs.</P>

A 2.4-GHz CMOS Common-Gate Combining Power Amplifier With Load Impedance Adaptor

Jin, Yoonsoo,Hong, Songcheol THE INSTITUTE OF ELECTRICAL ENGINEERS 2017 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS Vol.27 No.9

<P>A CMOS common-gate (CG) combining power amplifier is introduced, which has a simple load impedance adaptor. The CG stage of a cascode amplifier consists of a main amplifier with a load impedance adapter and an auxiliary amplifier with a phase compensator, which are biased for classes AB and C, respectively. The proposed configuration not only increases the efficiency of the power amplifier (PA) at back-off powers, but also increases the linearity at high output powers by canceling AM-AM and AM-PM nonlinearities of the main amplifier with those of the auxiliary amplifier. A load impedance adaptor can be used to match two different optimum load impedances of the main and auxiliary amplifiers simultaneously. A phase compensator is introduced to match the output phases of both amplifiers. It has a die size of 0.9 x 1.63 mm(2) operates at 2.484 GHz with a 3.3 V supply, which is implemented with the 0.18-mu m CMOS technology. It shows a linear output power of 22.1 dBm with a PAE of 32% for an 802.11 n signal at error vector magnitude (EVMs) of -25 dB, and it also shows apparent efficiency improvements at back-off powers.</P>

A Dual-Power-Mode Output Matching Network for Digitally Modulated CMOS Power Amplifier

Yumi Lee,Songcheol Hong IEEE 2013 IEEE transactions on microwave theory and techniqu Vol.61 No.4

<P>A dual-power-mode output matching network for a digitally modulated power amplifier (DMPA) to improve low power efficiency is proposed. The DMPA with output matching network is fully integrated using a 0.13- μm RF CMOS process. The matching network incorporates a switched transformer and capacitors. The switched transformer is proposed for tuning its inductance to have two power modes. It is designed to minimize losses due to parasitic components of the switch transistor. The DMPA has a 12-bit resolution to enable a wide digital transmit power control (TPC) range. The peak power is 29.3 dBm with 34% efficiency. The efficiency at 16 dBm is improved from 8% to 13% by using the output matching network. Simple static predistortion helps the DMPA reconstruct 27.9-dBm WCDMA signals at 1.95 GHz with 31% efficiency. The digital TPC range is 25 dB.</P>

A Transmitter or a Receiver Consisting of Two Strongly Coupled Resonators for Enhanced Resonant Coupling in Wireless Power Transfer

Dukju Ahn,Songcheol Hong Institute of Electrical and Electronics Engineers 2014 IEEE transactions on industrial electronics Vol. No.

<P>This paper proposes a novel resonator structure for efficiency and transferred power improvements: a transmitter (a receiver) that consists of two strongly coupled resonators. The two strongly coupled resonators are embedded within a transmitter device (a receiver device) and behave as a single resonator with enhanced performances. Unlike the conventional four-coil system, the first and the fourth resonators are also designed to have high loaded-Q and maximum cross couplings. Therefore, the first and the fourth resonators also take part in the coupled resonance with opposite-side resonators. This provides additional energy exchange path. The exact design guidelines are provided for each different resonance topology from analytical derivation. It is analyzed and experimentally demonstrated that the efficiency and the transferred power are increased by the proposed two-resonator technique. For a 30 cm × 25 cm parallel-resonant transmitter and an 18 cm × 16 cm parallel-resonant receiver at 13-cm distance, the efficiency and the transferred power with the proposed technique are 65.2% and 17.2 W, respectively, whereas those values without the proposed technique are only 37.3% and 6.2 W.</P>

Wireless Power Transfer Resonance Coupling Amplification by Load-Modulation Switching Controller

Dukju Ahn,Songcheol Hong Institute of Electrical and Electronics Engineers 2015 IEEE transactions on industrial electronics Vol. No.

<P>This paper proposes that transmitter-to-receiver resonator efficiency can be enhanced by the novel combination of resonator and switching controller at the receiver side. More specifically, the switching controller modulates the load resistance such that the receiver resonance is amplified. This increases the loaded-Q, reflected resistance, and, subsequently, overall efficiency and distance range. The efficiency and distance range are superior than resonator-only receivers, despite of losses from the switching controller itself. This breaks the common routine that typical switching converters only lower the power flow and efficiency when they are inserted in wireless power chain. Moreover, the scheme solves the common problem of load-variation-induced efficiency degradation. More specifically, if the present load value is deviated from optimal point, the proposed controller adjusts the effective load resistance to amplify the reflected resistance. The loaded-Q amplification is easily controlled simply by changing the duty ratio of switching controller. This is more feasible than traditional impedance transformation network whose control requires large array of capacitor-switch matrix or movement of coil position. The efficiencies with and without the switching-controlled resonance amplification are 60.2% and 51.7%, respectively, for a 20-W loading at 15-cm distance for a 20 cm × 16 cm receiver.</P>

A 1.83 GHz 28.5 dBm CMOS Power Up-Mixer

Ji-Seon Paek,Songcheol Hong IEEE 2009 IEEE microwave and wireless components letters Vol.19 No.6

<P>A power up-mixer is proposed in this letter. A merged CMOS linear power amplifier (PA) and mixer allows low current consumption and smaller chip size than a conventional integrated transmitter including a mixer and a CMOS linear PA. The chip is fabricated in a 0.18 mum CMOS process and in an integrated-passive-device. Measurements show a drain efficiency of 27% at 27.2 dBm of 1 dB compression point (P1dB) output power from 1.75 to 1.95 GHz. Power conversion gain is 26.4 dB and LO leakage is -43 dBc.</P>