• Title/Summary/Keyword: S-band Switch

Search Result 51, Processing Time 0.024 seconds

Miniaturization Development of Transmit/Receive Module using a 10W MEMS switch (10W급 MEMS 스위치를 이용한 송수신모듈 소형화 개발)

  • Yi, Hui-min;Jun, Byoung-chul;Lee, Bok-hyung
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.20 no.12
    • /
    • pp.2417-2424
    • /
    • 2016
  • Small size and light weight is very important for components used in radar mounted platform such as airborne radar. Recently, the active phased array radar is developed as an array of antennas for thousands of transmit/receive modules to be used as a multi-function radar that can detect and track targets. In this case, the size and weight of the transmit/receive modules are critical factor for developing the radar. In this paper, we developed a compact transmit/receive module using the 10W RF MEMS switch domestically localizing and reduced the circuit area to about 86.5% compared to using a circulator. The developed module satisfies not only electrical requirements but also MIL-STD's environmental specifications. So it can be used in a military device. It can be used at adaptive tunable receivers, reconfigurable smart active antennas and wide band beam electrical steering antennas.

A multistandard CMOS mixer using switched inductor (스위칭 인덕터를 이용한 다중 표준용 CMOS 주파수 변환기)

  • Yoo, Sang-Sun;Yoo, Hyung-Joun
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.44 no.3 s.357
    • /
    • pp.78-84
    • /
    • 2007
  • A multistandard direct-conversion mixer for WCDMA, Wibro, and 802.11a/b/g is designed in 0.18 um CMOS technology To support multistandard and to reduce the chip area the switched inductor is used as the matching method. This switched inductor matching network selects the mixer's operation frequency band by turning on or off the switch transistor. Since the performances of mixer and operation frequency can be affected by the parasitic of switch transistor the mixer should be designed with the optimized size of switch to minimize parasitic effects. Proposed mixer is able to achieve return loss less than -13 dB in $2.1\sim2.5GHz$ and $5.1\sim5.9GHz$ bands with the suitable performance to meet requirements of WCDMA, WiBro, and 802.11a/b/g.

A Study on Operation of Man-Machine Interface for Tractor 3-point Hitch (트랙터 3점 히치의 인간-기계 인터페이스 동작에 관한 연구)

  • Lee, S.S.;Lee, C.H.;Lee, J.Y.;Mun, J.H.
    • Journal of Biosystems Engineering
    • /
    • v.32 no.5
    • /
    • pp.284-291
    • /
    • 2007
  • This study was to investigate performance of position, basic controls and additional control for man-machine interface on a 3-point hitch of a tractor. The developed additional control was one-touchup, backup, turnup, liftarm limited, PTO on/off and an external control. As a result of experiment, maximum steady state error of response system was lower than $0.8^{\circ}$ and this result showed the function operated normally because the dead band of system set was ${\pm}1^{\circ}$. There was no abnormal situation by switch operation and sensor signal during the performance test. The results of experiment showed the characteristics of the response was sufficient to be used as the position and additional control system for tractors.

Pulse 2 kW RF Limiter at S-band (S-대역 펄스 2 kW RF 리미터)

  • Jeong, Myung-Deuk
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.23 no.7
    • /
    • pp.791-796
    • /
    • 2012
  • A RF limiter is a component to protect the receiver front end from undesired signal. A RF limiter is a key component whose output is constant level for all inputs above a critical value. A RF limiter use a diode to pass signals of low power while attenuating those above some threshold. A RF limiter for receiver protection in modern radar systems is playing a vital role in order to meet challenges of new interference threats and complicated electromagnetic environments. This paper proposed a new circuit for high power RF limiter whose structure is the combination of the PIN diode and Limit diode. PIN diode take a use of its isolation characteristics which act as a switch does. A 2 kW RF limiter with 200 us pulse width at S-band was developed. It shows good agreements between estimated value and measured results.

Energetics of adsorptions on fcc(111) and binary system; An application of the modified embedded atom method

  • Hy. Shin;J. Seo;Kim, J.S.
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 1999.07a
    • /
    • pp.188-188
    • /
    • 1999
  • The embedded atom method (EAM) of Daw and Baskes as a semiempirical method, has been successfully applied to the fcc or nearly filled d-band transition metals due to its computational feasibility and its methodological simplicity. Then Baskes modified the EAM (MEAM) to include directional bonding and applied it to metals, semiconductors, and diatomic gases, all of which have different types of bondings. Here, we present a detailed study of the energetics of adsorption on the fcc(111) surfaces and binary system within the framework of MEAM. In adsorption on fcc(111) surfaces, there are two energetically favored sites, so called, fcc site and hcp site, which may trigger stacking fault in the growth of films and might switch growth mode between 3D growth and layer by layer growth. We scrutinized the role of the hcp sites, which would offer dynamic growth pathways although the dynamics are not yet clear within the limited experimental resolution. Featuring these transient motions in the atomic level should contribute to the understanding the growth mechanisms on fcc(111) surface. And we also applied MEAM for initial stage energetics at the Cr coverage of sub- monolayer on W(110). We hope that recently observed extraordinary growth behavior at the Cr coverage of 0.7 monolayer, self- organized nano-scale lines, can be resolved in this MEAM binary system calculation.

  • PDF

Real time control special quality research for $CO_2$ laser's output change rate stability for accumulation style surgical operation rehabilitation of ventriculus that use Photosensor (Photosensor를 이용한 재활 치료형을 위한 $CO_2$ laser 의 출력변동율 안정을 위한 실시간 제어특성 연구)

  • Kim, Whi-Young
    • Proceedings of the IEEK Conference
    • /
    • 2006.06a
    • /
    • pp.1015-1016
    • /
    • 2006
  • The important parameters deciding the fluctuation of Accumulation style surgical operation of ventriculus laser beam are smoothing capacitor, frequency and he characteristics of laser resonator. In this thesis, we control the fluctuation of medical $CO_2C$ laser in realtime by changing Duty-Ratio of IGBT and switching frequency with fixed the smoothing capacitor to improve the fluctuation of laser beam. We detect the light on laser resonator using a CdS photo sensor to improve ripple factor of laser beam and feedback fluctuated signals refined by a band pass filter into the control circuit to stabilize fluctuation actively. There is much to be desired in the realtime controlling technique of the light on Accumulation style surgical operation of ventriculus laser discharge tube in electrical signal. We propose switching control technique with microprocessor and photo sensing technique by controlling switch devices optimum operation and feedback signals detected by a photo sensor into the laser power supply in order to improve ripple factor of the $CO_2$ laser beam.

  • PDF

A Study on the Refarming Plan of the Low Frequency Bands according to the Transition from Analogue to Digital TV (디지털TV 전환에 따른 저대역 주파수 회수/재배치 방안 연구)

  • Yu, Hyeon-Yong
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.19 no.12
    • /
    • pp.1470-1481
    • /
    • 2008
  • A demand for spectrum resources, especially in the low frequency bands, is ever increasing with the development of mobile telecommunications and so is their economic value as other national resources. Also, development in mobile broadband require more bandwidth with excellent propagation characteristics, such as those frequencies in the 700/800/900 MHz bands. As a way to enhance the economic efficiency of using spectrum resources, many countries including the U.S., the U.K. and Japan, have recently focused on the refarming plan of the low frequency bands according to the transition from analogue to digital TV. By the way, as a result of WRC-07, those parts of the band $698{\sim}960\;MHz$ in Region 2 and the band $790{\sim}960\;MHz$ in Regions 1 and 3 which are allocated to the mobile service on a primary basis are identified for use by administrations wishing to implement International Mobile Telecommunications (IMT). Therefore, after analogue to digital television switchover, some administrations may decide to use all or parts of the band $698{\sim}806/862\;MHz$ for other services to which the band is allocated on a primary basis, in particular the mobile service for the implementation of IMT, while in other countries the broadcasting service will continue to operate in that band. And to conclude, bands already identified for IMT-2000 will also be able to be used for IMT. This work will help establish a policy direction for spectrum refarming in the low frequency bands in Korea(Rep. of).

A Study on the Implementation of Power Line Modem for Remote Control Using DSP (DSP를 이용한 원격 제어용 전력선 모뎀 구현에 관한 연구)

  • Kim Su Nam;Kang Dong Wook;Kim Ki Doo;Yoo Hyeon Joong
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.29 no.10C
    • /
    • pp.1433-1443
    • /
    • 2004
  • The power line modem proposed in this paper transmits the remote control signal using CSK(Code Shift Keying) and DS/SS method. The CSK technique provides the increased capacity of transmission and robustness towards noise. Besides, the DS/SS technique provides protection against narrow-band Gaussian interference and multi-path interference. The modem supports full-duplex communication using FDD(Frequency Division Duplex) and the modem structure for forward link is same with that for reverse link. To switch each sub-controlled unit smoothly, 4/$\pi$-DQPSK is adopted for noncoherent demodulation. The PN code for spreading spectrum seues to divide each group which consists of sub-controlled units and Walsh code is used for the M-ary CSK technique. Each block is designed and verified with TMS320C5402 DSP. We show the superiority of the proposed method by analyzing numerically the system performance for the factors of the DS/SS and CSK method ullder additive white Gaussian noise and PBI.

Design of the Actuator of Shaft Sliding Type for an Optical Pick-up to Switch an Objective Lens (대물렌즈 전환식 축습동형 광학픽업용 엑츄에이터 설계)

  • Choi, Young-Suk
    • Journal of the Korean Institute of Telematics and Electronics T
    • /
    • v.36T no.2
    • /
    • pp.32-41
    • /
    • 1999
  • The design method that the structure of double actuators of read-only or read-writable DVD optical pick-up of high density can be compact into the structure of one actuator, is proposed. The designed actuator has the structure of the shaft sliding type in which the moving part can be rotated about the shaft accord to a used optical disc and an objective lens can be switched, and is suspended with magnetic spring. In this actuator, Coulomb's friction is used as damping force and the moving part is designed by finite element method so that the second natural vibration mode can not occur within the servo band. The mock-up of the actuator designed in this paper is made, and its dynamic characteristics is measured and estimated.

  • PDF

A Study of the Intelligent Connection of Intrusion prevention System against Hacker Attack (해커의 공격에 대한 지능적 연계 침입방지시스템의 연구)

  • Park Dea-Woo;Lim Seung-In
    • Journal of the Korea Society of Computer and Information
    • /
    • v.11 no.2 s.40
    • /
    • pp.351-360
    • /
    • 2006
  • Proposed security system attacks it, and detect it, and a filter generation, a business to be prompt of interception filtering dates at attack information public information. inner IPS to attack detour setting and a traffic band security, different connection security system, and be attack packet interceptions and service and port interception setting. Exchange new security rule and packet filtering for switch type implementation through dynamic reset memory by real time, and deal with a packet. The attack detection about DDoS, SQL Stammer, Bug bear, Opeserv worm etc. of the 2.5 Gbs which was an attack of a hacker consisted in network performance experiment by real time. Packet by attacks of a hacker was cut off, and ensured the normal inside and external network resources besides the packets which were normal by the results of active renewal.

  • PDF