• Title, Summary, Keyword: RF Transmission

Search Result 637, Processing Time 0.046 seconds

Development of Liquid Stub and Phase Shifter

  • Wang, Son-Jong;Yoon, Jae-Sung;Hong, Bong-Guen
    • Nuclear Engineering and Technology
    • /
    • v.33 no.2
    • /
    • pp.201-208
    • /
    • 2001
  • The high power RF transmission line components are required for transmitting MW level RF power continuously in RF heating and current drive system which heat the plasma and produce plasma current in fusion reactor The liquid stub and phase shifter is proposed as the superior to the conventional stub and phase shifter. Experimental results show that they are reliable and easy to operate compared to the conventional stub and phase shifter. There is no distortion of reflected power during the raising of the liquid level. RF breakdown voltage is over 40kV. Temperature increment of the liquid is expected not to be severe. These results verify that the liquid stub and phase shifter can be used reliably in the high power continuous RF facilities.

  • PDF

Implementation of 2.45GHz RF Transceiver System of USN (USN용 2.45GHz RF Transceiver 시스템 구현)

  • Kim, Ji-Eun;Kim, Nae-Soo
    • Proceedings of the IEEK Conference
    • /
    • /
    • pp.135-136
    • /
    • 2007
  • 2.45 GHz RF Transceiver composed RF module and Digital module for USN(Ubiquitous Sensor Network) has been implemented in this paper. The proposed RF system is designed based on IEEE 802.15.4-2006 PHY standard which has a frequency range from $2.4{\sim}2.4835GHz$. In this transmitter chain, the output power is controlled form 0 to 30 dBm. In this receiver chain, less than 20 dB of NF was obtained.

  • PDF

The Development of the Data Error Inspection Algorithm for the Remote Sensing by Wireless Communication (원격계측을 위한 무선 통신 에러 검사 알고리즘 개발)

  • 김희식;김영일;설대연;남철
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.993-997
    • /
    • 2004
  • A data error inspection algorithm for wireless digital data communication was developed. Original data converted By wireless digital data error inspection algorithm. Wireless digital data is high possibility to get distortion and lose by noise and barrier on wireless. If the data check damaged and lost at receiver, can't make it clear and can't judge whether this data is right or not. Therefore, by wireless transmission data need the data error inspection algorithm in order to decrease the data distortion and lose and to monitoring the transmission data as real time. This study consists of RF station for wireless transmission, Water Level Meter station for water level measurement and Error inspection algorithm for error check of transmission data. This study is also that investigation and search for error inspection algorithm in order to wireless digital data transmission in condition of the least data's damage and lose. Designed transmitter and receiver with one - chip micro process to protect to swell the volume of circuit. Had designed RF transmitter - receiver station simply by means of ATMEL one - chip micro processing the systems. Used 10mW of the best RF power and 448MHz-449MHz on frequency band which is open to public touse free within the limited power.

  • PDF

Design and Performance Evaluation of M×M MIMO Transmission in ESPAR Antenna (ESPAR 안테나에서 M×M MIMO 송신방식의 설계와 성능 평가)

  • Bok, Junyeong;Lee, Seung Hwan;Ryu, Heung-Gyoon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.38A no.12
    • /
    • pp.1061-1068
    • /
    • 2013
  • In this paper, we propose a $M{\times}M$ beam-space multiple input multiple output (BS-MIMO) system using electronically steerable parasitic array radiator (ESPAR) antenna. Conventional MIMO method required multiple RF chains because it map the transmission signals onto multiple antennas. So, conventional MIMO system has high cost for design and high energy consumption at RF circuit. Also, It is difficult to use MIMO system in battery based mobile terminals with limited physical area. In order to solve these problems, BS-MIMO technique which map the data signal onto bases in beam space domain was proposed using ESPAR antenna with single RF chain. This paper, we design and analyze the performance of extended $M{\times}M$ BS-MIMO technique. Simulation results show that the proposed BS-MIMO system has similar BER performance compare to conventional MIMO scheme. Therefore, BS-MIMO system with single RF chain will has a low RF power consumption and low cost for RF hardware design as compared with conventional MIMO technique with multiple RF chains.

Dynamic Coverage Control to Improve Channel Utilization in IEEE 802.11 (IEEE 802.11에서 채널 이용율을 높이기 위한 동적 커버영역 제어)

  • 양덕용;이태진
    • Proceedings of the IEEK Conference
    • /
    • /
    • pp.195-199
    • /
    • 2003
  • BEE 802.11 Wireless LAN protocol uses fixed transmission power. It does not consider a power control mechanism based on the distance between the transmitter and the receiver in order to improve overall channel utilization. In home environment, where stations generally lie around an AP, the AP is subject to use transmission power more than it needs. And wireless LAN stations may require different minimal desired received power. If there are many adjacent BSSs in densely populated WLAN area, they might cause RF interference to one another. In this paper we focus on the improvement of aggregate utilization by mitigating RF interference among BSSs. We show that RF interference by APs can be reduced by controlling transmission power using Link Margin information. The reduced interference will then lead to the increased aggregate throughput which is efficient resource utilization.

  • PDF

A study on F8L10D-N LoRa RF Module for Drone Based live Broadcasting system

  • Mfitumukiza, Joseph;Mariappan, Vinayagam;Lee, Minwoo;Cho, Juphil;Cha, Jaesang
    • International Journal of Advanced Culture Technology
    • /
    • v.4 no.4
    • /
    • pp.1-5
    • /
    • 2016
  • In this paper, we present the study on the proposed design of a real-time transmission of a video from the drone to broadcasting station (OBVan) by using F8L10D-N LoRa Module. Nowadays, LoRa technology is proved to be the mass of low cost, long range machine-to-machine connectivity. Particularly in the field of broadcasting and communication system, F8L10D-N LoRa RF Module spread spectrum technology with long transmission distance and strong penetrative ability that is double stronger than traditional FSK as well as PSK modulation scheme.

Research and Implementation of Using RF wireless Power Transmission System for Wireless Sensor Nodes Battery-Charging Power Harvesting Module (RF 무선전력전송을 이용한 센서노드 배터리 충전용 전력획득모듈 연구 및 구현)

  • Jung, Won-Jae;Park, Jun-Seok
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.48 no.6
    • /
    • pp.34-42
    • /
    • 2011
  • With the progress of USN technology, fields to which wireless sensor node is applicable are increased under a condition that it holds a lot of problems to solve for betterment. One of the problems which acts as an obstacle to USN industry diffusion is the wireless sensor node battery exchange to their individual life cycle. Exchanging the battery of so many sensor nodes one by one requires a great deal of times and costs. Such problem is against the convenience supply -aim by applying USN technology. In this paper, using RF wireless power transmission system that power transmission / harvesting module from a distance of 5 m and the power of 10 dBm with a current of 1 mA or more for Sensor Nodes in lithium-polymer battery charging system tested and verified.

Performance Improvement of DS-CDMA Signal through MZ Modulator in Optical SCM Signal Transmission with Rake Receiver (광 SCM 전송방식에서 MZ 변조기를 통과한 DS-CDMA 신호의 레이크 수신기에 의한 성능개선)

  • 김회준;이도현;신성일;임명섭
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.14 no.11
    • /
    • pp.1113-1120
    • /
    • 2003
  • It is expected in the future that the demand of optical subcarrier multiplexing system, in which a number of small size base stations with only antenna and RF transmission are connected to central station using optical fiber, will be increased in the CDMA digital cellular mobile communication network. In this paper, in order to analysis the performance of optical SCM system fur CDMA RF signal transmission, MZ modulator is modelled as a non-linear transfer function with cubic operation. The performance degradation due to multipath signals and other user signals through MB modulator is analyzed and the performance is improved using the Rake receiver.

Influence of Deposition Pressure on Optical and Electrical Properties of ITO/Al/ITO Thin Films on PET by RF Magnetron Sputtering (RF magnetron sputter에 의한 PET기판상 ITO/Al/ITO 박막의 증착 압력이 광학적 전기적 특성에 미치는 영향)

  • Seo Jung-Eun;Kim Sang-Ho;Lee In-Seon;Kim Dong-Won
    • Journal of the Korean institute of surface engineering
    • /
    • v.38 no.2
    • /
    • pp.69-72
    • /
    • 2005
  • ITO-Al-ITO multi-layers were deposited at room temperature by RF magnetron sputtering on polyethylene terephthalate (PET). The films were deposited at various pressures of $8\times10^{-4},\;1\times10^{-3},\;4\times10^{-3},\;8\times10^{-3}\;and\;1\times10^{-2}$ Torr. A correlation between microstructure and electro-optical properties was studied. Films deposited? at low pressure have higher transmission, and lower reflectance and resistance than film deposited at high pressure. Sheet resistance, transmission, and reflectance were $141.6\Omega/\Box\;88\%\;and\;6.8\%$ resectively when the deposition pressure was $8\times10^{-4}$ torr, that was the optimum condition.

Study on the stabilisateur of information transmission in RF-CBTC train control system using the FHSS system (FHSS방식을 채용한 RF-CBTC 열차제어시스템 정보 전송의 안정화에 관한 연구)

  • Oh, Sea-Hwa;Jin, Zhe-Huan;Lee, Key-Seo
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.9 no.4
    • /
    • pp.455-468
    • /
    • 2014
  • This paper presents seamless hand off implementation suggesting algorithm and Measuring /testing at the tunnel environment in order to derive the ideal value of wireless data transmission in RF-CBTC train control system modeled by Shinbundang Operation System. In addition, it proposes the ideal value(-57dB) for reducing the re-transmission or frequency interference rate and demonstrates frequency optimization which enables highly reliable data communication in Train control system using wireless communications. Based on these result, Shinbundang phase 2 plan to apply to this system.