Author: Fathy, A.E.
Paper Title Page
WEP274 Broadband Antenna Matching Network Design and Application for RF Plasma Ion Source 1990
 
  • K.R. Shin
    ORNL RAD, Oak Ridge, Tennessee, USA
  • A.E. Fathy
    University of Tennessee, Knoxville, Tennessee, USA
  • Y.W. Kang, M.F. Piller
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: This work was supported by SNS through UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. DOE.
The RF ion source at Spallation Neutron Source has been upgraded to meet higher beam power requirement. One important subsystem for efficient operation of the ion source is the 2MHz RF impedance matching network. The real part of the antenna impedance is very small and is affected by plasma density for 2MHz operating frequency. Previous impedance matching network for the antenna has limited tuning capability to cover this potential variation of the antenna impedance since it employed a single tuning element and an impedance transformer. A new matching network with two tunable capacitors has been built and tested. This network can allow precision matching and increase the tunable range without using a transformer. A 5-element broadband matching network also has been designed, built and tested. The 5-element network allows wide band matching up to 50 kHz bandwidth from the resonance center of 2 MHz. The design procedure, simulation and test results are presented.