Design and Simulations of Low Loss Single Disk RF Window


  • Shakir Ullah PINSTECH, Nilore, Islamabad
  • M. Ayub PINSTECH, Nilore, Islamabad
  • N. Aftab PINSTECH, Nilore, Islamabad
  • A. Qayyum PINSTECH, Nilore, Islamabad



This paper describe three simple designs of pillbox type S-band RF window for 2.5 MW peak power operation. In these designs alumina ceramic disk is used as RF transmitting medium, which is brazed with pill-box copper to create vacuum seal. Three different fabrication configurations of RF window are simulated using CST Microwave Studio. The simulation results for one of the designs are quite promising. At the working frequency of 2.998 GHz, the return loss S11 and transmission loss S21 are -72.75 dB and S21 is -0.009 respectively. The power loss at window is just 5.2 W, indicating that forced cooling of window is not required. PACS: 87.50.Jk; 84.40.Ba

Author Biographies

Shakir Ullah, PINSTECH, Nilore, Islamabad

Physics Division

M. Ayub, PINSTECH, Nilore, Islamabad

LINAC Project

N. Aftab, PINSTECH, Nilore, Islamabad

LINAC Project

A. Qayyum, PINSTECH, Nilore, Islamabad

Physics Division


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How to Cite

S. Ullah, M. Ayub, N. Aftab, and A. Qayyum, “Design and Simulations of Low Loss Single Disk RF Window”, The Nucleus, vol. 53, no. 4, pp. 221–224, Aug. 2017.