PIN Diode RF Switch for Mobile Satellite Antenna Providing Voice and Data Services

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PIN Diode RF Switch for Mobile Satellite Antenna
Providing Voice and Data Services
Sponsor Hughes Network Systems Mentor Ph.D.
Bill Whitmarsh
Third Presentation

• Group 1 Ricardo Murillo Paul Hsieh Tam Do
  Sean Yun

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Agenda

• Introduction
• Gantt Chart
• Explanation of New Design
• Shunt PIN Diode Switch
• Multi-Switch PIN Diode Model
• Summary

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Gantt Chart
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Design Procedure

• Design a low pass filter with 3dB cutoff
  frequency above highest operating
• frequency of 1665 MHz
• Insertion loss is chosen to be less than 0.5 dB
  in the pass band
• Input and output impedances of filter are scaled
  to match 50 ohms

• Diode is approximated as a capacitor in reverse
  bias
• Replace these capacitors with diodes that have
  similar reverse bias capacitances
• Replace inductor L1 with microstrip line

References Microwave Solid State Circuit
Design, Bahl and Bhartia Low Loss mm-Wave
Monolithic SP4Ts, L. M. Devlin, A. W. Dearn, G.
A. Pearson
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Transmission Line

• Transmission line terminating in short circuit
• Zin jZotan(Bl) where B (2p)/l is the
  propagation constant
• For l l/4, Zin goes to infinity (open circuit)

• Quarter wavelength transmission line terminated
  in load R_L
• Zin Zo2/R_L where Zo is the characteristic
  impedance of the line

Reference Microwave Engineering, David Pozar
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Shunt PIN Diode Switch
Antenna
50O Impedance
Satellite Modem
50O Impedance
50O Impedance
Receiver
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Multi-Switch PIN Diode Model
Satellite Modem
Antennas
Receiver
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Patch Antenna
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Summary
Accomplished Goals

• Re-evaluated design for PIN diode switch.
• Received PIN diodes from Skyworks.

Goals\Tasks for Week 5

• Design micro-strip. (Sean and Paul)
• Finalize schematic of PIN diode switch. (Tam and
  Ricardo)
• Begin schematic on PCB Express program.

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