Multiplexer Design For SATCOM Applications

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Multiplexer Design For SATCOM Applications

• Presented By Arpit Patel
• ME Electronics Communication (CSE)
• LD Engineering College

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Contents

• Function Of Multiplexers
• Overview of Designing of Dielectric resonant
  Filter
• Overview of Designing of Waveguide Filter
• Waveguide Manifold Designing
• Multiplexer design

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FUNCTION OF MULTIPLEXERS

• Channelizing the frequency (necessary due to
  non-linearity of TWTA)
• Power per carrier EIRP increased
• Division of received signals - I/P Multiplexers
  (IMUX)
• Recombining of amplified signals - O/P
  Multiplexers (OMUX)

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MULTIPATH EFFECT IN SATELLITE CHANNELS

• Channelization of received signals to minimize
  inter-modulation generation in high power
  amplifiers
• Incoming signal may take as many coherent paths
  as there are number of transponders
• Leakage through each path adds in coherent manner
  at the OMUX output
• Amplitude phase response of the channel changes
  due to leakage path
• Sensitive to difference in gain between adjacent
  transponders

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Example

• Ku-band INSAT-4CR Communication Payload
• Available bandwidth 480 MHz
• Number of transponders 12
• Available bandwidth / Transponder 40 MHz
• No. of TWTAs 12
• TWTA O/P Power 140 Watts

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Multiplexer
ANTENNA
Multiplexer
Manifold
Filter n
Filter 1
Filter 2
Channel-1
Channel-2
Channel-n
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• DIELECTRIC RESONATOR (DR) FILTER
• SINGLE MODE DR FILTERS

FULL WAVE RESPONSE OF 5-P DR FILTER (ANSOFT)
PHYSICAL STRUCTURE OF 5-P DR FILTER
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Designing of Waveguide Filter
COUPLING SCREW AT 450
TE11 MODE FIELD CONFIGURATION IN CIRCULAR
WAVEGUIDE
COUPLING ROUTING DIAGRAM FOR 6-P FILTER
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PHYSICAL STRUCTURE OF FILTER
EM SIMULATED RESPONSE OF S-BAND DOUBLY
TERMINATED FILTER
EM SIMULATED RESPONSE OF S-BAND SINGLY
TERMINATED FILTER
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MENIFOLD DESIGN
TOWARDS ANTENNA
SHORT
CHANNEL -2
CHANNEL -3
CHANNEL -1
3-CHANNEL MENIFOLD
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(a) Combline
(b) Herringbone
Common Configurations for Manifold Multiplexer
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• DESIGN OF HIGH POWER MUX
• Ku-BAND 12 CHANNEL MUX (EXAMPLE)

MECHANICAL LAYOUT OF Ku BAND MUX
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7-channel Ku-band Mux
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EM SIMULATED RESPONSE OF 7 channel Ku-Band
MULTIPLEXER
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Future work

• Achieve Sharp cutoff for a pass band
• Ratio of the Usable Bandwidth / Available
  Bandwidth is Utilization of the Frequency
  Spectrum is 90 because we have to include guard
  bands
• Use of Saw filters in Satellites to make them
  small

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References

• 1 C. Wang, K. A. Zaki, A. E. Atia and T. G.
  Dolan, Dielectric combline resonators and
  filter, IEEE Trans. Microwave Theory and Tech.,
  Vol. MTT-46, pp2501-2506, Dec. 1998.
• 2Http//www.ee.bilkent.edu.tr/microwave/program
  s/magnetic/mfilters/theory.htm
• 3. Temes, G.C. and Mitra, S.K., Modern Filter
  Theory and Design, Wiley, 1973

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THANK YOU