Design of a Low-Noise 24 GHz Receiver Using MMICs

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• Design of a Low-Noise 24 GHz Receiver Using MMICs

Eric Tollefson, Rose-Hulman Institute of
Technology
Faculty Advisor Dr. L. Wilson Pearson
Project Background
Results
Bias Conditions VDD0 V IDD0 mA VGG-1 V
The current receiver front-end, with NF7 dB _at_ 24
GHz(by Joel Simoneau)
Image courtesy of J. Simoneau
Bias Conditions VDD5 V IDD72 mA VGG-1 V
23.6-24.0 Ghz is a quiet band
Resonant frequencies of water vapor, with 24 GHz
marked
520 µm

• New amplifier
• Fujitsu FMM5701X
• 18-28 GHz
• 13.5 dB gain _at_ 24 GHz
• NF1.4 dB min _at_ 24 GHz
• Requires external bias and matching circuitry
• Difficult to perform out-of-circuit testing

Images courtesy of J. Simoneau

• Passive band is used for weather prediction using
  satellites
• Measuring man-made noise in the passive band and
  surrounding frequencies
• Need very low noise receiver for maximum
  sensitivity
• Prior design 7 dB noise figure
• Noise figure is dominated by the first stage
  amplifier (see equation below)
• New design will replace first amplifier stage to
  get a lower total noise figure
• Improvement should be about .6 dB over previous
  design

S-Parameter Measurements of prototype from
23.6-24.0 GHz (blue) and design values (green)
450 µm
Future Work
Image courtesy of Fujitsu

• Troubleshoot to obtain correctly working
  prototype
• Verify that matching design is correct using
  s-parameters
• Measure amplifier gain and noise figure
• Integrate into complete system, including DC bias
  circuitry
• Measure whole-system noise figure and gain
  parameters for comparison with previous design
• Take new noise measurements

New Design