Wireless Communications and Radar for the New Millennium

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Wireless Communications and Radar for the New
Millennium

• Steve Lohmeier

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Personal Background

• Born and raised in Kansas City area
• Received B.S.E.E. from Kansas State University
• Received M.S. and Ph.D. from University of
  Massachusetts working on radar remote sensing
  problems (6 years)
• Worked on air and missile defense radars in
  Huntsville, AL (4 years)
• Currently on faculty at University of Kansas (1
  year)

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Research Interests

• General
• Antennas
• Propagation
• Sensor systems
• Specific
• Digital beamforming and adaptive array processing
  (smart antennas)
• Ultra-wideband radios and radar
• Bistatic scattering from natural surfaces
  (clutter) and multipath interactions
• Radar remote sensing

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Examples of Relevant Experience

• Adaptive/smart antennas
• RF propagation studies
• Ultra-wideband radar project to improve railway
  safety

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Adaptive Antenna Arrays
Main Lobe in Direction of Desired Signal

• Adaptive processing techniques originally
  implemented in speech processing and sonar
  applications
• Migrated to radar and wireless fields
• Teaching course in spring on adaptive antenna
  arrays based on experience with air-defense
  radars, but focusing more on wireless application
• Applicable to PCS, wireless local loops, etc.

Nulls in Directions of Cochannel Interferers
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RF Propagation Studies
Measurement Geometry
Receive

• Involved in a program with MIT Lincoln Lab to
  characterize bistatic scattering from terrain for
  use in multipath models
• Involved in many other programs to characterize
  all facets of the RF propagation environment
  (attenuation, clutter, multipath, interference,
  etc.)
• Applicable to future generation PCS wireless
  local loop design, indoor wireless network
  design, etc.

Transmit
Isorange contours
Dual polarization receiving system enclosed in
radome
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Improving Railway Safety Using Four Quadrant
Gates Controlled by Ultra-wideband Radar
No Detection
Crossing Island
Detection

• Four-quadrant crossing controlled by two entrance
  and two exit gates
• Exit gates are raised if vehicle is detected in
  entirely or partially within crossing island

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Motion and Change Detection
Radar 1
Zone 1
Zone 2
Radar 2

• Radar range profile is constantly compared to its
  previous version. If a sufficient change in the
  profile occurs a vehicle detection is declared.

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UWB Radar Transceiver
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Conclusions
Research partnerships
(particularly ones that are funded)
yield hard work, innovation,
enthusiasm, satisfaction,
and students trained and experienced in wireless
and radar technologies.