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EM Wave Source

Re-radiated EM field ???. EM Wave Source. Object. reflected traveling wave. u niform traveling wave. Dipole Antenna. Generator. Transmission Line. free space wave. Continuous Energy Density (Standing Wave). Reflective Parabaloid. Power Density i ncreased in this

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EM Wave Source

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  1. Re-radiated EM field ??? EM Wave Source Object

  2. reflected traveling wave uniform traveling wave Dipole Antenna Generator Transmission Line free space wave Continuous Energy Density (Standing Wave)

  3. Reflective Parabaloid Power Density increased in this region due to reflection from parabaloid. Increase in Power Density in a given direction is called GAIN, . Power Density decreased in this region due to reflection from parabaloid. EM Wave Source

  4. Aperture (Antenna) Receiver (Rx) Detector Object Transmitter(Tx) Signal Generator Bistatic System

  5. Aperture (Antenna) Receiver (Rx) Detector Signal +Noise (1) Signal preconditioning to enable detection (change frequency, amplitude, etc.) Signal post-conditioning to enable detection (sampling and averaging) Electronic Noise (2)

  6. Aperture (Antenna) Receiver (Rx) Detector Circulator or Mixer STIMULATED Signal +Noise (1) Signal Generator Transmitter(Tx) Monostatic System

  7. Radar Basics: Pulses and Range Gates Transmitted Pulse Noiseless Receiver Ln Pr Time

  8. Signals and Noise Transmitted Pulse Observed Signal (target echo plus noise) Ln Pr Time

  9. Signal Averaging and Detection Transmitted Pulse Observed Signal plus noise After Signal Averaging (target echo plus noise) Ln Pr Time

  10. The Radar “Bright” Band

  11. Multiple “Bright” Bands

  12. Steradians A Radian "cuts out" a length of a circle's circumference equal to the radius. A Steradian*"cuts out" an area of a sphere equal to (radius)2. *The name steradian is made up from the Greek stereos for "solid" and radian. The SI Unit abbreviation is "sr". Sphere vsSteradian The surface area of a sphere is 4πr2. The surface area of a steradian is just r2. So a sphere measures 4π steradians, or about 12.57 steradians. Likewise a steradian is 1/12.57, or about 8% of a sphere.

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