Doppler frequency shift exhibits which of the following?

Doppler frequency shift exhibits which of the following?

• A. Aliasing
• B. Narrow bandwidth
• C. Spectral broadening
• D. Mirroring

Answer: (C)

Doppler frequency shift arises from motion between the source, the observer, or scatterers, which changes the observed frequency. If every scatterer moved at exactly the same speed, you’d see a single shifted line. But in real situations there is a range of velocities (thermal motion, turbulence, flow profiles), so each scatterer contributes a slightly different Doppler shift. Those many shifted components add together, broadening the spectrum around the shifted center frequency. That spread is known as spectral (or Doppler) broadening, which is why this option best describes what Doppler frequency shift exhibits. Aliasing would be a sampling artifact, not a fundamental feature of the Doppler effect; narrow bandwidth would imply less spread, and mirroring isn’t related to Doppler phenomena.

Doppler frequency shift arises from motion between the source, the observer, or scatterers, which changes the observed frequency. If every scatterer moved at exactly the same speed, you’d see a single shifted line. But in real situations there is a range of velocities (thermal motion, turbulence, flow profiles), so each scatterer contributes a slightly different Doppler shift. Those many shifted components add together, broadening the spectrum around the shifted center frequency. That spread is known as spectral (or Doppler) broadening, which is why this option best describes what Doppler frequency shift exhibits. Aliasing would be a sampling artifact, not a fundamental feature of the Doppler effect; narrow bandwidth would imply less spread, and mirroring isn’t related to Doppler phenomena.