Which of the following is not a beam steering technique for a mechanical scan head?

• A. Rotating Wheel
• B. Oscillating Disc
• C. Phased Beam
• D. Oscillating Mirror

Answer: (C)

In mechanical scan heads, beam direction is changed by moving parts. Rotating wheels deflect the beam as the wheel rotates, an oscillating disc tilts the beam by wobbling a component, and an oscillating mirror redirects the beam by tilting the mirror. Phased beam, however, uses electronic timing across multiple elements to steer the beam without moving parts. By adjusting the phase of each element’s signal, the interference pattern changes so the beam points in a new direction electronically. That makes phased beam a different, electronic steering method rather than a mechanical one.