Which term describes the two-way travel time of a pulse?

Which term describes the two-way travel time of a pulse?

• A. Go-return time
• B. Time of flight
• C. Wavelength
• D. Pulse duration

Answer: (A)

Round-trip travel time is the duration from when a pulse is emitted to when its echo is received after bouncing off a reflector. This go-return interval is the measure that captures the two-way journey of the pulse. In practice, depth or distance is inferred from this round-trip time because the pulse traverses to the target and back, so the depth is proportional to half of the go-return time times the propagation speed. The other terms describe different properties: wavelength is how far the wave travels in one cycle, and pulse duration is how long the pulse lasts itself, not how long it takes to travel out and back. Time of flight is a synonymous idea in other contexts, but in this material the go-return time specifically denotes the two-way travel time.

Round-trip travel time is the duration from when a pulse is emitted to when its echo is received after bouncing off a reflector. This go-return interval is the measure that captures the two-way journey of the pulse. In practice, depth or distance is inferred from this round-trip time because the pulse traverses to the target and back, so the depth is proportional to half of the go-return time times the propagation speed. The other terms describe different properties: wavelength is how far the wave travels in one cycle, and pulse duration is how long the pulse lasts itself, not how long it takes to travel out and back. Time of flight is a synonymous idea in other contexts, but in this material the go-return time specifically denotes the two-way travel time.