Does the transducer produce ultrasound waves continuously?

  • The transducer alternates through phases of generating and receiving ultrasound waves
  • The ‘Transmission Phase’ is the period of wave generation:
    • Usually very brief (0.5–3 μs)
  • Followed by a ‘Receiver Phase’ for wave detection:
    • Much longer (up to 1 ms) than the transmission phase
    • Allows echoes from a range of depths to be detected
  • The combined duration of the transmission and receiver phases is the pulse repetition period:
    • Determines the frame rate of an ultrasound generated image
    • Shallower depths allows for a shortened receiver phase and thus a higher frame rate