Pulse repetition frequency

Pulse repetition frequency (PRF) indicates the number of ultrasound pulses emitted by the transducer over a designated period of time. It is typically measured as cycles per second or hertz (Hz). In medical ultrasound the typically used range of PRF varies between 1 and 10 kHz .

A number of artifacts are directly influenced by the pulse repetition frequency, e.g. increasing it diminishes the aliasing artifact commonly encountered during color and spectral Doppler imaging, while decreasing it facilitates e.g. the display of the useful twinkling artifact occurring behind stones and calcifications .