1 Scope
This standard specifies the methods of measuring the frequency of diagnostic and monitoring ultrasonic equipment (hereinafter referred to as “the equipment”) within a frequency range of 0.5 MHz to 15 MHz.
This standard is applicable to all kinds of diagnostic and monitoring ultrasonic equipment working in continuous wave, quasi-continuous wave or pulse wave states. These equipment can be equipped with single chip emitting-receiving probe, double single chip emitting-receiving split probe, multi-chip quincunx probe, mechanical fan scanning probe, linear probe, convex array probe and phased array probe, etc.
2 Normative references
The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. For dated references, subsequent amendments (excluding corrections) to, or revisions of, any of these publications do not apply. However parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document applies.
GB/T 16540-1996 Acoustics - Measurement and characterisation of ultrasonic fields in the frequency range 0.5MHz to 15MHz - Hydrophone method (eqv IEC 61102:1991)
YY/T 0163-1994 Characteristics and calibration of hydrophones for medical ultrasonic fields
3 Terms and definitions
For the purpose of this standard, the following terms and definitions apply.
3.1
nominal acoustic-working frequency
ultrasonic working frequency of the tested equipment published by the manufacturing unit or supplier
3.2
acoustic-working frequency
actual ultrasonic-working frequency obtained from the analysis of the output signal by zero-crossing frequency method or frequency spectrum analysis method (see Figure 1) with the hydrophone placed at an appropriate position in the acoustic field, which is taken as the arithmetic average acoustic-working frequency in this standard
