| 摘要 |
A precision acoustic source that is capable of producing acoustic radiation having peak and average power levels that are independently and simultaneously adjustable. The apparatus comprises an acoustic transducer and drive means for producing a drive signal comprising a series of drive pulses to the transducer, such that the transducer produces acoustic radiation having selected peak and average power levels. The drive means comprises means for establishing a series of fixed-length clock cycles, means for generating a series of trigger signals, pulse generating means responsive to each trigger signal to produce a selected number of standard pulses, an amplifier for generating a drive pulse in response to each standard pulse. The amplifier adjusts the amplitude of each drive pulse such that the peak power of the acoustic radiation is equal to the selected peak power level. Each trigger signal occurs either R or S clock cycles after the preceding trigger signal, R and S being positive integers. The apparatus further comprises means for determining R and S such that the average power of the acoustic radiation is equal to the selected average power level at the selected peak power level. In a preferred embodiment, the number S is equal to R+1.
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