Random forming of the monitoring zone of ultrasound measurement and control apparatuses by adapted control of the sensitivity response of the ultrasound receiver

摘要

The intensity of ultrasound signals which are processed in conjunction with ultrasound propagation time measurement apparatuses reduces in accordance with a non-linear function with increasing propagation time. According to the invention, a control signal of any desired function is produced such that any desired gain function can be produced in the receiver amplifier as a function of time. The sensitivity of the receiver can thus be adapted in freely definable zones such that the desired gain ratios exist within this zone.