| 摘要 |
<p>A method for determining the level of a fluid in a tank including the steps: (i) synchronizing the firing signal and/or start signal from a synchronizer (101) to a pulser (103) and/or timer with the rising edge of a clock cycle; (ii) amplitude adjusting by a DAC/amplifier the electrical signals from the transducer (104); (iii) rectifying and filtering by FWR/LPF (107) the primary echo packets from the fluid surfaces, the tank's bottom, and the calibration reflectors (25) to form primary echo envelopes; (iv) digitizing the primary echo packets or primary echo envelopes from the fluid surfaces, the tank's bottom, and the calibration reflectors prior to their scanning by a site operating controller; and (v) (a) storing the TOF of the leading edge of each primary echo envelope from the fluid surfaces, the tank's bottom, and the submerged calibration reflectors; (b) threshold detecting a low gain adjusted signal; (c) threshold detecting a high gain adjusted signal; and (d) determining the fluid level.</p> |
