Evaluation concept for distance measuring processes

A process for determining the distance between a distance sensor and an object, wherein an electrical pulse signal with a predetermined first frequency (f1) is directed to one transmitter of the distance sensor, the transmitter transmits upon the occurrence of each electrical pulse a wave pulse, the wave pulses are reflected off the object, and a receiver of the distance sensor receives the reflected wave pulses and puts out an analog electrical incoming signal, characterized by the steps of:

• continuously scanning the analog electrical incoming signal by an A/D converter at a second frequency (f2) with f2>f1, converting the scanned electrical incoming signal into a digital signal Z(t), and evaluating the digital signal Z(t), for the purpose of determining a distance value (D), by:
• a) evaluating the digital signal Z(t), received with respect to a plurality of n wave pulses, wherein n is an integral number (n>1), the evaluating step further including the steps of:
• a1) breaking down the digital signal Z(t) (13) into signal sequences Z1(t), . . . , Zn(t) which are in n temporal order;
• a2) forming a mean value via the n signal sequences, and calculating a mean digital signal <Z(t)>;
• and
• a3) using the mean digital signal <Z(t)> for determining a first wave pulse propagation time (T1);
• b) k-fold repeating step a) for determining total k wave pulse propagation times (T1, T2, . . . , Tk), wherein k is an integral number with k>1;
• c) calculating a mean wave pulse propagations time T (T1+T2+ . . . +Tk)/k;
• d) calculating the distance value (D) in accordance with D=v*T/2, wherein v is the propagation speed of the wave pulses.