1. A distance-measuring sensor for detecting and determining the distance of objects in a monitored zone, the distance-measuring sensor comprising: a transmitter for transmitting transmitted pulses; a receiver for generating a received signal from the transmitted pulses remitted in the monitored zone; a first comparator unit for digitizing the received signal with reference to a first threshold; a control and evaluation unit which is configured to transmit a plurality of transmitted pulses via the transmitter, to collect the received signals thereupon generated by the receiver in a histogram and to determine a received time point from the histogram and thus to determine a measured value for the signal transit time from the sensor to the object; and a second comparator unit for digitizing the received signal with reference to a second threshold, wherein the first comparator unit, the second comparator unit and the control and evaluation unit are configured to acquire three digital states of a respective section of the received signal with reference to the first threshold and to the second threshold and to weight the contributions of the respective section to the histogram in dependence on the digital state, wherein the two thresholds are placed on both sides of a zero line of the received signal, and wherein the digital state between the two thresholds corresponds to a noise band to be suppressed.