Distance measuring apparatus and method using impulse correlation

A distance measuring apparatus comprising:

• a digital-to-time conversion (DTC) generator unit configured to generate DTC signals, the DTC signals having edges delayed to define time segments in units of a pre-designated time interval from a starting time point at which an impulse signal is emitted;
• a template generator unit configured to generate template signals consecutively in a pre-designated number within the time segments in response to the DTC signals, the template signals having a same waveform as the impulse signal;
• a coarse time determiner unit configured to determine a time segment in which a delayed signal is received by calculating correlations with the consecutively generated template signals, when the delayed signal is received after a delay as the emitted impulse signal is reflected off an object;
• a fine time measurer unit configured to determine a time at which the delayed signal is received within the time segment determined at the coarse time determiner unit from results of calculating correlations between a plurality of template signals within the determined time segment and the delayed signal;
• and
• a distance calculator unit configured to calculate a total delay duration of the delayed signal from the determined time segment and the time at which the delayed signal is received within the time segment and calculate a distance to a measurement target object from the calculated delay duration,
• wherein the coarse time determiner unit calculates correlations between the plurality of template signals generated consecutively in each defined time segment and the delayed signal and determines a time segment for which the calculated correlation values are greater than or equal to a pre-designated threshold value,
• wherein the fine time measurer unit determines the time at which the delayed signal is received by applying I/Q modulation to each of the plurality of template signals within the determined time segment to obtain a plurality of I template signals and a plurality of Q template signals and calculating correlations between the plurality of I template signals and the plurality of Q template signals and the delayed signal.