Distance measuring device

A distance measuring apparatus which radiates a radio wave, receives a reflected wave from an object under measurement, and detects the object under measurement, said distance measuring apparatus comprising:

• transmitting means for continuously transmitting a first frequency signal for a predetermined time or more, continuously transmitting a second frequency signal having a predetermined frequency difference from the first frequency for a predetermined time or more, and transmitting a signal having a frequency difference of an integer multiple equal to or larger than twice said predetermined frequency difference from the first frequency over signals at N frequencies, where N is an integer equal to or larger than one, said means having a first time region in which said first frequency signal and said second frequency signal are alternately transmitted over time, and a second time region in which said first frequency signal through an (N+2)th frequency signal are respectively transmitted alternately over time;
• receiving means for measuring a Doppler frequency of the reflected wave from said object under measurement at each of the respective transmission frequencies of said first frequency, second frequency, and N frequencies;
• and
• detection processing means for separating a plurality of objects under measurement to detect said object under measurement.