A ranging apparatus includes a reference pulse generator generating a reference pulse having a first frequency at a first point in time of transmitting a ranging signal from a first device; a delay pulse generator generating a delay pulse signal having a second frequency at a second point in time of receiving the a response signal transmitted from the second device in response to the ranging signal; an overlap detector detecting a third point in time that the reference and delay pulses overlap each other; a counter counting one of the reference and delay pulses until the third point; and a distance calculator calculating an amount of time from the first point to the second point by applying the first and second frequencies, and a count value of the counter and calculating the distance between the first device and the second device by using the amount of time.