METHOD AND APPARATUS FOR RANGE FINDING

摘要

High-resolution range finding of high accuracy is carried out at low cost in a short time using a carrier wave modulated to a PN code. A carrier wave modulated with a first PN code at a predetermined frequency is transmitted to a target, and the reflected wave from the target is received. A first burst signal is derived from the correlation between the first PN code and a second PN code having the same code as the first PN code and a slightly different frequency, while a second burst signal is derived from the correlation between the received carrier wave and the second PN code. The distance to the target is determined in accordance with the difference in phase between the first and second burst signals and the difference in phase between the first and second burst signals that have been integrated.