Method for measuring distances/speeds of plural targets and radar apparatus, capable of discriminating moving targets from stationary targets

摘要

The present invention discriminates between moving targets and stationary targets in order to measure distances and speeds of the targets without producing a false target. The invention transmits signals whose modulating frequencies ascend or descend to a target, and receives signals reflected from this target. A frequency spectrum of a beat signal of each target is detected during a modulating frequency ascent period and a modulating frequency descent period. The frequency spectrum of the modulating frequency ascent period and the frequency spectrum of the modulating frequency descent period are used to set a reference spectrum. The reference beat frequencies of either the moving targets or the stationary targets are detected based upon the reference spectrum. The beat frequencies of targets in the modulating frequency ascent and descent periods are used to form a combination seeking table, from which a component other than the reference beat frequencies of either the moving targets or the stationary targets are removed. The distances and speeds of the targets are calculated based upon the beat frequency components from the combination seeking means.