Patent ID: 7429947
Filing Date: 2008-09-30
Classification: G01S

Abstract:
1. A radar apparatus comprising: a transmitter unit which radiates a transmitter signal; a plurality of antennas each of which receives a reflected wave produced by a reflection of said transmitter signal off an object; a first switch unit which connects output terminals of said plurality of antennas in sequence and one at a time to an input terminal; a downconverting unit which, by using a portion of said transmitter signal, downconverts a received signal input from said antenna connected to said input terminal of said first switch unit; a second switch unit which connects an output of said downconverting unit to a selected one of first to nth filter circuits; a digital signal processing unit inputting each output of said first to nth filter circuits to each of first to nth AD converters corresponding to the first to nth filter circuits, and applying prescribed processing to first to nth output signals output from said first to nth AD converters, and thereby detecting distance or relative velocity with respect to said object; and a signal characteristic checking unit which compares two output signals selected from among said first to nth output signals that were output based on said received signal received by a particular antenna selected from among said plurality of antennas, and thereby checks for differences between characteristics of first to nth receiver circuit systems respectively comprised of the filter circuit and the AD converter, based on changes in characteristics of said first to nth output signals, and corrects for any difference in the characteristic of each receiver circuit system; wherein said digital processing unit corrects said first to nth output signals with correction values, and detects said distance or relative velocity with respect to said object based on said corrected first to nth output signals.