Radar device and method of calculation of receive power in radar device

An electronic scan type radar device which uses a high resolution performance processing to estimate directions of arrival of radio waves, wherein powers of arrival waves received for targets are accurately calculated, that is, a vehicle-mounted radar device utilizing electronic scan which uses a predetermined angle estimation system to estimate directions of arrival of reflected waves, comprising finding mode vectors for angles calculated from the receive signals of the antennas, decomposing a vector of the receive signals into directions of the mode vectors, and defining the lengths of the decomposed vectors the receive powers of the reflected waves arriving from the targets. Due to this method, even if there are targets, it is possible to accurately calculate the powers of the arrival waves, whereby pairing is accurately performed, the precision of detection of targets is improved, and erroneous operation of a vehicle-mounted radar device utilizing electronic scans is prevented.