Patent ID: 6956521

Claim:
A radar device, comprising: a transmitting means for transmitting an electromagnetic wave to a target object; a receiving means for receiving the electromagnetic wave that is transmitted from said transmitting means and reflected by the target object; a mixing means for mixing an output of said transmitting means and an input of said receiving means to generate a beat signal; a low-pass filter that allows a signal having a frequency component that is equal to or lower than a given frequency among the beat signals outputted from said mixing means to pass there through; an A/D converting means for sampling an output signal of said low pass filter to convert the sampling signal into a digital signal; a high-speed Fourier transforming means for subjecting the sampling signal that is sampled by said A/D converting means and converted into the digital signal to high-speed Fourier transformation; an aliasing discriminating/correcting means for discriminating a signal having a frequency component where aliasing occurs from the high-speed Fourier transformation result by said high-speed Fourier transformation processing means and for correcting the signal where aliasing occurs to a signal of a normal frequency component having no aliasing to obtain a distance and relative velocity data of the object on the basis of the corrected signal or the signal where no aliasing occurs; and a target object selecting means for selecting necessary data from the distance and relative velocity data of the object which are obtained by said aliasing discriminating/correcting means, wherein said aliasing discriminating/correcting means discriminates a normal distance and relative velocity data where no aliasing occurs from said candidates on the basis of a change in a frequency component of the high-speed Fourier transformation result with time when there are a plurality of candidates of the distance and relative velocity data of the object which are obtained from the high-speed Fourier transformation result.