Radar device

A radar device that utilizes frequency modulation of a frequency modulated continuous wave type, the radar device comprising:

• a voltage-controlled oscillator to generate a high frequency signal that is frequency-modulated based on a triangular wave voltage signal;
• a transmission antenna to emit the high frequency signal into air;
• a receiving antenna to receive, as a reception signal, a reflected wave from a target object, of the high frequency signal;
• a mixer to generate a beat signal having a frequency equal to a frequency difference between the reception signal and the high frequency signal;
• an analog-to-digital converter to convert the beat signal generated by the mixer to a digital signal;
• a digital-to-analog converter to convert data of a triangular wave voltage signal that is a digital signal into an analog signal, and output the analog signal to the voltage-controlled oscillator;
• and
• a controller to calculate a distance from the target object and a relative velocity with respect to the target object, using the digital signal of the beat signal, and switch output between data of the triangular wave voltage signal corresponding to a first signal modulated in a first modulation scheme and data of the triangular wave voltage signal corresponding to a second signal modulated in a second modulation scheme within a same frame of scanning of the radar device, the first signal and the second signal using different bandwidths,
• wherein the controller includes a memory to store data of the triangular wave voltage signals such that an initial voltage of data of the triangular wave voltage signal corresponding to the second modulation scheme is caused to be equal to an initial voltage of data of the triangular wave voltage signal corresponding to the first modulation scheme at a time of switching from the first modulation scheme to the second modulation scheme within the same frame to perform modulation to eliminate a difference between initial transmission frequencies of the first signal and the second signal, and
• at the time of switching, the triangular wave voltage signal corresponding to the first modulation scheme and the triangular wave voltage signal corresponding to the second modulation scheme are separated by an interval of constant voltage.