Radar device

A radar device comprising:

• a transmitter configured to, each time a preset measurement period corresponding to one cycle elapses, repeatedly transmit a radar wave whose frequency changes with time, every preset repetition period for a preset number of repetitions;
• a repetition period setter configured to change the repetition period each time the measurement period elapses;
• an object detector configured to receive the radar wave reflected from an object and thereby detect at least a relative velocity of a reflecting object which is the object that reflected the radar wave, as an observed velocity;
• and
• a hypothesis selector configured to select one of a first hypothesis, a second hypothesis, and a third hypothesis, based on velocity-accuracy posterior distributions that are posterior distributions relating to accuracies of the relative velocity after a preset number of distribution calculations, one for each cycle,
• the first hypothesis assuming that the observed velocity is an aliased relative velocity when the relative velocity is higher than an upper limit of an observable velocity range set based on the repetition period,
• the second hypothesis assuming that the observed velocity is an unaliased relative velocity, and
• the third hypothesis assuming that the observed velocity is an aliased relative velocity when the relative velocity is below a lower limit of the observable velocity range,
• the velocity-accuracy posterior distributions being respectively calculated for the first hypothesis, the second hypothesis, and the third hypothesis from velocity-accuracy prior distributions that are prior distributions relating to accuracies of the relative velocity, and a detection result of the observed velocities for the preset number of distribution calculations.