Radar apparatus and control system

A radar apparatus that uses a frequency modulated continuous wave, the radar apparatus comprising:

• processing circuitry to:
• generate a random number sequence of one or more bits, and
• generate a local signal according to a bit value of each bit of the random number sequence;
• a transmitter to generate a transmit signal by frequency modulating a carrier wave with the local signal, and transmit the transmit signal;
• a mixer to obtain the transmit signal from the transmitter, combine the transmit signal with a receive signal received by a receiving antenna, and output a mixer output signal;
• and
• a control filter to accept, as input, the mixer output signal and allow the mixer output signal to pass through the control filter according to a control signal;
• the processing circuitry further to:
• obtain the random number sequence, determine, using the random number sequence, a passing condition of at least one of a passing time period and a passing frequency band of the control filter, and output a signal indicating the passing condition, as the control signal, to the control filter;
• and
• obtain the random number sequence, and determine whether there is an attack, based on the random number sequence and an output signal outputted by the control filter according to the control signal.