Range resolution in FMCW radars

A radar apparatus comprising:

• a local oscillator configured to generate a first ramp segment and a second ramp segment, a slope of the first ramp segment and a slope of the second ramp segment are equal and positive, and wherein, the first ramp segment and the second ramp segment each comprising a start frequency, a first frequency and a second frequency, and wherein the first frequency of the second ramp segment is equal to or greater than the second frequency of the first ramp segment;
• a transmit antenna unit coupled to the local oscillator and configured to transmit the first ramp segment and the second ramp segment;
• a receive antenna unit configured to receive a first received signal and a second received signal, wherein the first ramp segment and the second ramp segment are scattered by one or more obstacles to generate the first received signal and the second received signal respectively;
• a receiver front-end coupled to the receive antenna unit and configured to amplify the first received signal and the second received signal;
• a mixer coupled to the receiver front-end and configured to mix the first ramp segment and the first received signal to generate a first IF (intermediate frequency) signal and configured to mix the second ramp segment and the second received signal to generate a second IF signal;
• an analog to digital converter (ADC) coupled to the mixer and configured to sample the first IF signal to generate a first valid data and configured to sample the second IF signal to generate a second valid data;
• and
• a digital signal processor (DSP) coupled to the ADC and configured to process a data formed from the first valid data and the second valid data;
• wherein the ADC is configured to sample the first IF signal only from a time instant when the first ramp segment is at the first frequency to a time instant when the first ramp segment is at the second frequency and configured to sample the second IF signal only from a time instant when the second ramp segment is at the first frequency to a time instant when the second ramp segment is at the second frequency.