An Improved Stepped-Frequency PMCW Waveform for Automotive Radar Applications

In phase-modulated continuous wave (PMCW) radar systems, fine range resolution typically requires high instantaneous bandwidths, necessitating fast-sampling analog-to-digital converters (ADCs). However, these ADCs are expensive and power-consuming. Consequently, due to their affordable hardware implementation, today's automotive radar systems still mainly employ analog frequency-modulated continuous wave (FMCW) waveforms. A larger bandwidth without requiring fast-sampling ADCs can also be synthesized by transmitting consecutive pulses in a coherent processing interval (CPI) at incremented carrier frequencies. To enable PMCW with low-data-rate ADCs, this paper proposes an improved stepped-frequency PMCW (SF-PMCW) waveform and evaluates its performance against a stepped-frequency FMCW (SF-FMCW) radar system in a simulated environment. The results indicate that the proposed SF- PMCW waveform can yield superior target detection capabilities with comparable system parameters.