Range-Doppler Circulating LFM for Automotive MIMO Radars

A novel MIMO multiplexing scheme suitable for linearly frequency modulated (LFM) radars is proposed. Simultaneous utilization of multiple TX channels is achieved by applying per channel a small frequency offsets in both slow-time and fast-time. It provides a MIMO multiplexing scheme with no degradation of resolution in either range or Doppler, preserving the maximum range and unambiguous Doppler velocity of a single TX operation and satisfying the high dynamic range requirements. Moreover, the proposed technique allows utilization of a high-pass filter in the RX front for spillover rejection to limit the required dynamic range of the an analog-to digital (ADC) and exploits a low-cost FFT-based signal processing.