Impacts on Automotive MIMO RADAR Performance due to Permittivity Variation of Bumper Material: Insights through Bi-directional Loss and Antenna Array Ambiguity Function

In this paper, the effect of car bumper permittivity variation on automotive MIMO RADAR antenna array is critically examined using metrics like bi-directional loss model and antenna array ambiguity function. First, a MIMO RADAR with two transmit and four receive antennas is designed and placed behind a simplified curved bumper CAD model. Next, the BLM as well as the AAAF for the antenna-bumper system is computed using the virtual array pattern approach. The proposed analysis provides quantitative insights into the effects on MIMO RADAR performance metrics like field-of-view, angular resolution and ambiguity in direction-of-arrival estimation, caused by real-life antenna-bumper interactions.