Matthias Steinhauer

Millimeter-Wave-Radar Sensor Based on a Transceiver Array for Automotive Applications

This paper describes a new radar sensor architecture comprising an array of transceiver modules. Target applications of the sensor are automotive driver assistance systems. In conjunction with a monolithic integration of each transceiver, the concept offers the possibility for a cost-effective realization of digital-beamforming radar sensors at millimeter-wave frequencies. A modulation sequence is investigated based on simultaneously transmitted frequency-modulated continuous-wave signals, which are separated by frequency multiplexing. Appropriate signal processing for the estimation of range, speed, and azimuth angle in multiple object situations is presented. Experimental results with an eight-channel radar sensor in the 76-77-GHz frequency band are presented, which demonstrate the feasibility of the proposed architecture and show the performance of the modulation sequence and signal processing.

Defining acceptable phase-modulated nonlinearities in 77 GHz FMCW automotive radar systems

A method to determine the maximum allowable frequency error of a PLL generated FMCW radar slope is presented. Using the side lobe suppression as a metric, the maximum frequency error in a linear FMCW slope is defined based on the used window function. With higher distortion frequency a higher side lobe suppression is required. It is shown that for fast chirp sequence modulation in the absence of any additional counter measures, the minimum allowable frequency error is on the order of a few kHz, which is nearly impossible to be achieved by commercial radar systems.