FMCW multiple-input multiple-output radar with iterative adaptive beamforming

• Published in: IET radar, sonar & navigation Vol. 12; no. 11; pp. 1187 - 1195
• Main Authors: Eckhardt, Johannes M, Joram, Niko, Figueroa, Adrian, Lindner, Bastian, Ellinger, Frank
• Format: Journal Article
• Language: English
• Published: The Institution of Engineering and Technology 01.11.2018
• Subjects: array signal processing; bandwidth 100 MHz; collocated antennas; continuous wave multiple‐input multiple‐output radar system; cost‐efficient systems; CW radar; digital beamforming; FM radar; FMCW multiple‐input multiple‐output radar; FMCW radar system; frequency 2.4 GHz; frequency modulation; IAA beamforming; iterative adaptive algorithm; iterative methods; low‐frequency clock; MIMO radar; radar signal processing; radar simulator; remote RX site; remote TX site; Research Article; synchronisation; transmit site; trigger distribution system; iterative methods; radar simulator; FMCW radar system; CW radar; trigger distribution system; low-frequency clock; FMCW multiple-input multiple-output radar; FM radar; cost-efficient systems; synchronisation; radar signal processing; collocated antennas; digital beamforming; frequency 2.4 GHz; MIMO radar; remote TX site; IAA beamforming; remote RX site; bandwidth 100 MHz; continuous wave multiple-input multiple-output radar system; frequency modulation; iterative adaptive algorithm; array signal processing; transmit site
• ISSN: 1751-8784; 1751-8792; 1751-8792
• DOI: 10.1049/iet-rsn.2018.5112

This work presents the design of a frequency modulated continuous wave (FMCW) multiple-input multiple-output radar system with collocated antennas. A key part of this article is the modification and application of the iterative adaptive algorithm (IAA) for digital beamforming to an FMCW radar system. The implemented system operates in the 2.4 GHz Industry, Scientific and Medical band with 100 MHz of bandwidth and consists of a transmit (TX) site with four antennas and a receive (RX) site with four antennas. The angular resolution is greatly improved from 15° with the common delay-and-sum beamforming to only 5° with IAA beamforming, which was verified by the results from a radar simulator and by a field test with the implemented hardware. The challenge of synchronisation and maintaining phase coherence in systems with remote TX and RX sites is also addressed by proposing a low-frequency clock and trigger distribution system. This approach allows for cost-efficient systems which can be distributed over longer distances.