High-resolution 160 GHz imaging MIMO radar using MMICs with on-chip frequency synthesizers

Abstract

A high-resolution frequency modulated continuous wave imaging radar for short-range applications is presented. A range resolution of about 1cm is achieved with a bandwidth of up to 16GHz around 160GHz. In order to overcome losses and large tolerances on a printed circuit board (PCB), 8 coherently coupled monolithic microwave integrated circuits (MMIC) are used, each with one transmit and receive antenna on-chip and each representing a single channel radar system. The signals on the PCB are below 12GHz, which facilitates fabrication and enables a design with low-cost substrates. The MMIC comprises a phase noise optimized architecture with a fully integrated on-chip frequency synthesizer. Due to partly uncorrelated phase noise between the frequency synthesizer components, the noise level is increased in bistatic radar measurements between two different MMICs, which is explained by a thorough phase noise analysis. Time-division multiplexing is used to realize a multiple-input multiple-output system with a virtual array of 64 elements and an angular resolution better than 1.5° for the designed array. The positioning tolerances of the MMICs are included into the design resulting in a robust array design. The high-resolution radar performance is proven by imaging radar measurements of two exemplary scenarios.