This paper presents a signal processing method to detect human cough signals with a millimeter-wave frequency-modulated continuous-wave (FMCW) radar. Tiny vibrations induced by coughing can be extracted by using the phase demodulation technique of the FMCW radar. A body motion artifact cancellation (BMAC) technique is exploited to suppress motion artifacts, which can easily overwhelm and distort the small vibrations. This allows measuring the vibration frequency of the cough signal even when large-scale body motions are spontaneously involved. Numerical simulations are conducted to evaluate detection probability and accuracy of the cough signal with the proposed method, including the analysis for effects of FMCW chirp nonlinearity. The proposed techniques are also verified through experiments with a 60-GHz FMCW radar.

Radar sensors are emerging as solutions for perceiving surroundings and estimating ego-motion in extreme weather conditions. Unfortunately, radar measurements are noisy and suffer from mutual interference, which degrades the performance of feature extraction and matching, triggering imprecise matching pairs, which are referred to as outliers. To tackle the effect of outliers on radar odometry,$a$novel outlier-robust method called ORORA is proposed, which is an abbreviation of Outlier-RObust RAdar odometry. To this end, a novel decoupling-based method is proposed, which consists of graduated non-convexity (GNC)-based rotation estimation and anisotropic component-wise translation estimation (A-COTE). Furthermore, our method leverages the anisotropic characteristics of radar measurements, each of whose uncertainty along the azimuthal direction is somewhat larger than that along the radial direction. As verified in the public dataset, it was demonstrated that our proposed method yields robust ego-motion estimation performance compared with other state-of-the-art methods. Our code is available at https://github.com/url-kaist/outlier-robust-radar-odometry.

This paper presents a direct-conversion transceiver technology for full digital DS-UWB applications. It is implemented in 0.18 []m CMOS technology and total current consumption is 143 mA including PLL, VCO. The full chip size is 9 mm2, packaged in MLF 64 pin.