Last advances in freehand sensing for mmWave imaging

This contribution presents the last developments of freehand systems for electromagnetic sensing, focusing on millimeter-wave (mmWave) freehand imaging systems. In particular, the impact of positioning errors in the quality of the obtained electromagnetic images is discussed, emphasizing the importance of using tracking systems that can be embedded in the freehand device. In addition, several challenges faced by freehand systems to achieve a higher scanning speed and a reduced computational burden towards fully autonomous portable systems are summarized.