We have developed a 3-D high-resolution radar at 300 GHz with a cell resolution of 1 1.6 1.6 cm at a standoff distance of 8 m for security applications. The selection of an operating frequency of 300 GHz, a bandwidth of 27 GHz, and a field of view of 50 90 cm improves the through-clothes imaging of person-borne concealed objects. The radar's antenna design allows single-pixel imaging at a frame rate of two frames per second. A reduction in cost and power consumption and improvements in image quality are additional requirements taken into account in the design of this radar system.Index Terms-Continuous-wave linear-frequency modulation (CW-LFM), field of view (FoV), imaging radar, millimeter wave.

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We propose a framework for the systematic analysis of mobile phone data to identify relevant mobility profiles in a population. The proposed framework allows finding distinct human mobility profiles based on the digital trace of mobile phone users characterized by a Matrix of Individual Trajectories (IT-Matrix). This matrix gathers a consistent and regularized description of individual trajectories that enables multi-scale representations along time and space, which can be used to extract aggregated indicators such as a dynamic multi-scale population count. Unsupervised clustering of individual trajectories generates mobility profiles (clusters of similar individual trajectories) which characterize relevant group behaviors preserving optimal aggregation levels for detailed and privacy-secured mobility characterization. The application of the proposed framework is illustrated by analyzing fully anonymized data on human mobility from mobile phones in Senegal at the arrondissement level over a calendar year. The analysis of monthly mobility patterns at the livelihood zone resolution resulted in the discovery and characterization of seasonal mobility profiles related with economic activities, agricultural calendars and rainfalls. The use of these mobility profiles could support the timely identification of mobility changes in vulnerable populations in response to external shocks (such as natural disasters, civil conflicts or sudden increases of food prices) to monitor food security.

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