A
sensing system (11) includes a first
radar sensing
assembly (10; 3104, 3106; 4100, 4200) and an analysis
system (18). The first
radar sensing
assembly (10; 3104, 3106; 4100, 4200) measures plural distances (12; 22, 30; 42, 50, 60, 70, 80; 4102, 4202) to a first target location (16) at different times using
radar. The analysis
system (18) receives the plural distances (12; 22, 30; 42, 50, 60, 70, 80; 4102, 4202) from the first radar sensing
assembly (10; 3104, 3106; 4100, 4200) and quantifies movements of a target object (14) at the first target location (16) at the different times by calculating differences in the plural distances (10; 3104, 3106; 4100, 4200) measured by the first radar sensing assembly (10; 3104, 3106; 4100, 4200). The analysis
system (18) generates one or more first quantified
activity level values indicative of the movements of the target object (14) at the first target location (16) using the differences in the plural distances (12; 22, 30; 42, 50, 60, 70, 80; 4102, 4202) that are calculated.