a computer implemented method , program and system utilizing a number of field - deployed sensors to accurately detect and classify objects / events of interest within a sensor field including the detection / classification of human beings travelling on - foot or with vehicles and their direction of travel . in particular , the method , computer program and system are operable to determine whether a detected target is an animal , human or vehicle via analysis of received acoustic and sensor data . the analyses performed include comparison / correlation of the sensor data to known seismic cyclostationary signatures , acoustic and seismic characteristics of human footsteps and travel tendencies , and acoustic and seismic characteristics of non - human footsteps and travel tendencies .