Systems and methods associate operators with machinery, such as materials-handling vehicles. Embodiments of the disclosed system comprise a first communication module configured to determine a distance between a frame of reference associated with a vehicle and respective portable devices and first logic configured to designate a first portable device as an operator device based, at least in part, on a first distance determined by the communication module. The first logic may be further configured to exclude the first portable device from a pedestrian detection function in response to classifying the first portable device as an operator device.