An exemplary method includes: receiving at each of at least three antenna elements of a positioning device a wireless signal having modulated thereon an identifier relating to a transmitting device; obtaining complex signal parameters of a signal received at each of the at least three antenna elements; determining a measure of a strength of the received wireless signal; comparing the measure to a threshold associated with the identifier; if the measure exceeds the threshold, processing the complex signal parameters to determine a bearing of the transmitting device from the positioning device; and if the measure does not exceed the threshold, discarding the complex signal parameters without processing them to determine a bearing. An exemplary apparatus and computer readable medium configured to perform the method are also disclosed.