Amplitude modulation of multiple carriers provides a pulse width modulated train resulting in a novel and effective communication mechanism to overcome difficulties in certain RF applications, particularly in the area of Radio Frequency Identification (RFID). A novel conceptual pulse is formed and developed using a set of RF frequencies, such as ultra wideband frequencies, amplitude modulated to form a pulse width modulated binary coded signal. The concept is to wirelessly convey information only to a receiver at a specified distance or range. The RF energy may continue on in space, but receivers of the same design would only receive information from a transmitter if the receivers are located at a specified distance. Equivalent receivers at all other distances would see noise.