A method is disclosed. In various examples, the method may include receiving an instruction for generating a ranging signal, and transmitting the ranging signal at least partially responsive to the instruction. In various examples the ranging signal may be transmitted via a terrestrial transmitter for transmitting radio waves having encoded messaging information and timing information for one or more of positioning, navigation and timing. In various examples, the ranging signal may exhibit a first ranging pulse and a second ranging pulse of a pulse group and an encoded transmitter identifier, the transmitter identifier encoded by modulating an inter-pulse interval defined between a start of the first ranging pulse and a start of the second ranging pulse.