In a two-way ranging scheme where a first apparatus (e.g., device) determines a distance to a second apparatus (e.g., device), specified packets are sent between these apparatuses at specified times to facilitate the determination of the distance. In some aspects, these packets may be defined and/or sent in a manner that enables the apparatuses to detect a leading edge of a received packet with a high degree of accuracy. For example, an apparatus may transmit a packet a defined period of time after transmitting or receiving another packet. In addition, a packet may comprise a defined symbol sequence that is used by an apparatus that receives the packet to identify a leading edge of the packet.