Device, systems, and/or techniques for using sub-channel signaling information between an access point and a first station are disclosed. In one aspect, a method performed by a station (STA) includes: receiving, from a neighboring STA in an overlapping basic service set (OBSS), a physical (PHY) layer preamble that includes a signal field indicating a plurality of sub-bands and associated power thresholds for Uplink Orthogonal Frequency-Divisional Multiple Access (UL OFDMA) transmission, that are available for OBSS spatial reuse (SR) by the STA; and sending, to an AP with which the STA is associated, an UL OFDMA transmission using a sub-band of the plurality of sub-bands and an associated power threshold indicated in the signal field. Additional embodiments are disclosed.