Systems and techniques relating to wireless networking, and target wake time (TWT) scheduling for transmissions employing an Orthogonal Frequency-Division Multiple Access (OFDMA) digital modulation channelization include: receiving a frame at a wireless device, wherein a format of the frame comprises (i) a field indicating a target wake time, (ii) a first subfield having a first value that indicates a digital modulation channelization scheme, and (iii) a second subfield having a second value that indicates a transmission direction; and powering on the wireless device at the target wake time indicated by the field in the frame, wherein the powering on the wireless device enables the wireless device to transmit additional frames via a wireless channel based on (i) the first value set in the first subfield of the frame and (ii) the second value set in the second subfield of the frame.