This disclosure provides methods, devices and systems for increasing the transmit power of wireless communication devices operating on power spectral density (PSD)-limited wireless channels. Some implementations more specifically relate to tone mapping techniques and packet designs that support duplicate (or “DUP mode”) transmissions to multiple users. In some implementations, an access point (AP) may transmit a PPDU that includes first user data and second user data, where at least the first user data is transmitted in a DUP mode. As such, the first user data may be mapped to a number (N) of tones spanning a first RU in accordance with a dual carrier modulation (DCM) scheme, and a duplicate copy of the first user data may be mapped to N tones spanning a second RU in accordance with the DCM scheme. In some implementations, the second user data also may be transmitted in a DUP mode.