Methods, systems and apparatuses for dynamic spectrum access by both primary users (PUs) and secondary users (SUs) are disclosed. In one embodiment, a method for communicating over a channel may include obtaining, at a secondary transmitter, first and second signals intended for a primary receiver and secondary receivers, respectively; generating, at the secondary transmitter, an assist signal based, at least in part, on the obtained first signal; generating, at the secondary transmitter, a data signal based, at least in part, on the obtained second signal; determining, at the secondary transmitter, a power split ratio between the data signal and the assist signal based, at least in part, on any of a power and a signal-to-noise ratio of the first signal; and generating, at the secondary transmitter, a third signal comprising (i) the data signal and (ii) the assist signal in accordance with power split ratio.