Embodiments of the present disclosure describe systems, methods, and apparatuses for reviving a wireless power receiver client over-the-air. More specifically, dual-mode active/passive wireless power receiver clients are described that can passively harvest RF energy in order to obtain enough energy to rejoin a wireless power network where the client can actively harvest RF energy (the client receives directed or isolated wireless power from a wireless power transmission system). For example, a wireless power receiver client can harvest RF energy while idle or off, e.g., when no beacon or other communications are being sent or received, or, in some instances, asynchronously in order to compliment and/or protect one or more elements of the system such as, for example a radio transceiver.