Frequency scaling of power reclamation networks in outphasing PA architectures

Outphasing power amplifiers (PAs) with power reclamation networks are an attractive solution for maintaining a constant PA load during outphasing while minimizing energy lost. Power reclamation networks have only been demonstrated at frequencies below 2 GHz. In this work, we examine power reclamation networks for outphasing PA topologies and investigate how their efficiency scales with frequency. Our results show that at mm-wave frequencies, power reclamation network efficiency is dominated by the current in the resonant portion of the rectifier and that this loss can increase disproportionately with frequency, thus placing a key limitation on the efficiency of power reclamation networks at mm-wave frequencies.