Roberto Quaglia (Senior Lecturer) Cardiff University presenting at Interlligent UK's 2024 RF & Microwave Design Seminar.
The Doherty Power Amplifier is the workhorse of mobile base-station transmitters. In conjunction with powerful digital linearizers, it provides efficient operation when amplifying the demanding OFDM signals required in modern mobile systems, allowing for more sustainable operational costs of the mobile infrastructure.
However, its application to the mm- and cm-wave is not straightforward, and it has been limited so far. This presentation tries to understand why this has (not) happened, simplifying the picture and deriving the key limiting factors. In doing so, it will also identify some possible routes to make the Doherty a viable solution for higher-frequency transmitters. The presentation discusses some practical examples of experiments on Doherty Power Amplifiers from 7 GHz up to 30 GHz.