The modular microwave ablation system of the present disclosure includes a microwave instrument, a microwave generator, and one or more auxiliary modules that include circuitry for performing functions related to the operation of the microwave generator. The one or more auxiliary modules are removably connected to the microwave generator. The microwave generator includes a microwave signal generator that generates a microwave signal； a microwave generator controller in communication with the microwave signal generator； one or more terminals that connect to the one or more auxiliary modules, respectively； and a power supply and/or a power distribution module coupled to the microwave signal generator, the microwave generator controller, and the one or more terminals. The one or more terminals provide (1) power from the power supply and/or power distribution module to the one or more respective auxiliary modules and (2) communication signals to and from the one or more respective auxiliary modules.
