Electrosurgical generator for delivering microwave energy at multiple frequencies

Abstract

The invention relates to an electrosurgical system for delivering electromagnetic energy at a plurality of frequencies to cause different effects on biological tissue at a treatment site, and in particular to an electrosurgical generator. The electrosurgical generator comprises an electromagnetic signal supply unit for generating microwave energy to be conveyed on each of a plurality of microwave channels, wherein each of the plurality of microwave channels is arranged to convey microwave energy at a different frequency; an output port configured to be connectable to a probe for delivering microwave energy from the plurality of microwave channels; and a signal combiner configured to connect the plurality of microwave channels to the output port, wherein the signal combiner comprises a band stop filter module disposed at a distal end of each of the plurality of microwave channels, wherein the band stop filter module for each microwave channel is configured to block microwave energy at the frequency conveyed on the other microwave channels; and a common signal pathway extending between the output port and a junction at which the plurality of microwave channels are connected.