A power combiner is a device enabling the power from several inputs to be combined into a single output.
The generation of high power is necessary in certain applications, for example in radar systems in order to emit a high power signal or communication systems in order to deliver a high power signal to a communication channel.
As the level of power output of a single power amplifier is often insufficient, a power combiner is necessary to add or combine power outputs from several power amplifiers.
Thus, power combiners are often used with a set of power amplifiers, each power amplifier amplifying an input signal and supplying an output signal. The power combiner combines the power of the output signals from the power amplifiers and generates a total output power.
Numerous architectures for power combiners exist. A spatial power combiner is one type of power combiner constituted by a cavity supplied by signals coming respectively from a set of input transmission lines. The power coming from each line is combined and collected into a central output transmission line.
In the current spatial power combiners, the inputs of the power combiner are not isolated from each other. Thus, as each input of the combiner influences the other inputs, a failure at one input or at components linked to that input is able to be propagated to the other inputs.
Furthermore, a fault of a single power amplifier may lead to a large degradation in the performance of the power combiner, which may lead to a fault in the operation of the device in which the power combiner is used.