RF combiners and splitters are used in a variety of RF applications and allow RF power to either be split or combined in a scenario where characteristic impedance is maintained.
Essentially, RF power combiners and splitters are the same things, as the same circuits are able to be used to split and combine RF power. The only key difference between the two is that RF power is implemented at one port and extracted from the other with an RF splitter, while power is implemented in the opposite direction for an RF combiner.
There are many different types of resistive splitters and dividers which can be used for an RF division or split in any ratio by selecting the right resistor and configuration values. They can also provide an accurate impedance match over various bands of frequencies, as long as the right sort of resistor and construction methods is utilized.
Many different configurations are able to be used for resistive power splitters and RF resistive power dividers.
Categories of RF Splitters
There are basically two different types of RF splitters:
▪ Resistive power splitters – These power splitters and combiners make use of resistors, and although they can uphold the characteristic impedance of a system, using resistors allows loss above the minimum caused by splitting action.
▪ Hybrid power splitters – These use transformers and introduce low levels of loss. Even though there is some physical loss within the transformer, the most significant loss is that which comes from the splitting process, considering the fact that various outputs share the same signal.
Pros and Cons of Resistive Splitters and Combiners
There are a few advantages and disadvantages of resistive splitters and combiners which should be considered before deciding which type of splitter or combiner to use.
Pros
They’re simple – Resistive splitters or combiners are rather simple in nature, as they consist of only resistors. They are able to be made very easily in a circuit that requires very little preparation and design.
They’re affordable: Since they are only made from resistors, the expense of a resistive combiner or splitter is minimal.
They offer a wide frequency range: As long as suitable resistors and construction tactics are employed, the frequency response of resistive splitters and combiners can extend over a broad frequency range.
Cons
Loss – Power is often lost above the reduction in power level when using resistors, which is caused by the division of the power between many outputs in a splitter.
With this information in mind, you should be able to make a more sound decision about which RF splitter or combiner to use.
