What is an L-network composed of?

An L-network is a type of circuit used in radio frequency applications primarily for impedance matching. It typically consists of an inductor and a capacitor arranged in a specific configuration. The combination of these two reactive components allows the L-network to transform impedances, making it highly effective in connecting different parts of an RF system or ensuring maximum power transfer.

The inductor and capacitor in the L-network work together to create various combinations of voltage and current phase shifts, helping to achieve the desired impedance. This is crucial in applications where matching the load to the source impedance is necessary for optimal performance.

In contrast, the combinations of other components, such as a resistor alone or with capacitors, do not form an L-network. Additionally, two capacitors would not constitute an impedance-transforming network, as capacitors cannot provide the necessary phase shifts required for this function in the same way that a combination of an inductor and a capacitor can. Therefore, the correct answer indicates the fundamental components that define an L-network in RF design.