What is the primary function of a rotary joint in a waveguide system?

In a waveguide system, a rotary joint is primarily used to connect a stationary waveguide to a rotating component, such as an antenna array. This connection allows electromagnetic waves to pass through while accommodating the rotational movement of the antenna without causing any interruptions or losses in signal. The design of a rotary joint ensures that the integrity of the waveguide system is maintained, facilitating effective energy transfer despite physical motion.

The other options, while related to waveguide functionality, do not accurately describe the role of a rotary joint. For instance, coupling waveguides at right angles or acting as a switch involves different configurations and components designed specifically for those purposes. Similarly, maintaining pressurization could pertain to certain types of waveguide systems but does not directly reference the function of a rotary joint. Therefore, the clear purpose of connecting a stationary waveguide to rotating equipment is what makes the correct answer definitive.