What is the term for waves of frequency that are transmitted above MUF that will pass through the ionosphere?

The term for waves of frequency that are transmitted above the Maximum Usable Frequency (MUF) which can pass through the ionosphere is known as space waves. Space waves are not refracted back to Earth by the ionosphere, which means they propagate directly into space. This characteristic allows them to travel over long distances without being affected by the ionospheric conditions that typically influence lower frequency waves.

In contrast, waves below the MUF are refracted by the ionosphere, allowing for different propagation modes such as ground waves and sky waves. Ground waves travel along the surface of the Earth, while sky waves are reflected back to Earth by the ionosphere. Absorption waves, while they do exist, are not specifically defined in the context of frequencies above MUF. Understanding these distinctions helps in grasping the behavior of different wave types in radio propagation.