Electromagnetic radiation consists of various types of waves characterized by their frequency and wavelength. The different types of electromagnetic radiation, in increasing order of frequency and energy, include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.
The primary distinction between these types lies in their frequencies and wavelengths, which determine their behavior and applications. Radio waves have the lowest frequencies and longest wavelengths, while gamma rays have the highest frequencies and shortest wavelengths. As you move from radio waves to higher frequencies, the wavelength decreases, and the energy of the radiation increases.
Now, regarding your question, if a signal generator produces a signal with a higher frequency than radio waves, it would indeed be generating microwaves. Microwaves have frequencies ranging from about 300 MHz (megahertz) to 300 GHz (gigahertz), which fall between radio waves and infrared radiation in the electromagnetic spectrum. Microwaves are commonly used for communication, cooking, and other applications due to their ability to penetrate materials and their interaction with water molecules.
It's worth noting that the division between different types of electromagnetic radiation is somewhat arbitrary and often defined based on practical considerations rather than strict boundaries. There is some overlap in the frequency ranges between adjacent types, and the categorization is based on the typical applications and behaviors associated with each range.