A wireless microphone works by using a wireless transmitter, which is incorporated into the microphone or attached to a body pack transmitter. The battery-operated wireless transmitter includes an antenna for broadcasting sounds. Another essential device that makes a wireless microphone work is a wireless receiver, which is adjusted to the transmitter's electromagnetic wavelength, typically Very High Frequency or Ultra High Frequency. The receiver connects to a closed system headset or other output device.

A handheld wireless microphone requires a person to hold the microphone, and it produces varying volume levels depending on the distance from the sound source. Some handheld wireless microphones come with built-in transmitters and operate up to 300 feet.

In comparison, hands-free wireless microphones, such as lapel, collar and headband microphones, can be used with more flexibility. These microphones are suitable for individuals who want to use their hands while speaking. For example, people who use projectors, computers or other multimedia equipment while speaking during presentations benefit from using hands-free wireless microphones.

The type of antenna in a receiver and the signal wavelength are important factors affecting the quality of transmission. Very High Frequency radio signals are generally less expensive, as they require only a single antenna instead of diversity antennae. Ultra High Frequency radio signals provide better transmission quality, allow simultaneous operation of systems and work well with diversity receivers.