Radio frequency, or RF, is a carrier, or alternating current with or without a signal, at a frequency that can radiate, or propagate, if not shielded. Such frequencies account for the following parts of the electromagnetic spectrum:
- VLF: 3-30 kHz
- LF: 30-300 kHz
- MF: 300-3000 kHz
- HF: 3-30 MHz
- VHF: 30-300 MHz
- UHF: 300-3000 MHz
- SHF: 3-30 GHz
- EHF: 30-300 GHz
Analog signals that are not RF include IF (intermediate frequency) and AF (audio frequency, 20-20000 Hz).