The electromagnetic spectrum has a range of magnetic signals that encompass all frequencies in electrical and electronic systems. the frequencies include
- Extremely low frequency (E.L.F) @ 3-30Hz – this include alternating current power line frequencies, submarine communication and all frequencies under human audio range.
- Super low frequency (S.L.F) @ 30-300Hz – this is used for communication to and with submarines.
- Utra low frequency (U.L.F) @ 300-300 Hz – this frequency is used for communication with submarine and enclosed mine areas.
- Very low frequency (V.L.F) @ 3-30 KHz- this is used for heart rate monitors that are wireless, military sound equipment, clock time signals
- Low frequency (L.F) @ 30-300 KHz – used for long wave broadcasting, Radio frequency identification i.e R.F.I.D, aeronautical & marine navigation.
- Medium frequency (M.F) @ 300-3000 KHz – used for Amplitude Modulation i.e A.M broadcasting i.e medium wave frequencies.
- High frequency (H.F) @ 3-30MHz used in short wave frequencies.
- Very high frequency (V.H.F) @ 30-300 MHz – used for Frequency modulation F.M broadcasts, Television broadcasts.
- Ultra high frequency (U.H.F) @ 300-3000MHz – used for television broadcasts, microwave, mobile phone, satellite communication, radar.
- Super high Frequency (S.H.F) @ 3-30 GHz – used in radio calls, wireless local area network L.A.N, satellite communication.
- Extremely high frequency (E.H.F) @ 30-300 GHz – used in satellite communication, telephony, computer data communication.
- Tremendously high frequency (T.H.F) @ 300-3000 GHz – used in amateur radio, computer communications & remote sensors.
- Infrared – used in remote control of T.V receivers.
- Voice Frequency – it is the normal frequency range of human speech.
- visible spectrum – This is where light is used for communication, light waves are modulated and transmitted through medium.
All this frequencies form the electromagnetic spectrum and they are closely guarded from interference by the communications authority of individual countries or globally to avoid noise, people hacking into other peoples frequency, malice or interference of other peoples frequency. it may also protect organizations, police, civil aviation or military to guarding their secrets from other people i.e by having their own frequencies for easier communication