Understanding Electromagnetic Spectrum and Their Uses

Radio frequency (RF) includes any of the electromagnetic wave frequencies from around 3 kHz to 300 GHz, which include frequenciesused for communications or radar signals. Extremely to very low frequency (to 20KHz) are generally sound based and can be heard by most humans.


These are the radio spectrums after which are the light spectrum and then the radiation spectrum which includes x-rays, gamma-rays and cosmic rays.

The Radio Spectrum

Sound (audible) is in the VLF range of upto 10/20KHz KHz (Kilohertz) while ultra-sonics range from 10 KHz to 1 MHz (Megahertz). Radio broadcasts are either AM (LF to MF) or FM (HF to VHF). Microwaves are in the VHF to EHF range and may extend further as the understanding and measurement becomes more advanced.

Frequency spectrum is licensed by the respective Governments in the interests of security and delivers a level playing field for telecom enterprises. In between FM broadcast and UWB lie the ISM bands. The lower range of ISM bands belong to the 315 – 915 MHz while at present ISM bands are also allowed in the 2.4 GHz range. ISM pertains to Industrial, Scientific and Medical uses which include Space, defence, electronic disruption, radar and navigation systems.

Raditek is a leading manufacturer of amplifiers in ISM band and their products are increasingly used in medical laboratories, EMC (Electromagnetic compatibility) and plasma physics.