I want to explain briefly the EMR that comes from Telecommunication towers
They are plane traveling waves at approximate frequency range of 800 MHz to 2400 MHz. The power output is in order of few watts. In principle, they are not much different that any other radio wave, such as broadcast TV, AM or FM radio, etc. Major differences between these is frequency, directionality, power level, etc.
There are several frequency bands, just google 'cellular frequencies' Cell towers have directional antennas that broadcast with a beam power pattern that is controlled so that the EM energy in concentrated in a horizontal pattern to maximize the signal to users. The antenna are also sectorized so that space division multiple access (SDMA) is acheived. The cell tower transmitter have just a few watts but the high gain antennas can raise the effective radiated power (ERP) to 10-20 watts. The cell tower coverage area in controlled by the power level, the antenna gain, and the sectorization of the antenna for SDMA. For example, in cities, the coverage area is made small to avoid interference to nearby cell towers. In rural areas, the tower uses higher RF power levels. Along rural interstates, the towers use antenna the maximize the ERP in both directions along the interstate. Good luck
Plane travelling waves. Usually every base station antenna provides three sectored beams. The maximum allowable field intensity varies from country to country and depends on the standard followed by a particular country. Till 2012, India followed ICNIRP regulations but then in the public zone, the maximum field strength has been reduced by a factor of 10. However, in occupational zone near the antenna, no modification to ICNIRP standard has been done.
Dear Bhaskar Gupta ,
Do you know why India has reduced maximum field strength by a factor of 10.
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