RF Exposure calculator
This page of converters and calculators section covers RF Exposure calculator. Specific Absorption Rate and incident power density calculations can be done by RF exposure calculator. SAR (Specific Absorption Rate) is used as unit of measure to determine RF exposure limit. It has unit of W/Kg , rate of energy absorption for unit mass of substance.
RF exposure calculator example:
Electric field(rms)= 5, conductivity= 1,
mass density = 1.3E03 (1.3 x 103)
RF Exposure limit or SAR = 0.0192 W/kg, Power density = 0.066
Conductivities of scalp, CSF, skull and brain are specified as 0.3300, 1.0000, 0.0042 and 0.3300 S/m commonly.
RF exposure calculator equation
Electromagnetic radiation exposure above certain limit can cause harmful effects to human being.
This RF exposures can cause health risks in the form of health deficiency, brain deseases and cancers of
various forms.
RF exposures are of two types viz. ionising and nonionising. ICNIRP have come up with RF exposure limits for general public and
occupational applications.
For the assessment of the RF exposure level, it is required to measure following:
• Electric field intensity
• Magnetic field intensity (H)
• Specific absorption rate (SAR)
The selection of measurement depends on the location of the observer (i.e. near field or far field region)
and field impedance.
Following equation or formula is used for RF exposure limit calculation.
Hence this RF exposure calculator is very useful for various reasons.
Calculating E from Transmitter power and Gain to be used in RF exposure calculator
Sometimes it is required to calculate electric field(E)
to be used in the above RF exposure calculator for SAR calculation.
Following calculator calculates Electric Field(E) in V/m
from transmitter power(Pt) and antenna gain(Gt) at a distance r from the antenna position.
E = ( (30*Pt*Gt)0.5 / r ) V/m
EXAMPLE:
INPUTS: Antenna power = 23dBm, Antenna Gain = 12 dBi, Distance = 800 meters
OUTPUT: RMS electric field =0.012 V/m
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