Confidential – Version 1.0
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Copyright © 2018 ABonAir Ltd.
< 1 cm and Far Filed is > 1cm. (RFar
Field = 6/2*3.14=0.95cm)
At 6Ghz frequency the Wavelength is 50 mm. The Antenna
Radiation element
size is 20mm, hence shorter then the wavelength, hence Near
filed is < 0.8 cm and Far Filed is > 0.8 cm. (RFar Field =
5/2*3.14=0.8cm)
Exposure levels are based on the exposure limits for the general
public given by the ICNIRP guidelines [B.6.1]. In our case,
Localized SAR 2W/kg for head and trunk over 10 gram tissue.
Based on a study of dipole antennas of different lengths and at
different distances, a simple equation was developed for
predicting higher values of the low-power exclusio
n levels (Pmax′
):
Pmax '= exp[As+Bs2 +Cln(BW)+D] (Eq. E.1)
where s represents the nearest separation distance between the
wireless device and the user’s body, BW is the free-space
antenna bandwidth, and A, B, C and D are third-order polynomials
of frequency. The bandwidth defined as the ratio between the
stored and the radiated energies of the antenna. In the equation
(E.1), s is expressed in mm and BW is expressed in percent. The
frequency dependent parameters A, B, C and D can be found
from the following equations, where f is the frequency in GHz. For
compliance with the SAR limit of SARmax = 2 W/kg averaged
over m =10 g in ICNIRP Guidelines [1] and IEEE Std C95.1-2005
[4], use Equations (E.2) to (E.5)
in Equation (E
.1):
A= (− 0,4588 f 3 +4,407 f 2 − 6,112 f +2,497)/ 100
(Eq. E 6)
