RF Exposure

FCC ID: EMOIBTW281

RF Exposure Info

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FCCID_4326646

$FCC ID : EMOIBTW281 RF EXPOSURE EVALUATION According to FCC 1.1310: The criteria listed in the following table shall be used to evaluate the environment impact of human exposure to radio frequency(RF) Radiation as specified in §1.1307(b) Limits for Maximum Permissible Exposure (MPE) Frequency Electric Field Magnetic Field Power Average Time 2 Range(MHz) Strength(V/m) Strength(A/m) Density(mW/cm ) (A) Limits for Occupational/Control Exposures 300-1500 -- -- F/300 6 1500-100000 -- -- 5 6 (B) Limits for General Population/Uncontrol Exposures 300-1500 -- -- F/1500 6 1500-100000 -- -- 1 30 11.1 Friis transmission formula: Pd= (Pout*G)\ (4*pi*R2) Where Pd= Power density in mW/cm2 Pout=output power to antenna in mW G= Numeric gain of the antenna relative to isotropic antenna Pi=3.1416 R= distance between observation point and center of the radiator in 20cm Pd the limit of MPE, 1mW/cm2. If we know the maximum gain of the nd total power input to the antenna, through the calculation, we will know the distance where the MPE limit is reached. 11.2 Measurement Result conducted Max Channel conducted Antenna Evaluation Power density power tune-up Freq. modulation power Tune-up power (dBm) Gain result Limits (dBm) power (MHz) (mW) Numeric (mW/cm2 ) (mW/cm2 ) (dBm) BT: 2402 GFSK 1.46 1.640 1.6dBm to 3.6dBm 3.6 0.87 0.00040 1 2441 GFSK 1.59 2.021 1.6dBm to 3.6dBm 3.6 0.87 0.00040 1 2480 GFSK 2.24 3.500 1.6dBm to 3.6dBm 3.6 0.87 0.00040 1 2402 π/4 -DQPSK 2.78 4.437 4.4dBm to 6.4dBm 6.4 0.87 0.00076 1 2441 π/4-DQPSK 3.00 4.773 4.4dBm to 6.4dBm 6.4 0.87 0.00076 1 2480 π/4-DQPSK 4.13 6.162 4.4dBm to 6.4dBm 6.4 0.87 0.00076 1 2402 8DPSK 2.92 4.659 4.5dBm to 6.5dBm 6.5 0.87 0.00077 1 2441 8DPSK 3.17 5.017 4.5dBm to 6.5dBm 6.5 0.87 0.00077 1 2480 8DPSK 4.13 6.163 4.5dBm to 6.5dBm 6.5 0.87 0.00077 1$

BLE:
conducted Max
Channel conducted Antenna Evaluation Power density
power tune-up
Freq. modulation power Tune-up power (dBm) Gain result Limits
(dBm) power
(MHz) (mW) Numeric (mW/cm2 ) (mW/cm2 )
(dBm)
BLE:
2402 GFSK 2.16 3.338 1.4dBm to 3.4dBm 3.4 0.87 0.00038 1
2440 GFSK 1.57 1.958 1.4dBm to 3.4dBm 3.4 0.87 0.00038 1
2480 GFSK 1.39 1.423 1.4dBm to 3.4dBm 3.4 0.87 0.00038 1

RF EXPOSURE (BT+BLE) = 0.00077+0.00038=0.00115 mW/cm2 <1 mW/cm2

Note: Antenna gain: -0.61 dBi

Document Created: 2019-06-17 17:43:25
Document Modified: 2019-06-17 17:43:25