MPE Calculation

FCC ID: P5IC1K01

RF Exposure Info

Download: PDF
FCCID_1081506

FCC-ID P5IC1K01 IC-ID (Industry Canada) 1478A-C1K01 PREDICTION OF MPE AT A GIVEN DISTANCE Calculations can be made to predict RF field strength and power density levels around typical RF sources using the general equations (3) and (4) on page 19 of the following FCC document: “OET Bulletin 65, Edition 97-01 - Evaluating Compliance with FCC Guidelines for Human Exposure to Radio frequency Electromagnetic Fields”. These equations are generally accurate in the far field of an antenna but will over predict power density in the near field, where they could be used for making a “worst case” prediction. S = PG/4πR2 (3) Where S = power density (in appropriate units, e.g. mW/cm2) P = power input to the antenna (in appropriate units e.g. mW) G = power gain of the antenna in the direction of interest relative to the isotropic radiator R = distance to the center of radiation of the antenna (appropriate units e.g. cm) or, S = EIRP/4πR2 (4) Where EIRP = Equivalent Isotropically radiated power General Limits: §1.1307 Cellular Radiotelephone Service (subpart H of part 22) Non-building-mounted antennas: height above ground level to lowest point of antenna < 10 m and total power of all channels > 1000 W ERP (1640 W EIRP) §1.1307 Personal Communications Services (part 24) Broadband PCS (subpart E): non-building-mounted antennas: height above ground level to lowest point of antenna < 10 m and total power of all channels > 2000 W ERP (3280 W EIRP) §1.1310 LIMITS FOR MAXIMUM PERMISSIBLE EXPOSURE (MPE) (B) Limits for General Population/Uncontrolled Exposure 300–1500 MHz: f/1500 mW/cm² 1500–100,000 MHz: 1.0 mW/cm² §2.1091 No routine evaluation required when the device …operate at frequencies of 1.5 GHz or below and their effective radiated power (ERP) is 1.5 watts or more, or if they operate at frequencies above 1.5 GHz and their ERP is 3 watts or more.

FCC-ID P5IC1K01 IC-ID (Industry Canada) 1478A-C1K01 §24.232 (a) Base stations are limited to 1640 watts peak equivalent isotropically radiated power (e.i.r.p.) with an antenna height up to 300 meters HAAT. b) Mobile/portable stations are limited to 2 watts e.i.r.p. peak power, … §22.913 (a) Maximum ERP. The effective radiated power (ERP) of base transmitters and cellular repeaters must not exceed 500 Watts. The ERP of mobile transmitters and auxiliary test transmitters must not exceed 7 Watts. The table below is excerpted from Table 1B of 47 CFR 1.1310 titled “Limits for Maximum Permissible Exposure (MPE), Limits for General Population/Uncontrolled Exposure” 2 Frequency Range (MHz) Power Density (mW/cm ) 300 -1500 f/1500 1500 - 100000 1.0 Prediction for Part 22 Maximum radiated power EIRP: 33.83 dBm (2415 mW) @ 824.2MHz Lowest limit for 850 MHz fixed operations (@20cm) where no routine evaluation is 2 2 required is § 1.1310: (f/1500)mW/cm =0.5495 mW/cm Calculated at distance of 20cm for reference antenna: Power density = 2415 / (4 x pi x 202) = 0.4808 mW/cm2 Result: Configuration complies with rules as power density is below MPE limit. Prediction for Part 24 Maximum radiated power EIRP: 31.71 dBm (1483mW) @1850.2 MHz Lowest limit for 1900 MHz fixed operations (@20cm) where no routine evaluation is 2 required is § 1.1310: 1 mW/cm Calculated at distance of 20cm: Power density = 1483 / (4 x pi x 202) = 0.295 mW/cm2 Result: Configuration complies with rules as power density is below MPE limit.

FCC-ID P5IC1K01 IC-ID (Industry Canada) 1478A-C1K01 Prediction for Part 15.247 Maximum radiated power EIRP: 25.59 dBm (362.2 mW) @MHz Lowest limit for 2400 MHz fixed operations (@20cm) where no routine evaluation is 2 required is § 1.1310: 1 mW/cm Calculated at distance of 20cm: Power density = 362.2 / (4 x pi x 202) = 0.0721 mW/cm2 Result: Configuration complies with rules as power density is below MPE limit. Prediction for Simultaneous Transmission The MPE limit was made using a separation distance of 1 cm to represent the worse case. % MPE Contour 45 40 80.0-100.0 35 30 60.0-80.0 Note: The 0% contour 25 surrounding the antennas identifies a 20 cm perimeter 20 40.0-60.0 surrounding all active 15 antennas 10 Distance Y (cm) 20.0-40.0 5 0 -5 0.0-20.0 -10 -15 -20 -25 -30 -35 -40 -45 -45 -40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 Distance X (cm)

FCC-ID P5IC1K01 IC-ID (Industry Canada) 1478A-C1K01 Date: 2009-03-16 Josie Sabado I am the author of this document Name: Josie Sabado Title: EMC Project Engineer Company: Cetecom Inc. Address: 411 Dixon Landing Rd, Milpitas, CA 95035, USA Phone: +1 408 586 6230 Email: Josephine.sabado@cetecomusa.com


Document Created: 2009-03-16 16:29:22
Document Modified: 2009-03-16 16:29:22
© 2025 FCC.report
This site is not affiliated with or endorsed by the FCC