RF Exposure

FCC ID: LDK102090P

RF Exposure Info

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FCCID_2886337

EDCS-1539153 RF Exposure Study - Engineering Analysis per FCC 2.1091 AIR-CAP1532I-B-K9 Cisco Aironet 802.11n Dual Band Mesh Access Points FCC ID: LDK102090P Prepared By: Cisco Systems Inc 170 West Tasman San Jose, CA 95134 USA

EDCS-1539153 1.0: Attestation Statement of Compliance The Cisco AIR-CAP1532I-B-K9, 802.11N radio has been evaluated for Maximum Permissible Exposure in compliance with 47 Code of Federal Regulations 2.1091. The evaluation was in accordance with methodology as referenced in FCC Bulletin OET 65C (rev 01-01). This report serves as the additional technical analysis of the Cisco radio modules This study addresses the addition of an additional pair of transmitters using the data derived in the afore mentioned report # 2.4GHz DTS report EDCS#- 1280939 5GHz UNII-1 report EDCS-1539150 5GHz UNII-2 report EDCS-1282499 5GHz UNII-2ext reports EDCS-1282501, 1539151 5GHz UNII-3 report EDCS-1539152 The limits used for this evaluation are in line with the recommendations of the World Health Organizations (WHO) International Committee on Non Ionizing Radiation Protection (ICNIRP) as well as the American National Standards Institute (ANSI) C95.1. The limits chosen are of General Population/Uncontrolled Exposure. the following case scenarios were used : 2.4GHz WLAN 5GHz WLAN This device must be installed to provide a separation distance of at least 20 cm from all persons. Installers must be provided with antenna installation and transmitter operating conditions for satisfying RF exposure compliance. Based on the study this case scenario, the General Population/Uncontrolled Exposure and the minimum recommended distance is around 20cm (7.8 inches) from the antenna. Jose Aguirre Cisco Systems Inc Corporate Compliance and Certifications 125 West Tasman Drive San Jose, CA 95134 Email: joaguirr@cisco.com

EDCS-1539153 2.0 EUT Description. The 1532I Series Cisco Aironet 802.11n Dual Band Mesh Access Points support the following modes of operation. The modes are further defined in the radio Theory of Operation. The modes included in this report represent the worst case data for all modes. Non HT/VHT-20, One Antenna, 6 to 54 Mbps Non HT/VHT-20, Two Antennas, 6 to 54 Mbps HT/VHT-20, One Antenna, M0 to M7 HT/VHT-20, Two Antennas, M0 to M15 HT/VHT-20 STBC, Two Antennas, M0 to M7 Non HT/VHT-40 Duplicate, One Antenna, 6-54 Mbps Non HT/VHT-40 Duplicate, Two Antennas, 6-54 Mbps HT/VHT-40, One Antenna, M0 to M7 HT/VHT-40, Two Antennas, M0 to M15 HT/VHT-40 STBC, Two Antennas, M0 to M7 The following antennas are supported by this product series. The data included in this report represent the worst case data for all antennas. Antenna Gain Frequency Part Number Antenna Type (dBi) 2.4/5 GHz Internal Dual-resonant Omni 3/5

EDCS-1539153 3.0 Methodology All calculations were made in accordance with ANSI C95.1, and FCC OET 65C. 4.0 Technical Requirements 4.1 Single Band Operation – Limits FCC Limits for Maximum Permissible Exposure (MPE) (A) Limits for Occupational/Controlled Exposure Frequency Electric Field Magnetic Field Power Density Averaging Time Range Strength (E) Strength (H) (S) |E|2, |H|2 or S (MHz) (V/m) (A/m) (mW/cm2) (minutes) 0.3-3.0 614 1.63 (100)* 6 3.0-30 1842/f 4.89/f (900/f2)* 6 30-300 61.4 0.163 1.0 6 300-1500 -- -- f/300 6 1500-100,000 -- -- 5 6 (B) Limits for General Population/Uncontrolled Exposure Frequency Electric Field Magnetic Field Power Density Averaging Time Range Strength (E) Strength (H) (S) |E|2, |H|2 or S (MHz) (V/m) (A/m) (mW/cm2) (minutes) 0.3-1.34 614 1.63 (100)* 30 1.34-30 824/f 2.19/f (180/f2)* 30 30-300 27.5 0.073 0.2 30 300-1500 -- -- f/1500 30 1500-100,000 -- -- 1.0 30 f = frequency in MHz *Plane-wave equivalent power density NOTE 1: See Section 1 for discussion of exposure categories. NOTE 2: The averaging time for General Population/Uncontrolled exposure to fixed transmitters is not applicable for mobile and portable transmitters. See 47 CFR §§2.1091 and 2.1093 on source-based time-averaging requirements for mobile and portable transmitters.

EDCS-1539153 5.0 Calculations Given E=√(30*P*G)/d and S=E^2/3770 where E=Field Strength in Volts/meter P=Power in Watts G=Numeric Antenna Gain d=Distance in meters S=Power Density in mW/cm^2 Combine equations and rearrange the terms to express the distance as a function of the remaining variables: d=√((30*P*G)/(3770*S)) Changing to units of power in mW and distance in cm, using: P(mW)=P(W)/1000 d(cm)=100*d(m) yields d=100*√((30*(P/1000)*G)/(3770*S)) d=0.282*√(P*G/S) where d=Distance in cm P=Power in mW G=Numeric Antenna Gain S=Power Density in mW/cm^2 Substituting the logarithmic form of power and gain using: P(mW)=10^(P(dBm)/10) G(numeric)=10^(G(dBi)/10) yields d=0.282*10^((P+G)/20)/√S Equation (1) and s=((0.282*10^((P+G)/20))/d)^2 Equation (2) where d=MPE distance in cm P=Power in dBm G=Antenna Gain in dBi S=Power Density in mW/cm^2

EDCS-1539153 6.0 Results Equation (1) and the measured peak power are used to calculate the MPE distance. Note that for mobile or fixed location transmitters such as an access point, the minimum separation distance is 20 cm even if the calculations indicate that the MPE distance may be less. S=1mW/cm^2 maximum. The highest supported antenna gain is 5 dBi (8dBi with beamforming). Using the peak power levels recorded in the test report along with Equation 1 above, the MPE distances are calculated as follows. MPE Calculations: Peak Power Transmit Antenna MPE Density Power Gain Distance Limit Margin Band (mW/cm^2) (dBm) (dBi) (cm) (cm) (cm) 2.4GHz DTS 1 28.6 3 10.72 20 9.28 5GHz UNII-1 1 20.9 5 5.56 20 14.44 5GHz UNII-2 1 21.2 5 5.76 20 14.24 5GHz UNII-2e 1 23.1 5 7.17 20 12.83 5GHz UNII-3 1 25.2 5 9.13 20 10.87 To maintain compliance, installations will assure a separation distance of at least 20cm. Using Equation 2, the MPE levels (s) at 20 cm are calculated as follows: Peak MPE Transmit Antenna Power Distance Power Gain Density Limit Margin Band (cm) (dBm) (dBi) (mW/cm^2) (mW/cm^2) (mW/cm^2) 2.4GHz DTS 20 28.6 3 0.29 1 0.71 5GHz UNII-1 20 20.9 5 0.08 1 0.92 5GHz UNII-2 20 21.2 5 0.08 1 0.92 5GHz UNII-2e 20 23.1 5 0.13 1 0.87 5GHz UNII-3 20 25.2 5 0.21 1 0.79 Calculations with additional transmitters The AIR-CAP1532I-B-K9 Cisco 802.11N Radio support operation with 2.4GHz WLAN & 5GHz WLAN. Scenerio 1 : 2.4GHz WLAN ( Highest power) 5GHz WLAN (Highest power) TX1 + TX6 = % of standard ( 0.29) + (0.21 ) = 0.5 D (estimate) = 20* % D = 14.1cm which is less than 20cm recommended The configuration above co-location calculation is for General Population/Uncontrolled exposure. The minimum distance recommended is 20cm (8 inches) when all antennas are within 20cm of each other.

EDCS-1539153 References American National Standards Institute (ANSI), "Safety Levels with Respect to Human Exposure to Radio Frequency Electromagnetic Fields, 3 kHz to 300 GHz," ANSI/IEEE C95.1-1992 (previously issued as IEEE C95.1-1991). Copyright 1992 by the Institute of Electrical and Electronics Engineers, Inc. (IEEE), New York, N.Y. 10017. For copies contact the IEEE: 1-800-678-4333 or 1-908-981-1393. American National Standards Institute (ANSI), "Recommended Practice for the Measurement of Potentially Hazardous Electromagnetic Fields - RF and Microwave”. ANSI/IEEE C95.3-1992. Copyright 1992, The Institute of Electrical and Electronics Engineers, Inc. (IEEE), New York, NY 10017. For copies contact the IEEE: 1-800-678-4333 or 1-908-981-1393. FCC OET 65C Evaluating Compliance with FCC Guidelines for Human Exposure to RF Fields from 9KHz to 40 Ghz


Document Created: 2017-11-16 09:31:57
Document Modified: 2017-11-16 09:31:57
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