ZEB 15707-02 MPE Report Rev 2

FCC ID: UZ7ATR7000

RF Exposure Info

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FCCID_4017673

Maximum Permissible Exposure Evaluation For the ZEBRA TECHNOLOGIES CORPORATION RFID Reader ATR7000 FCC ID: UZ7ATR7000 September 24, 2018 WLL Report: 15707-02 Rev 2 Prepared for: ZEBRA TECHNOLOGIES CORPORATION 1 ZEBRA PLAZA HOLTSVILLE, NY 11742 Prepared by: WASHINGTON LABORATORIES, LTD. 7560 LINDBERGH DRIVE GAITHERSBURG, MARYLAND 20879 Certificates and reports shall not be reproduced except in full, without the written permission of Washington Labs, Limited.

Zebra Tech RF Exposure Test Report ATR7000 August 2018 Maximum Permissible Exposure Evaluation For the Error! Reference source not found. RFID Reader ATR7000 WLL Report: 15707-02 Rev 2 Re-Issued September 14, 2018 Prepared by: Nikolas Allen EMC Engineer Reviewed by: John P. Repella Manager, EMC & Wireless Services WLL Report# 15707-02 Rev 2 - ii - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 Abstract This report has been prepared on behalf of Error! Reference source not found. ATR7000 to document the findings of the maximum permissible exposure evaluation on the Error! Reference source not found. ATR7000. The purpose of this evaluation is to establish a minimum safe distance as per the RF exposure requirements as defined in FCC §1.1307 & §1.1310. This report documents the results of testing to the requirements of: • CFR Title 47 Volume 1 Practice and Procedure; (1.1307) Environmental Assessments The Evaluation was performed by Washington Laboratories, Ltd, 7560 Lindbergh Drive, Gaithersburg, MD 20879. Washington Laboratories, Ltd. has been accepted as an EMC Conformity Assessment Body (CAB) under the United States/European Union Memorandum of Agreement. Washington Laboratories, Ltd. is accredited by ANAB under Testing Certificate AT-1448. Revision History Reason Date Rev 0 Initial Release August 30, 2018 Rev 1 Report updated to address comments September 5, 2018 Rev 2 Added Power Density at Minimum distance September 24, 2018 WLL Report# 15707-02 Rev 2 - iii - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 Table of Contents Abstract ................................................................................................................................................................... iii 1 Introduction ................................................................................................................................................ 1 2 Requirements .............................................................................................................................................. 1 2.1 Transmitter Categories ............................................................................................................................. 1 2.2 Exposure Categories ................................................................................................................................ 1 3 Device Summary ......................................................................................................................................... 4 3.1 Antenna Array Discussion ....................................................................................................................... 4 4 Radio Frequency Radiation Exposure Evaluation .................................................................................. 5 List of Tables Table 1: MPE Limits ..................................................................................................................................................2 Table 2: Device Summary of the ATR7000 ...............................................................................................................4 Table 3: Transmitter MPE Calculation Summary ......................................................................................................5 WLL Report# 15707-02 Rev 2 - iv - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 1 Introduction This report has been prepared on behalf of Error! Reference source not found.?? ATR7000 Transmitter to show compliance with the RF exposure requirements as defined in FCC §1.1307. Testing supporting this evaluation was performed at Washington Laboratories, Ltd, 7560 Lindbergh Drive, Gaithersburg, MD 20879. Washington Laboratories, Ltd. has been accepted as an EMC Conformity Assessment Body (CAB) under the United States/European Union Memorandum of Agreement. Washington Laboratories, Ltd. is accredited with ANAB under Testing Certificate AT- 1448. 2 Requirements Three different categories of transmitters are defined by the FCC in OET Bulletin 65. These categories are fixed installation, mobile, and portable. Additionally, the FCC categorizes the use of the devices based on the user’s awareness and the ability to exercise control over his or her exposure. The two categories are defined as Occupational/Controlled Exposure and General Population/Uncontrolled Exposure. 2.1 Transmitter Categories 2.1.1 Fixed Installations A fixed location means that the device, including its antenna, is physically secured at a permanent location and is not able to be easily moved to another location. Additionally, distance to humans from the antenna is maintained to at least 2 meters. 2.1.2 Mobile Devices A mobile device is defined as a transmitting device designed to be used in other than fixed locations and to be generally used in such a way that a separation distance of at least 20 centimeters is normally maintained between the transmitter's radiating structures and the body of the user or nearby persons. Transmitters designed to be used by consumers or workers that can be easily re-located, such as a wireless modem operating in a laptop computer, are considered mobile devices if they meet the 20centimeter separation requirement. The FCC rules for evaluating mobile devices for RF compliance are found in 47 CFR §2.1091. 2.1.3 Portable Devices A portable device is defined as a transmitting device designed to be used so that the radiating structure(s) of the device is/are within 20 centimeters of the body of the user. Portable device requirements are found in Section 2.1093 of the FCC's Rules (47 CFR§2.1093). 2.2 Exposure Categories The limits for exposure are determined by the type of situation in which the individual is exposed. Table 1 lists the limits for the particular environment. 2.2.1 Occupational/Controlled Exposure In general, occupational/controlled exposure limits are applicable to situations in which persons are exposed as a consequence of their employment, who have been made fully aware of the potential for WLL Report #15707-02 Rev 2 - Page 1 of 5 - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 exposure and can exercise control over their exposure. This exposure category is also applicable when the exposure is of a transient nature due to incidental passage through a location where the exposure levels may be higher than the general population/uncontrolled limits, but the exposed person is fully aware of the potential for exposure and can exercise control over his or her exposure by leaving the area or by some other appropriate means. Awareness of the potential for RF exposure in a workplace or similar environment can be provided through specific training as part of a RF safety program. If appropriate, warning signs and labels can also be used to establish such awareness by providing prominent information on the risk of potential exposure and instructions on methods to minimize such exposure risks. 2.2.2 General Population/Uncontrolled Exposure The general population / uncontrolled exposure limits are applicable to situations in which the general public may be exposed or in which persons who are exposed as a consequence of their employment may not be made fully aware of the potential for exposure or cannot exercise control over their exposure. Members of the general public would come under this category when exposure is not employment- related; for example, in the case of a wireless transmitter that exposes persons in its vicinity. Warning labels placed on low-power consumer devices such as cellular telephones are not considered sufficient to allow the device to be considered under the occupational/controlled category and the general population/uncontrolled exposure limits apply to these devices. Table 1: FCC MPE Limits Averaging Frequency range Electric field strength Magnetic field strength Power density (mW/cm2) time (MHz) (V/m) (A/m) (minutes) (A) Limits for Occupational/Controlled Exposures 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 6 300–1500 N/A N/A f/300 6 1500–100,000 N/A N/A 5 6 (B) Limits for General Population/Uncontrolled Exposure 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 N/A N/A f/1500 30 1500–100,000 N/A N/A 1 30 WLL Report #15707-02 Rev 2 - Page 2 of 5 - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 Table 2: ISED MPE Limits (General Population, Uncontrolled Exposure) Frequency Electric Field Magnetic Field Power Density Reference Period Range (MHz) (V/m rms) (A/m rms) (W/m2) (minutes) 0.003-1021 83 90 - Instantaneous* 0.1-10 - 0.73/ ƒ - 6** 1.1-10 87/ ƒ 0.5 - - 6** 10-20 27.46 0.0728 2 6 20-48 58.07/ ƒ 0.25 0.1540/ ƒ 0.25 8.944/ ƒ 0.5 6 48-300 22.06 0.05852 1.291 6 300-6000 3.142 ƒ 0.3417 0.008335 ƒ 0.3417 0.02619ƒ0.6834 6 6000-15000 61.4 0.163 10 6 15000-150000 61.4 0.163 10 616000/ ƒ 1.2 150000-300000 0.158 ƒ 0.5 4.21 x 10-4 ƒ 0.5 6.67 x 10-5 ƒ 616000/ ƒ 1.2 Note: ƒ is frequency in MHz. *Based on nerve stimulation (NS). ** Based on specific absorption rate (SAR). WLL Report #15707-02 Rev 2 - Page 3 of 5 - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 3 Device Summary Table 1 below summarizes the criteria used to evaluate the ATR7000. Table 3: Device Summary of the ATR7000 Model Evaluated: RFID Reader ATR7000 Transmitter Category: Fixed Installation Exposure Category: General Population Antenna Gain: 12.5dBi Power Output (dBm): 211.33mW (23.25dBm) Evaluation Distance: 20cm Frequency Range: 902 – 928 MHz FCC Limit: 0.618mW/cm2 ISED Limit: 0.28024mW/cm2 FCC Safe Distance 22cm ISED Safe Distance 32.7cm 3.1 Antenna Array Discussion Accounting for the cross-polarization of the structure the directional gain of the antenna array is computed as follows: GArray (dBi) = (4.0 - 3.0) + 10 log (14) = 12.5 dBi Therefore, to achieve a desired level of radiated power PTX,EIRP (dBm), the conducted power delivered to the antennas is controlled such that Therefore, to achieve a desired level of radiated power PTX,EIRP (dBm), the conducted power delivered to the antennas is controlled such that: PConducted (dBm) = PTX, EIRP (dBm) - 12.5 To ensure that the radiated power never exceeds the Part 15 limit of +36 dBm EIRP when taking manufacturing tolerances into account, the internal software of the ATR7000 limits PTX, EIRP used in the above formula to 35.3 dBm when calculating the amount of conducted power to deliver to the antenna array. Note that a tolerance was also included in the gain of each element. When directional gain of the antenna array GArray (dBi) was computed to be 12.5 dB, the 4 dBic used in the formula was the maximum total gain. The typical element gain is 3.3 dBic and not 4 dBic. WLL Report #15707-02 Rev 2 - Page 4 of 5 - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 4 Radio Frequency Radiation Exposure Evaluation The highest RF output power of the unit was measured and recorded. According to §1.1310 of the FCC rules, the power density limit for General Population/Uncontrolled Exposure is = f/1500(0.618mW/cm2 ) where f is the frequency of concern in MHz. The power density limit for General Population/Uncontrolled Exposure for ISED is = 0.02619ƒ0.6834 (0.280mW/cm2 ) where f is the frequency of concern in MHz. The MPE shall be calculated at 20cm to show compliance with the power density limit. The following formula was used to calculate the Power Density: PG S= 4R 2 Where: S = Power Density P = Output Power at the Antenna Terminals G = Gain of Transmit Antenna (linear gain-isotropic) R = Distance from Transmitting Antenna Table 4: Transmitter FCC MPE Calculation Summary One Transmitter Frequency 927.5 MHz Limit 0.618 mW/cm^2 Distance (cm), R = 20 cm Power (dBm), P = 23.25 dBm TX Ant Gain (dBi), G = 12.5 dBi Power Density: 0.75 mW/cm^2 Separation>20 cm Minimum Distance: 22.0 cm Power Density at minimum Distance: S=(10^(23.25/10))*(10^(12.5/10))/(4*3.14*0.222 ) S=(211*17.8)/0.608 S= 6177 mW/m2 S= 0.6177 mW/cm2 WLL Report #15707-02 Rev 2 - Page 5 of 5 - © 2018 Washington Laboratories, Ltd.

Zebra RF Exposure Test Report ATR7000 August 2018 Table 5: Transmitter ISED MPE Calculation Summary One Transmitter Frequency 927.5 MHz Limit 0.280 mW/cm^2 Distance (cm), R = 20 cm Power (dBm), P = 23.25 dBm TX Ant Gain (dBi), G = 12.5 dBi Power Density: 0.75 mW/cm^2 Separation>20 cm Minimum Distance: 32.7 cm Power Density at minimum Distance: S=(10^(23.25/10))*(10^(12.5/10))/(4*3.14*0.3272 ) S=(211*17.8)/1.343 S= 2796.58 mW/m2 S= 0.2797 mW/cm2 WLL Report #15707-02 Rev 2 - Page 6 of 5 - © 2018 Washington Laboratories, Ltd.


Document Created: 2018-09-24 13:37:02
Document Modified: 2018-09-24 13:37:02
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