ESPRESSIF SYSTEMS ESPWROOM02 Wi-Fi Internet of Things Module User Manual RF Exposure Info
ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD Wi-Fi Internet of Things Module RF Exposure Info
Contents
- 1. RF Exposure Info
- 2. User Manual
RF Exposure Info
Report No.: RXA1503-0042MPE01 Page 1 of 5
:
MPE REPORT
Product Name Wi-Fi Internet of Things Module
Model ESP-WROOM-02
Brand Name WROOM
FCC ID 2AC7Z-ESPWROOM02
Applicant ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD
Manufacturer ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD
Date of issue April 10, 2015
Approved by
Kai Xu
Director
Revised by
Jiangpeng Lan
SAR Manager
Performed by
Liang Ye
SAR Engineer
Test By
Company: TA Technology (Shanghai) Co., Ltd.
Address: No.145, Jintang Rd, Tangzhen Industry Park, Pudong Shanghai,China
Contact: Xu Kai
Telephone: +86-021-50791141/2/3
Fax: +86-021-50791141/2/3-8000
Website: http://www.ta-shanghai.com
E-mail: yangweizhong@ta-shanghai.com
TA Technology (Shanghai)Co.,Ltd.
Test Report
Report No.: RXA1503-0042MPE01 Page 2 of 5
Maximum Permissible Exposure
Type of EUT: Wi-Fi Internet of Things Module
FCC ID: 2AC7Z-ESPWROOM02
Manufacturer: ESPRESSIF SYSTEMS (SHANGHAI) PTE LTD
Model: ESP-WROOM-02
Maximum conducted output power (measured) and antenna Gain:
Band Output Power(dBm)
802.11b 22.23
802.11g 21.57
802.11n(20M) 22.04
According to section 1.1310 of FCC 47 CFR Part 1, limits for maximum permissible exposure (MPE)
are as following
Band maximum tune up procedure
(dBm)
Antenna Gain
(dBi)
802.11b 23 2
802.11g 23 2
802.11n(20M) 23.5 2
TA Technology (Shanghai)Co.,Ltd.
Test Report
Report No.: RXA1503-0042MPE01 Page 3 of 5
Note1. Occupational/controlled limits apply in situations in which persons are exposed as a consequence of their
employment provided those persons are fully aware of the potential for exposure and can exercise control
over their exposure. Limits for occupational/controlled exposure also apply in situations when an individual
is transient through a location where occupational / controlled limits apply provided he or she is made aware
of the potential for exposure.
Note2: General population/uncontrolled exposures apply in situations in which the general public may be exposed,
or in which persons that are exposed as a consequence of their employment may not be fully aware of the
potential for exposure or can not exercise control over their exposure.
TA Technology (Shanghai)Co.,Ltd.
Test Report
Report No.: RXA1503-0042MPE01 Page 4 of 5
The maximum permissible exposure for 300~1500MHz is f/1500, 1500~100,000MHz is f/1500.So
IMPORTANT NOTE: To comply with the FCC RF exposure compliance requirements, the antenna(s)
used for this transmitter must be installed to provide a separation distance of at least 20 cm from all
persons and must not be co-located or operating in conjunction with any other antenna or transmitter. No
change to the antenna or the device is permitted. Any change to the antenna or the device could result in
the device exceeding the RF exposure requirements and void user’s authority to operate the device.
Band The maximum permissible exposure
802.11b/g/n 1 mW/cm²
TA Technology (Shanghai)Co.,Ltd.
Test Report
Report No.: RXA1503-0042MPE01 Page 5 of 5
RF Exposure Calculations:
The following information provides the minimum separation distance for the highest gain antenna provided.
This calculation is based on the conducted power, considering maximum power and antenna gain. The
formula shown in KDB 865664 D01 is used in the calculation.
Equation from KDB 865664 D01, Edition 97-01 is:
S= PG / 4∏R2
where: S = power density (in appropriate units, e.g. mW/cm2)
P = Time-average maximum tune up procedure (in appropriate units, e.g., mW)
G = the numeric gain of the antenna
R = distance to the center of radiation of the antenna (20 cm = limit for MPE)
So, the numeric gain (G) of the antenna with a gain specified in dB is determined by
Numeric gain (G)=10^(antenna gain/10)=10^(2/10)=1.58 dB
802.11b PG = 23dBm+ (1.58dB) =24.58dBm=287mW
802.11g PG = 23dBm+ (1.58dB) =24.58dBm= 287mW
802.11n(20M) PG = 23.5dBm+(1.58dB)=25.08dBm= 322mW
R =20 cm
∏= 3.1416
Solving for S, the power density at 20 cm is
Band Test Result (mW/cm2) Limit Value (mW/cm2)
802.11b 0.06
1 mW/cm²
802.11g 0.06
1 mW/cm²
802.11n(20M) 0.06 1 mW/cm²
Note: For mobile or fixed location transmitters, minimum separation distance is 20cm, even if calculations
indicate MPE distance is less.