Maximum Permissible Exposure Evaluation
Company: CTC Laboratories, Inc.
Address: 2/F., Building 1 and 1-2/F., Building 2, Jiaquan Building, Guanlan High-Tech Park, Longhua District, Shenzhen, Guangdong, China
Contact: Tel: +86-755-27521059, Fax: +86-755-27521011
Website: http://www.sz-ctc.org.cn
FCC ID: 2AGKB-KM2PLUS-D
Introduction
This evaluation is conducted according to FCC 1.1310, which specifies the criteria for assessing the environmental impact of human exposure to radio frequency (RF) radiation as outlined in §1.1307(b).
EUT Specification
| Product Name: | Set Top Box |
|---|---|
| Trade Mark: | MECOOL |
| Model/Type Reference: | KM2 PLUS D |
| Listed Model(s): | KM2 PLUS DELUXE, Lumia, HP4423, HP4422, HP4426, HP44J, Ooredoo tv, Leap-S4 |
| Model Differences: | All listed models are identical in PCB layout and electrical circuit; differences lie in model numbers. |
| Frequency Band (Operating): |
|
| Device Category: | Portable (<5mm separation) |
| Exposure Classification: | General Population/Uncontrolled exposure (S=1mW/cm²) |
| Antenna Diversity: | Multiple antennas (Tx diversity, Rx diversity, Tx/Rx diversity) |
| Antenna Gain (Max): |
|
| Evaluation Applied: | MPE Evaluation (SAR Evaluation) |
Limits for Maximum Permissible Exposure (MPE)
The following table outlines the MPE limits for different frequency ranges and exposure classifications.
Limits for Occupational/Controlled Exposure
| Frequency Range (MHz) | Electric Field Strength (V/m) | Magnetic Field Strength (A/m) | Power Density (mW/cm²) | Averaging Time (minutes) |
|---|---|---|---|---|
| 300-1500 | -- | -- | f/300 | <6 |
| 1500-100000 | -- | -- | 5 | <6 |
Limits for General Population/Uncontrolled Exposure
| Frequency Range (MHz) | Electric Field Strength (V/m) | Magnetic Field Strength (A/m) | Power Density (mW/cm²) | Averaging Time (minutes) |
|---|---|---|---|---|
| 300-1500 | -- | -- | f/1500 | <30 |
| 1500-100000 | -- | -- | 1 | <30 |
Calculation Method
The Friis transmission formula is used for calculation: Pd=(Pout*G)/(4*Pi*R²)
Where:
- Pd = Power density in mW/cm²
- Pout = output power to antenna in mW
- G = gain of antenna in linear scale
- Pi = 3.1416
- R = distance between observation point and center of the radiator in cm
The MPE limit for General Population/Uncontrolled Exposure is 1mW/cm². By knowing the maximum antenna gain and total power input, the distance at which the MPE limit is reached can be determined.
Measurement Result
| Mode | Frequency (MHz) | Antenna Gain (dBi) | Maximum Power (dBm) | Tune Up Tolerance (dB) | Max. Tune Up Power (dBm) | Power Density at 20cm (mW/cm²) | Limit (mW/cm²) |
|---|---|---|---|---|---|---|---|
| BT/EDR | 2480 | 1.87 | 5.518 | ±1 | 6 | 0.00122 | 1 |
| BLE 1M | 2402 | 1.87 | 4.033 | ±1 | 5 | 0.00097 | 1 |
| WLAN 802.11b | 2462 | 2.3 | 17.787 | ±1 | 18 | 0.02132 | 1 |
| RLAN U-NII-1 802.11n (HT20) | 5180 | 1.7 | 18.5 | ±1 | 19 | 0.02684 | 1 |
| RLAN U-NII-2A 802.11ac (VHT40) | 5310 | 1.7 | 18.77 | ±1 | 19 | 0.02684 | 1 |
| RLAN U-NII-2C 802.11n (HT40) | 5670 | 1.7 | 18.79 | ±1 | 19 | 0.02684 | 1 |
| RLAN U-NII-3 802.11ax (HE40) | 5755 | 1.7 | 18.73 | ±1 | 19 | 0.02684 | 1 |
The WLAN and BT can transmit simultaneously.
| Power density at 20cm (mW/cm²) | Power density at 20cm (mW/cm²) | Total Power density at 20cm (mW/cm²) | Power density Limit (mW/cm²) | ||
|---|---|---|---|---|---|
| WLAN | 0.00122 | BT | 0.02684 | 0.02806 | 1 |
Notes:
- Calculations are performed in the worst-case mode.
- Maximum Tune Up Power is declared by the manufacturer and used for calculations.
- For a more detailed description of features, please refer to the RF Test Report.
