Cellphone radiation and SAR
The authorities have set a SAR value of a maximum of 2 Watts per kilo as the maximum permissible SAR value. Link to STUK. Modern phones have a maximum output of about 250Mw (24dBm) but the SAR value can vary considerably depending on the size of the antenna, material in the mobile phone etc.
Even though you have adequate mobile coverage, the signal from the mobile phone must travel through walls and ceilings several kilometers to the base station. This means that the phone transmits at high power despite adequate cellular coverage.
When installing a repeater and mobile signal amplifier, the signal from the mobile phone only needs to reach the indoor antenna. The repeater amplifies the signal and sends it to the operator's base station. This means that the mobile phone reduces the output power to the lowest possible, which is several 1000 times lower than the maximum output power.
A repeater also radiates but considerably less. Usually, our smaller repeater models are at an output power of 0-10dBm which corresponds to 1Mw - 10Mw which is 25-250 times lower output power than the mobile phone. In addition, many meters from the repeater's internal antenna are located so that the radiation becomes extremely low.
Another advantage of repeater installation is that when the mobile phone draws more power to a minimum, you save battery and you do not need to charge as often. Example: Here we see the difference in the output of the mobile phone with repeater and without repeater respectively. In Figure 1 we see RX / TX with one of our smallest repeaters turned on. We see that the received signal strength is -64dBm and the transmitter power of the phone is only -37dBm (0.0002 milliwatts) In figure 2 we see RX / TX with repeater turned off. The received signal strength drops to -95dBm and the phone pulls up the output power to the full + 19dBm (79.43 milliwatts) to reach the base station. In this case, the power output from the mobile phone will be about 4000 times lower with a repeater installed.