When I searched for the impact of 4G and 5G frequency spectrum on health/medical sector/hospitals, I found good Japanese research by NTT Docomo about this topic and here I concluded the main points of the study and results.
Research Area
- Electromagnetic interference with medical devices is caused by radio waves emitted from mobile phones and smartphones so these radio communication devices can be further utilized in hospitals.
Technologies
- 4G and 5G
Main Radio Wave Specification
- 4G: 800MHz, 2GHz
- 5G: 3.7GHz, 4.8GHz and 28GHz.
Architecture
- 5G NSA.
The Research Study Test Scenario
The stronger the radio wave emitted to the medical device, the more likely electromagnetic interference will occur. For the basic test, we scanned all surfaces of the medical device while changing the direction of the antenna for each surface.
They were also tested when sensors and cables were connected to medical devices. When electromagnetic interference occurred, as an additional test, They gradually moved the antenna away from the medical device in intermittent mode and at the set transmission power to determine the distance at which the electromagnetic interference disappears (from now on referred to as “maximum impact distance”).
This test was conducted by irradiating various medical devices with 4G and 5G radio waves simultaneously emitted from antennas at different frequencies and modulations.
What is the Maximum Impact Distance
- The distance at which the electromagnetic interference disappears.
Test Results
The maximum impact distance when 4G radio waves in the 2 GHz band and 5G radio waves in the 3.7 GHz or 4.5 GHz band are transmitted simultaneously. In this case, the total transmission power of 4G and 5G radio waves is specified as less than 200 mW, so They compared the maximum impact distance for three patterns:
- 4G 200 mW only.
- 4G 100 mW + 5G 100 mW.
- 5G 200 mW only.
It was found that the maximum impact distance for the pattern (2), in which 4G and 5G radio waves were transmitted simultaneously, was no greater than either pattern (1) or (3), therefore They found that the maximum impact distance could be sufficiently obtained from patterns (1) and (3), in which 4G or 5G radio wave was transmitted independently at 200 mW.
The same results were obtained for the maximum impact distance when 4G modulation waves in the 800 MHz band were combined with 5G modulation waves in the 3.7 GHz or 4.5 GHz band.
Conclusion
The above results suggest that the impacts on medical devices by simultaneous 4G and 5G transmission can be estimated from the results of a single transmission only.
Also, in the research they tried using 5G in a 4G spectrum like 700MHz and 2GHz, and the conclusion was different technologies (modulation) did not cause a significant difference in the impact on medical devices or the maximum impact distance.
