RE: BLE Link Drops When Body Blocks Line-of-Sight Between nRF52840 Devices

Amanda Hsieh — Tue, 17 Jun 2025 17:54:08 GMT

That's correct.

RE: BLE Link Drops When Body Blocks Line-of-Sight Between nRF52840 Devices

Andrea Verdecchia — Tue, 17 Jun 2025 08:03:23 GMT

Okay, that’s what I thought. At this point, I assume the problem also occurs when using WiFi, or am I wrong?

RE: BLE Link Drops When Body Blocks Line-of-Sight Between nRF52840 Devices

Amanda Hsieh — Thu, 12 Jun 2025 13:57:52 GMT

Hi,

Yes, communication between two devices using nRF52840-based modules can be easily disrupted by the human body, particularly at the 2.4 GHz frequency. Human tissue significantly attenuates 2.4 GHz signals, a limitation well-documented in Taking a deeper dive into Bluetooth 5. It noted that "the only major obstacle usually being the human body (although that is a considerable obstacle at 2.4 GHz)," which is why most Bluetooth applications are limited to around 10 meters in range.

Indoors, reflections off walls and objects can help maintain signal integrity even when obstacles are present. However, outdoors, where reflective surfaces are minimal, the signal is more likely to be blocked when the human body is between the devices.

Your observation that the link fails immediately when your body obstructs the path, even at close range, aligns with typical 2.4 GHz propagation behavior. This is a known physical limitation of the frequency band, but it is not necessarily an issue with your board or design. If performance is acceptable indoors but unreliable outdoors under these conditions, the likely cause is the absence of multipath reflection, not faulty hardware.

Regards,
Amanda H.