STMicroelectronics has released a paper describing ways to combine Bluetooth LE, accelerometers and sub-GHz Sigfox comms in a wearable social distancing node, designed to work with similar nodes. It uses non-connecting Bluetooth modes, measuring signal strength to estimate the proximity of similar devices in real time – acting on three adjustable  virtual ranges: safe (>3m), pre-alert (3m) ...

This story continues at ST moots ways to use Bluetooth wearables for social distancing

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