While makers and carriers are talking up the benefits of 5G, Oppo is asking another question - what if there's no cell connection, no Wi-Fi or Bluetooth? It introduced a system called MeshTalk which can send data between devices up to 3km apart. We imagine that this is with a clear line of sight. Still, as the name suggests this is a mesh network - it can route the message through several nearby devices so it can reach its target, even if it's too far for a direct connection. MeshTalk uses a custom chip with enhanced sensitivity to achieve this long range communication. It's a...
Source: https://www.gsmarena.com/oppo_meshtalk_can_make_calls_and_send_texts_with_no_carrier_or_internet_connection-news-37791.php