How can we construct a long range communication device if classic communications devices (3G/4G, cell phones, internet) are disrupted ?
For example, if you want to contact relatives up to 40 kms away.
1st though: extend wifi with Yagi Antenna - https://www.instructables.com/Easy-to-Build-WIFI-24GHz-Yagi-Antenna/
2nd though: build a mesh network from house to house to extend communications ?
Didn't have tested or build now but will allow me time, at least for Yagi Antenna.
Does anybody have knowledge in this field ? (I own a PhD in microelectronics but that was 20 years ago but can help)
If someone is interested, we could: