How to ssh into a raspberry pi a middle of a field without wifi, ethernet, and usb?

Question

I have a raspberry pi on a drone and this drone is operated and tested in a middle of a field that does not have a wifi connection. I need to ssh into this raspberry pi from my laptop and I cannot use USB or Ethernet either since the raspberry pi is on a drone.

Wifi sharing from my mobile phone is not an option and has caused severe problems in the past. My idea is to make the raspberry pi into a router that does not actually connect to the internet through a modem, but just allows devices to connect to the raspberry pi. I only need my laptop to connect to it.

Essentially like how you connect your bluetooth earbuds to your phone but imagine via wifi.

I have tried tutorials that assume the raspberry pi will act as an actual wireless access point that connects to your home network. I don't need internet access, but just a direct connection to the raspberry pi.

Answer 1

Another possibility for remote console access to a Pi 3 might be rfcomm over Bluetooth.

Answer 2

Not sure how well this wold work, but using Digi XBee modules you could communicate with the RPi without wifi and directly using serial communications. You would need two Digi Xbee's, one connected to the Serial of the RPi and the other to your computer.

Understanding how to connect to RPi serial using the GPIO pins https://elinux.org/RPi_Serial_Connection

Additional information to get you started on XBee https://www.digi.com/resources/documentation/Digidocs/90001456-13/concepts/c_serial_communication.htm

Initial concern would be the quantity of data that needs to be transferred and power requirements.

Answer 3

As you say you can use an access point on the RasPi. I would suggest to use it. It has the advantage that you also can use it to remotely control the flying drone. You only need a simple access point without any other functionality like routing or bridging to another hotspot. Raspbian has everything "built-in" for an access point, you do not need any additional programs. Just configure it. How to do it you can look at Setting up a Raspberry Pi as an access point - the easy way. Just follow the instructions in section Setting up a stand alone access point.