transmit sound & image over a 915MHz LoRa link to a base station near your wifi. Currently set up to a send a frame from a serial TTL camera and a few seconds of sound from a microphone, but can be adapted for most data you want to send using LoRa directly.
I'm using two of the Heltec WiFi LoRa 32 v2, readily available on amazon etc. I'm able to get about 1km in range in a dense wooded place from this setup.
The camera I'm using is this one from Adafruit, but I'm looking for better options. The library is very fiddly, I had to slow down a bunch of serial calls to get it going on an ESP32, and the camera quality is low.
I'm using this MEMS i2s microphone as well.
local: esp-idf project for the device near a wifi link
remote: esp-idf project for the device out in a remote place
server: python web server to handle file uploads. Just run listen.py and update your local IP from local.cpp.
This is set up as an esp-idf project instead of Arduino, althought I'm using the Arduino component so that the camera package and Heltec LoRa package work fine. I have a lot of trouble with the Arduino IDE when there's more than one dev board connected and would rather work in a terminal anyway. I'm sure it's easy to port this back to Arduino if you want, it's simple enough.
You will want auth.h to exist in the local/main/ folder, with
#define WIFI_SSID your_ssid
#define WIFI_PASS your_password