I'm not very experienced in wireless space.
I wish to communicate with an Arduino device stationed at the back of my property, roughly 1500 meters away. I have line of sight, although blowing trees may temporarily get in the way.
Running cable is not feasible with regard to cost, distance and terrain.
I have no problem with a directional antenna on my end, but that is less appealing at the device's end as I want to keep it as light, small, and low-power as possible. If directional at both ends is required, I can make it work.
Wifi? Zigbee? Certainly not bluetooth. Cellular? Something else I should look at?
At the remote side, my hope is that it can run on battery alone, for at least the order of months. I currently have it running at ultra low power of only 54 uA for all but 9.6 minutes of each day. Roughly 100mA for those 9.6 minutes, while it is gathering sensor data and making decisions on what data to send. As it is, on battery I can run it for nearly 10 months on a 5Ah battery. I have no idea how much the wireless equipment will impact that. If I need to add a solar panel, it wouldn't be the end if the world. Still, energy efficiency is a consideration.
Best Answer
Also consider LoRa sub-G RF modules: long-range, battery powered (ULP), ISM band, affordable price. Many modules are available (though chipset mostly by Semtech, seems also Microchip is offering recently). Quick search returns:
https://www.cooking-hacks.com/documentation/tutorials/extreme-range-lora-sx1272-module-shield-arduino-raspberry-pi-intel-galileo/
http://modtronix.com/inair9.html
http://www.seeedstudio.com/s/LoRa.html
https://www.loriot.io/modems.html