Suggestion for Multinode 1Km Range RF Communication Module

Projects General Guidance
1

Hello, everyone! I am a beginer to RF communication. In my project I need to control several arduino from a single arduino. Also I need to send in 1Km range. Which module will be most reliable and cheap for this application?

Project Detail:
In my project one master Arduino will control several slave Arduino. Each slave Arduino is attached to a DC motor through a motor driver. Master Arduino will have button interface for each slave Arduino. If a button is pressed, corresponding slave will drive its motor for a specific amount of time. That's all!

Thanks!

2

Do you have a clear line of sight over the entire 1 km range, to every other Arduino?

3

jremington:
Do you have a clear line of sight over the entire 1 km range, to every other Arduino?

No! The project will be installed in a forest.

4

Then unless you have an amateur radio operator's license, and suitable radio modules, it is very difficult if not impossible.

5

You could take a look here.....

Normally one takes Instructables with a grain of salt but others who have looked at this system seem to think it could be ok.

6

APC220 radios are pretty good, but cost anywhere from $40 - $78 each, depending on where you get them from.
Its still a very difficult thing to do.
Id be inclined to try just 2 Hc-12 radios to see if they work at all in the forest, especially after its been raining, with the radios 1 Km apart.

7

If you are a beginner, start with simple modules like the NRF24L01 and learn to do short range point to point communications. Then you can start thinking about longer range, and networks.

8

Look at LoRa radios - considerable range. But a forest is a highly absorbtive environment.

Try it and see.

Allan

9

sajibfinix:
Hello, everyone! I am a beginer to RF communication

We can tell, your assuming (incorrectly) that your application is going to be easy and you provide no details.

LoRa is by a long margin the most capable system in this application area, but it does have its limitations.

I would expect LoRa to work at that distance, if you use a data rate of 100bps, you might get away with a higher rate though.

(I have done a fair bit of forest tramping while testing LoRa's capability as a lost model locator)

This is an advanced topic for a beginner, a good understanding of RF and antenna's is required to get an application to work relaibly in that environment.

Do you not think it a good idea to give us some clues as to what the application is, you may get far more realistic answers ?

You know the project, we can only guess.

10

srnet:
Do you not think it a good idea to give us some clues as to what the application is, you may get far more realistic answers ?

In my project one master Arduino will control several slave Arduino. Each slave Arduino is attached to a DC motor through a motor driver. Master Arduino will have button interface for each slave Arduino. If a button is pressed, corresponding slave will drive its motor for a specific amount of time. That's all!