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LoRa technology was developed by a company called Semtech and it is a new wireless protocol designed specifically for long-range, low-power communications. LoRa stands for Long Range Radio and is mainly targeted for M2M and IoT (internet of things) networks. This technology will enable public or multi-tenant networks to connect a number of applications running on the same network [^digikey-lora]. In the US, LoRa communication works on 915 Mhz, which is a license free spectrum.

For different types of arduinoArduino, we can use a long -range transciever transceiver LoRa shield called the [Dragino shield](https://wiki.dragino.com/index.php?title=Lora_Shield)[^dragino-lora].

## Set LoRaFor a large amount of differently placed sensors and devices, it is recommended to set up a LoRaWAN network. However, if you seek to establish simple device-to-device communication for a separate system, LoRa on your laptopwith the RadioHead library works great.

1. Get the The RadioHead library from [http://www.airspayce.com/mikem/arduino/RadioHead/](http://www.airspayce.com/mikem/arduino/RadioHead/)works for communication between two devices, a server and a client. There is a If you want to install the RadioHead library, click on the link with the ending _.zip_ that on the previously mentioned website.</br>Then, add the library to your Arduino IDE. Once added, you can click open the example file under examples --> radiohead --> rf95 --> client or server</br> In the (example) sketch, make sure to assign LED to something other than 9. If set to download9, the restart of the LoRa board will be triggered.

2## LoRa WAN[[File:LoRaWANSystemDiagram. Add JPG|750px]] LoRa WAN is the library to your Arduino IDEinternet-based version of LoRa. One added you While LoRa communication only works between generally two devices, LoRa WAN can open communicate between hundreds of devices by the example file under examples means of a gateway. LoRa WAN consists of end-nodes and at least one gateway. Communication between the gateway and the nodes is bidirectional and based on LoRa radio communication.  __List of tutorial videos on some useful related LoRa WAN subjects__ [LGo1-N configuration](https://www.youtube.com/watch?v=BqUpkWl_EsQ)</br>[LoRa Wan tutorial](https://www.youtube.com/watch?v=VldgrTKdAqo)</br>[LG01-N gateway setup](https://www.youtube.com/watch?v=VJEOu2AATXU)</br></br> [Different device types - Class A,B,C - Youtube tutorial](https://www.youtube.com/watch?v=ShJ5RERof5I)</br>[Fresnel zone](https://www.youtube.com/watch?v=HWOivbJjw7s)</br>[EIRP and ERP](https://www.youtube.com/watch?v=LEucMthGJtc)</br>[RSSI and SNR](https://www.youtube.com/watch?v=RpTw1fGhI68)</br>[LoRa Packet Format, Time on Air and Adaptive Data Rate](https://www.youtube.com/watch?v=C_Rh5GSENA4)</br>[Different types of LoRa chips](https://www.youtube.com/watch?v=0FaFVD5fedc&list=PLmL13yqb6OxdeOi97EvI8QeO8o-PqeQ0g&index=18)</br>[LoRa End Node Libraries](https://www.youtube.com/watch?v=0dnnqToK28A&list=PLmL13yqb6OxdeOi97EvI8QeO8o-PqeQ0g&index=20) ## Gateway A gateway can be a [LG01-N Single Channel Gateway](https://www.seeedstudio.com/LG01-N-Single-Channel-LoRa-IoT-Gateway-p-2935.html). It works in a LoRaWAN setup and communicates with the nodes. In a LoRaWAN setup, the nodes don't communicate with each other. A gateway creates a connection with the internet and uploads the data to a platform such as TheThingsNetwork (TTN). This is a potential great opportunity for improving the current system at the farm.</br> radiohead[[File:DraginoLG01-N. JPG|250px]]

Protocol buffers are a data serialization format from Google which are supported in multiple programming languages. Protocol Buffers messages are encoded in a binary format, which means they are not human-readable unless we decode them back to a readable format. One of the main advantages of using Protocol Buffers is that the serialization and deserialization process is fast and the generated messages are small.[^protob] _Nanopb_ is a version of the protocol buffer in the programming language C, which works well with 32 bit systems such as the Arduino.  This [_dfrobot_ tutorial](https://www.dfrobot.com/blog-1161.html) leads you through installing the Nanopb library and compiler on your laptop. _Nanopb_ is a version of the protocol buffer in the programming language C, which works well with 32 bit systems such as the Arduino. You can use [this online proto buffer decoder](https://protogen.marcgravell.com/decode) to decode proto buffer messages that were encoded for sending.  The Nanopb library needs a `.proto` file that clarifies the variables that will be serialized. Once, the different types of variables are serialized or encoded, they are unreadable for humans in a binary format. This number is expressed as hexadecimal that can easily be sent over wireless radio as it requires small amounts of data.

Protocol buffers are a data serialization format from Google which are supported in multiple programming languages. Protocol Buffers messages are The encoded in a binary format, which means they are not human-readable unless we decode them back message needs to a readable formatbe decoded on the side of the receiver. One of The receiver also needs to know the main advantages of using Protocol Buffers is that specific variable types in the serialization and deserialization process is fast and message to properly decode the generated messages are smallmessage.The [^protobabovementioned tutorial] The (https://www.dfrobot.com/blog-1161.html) only walks you through setting up the Nanopb library needs environemnt on your laptio and encoding a 'message.proto' file that clarifies the variables that will be serializedA [different tutorial by _dfrobot_ shows how to encode and decode messages between an Arduino and ESP32](http://dfrobot.blogspot.com/2019/02/esp32-arduino-tutorial-25-3-protocol. Once, the different types of variables are serialized, they are unreadable for humans in a binary formathtml).