Understanding the Basics of Migrating an IoT Sensor Design to LoRaWAN
22 June 2018 / by Patrick van Eijk
Semtech’s LoRa® devices and wireless radio (RF) frequency technology (LoRa Technology) is quickly becoming the de facto Internet of Things (IoT) technology.
The implementation of LoRa Technology into millions of sensors deployed around the globe and the ability to utilize LoRa-enabled devices in various applications continues to drive its adoption. The LoRaWAN® open standard, offered by the LoRa Alliance®, enables these long range, low power sensors to connect to gateways throughout the world. Semtech’s new white paper, “Migrating an Internet of Things (IoT) Sensor Design to LoRaWAN”, explains the relationship between LoRa Technology and the LoRaWAN standard and how to connect sensors to a LoRaWAN network. Below, read key points from the newly released white paper.
What is LoRa?
LoRa (short for long range) is a spread spectrum modulation technique derived from existing Chirp Spread Spectrum (CSS) technology. It offers a trade-off of sensitivity versus data rate and bandwidth. It uses orthogonal spreading factors which allow the network to make adaptive optimizations of an individual end-node’s power levels and data rates with a goal of preserving end-node battery life. (Read more on page 2 of the white paper).
What is LoRaWAN?
The LoRaWAN open standard is a low power wide area network (LPWAN) protocol specifically designed for long range, low power sensor applications. This LoRaWAN standard provides the ability to create a high capacity star network, and not just individual point-to-point LoRa links between two devices. There are different kinds of networks: 1) a real network where end-nodes or IoT devices can be connected by sending an over the air activation (OOTA) request to one or more LoRaWAN gateways, and 2) a network where there is a central entity in the Cloud that manages the network and optimizes individual end-node battery life by making trade-offs between end-node transmit power and spreading factors, etc. Finally, the standard offers a network where the end-node’s data is routed to the correct application server in the Cloud. (Read more on page 5 of the white paper).
How to Convert Hardware Design to LoRaWAN
The key objective of any IoT device is to get relatively small amounts of data to a Cloud-based application. If you are interested in migrating your existing IoT device or end-node to LoRaWAN, you will have to first carefully analyze your message payload requirements as well as the periodicity of these messages. If you are able to fit your sensor or other end-node data into an 11-byte payload (or multiple 11-byte payloads) with an average radio message between minutes, hours or days (assuming a battery operated device), converting your existing device to LoRaWAN is possible. (Read more on page 12 of the white paper).
How to Convert Software Design to LoRaWAN
The scope of the software development will depend on the implementation of the hardware architecture of the LoRaWAN end node. Typically, the software development in a LoRaWAN-based device conversion will involve replacing the current communication protocol stack (it could be BLE, ZigBee, Z-Wave, etc.) with a LoRaWAN protocol stack. (Read more on page 15 of the white paper).
Ready to start converting your sensors? Download the white paper!
Semtech, the Semtech logo, LoRa and LoRaWAN are registered trademarks or service marks of Semtech Corporation or its affiliates.