LoRa: Long Range Connectivity Explained

What Is LoRa? 

LoRa (short for Long Range) is a spread spectrum technique for modulation derived from the chirp spread spectrum (CSS) technology.  It is a long-range, low-power wireless communication platform essential to the Internet of Things (IoT).  LoRa devices and networks enable smart IoT applications, solving some of our biggest challenges:  natural resource reduction, pollution control, energy management, infrastructure efficiency, and disaster prevention.  LoRa wireless technology permits inexpensive, long range connectivity for mobile communication among IoT devices in rural, remote, and offshore industries.  It is commonly used in mining, natural resource management, transcontinental logistics, supply chain management, and renewable energy projects.  

How Long is Long-Range 

Using LoRa wireless technology, sensors have been verified as lasting for years on a single button cell battery and, under ideal conditions, reach ranges of 10 miles in rural areas and 3 miles in the city.  

Benefits of LoRa 

One of the primary benefits of LoRa is that for the same power costs, its transmission distance will exceed other series of wireless modules.  LoRa solved the long-standing problem of maintaining low power consumption while also maintaining long-distance transmission.  

LoRa Modulation Mode has anti-interference solid technology.  It has outstanding spread spectrum modulation and forward error correction.  It can even distinguish the extra data from noise.  Its strong anti-interference makes for more stable and reliable transmitted data.  

Finally, the LoRa modulation tech performs a unique spread function on the signal.  Under the same data rate conditions, its modulation method can obtain 8 to 10 dBm higher than transfer modulation methods.  The longer the transmission distance and communication range, the weaker the signal.  The higher sensitivity of LoRa allows the weaker signal to be received over a long transmission distance.

Drawbacks of LoRa

LoRa transmits as far as it does by sacrificing its data transmission rate.  The higher the transmission rate, the closer the distance. If a project has high transmission rate requirements, the LoRa module is not a good choice. LoRa is also more expensive than other modules. Unless funds are particularly tight, many IT designers will still recommend LoRa because of its performance.

Use Cases of LoRa

LoRa devices have transformed the I0T by enabling data communication over a long range at a very low power cost.  LoRa has become the go-to technology for the IoT based on its widespread use.  It will likely connect the next billion or so IoT devices.  

LoRa technology can be used in rural or indoor use cases in smart agriculture, smart cities, industrial IoT (IIoT), smart homes and buildings, smart utilities and meters, smart cities, and smart supply chain and logistics management. It is also ideal for water and gas metering and asset tracking.  

An interesting use case example is a hybrid IoT/BMS for on-premises energy management and control.  They can integrate legacy systems with new systems by creating a network with LoRa and LoRaWAN.  Data points feed into a legacy BMS which uses the data to manage the building more efficiently.  

Alternatives of LoRa 

Common cellular alternatives to a LoRaWAN include Long Term Evolution for Machine (LTE-M) and Narrow Band IoT NB-IoT.  LTE-M is a low-power wide area network technology developed to enable a wide range of cellular devices and services. SigFoxd uses a slow modulation race to achieve a more extended range.  It's excellent for applications where the need is to send small, infrequent data bursts.  

Most Popular Suppliers of LoRa Hardware 

RAK Wireless is a crucial supplier of LoRa and other Internet of Things products.  It seeks to accelerate time to market for underserved and emerging markets.  

Actility, a French company, is an expert in IoT connectivity management platforms.  

Rothamsted Research, a UK company, providing science in agriculture since 1843.  

How to create a LoRa product 

The best way to develop and sell your own LaRa end devices is to follow these steps.  

  • Prototype -  Select a LoRa module and development kit, a popular one being Grove, suitable for environmental monitoring.  Add more functions by adding new modules and sensors.  Each part is designed with a particular mindset, so it comes down to plug-and-play for our end proof of concept.  
  • Golden Sample - Once you have proof of concept, its time to make a golden sample to be used as a blueprint for mass production of a product.  You'll need to consider
  • Hardware Design
  • Embedded Software Design
  • Mechanical Enclosure Design
  • Packaging Design
  • Certification
  • Distribution - Decide where and how you will distribute it.  Develop a plan or network for distribution.  

Considerations when creating a LoRa Product 

When creating a LoRa product, there are several things to consider.

Selection of Architecture

You choose between your own design and a module or modem-based architecture based on:

  • Maturity of device specs:  feasibility test, market test, or mass production
  • Electronic and RF development skills available to the team
  • Budget
  • Timeline - specs, schematics, software development, test bench development
  • How many will you sell and at what price
  • Development resources available
  • ISM band - band, where the device will be deployed, is based on the impact of the architecture due to antenna matching and tuning to the frequency band.

Antenna Design

The antenna is critical in any communicating device, especially where sensitivity is a major issue.  There are three typical antenna designs:

  • Dedicated OEM antenna tuned for LoRa frequency is the easiest choice as it is a perfect fit for LoRa.  Also, however, the most expensive.
  • PCB-Antenna, a simple trace on the circuit, However, things like copy width and thickness must be considered during design.
  • Simple quarter-wave wire antennas can be the easiest to implement.  It isn't easy to ensure repeatability in a product and deliver consistent length. Quarter wave design must also have correct mechanical parts to maintain the wire properly inside the product to ensure consistent RF performance.

Device Autonomy  

Before developing hardware and software, you must take device autonomy requirements into account because both will heavily impact power consumption.  For hardware, consider:

  • Choice of the Multipoint Control Unit - MCU allows a multipoint audio/video conference to be controlled and moderated from one single location.
  • Choice of the battery and its power management
  • Hardware issues (pull-up and pull-down resistors, pins not connected, mA leak inside components)
  • Sleeping mode of peripherals - the power-saving state the product will enter when it is not in use

For ultimate battery life, five consumption modes must be identified:

  • Sleeping: the mode when everything in the product is sleeping or off
  • Idle: everything is sleeping except the Multipoint Control Unit
  • Running: the device is awake and fully running its functionalities
  • LoRa Tx: the device is awake and sending data
  • LoRa Rx: the device is awake and listening or receiving data

You then calculate how much time the device will spend in each mode to calculate power consumption per hour.  Most developers recommend using the worst care figures for all of the modes.  

Integration and Development

The starting entry point for a device maker is a starter kit that comprises a development board with connectors for sensors or other peripherals and the LoRa radio board. The key idea of a starter kit is to add LoRa connectivity to a development kit quickly. The LoRaWAN protocol stack is ready in the starter kit and offers a simple API to send a message.

Software Development

The software development phase depends on the hardware architecture you choose for your device. The most straightforward case is the LoRa modem architecture: the whole LoRaWAN stack is already implemented inside the modem, and the communication is managed by itself. The developer only needs to implement the initialization of the stack to be able to easily send or receive messages.

The module manufacturer may provide a read-to-use LoRaWAN stack implementation fitting the integrated module MCU with module architectures. In that case, the developer must initialize and manage the API with commands for the LoRaWAN stack.

You must have a test mode inside the app.  It is necessary and helpful for various reasons:

  • Tests during development
  • Interoperability with network service
  • LoRaWAN certification (LoRa Alliance provides)
  • End-of-Line manufacturing test

Test mode can be activated through a command on a dedicated FPort.  The test mode can then check all available MAC commands and communicate with the service to check all message types and integrity.  

Or click here to learn more ->