LoRa communication within STM32

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What are the most important information to know about LoRa communication?
What are the resources offered by ST and dedicated to the development of LoRa solutions?

This FAQ concerns the LoRa communication, this tutorial contains the basic information to know about LoRa Technology and several helpful links to get started with, based on STM32 products.
 

1. What is LoRa?  

LoRa is a wireless communication technology, it is developed to create low-power, wide-area networks (LPWANs) required for machine-to-machine and IoT applications connecting many devices.  
 

2. What are the LoRa characteristics? How far can LoRa transmit? 

LoRa is a long-range transmission technology for higher than 10 Km and characterized by its low power consumption and its: 

• Long range: >15 km / 9 mi range 
• Low power: 5-10 year expected battery lifetime. 
• Low-cost: from end-node sensor cost to upfront infrastructure investment 
• Secure: with embedded end-to-end AES-128 encryption of data 
• Geolocation: enables indoor/outdoor tracking without GPS 

Note:

It is important to highlight that the range LoRa transmits for is affected by multiple factors which are mainly the network used, the node-gateway positioning, the antenna, the environment…

3. What is LoRaWAN protocol (Long Range Wide Area Network)?

LoRaWAN is a global Low Power Wide Area Network (LPWAN) specification providing bi-directional communications which allows connection of LoRa devices to the internet. 
LoRaWAN differs from LoRa by the inclusion of a physical layer. It consists of several elements:

• End devices (nodes): the elements where the sensing or control is undertaken. Communication to end devices is generally bi-directional, but it is also possible to support multicast operation, and this is useful for features such as software upgrades or other mass distribution messages.
• Gateway: receives the communications from the LoRaWAN end devices and then transfers them onto the backhaul system. They are connected to the network server using standard IP connections. 
• Network Server: The LoRaWAN network server manages the network. The network server acts to eliminate duplicate packets, schedules acknowledgement, and adapts data rates.
• Application Server: a remote device running the application and controlling the actions of the end devices or collecting data from them.

3.1 LoRa Modulation

Regarding the LoRa modulation characteristics, they are defined for each region and specified in the LoRaWAN Regional Parameters document, from the LoRa Alliance.

3.2 Is remote control via LoRa allowed?

LoRa is a Sub-GHz wireless technology enabling low data rate communication over long distances so, yes, it is possible we can send data via lora protocol to another device and control it remotely.
 

3.3 Shortening the LoRa send time

In order to maximize the range, it is possible to:

• increase the link budget by decreasing the bandwidth to the last possible value but be careful this alternative might affect the communication quality.
• make the spreading factor much higher.
• improve the used antenna.

3.4 Advantages of deploying a LoRaWAN network

Deploying the LoRaWAN network has several advantages presented below: 

4. Useful links

• LoRaWAN training: ST Online training LoRaWAN
• LoRaWAN stack training: STM32WL Online training LoRaWAN stack
• LPWAN workshop MOOC: Training on how to connect your application to the cloud via a long-range network.
• STM32 LoRa: ST web page gathering all relevant information about LoRa connectivity.
• LPWAN Workshop: MOOC training
• How to build a LoRa® application with STM32CubeWL
• STM32 LoRaWAN® Expansion Package for STM32Cube
• STMicroelectronics provide a range of products; you will find them in the LoRaWAN Products page.
  STM32WL microcontrollers meet the requirements of a wide range of Low-Power Wide Area Network (LPWAN) wireless applications in industrial and consumer Internet-of-Things (IoT); LoRaWAN stacks is available in STM32CubeWL, complying with the physical layer requirements of the LoRaWAN® specification released by the LoRa Alliance.
• IoT connectivity made easier STM32 MCUs & LoRa