LoRaWAN™ is the most widely deployed LPWAN technology across the world as on this day. Although it is facing stiff competition from some rival LPWAN standards, it is definitely going to stay for some time. With many telcos around the world committing to its deployment and a strong backing of companies for the LoRaWAN™ Alliance, it will be interesting to see how far it goes.
We at Radiostudio have recently taken up the challenge to explore this exciting technology. As always, our approach is to conceptualize possible applications that can be built with a new technology. In the process, we stumbled upon the Microchip RN2483 LoRa chip and did a few exciting trials. In this blog post, we present to you a very brief introduction to LoRa technology along with a short feature overview of the Microchip RN 2483 Lora transceiver chip.
What is LoRa & LoRaWan?
Overview
LoRaWAN™ is a Low Power Wide Area Network (LPWAN) specification intended for wireless, battery operated devices within a regional, national or global network. It has been developed as a wireless, physical layer, radio communication protocol called LoRa (Long Range). As the name implies, it is designed for a fairly long communication range of up to 15 km in rural and suburban areas and about 5kms in urban areas and it has the advantage of being extremely energy efficient. Of course, the downside is that it has a very limited data rate of about 50 kbps maximum. But for a sensor or machine communication, this data rate is enough and so that’s where lies the biggest potential of LoRa.
LoRa Applications
LoRaWAN targets key applications of Internet of Things mostly centered around monitoring sensor data and management of sensor networks. The LoRaWAN specification provides seamless interoperability among smart things without the need of complex local installations and leverages the open ISM band for radio communication. This gives a lot of freedom to the network implementors, enabling the rollout of “Internet of Things” based applications around a wider geographical region.
LoRa’s range gives it an advantage over the other LAN and PAN technologies which cannot be deployed over a large span of geography. That’s why LoRa has immense potential for use cases such as
- Smart Farming / Agriculture
- Home Automation
- Industrial Automation
- Smart Garbage Bins
- Smart Grid
- Smart Lighting
- Smart Water Metering
Check out this LoRa application catalog by Semtech, the company that is leading the LoRa development and standardization.
LoRaWan Device Classification
LoRaWAN has three different classes of end-point devices to address the different communication needs reflected in the wide range of applications:
- Bi-directional end-devices (Class A): Class A operation allows bi-directional communications whereby each end-device’s uplink transmission is followed by two short downlink receive windows. Thus Class A operation is suited for applications that require a very limited downlink as the downlink transmission can happen only after the end-device has sent an uplink transmission. Downlink communications from the server at any other time will have to wait until the next scheduled uplink.
- Bi-directional end-devices with scheduled receive slots (Class B): In addition to the Class A random receive windows, Class B devices open extra receive windows at scheduled times. In order for the End-device to open its receive window at the scheduled time, it receives a time synchronized Beacon from the gateway. This allows the server to know when the end-device is listening.
- Bi-directional end-devices with maximal receive slots (Class C): Class C operation supports nearly continuously open receive windows, only closed when transmitting. Thus Class C end-devices consume maximum power and are more suited for near real-time applications.
Microchip RN2483 LoRa Module
Microchip offers two LoRa transceiver modules, RN2483 with 433 MHz & 868 Mhz and RN2903 with 915 MHz. Both operate on the Class A protocol. These modules are easy to integrate with an MCU or a PC and can be programmed through the standard UART interface.
Features
- On-board LoRaWAN™ Class A protocol stack
- ASCII command interface over UART
- Compact form factor 17.8 x 26.7 x 3 mm
- Castellated SMT pads for easy and reliable PCB mounting
- Device Firmware Upgrade (DFU) over UART
- 14 GPIO for control, status, and ADC
- Tx Power of upto +14 dBm. (+20 dBm supported for RN2903)
- Highly integrated module with MCU, crystal, EUI-64 Node Identity Serial EEPROM, Radio transceiver with analog front end, and matching circuitry
- Environmentally friendly, RoHS compliant
- European R&TTE Directive Assessed Radio Module
Reference Links
Buckle Up for your LoRa Experience
Over the last few months, we have done some extensive tests with RN2483 and I will be presenting a chronicle of my experiences in the subsequent posts. For now, I want to leave you with something that can expedite your hardware development if you are thinking of exploring LoRa with the Microchip solution.
I am giving away the PCB design file for the Microchip RN2483 breakout module that I designed for my hardware.
Microchip also offers an evaluation kit consisting of a LoRa gateway module (868 Mhz) that can be used to setup your private LoRa network for testing. But before you try it out, please ensure that you adhere to the regulatory constraints for wireless transmission on ISM band, as per your country’s laws.
It is exciting to be part of the LPWAN revolution and I hope that by the end of 2017, there will be more player in the arena. We are working closely with a few partners to explore some unique solutions around it, and so I am keenly following this development. Rest assured I will be sharing my experiences.
You can drop a comment below to share and express your thoughts on LoRa or on LPWAN in general. In case you have a problem statement that can be addressed with LoRa then please get in touch or you can book an appointment with us to discuss your requirements.
