LoRa and LoRaWAN
LoRa® and LoRaWAN™ belong to the category of non-cellular LPWAN wireless communication network protocols and layers, operating in the license-free spectrum.
LoRa defines the physical layer, the reason behind the long-range communication. It refers to a wireless modulation format allowing a low-power, high radio budget communication. LoRa is a patented technology developed by Cycleo of Grenoble, France, and acquired by Semtech of California in 2012. LoRa modulation can be used in networks without LoRaWAN.
LoRa devices transmit in an open frequency range (915 MHz in North America) which do not require a government license to transmit on.
LoRaWAN defines the communication protocol and system architecture for the network. It refers to a network protocol using LoRa chips for the communication. Technically one can create a LoRaWAN network without LoRa radio, but it wouldn’t be practical. The two are related but distinct.
LoRaWAN is the most adopted type of LPWAN, and promises ubiquitous connectivity in outdoor IoT applications, while keeping network structures, and management, simple.
The LoRa Alliance®, a non-profit association and the fastest growing technology alliance, drives the standardization and global harmonization of the LoRaWAN protocol.
LoRaWAN™ defines the communication protocol and system architecture for the network, while the LoRa® physical layer enables the long-range communication link. LoRaWAN communication protocol ensures reliable communication, secure communication and adds additional headers to the data packets.
LoRaWAN™ is designed from the bottom up to optimize LPWANs for battery lifetime, capacity, range, and cost.
LoRaWAN networks use the LoRa spread spectrum modulation technique derived from chirp spread spectrum (CSS) technology. LoRa technology is a long range, low power wireless platform that has become the de facto technology for Internet of Things (IoT) networks worldwide.
The advantage of LoRaWAN is in the technology’s long range capability. A single gateway or base station can cover entire cities or hundreds of square kilometres. Range highly depends on the environment or obstructions in a given location, but LoRa® and LoRaWAN have a link budget greater than any other standardized communication technology. The link budget, typically given in decibels (dB), is the primary factor in determining the range in a given environment. With a minimal amount of infrastructure, entire provinces can easily be covered.
How It Works
In a LoRaWAN™ network, nodes are not associated with a specific gateway. Instead, data transmitted by a node is typically received by multiple gateways. Each gateway will forward the received packet from the end-node to the cloud-based network server via some backhaul (such as cellular, Ethernet, satellite, or Wi-Fi). The intelligence and complexity is pushed to the network server, which manages the network and will filter redundant received packets, perform security checks, and schedule acknowledgments through the optimal gateway.
If a node is mobile or moving there is no handover needed from gateway to gateway, which is a critical feature to enable asset tracking applications–a major target application vertical for IoT. Note that unlike cellular LPWAN networks, any mobile application requires LoRaWAN infrastructure within range of your mobile assets.
The LoRaWAN™ protocol is actively supported by the LoRa Alliance®, an open and non-profit association of members. It is the fastest growing tech ecosystem in the technology world, with over 500 members, including mobile network operators, base station suppliers, sensor manufacturers, and system integrators.
The nodes in a LoRaWAN network are asynchronous and communicate when they have data ready to send, whether event-driven or scheduled. This type of protocol is typically referred to as the “Aloha method”.
This is contrasted with mesh or synchronous networks, such as cellular, where the nodes frequently have to “wake up” to synchronize with the network and check for messages. This synchronization consumes significant energy and is the number one driver of battery lifetime reduction.
In a recent study and comparison done by GSMA of the various technologies addressing the LPWAN space, LoRaWAN showed a 300% to 500% advantage compared to all other technology options.
We are a Cisco Select Partner, and as of Fall 2019, one of only two Canadian companies to have achieved this select certification.
High network capacity in a LoRaWAN™ network is achieved by utilizing an adaptive data rate and by using a multichannel multi-modem transceiver in the gateway so that simultaneous messages on multiple channels can be received. The critical factors effecting capacity are the number of concurrent channels, data rate (time on air), the payload length, and how often nodes transmit.
Since LoRa® is a spread spectrum-based modulation, the signals are practically orthogonal to each other when different spreading factors are utilized. As the spreading factor changes, the effective data rate also changes. The gateway takes advantage of this property by being able to receive multiple different data rates on the same channel at the same time. If a node has a good link and is close to a gateway, there is no reason for it to always use the lowest data rate and fill up the available spectrum longer than it needs to. By shifting the data rate higher, the time on air is shortened—opening up more potential space for other nodes to transmit.
Adaptive data rate also optimizes the battery lifetime of a node. In order to make adaptive data rate work, symmetrical uplink and downlink is required with sufficient capacity.
These features enable a LoRaWAN network to have a very high capacity and make the network scalable. A network can be deployed with a minimal amount of infrastructure, and as capacity is needed, more gateways can be added, shifting up the data rates, reducing the amount of overhearing to other gateways, and scaling the capacity by 6-8x. Other LPWAN alternatives do not have the scalability of LoRaWAN due to technology trade-offs, which limit downlink capacity or make the downlink range asymmetrical to the uplink range.
What is the ROI of implementing a LoRaWAN network? We’ll help you figure it out.