What is LoRa?
LoRa technology is a sort of new wireless protocol designed precisely for long-range connectivity and low-power communications. LoRa stands for Long Range Radio and it is mainly targeted for the Internet of Things (IoT) and M2M networks. This technology will allow multi-tenant or public networks to connect a number of applications running on the same network.
LoRa Alliance was designed to normalize LPWAN (Low Power Wide Area Networks) for IoT. A LoRa Technology and the open Lora WAN protocol enable smart IoT applications that solve some of the biggest challenges facing our planet: natural resource reduction, pollution control, disaster prevention, energy management, infrastructure efficiency, and more.
Each individual LoRa gateway has the capability to handle up to millions of nodes. The signals can extend a significant distance, which means that there is less structure required, making constructing a network faster and much cheaper to implement.
LoRa also features an adaptive data rate algorithm to help make the best use of the nodes network capacity and battery life. The LoRa protocol includes a number of different layers including application and device-level for secure communications, encryption at the network.
LoRa network architecture
A LoRa network contains several elements:
The endpoints are the elements of the LoRa network where the control or sensing is undertaken. They are normally remotely located.
The gateway receives the infrastructures from the LoRa endpoints and then transfers them onto the backhaul system. This part of the LoRa network can be cellular, Ethernet or any other telecommunications link wireless or wired. The gateways are connected to the network server using typical IP connections. In this way the data uses a typical protocol but can be connected to any telecommunications network, whether private or public. In view of the likeness of a LoRa network to that of a cellular one, LoRaWAN gateways may often be co-located with a cellular base station. In this way, they are able to use extra capacity on the backhaul network.
LoRa Network Server
The LoRa network server succeeds in the network and as part of its function, it acts to remove duplicate packets, adapts data rates and schedules acknowledgment. In the assessment of the way in which it can be deployed and connected, makes it very easy to deploy a LoRa network.
Then, a remote computer can control the actions of the endpoints or collect data from the endpoints – the LoRa network being almost translucent.
In terms of the authentic architecture for the LoRa network, the nodes are typically in a star-of-stars topology with gateways forming a see-through bridge. These relay messages between the central network server and end-devices in the backend.
Communication to end point nodes is usually bi-directional, but it is also possible to support multicast operation, and this is useful for features such as the like or other mass distribution messages or software upgrades.
LoRa Technology basics
There are several key elements of LoRa technology. Some of its key features include the following:
- Up to Millions of nodes
- Long battery life; in spare of ten years
- Long range; 15-20 km.
There are various elements to LoRa technology that provide the overall connectivity and functionality.
LoRa protocol stack: LoRa Alliance has also defined an open protocol stack. The creation of this open-source stack has allowed the concept of LoRa to raise because of all the different types of companies involved in LoRa development, deployment and use have been able to come together to create a low cost and easy to use solution for connectivity to all manners of connected IoT devices.
LoRa network design: (LoRaWAN): Besides the RF elements of the LoRa wireless system, there are some other elements of the network architecture, including the presence of overall system architecture, Server, backhaul and the application computers. The overall architecture is often mentioned as LoRaWAN.
LoRa PHY / RF interface: The LoRa physical layer or PHY is key to the operation of the system. It governs the aspects of the RF signal that is transmitted between the nodes or endpoints, i.e. LoRa gateway and the sensors are where signals are received. The physical layer or radio interface governs aspects of the signal including the modulation format, power levels, frequencies, signaling between the transmitting and receiving elements, and other related topics.
Features of LoRa Protocol
The following table displays some of the key features of the LoRa protocol such as modulation, capacity and range.
|Range||2-5Km Urban (1.24-3.1 mi),|
15Km suburban (9.3 mi)
|Frequency||ISM 868/915 MHz|
|Modulation||Spread-spectrum modulation type based on FM pulses which differ.|
|Capacity||One LoRa gateway takes thousands of nodes|
|Battery||Long battery life|
|LoRa Physical layer||Frequency, power, modulation and signaling between nodes and gateways|
LoRa network security
The issue of network security is becoming gradually important. As such LoRa networks require high levels of security to prevent the trouble of any systems.
To attain the required levels of security for LoRa networks, several layers of encryption have been used:
- Device specific key (EUI128).
- The Unique Network key (EUI64) guarantees security on the network level.
- Unique Application key (EUI64) certify end to end security.
Using these layers of encryption ensures that the LoRa network remains suitably secure.
LoRa wireless technology is preferably placed to be used in a variety of applications.
The long-range and low power capabilities mean that end points can be deployed in a wide variety of places, outside and inside buildings and still have the ability to be able to communicate with the gateway.
As the system is easy to deploy and it can be used for a large number of IoT, Internet Things, and machine to machine, applications, M2M.
Applications for LoRa wireless technology include inventory tracking, smart metering, vending machine data and monitoring; utility applications; automotive industry, etc. In fact, anywhere where control and data reporting may be needed.
LoRa technology is mainly attractive for many applications because of its long-range capability. Coverage is easy to provide and New nodes can easily be connected and activated.
Picocells & Gateways: Sensors capture then transmit data to gateways over distances that are close and far, outdoor and indoor, with the lowest power requirement
Transceivers & End-Nodes: Transceivers configured with LoRa Technology are fixed into sensor devices or end-nodes, designed for an assembly of industry applications.
LoRa Technology is the wireless modulation or physical (PHY) silicon layer, used to create the long-range communication link.
LoRa physical layer uses a form of spread spectrum modulation. The LoRa modulation system uses wide-band linear frequency-controlled pulses. The level of frequency increase or decrease over time is used to encode the data to be transmitted, such as; a form of chirp modulation.
This type of modulation enables LoRa wireless systems to demodulate signals that are 20dB below the noise floor when the demodulation is combined with forwarding error correction, FEC. When compared to a traditional FSK system; the link budget for a LoRa system can deliver an improvement of more than 25dB.
As a result of the point that the transmission is spread in a pseudo-random fashion, it may be difficult for non-Lora users to detect and appears like noise. This can support in the security of the system.
A further advantage of the system is that the chirp modulation and the system, in general, is tolerant of frequency offsets and as a result, it is possible to use a basic crystal oscillator with a 20-30 ppm acceptance rather than a temperature paying oscillator, TCXO. This can provide some good cost savings within the node electronic circuitry.
Meanwhile, LoRa describes the lower physical layer, the upper networking layers were absent. LoRaWAN is one of the numerous protocols that were developed to describe the upper layers of the network. LoRaWAN is a cloud-based media access control (MAC) layer protocol but acts mainly as a network layer protocol to manage communication between end-node devices and LPWAN gateways, as steering protocol, maintained by the LoRa Alliance. LoRaWAN specification version 1.0 was released on June 2015.
LoRaWAN defines the system architecture and communication protocol for the network, while the LoRa physical layer allows the long-range communication link. LoRaWAN is also responsible for managing the data rate, power for all devices and communication frequencies. Devices in the network transmit whenever they have data available to send. Data transmitted by an end-node device is received by multiple gateways, which forward the data packets to a central network server. The server filters duplicate the packets, performs security checks, and manages the network. Data is then furthered to application servers. The technology shows high consistency for the modest load; however, it has some performance problems related to sending acknowledgments
As with many other systems, an industry body was set up to develop then promote the LoRa wireless system across the industry called the LoRa Alliance. It was launched in March 2015. As the Alliance states, it was set up to provide an open global standard for secure, carrier-grade IoT LPWAN connectivity.
Although LoRa had been essentially developed by Semtech, opening he standard out enabled it to be adopted by a wide number of companies, thereby growing the ecosystem and gaining significantly greater engagement, a wider variety of products and an overall increase in usage and acceptance.
The founding members of the LoRa Alliance include Actility, Cisco, Eolane, IBM, Kerlink, IMST, MultiTech, Sagemcom, Semtech, and Microchip Technology, as well as lead telecom operators: Bouygues Telecom, KPN, SingTel, Proximus, Swisscom, and FastNet (part of Telkom South Africa).