LoRa

Last updated
LoRa
LoRa Module with antenna and SPI wires attached.jpg
A LoRa module
Developed by Cycleo, Semtech
Connector typeSPI/I2C
Compatible hardwareSX1261, SX1262, SX1268, SX1272, SX1276, SX1278
Physical range>10 kilometres (6.2 mi) in perfect conditions

LoRa (from "long range") is a physical proprietary radio communication technique. [1] It is based on spread spectrum modulation techniques derived from chirp spread spectrum (CSS) technology. [2] It was developed by Cycleo, a company of Grenoble, France, and patented in 2014. [3] Cycleo was later acquired by Semtech. [4]

Contents

LoRaWAN (wide area network) defines the communication protocol and system architecture. LoRaWAN is an official standard of the International Telecommunication Union (ITU), ITU-T Y.4480. [5] The continued development of the LoRaWAN protocol is managed by the open, non-profit LoRa Alliance, of which Semtech is a founding member.

Together, LoRa and LoRaWAN define a low-power, wide-area (LPWA) networking protocol designed to wirelessly connect battery operated devices to the Internet in regional, national or global networks, and targets key Internet of things (IoT) requirements, such as bi-directional communication, end-to-end security, mobility and localization services. The low power, low bit rate, and IoT use distinguish this type of network from a wireless WAN that is designed to connect users or businesses, and carry more data, using more power. The LoRaWAN data rate ranges from 0.3 kbit/s to 50 kbit/s per channel. [6]

Features

LoRa uses license-free sub-gigahertz radio frequency bands EU868 (863–870/873 MHz) in Europe; AU915/AS923-1 (915–928 MHz) in South America; US915 (902–928 MHz) in North America; IN865 (865–867 MHz) in India; and AS923 (915–928 MHz) in Asia; [7] LoRa enables long-range transmissions with low power consumption. [8] The technology covers the physical layer, while other technologies and protocols such as LoRaWAN (long range wide area network) cover the upper layers. It can achieve data rates between 0.3 kbit/s and 27 kbit/s, depending upon the spreading factor. [9]

LoRa is one of the most popular low-power wireless sensor network technologies for the implementation of the Internet of Things, offering long-range communication compared to technologies such as Zigbee or Bluetooth, but with lower data rates. [10]

LoRa devices have geolocation capabilities used for trilaterating positions of devices via timestamps from gateways. [11]

LoRa PHY

LoRa uses a proprietary spread spectrum modulation that is similar to and a derivative of chirp spread spectrum (CSS) modulation. Each symbol is represented by a cyclic shifted chirp over the frequency interval () where is the center frequency and the bandwidth of the signal (in Hertz). The spreading factor (SF) is a selectable radio parameter from 5 to 12 [12] and represents the number of bits sent per symbol and in addition determines how much the information is spread over time. [2] There are different initial frequencies of the cyclic shifted chirp (the instantaneous frequency is linearly increased and wrapped to when it reaches the maximum frequency ). [13] The symbol rate is determined by . LoRa can trade off data rate for sensitivity (assuming a fixed channel bandwidth ) by selecting the SF, i.e. the amount of spread used. A lower SF corresponds to a higher data rate but a worse sensitivity, a higher SF implies a better sensitivity but a lower data rate. [14] Compared to lower SF, sending the same amount of data with higher SF needs more transmission time, known as time-on-air. More time-on-air means that the modem is transmitting for a longer time and consuming more energy. Typical LoRa modems support transmit powers up to +22 dBm. [12] However, the regulations of the respective country may additionally limit the allowed transmit power. Higher transmit power results in higher signal power at the receiver and hence a higher link budget, but at the cost of consuming more energy. There are measurement studies of LoRa performance with regard to energy consumption, communication distances, and medium access efficiency. [15] According to the LoRa Development Portal, the range provided by LoRa can be up to 3 miles (4.8 km) in urban areas, and up to 10 miles (16 km) or more in rural areas (line of sight). [16]

In addition, LoRa uses forward error correction coding to improve resilience against interference. LoRa's high range is characterized by high wireless link budgets of around 155 dB to 170 dB. [17] Range extenders for LoRa are called LoRaX.

LoRaWAN

Since LoRa defines the lower, physical, layer, the upper networking layers were lacking. LoRaWAN is a protocol that was developed to define the upper layers of the network. LoRaWAN is a cloud-based medium access control (MAC) layer protocol, but acts mainly as a network layer protocol for managing communication between LPWAN gateways and end-node devices, as a routing protocol maintained by the LoRa Alliance.

LoRaWAN defines the communication protocol and system architecture for the network, while LoRa's physical layer enables the long-range communication link. LoRaWAN is also responsible for managing the communication frequencies, data rate, and power for all devices. [18] Devices in the network are asynchronous and transmit when 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 centralized network server. [19] Data is then forwarded to application servers. [20] [21] This technology shows high reliability for the moderate load, however, it has some performance issues with sending acknowledgements. [22]

CSMA for LoRaWAN

In the wireless communication, particularly across the IoT applications, collision avoidance is essential for reliable communication and overall spectral efficiency. Previously, LoRaWAN has relied upon ALOHA as the medium access control (MAC) layer protocol, but to improve this, the LoRa Alliance's Technical Recommendation TR013 [23] introduced CSMA-CA, which does not debilitate LoRa's distinctive modulation advantages such as Spreading Factor orthogonality, [15] and the capability for below noise-floor communication. [15] Employing the CAD based CSMA technique specified in TR013 [23] overcomes the limitations of relying on Received Signal Strength (RSS)-based sensing, which is unable to maintain the two said advantages of LoRa modulation. Therefore, implementing TR013 enhances LoRaWAN's spectrum efficiency and ensures more reliable device communication, including in congested environments. [23] TR013 is based on the LMAC [24] and is the first industry-academia collaboration of LoRa Alliance to have resulted in a Technical Recommendation. [25] [26]

Version history

LoRa Alliance

The LoRa Alliance is an open, non-profit association whose stated mission is to support and promote the global adoption of the LoRaWAN standard for massively scaled IoT deployments, as well as deployments in remote or hard-to-reach locations.

Members collaborate in a vibrant ecosystem of device makers, solution providers, system integrators and network operators, delivering interoperability needed to scale IoT across the globe, using  public, private, hybrid, and community networks. Key areas of focus within the Alliance are Smart Agriculture, Smart Buildings, Smart Cities, Smart Industry, Smart Logistics, and Smart Utilities.

Key contributing members of the LoRa Alliance include Actility, Amazon Web Services, Cisco. Everynet, Helium, Kerlink, MachineQ, a Comcast Company, Microsoft, MikroTik, Minol Zenner, Netze BW, Semtech, Senet, STMicroelectronics, TEKTELIC and The Things Industries. [34] In 2018, the LoRa Alliance had over 100 LoRaWAN network operators in over 100 countries; in 2023, there are nearly 200, providing coverage in nearly every country in the world. [35]

See also

Related Research Articles

<span class="mw-page-title-main">IEEE 802.11</span> Wireless network standard

IEEE 802.11 is part of the IEEE 802 set of local area network (LAN) technical standards, and specifies the set of medium access control (MAC) and physical layer (PHY) protocols for implementing wireless local area network (WLAN) computer communication. The standard and amendments provide the basis for wireless network products using the Wi-Fi brand and are the world's most widely used wireless computer networking standards. IEEE 802.11 is used in most home and office networks to allow laptops, printers, smartphones, and other devices to communicate with each other and access the Internet without connecting wires. IEEE 802.11 is also a basis for vehicle-based communication networks with IEEE 802.11p.

<span class="mw-page-title-main">Orthogonal frequency-division multiplexing</span> Method of encoding digital data on multiple carrier frequencies

In telecommunications, orthogonal frequency-division multiplexing (OFDM) is a type of digital transmission used in digital modulation for encoding digital (binary) data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, used in applications such as digital television and audio broadcasting, DSL internet access, wireless networks, power line networks, and 4G/5G mobile communications.

<span class="mw-page-title-main">Wireless LAN</span> Computer network that links devices using wireless communication within a limited area

A wireless LAN (WLAN) is a wireless computer network that links two or more devices using wireless communication to form a local area network (LAN) within a limited area such as a home, school, computer laboratory, campus, or office building. This gives users the ability to move around within the area and remain connected to the network. Through a gateway, a WLAN can also provide a connection to the wider Internet.

<span class="mw-page-title-main">Carrier-sense multiple access with collision avoidance</span> Computer network multiple access method

Carrier-sense multiple access with collision avoidance (CSMA/CA) in computer networking, is a network multiple access method in which carrier sensing is used, but nodes attempt to avoid collisions by beginning transmission only after the channel is sensed to be "idle". When they do transmit, nodes transmit their packet data in its entirety.

In telecommunications and computer networks, a channel access method or multiple access method allows more than two terminals connected to the same transmission medium to transmit over it and to share its capacity. Examples of shared physical media are wireless networks, bus networks, ring networks and point-to-point links operating in half-duplex mode.

Zigbee is an IEEE 802.15.4-based specification for a suite of high-level communication protocols used to create personal area networks with small, low-power digital radios, such as for home automation, medical device data collection, and other low-power low-bandwidth needs, designed for small scale projects which need wireless connection. Hence, Zigbee is a low-power, low-data-rate, and close proximity wireless ad hoc network.

<span class="mw-page-title-main">Power-line communication</span> Type of network

Power-line communication (PLC) is the carrying of data on a conductor that is also used simultaneously for AC electric power transmission or electric power distribution to consumers. The line that does so is known as a power-line carrier.

IEEE 802.15.4 is a technical standard that defines the operation of a low-rate wireless personal area network (LR-WPAN). It specifies the physical layer and media access control for LR-WPANs, and is maintained by the IEEE 802.15 working group, which defined the standard in 2003. It is the basis for the Zigbee, ISA100.11a, WirelessHART, MiWi, 6LoWPAN, Thread, Matter and SNAP specifications, each of which further extends the standard by developing the upper layers, which are not defined in IEEE 802.15.4. In particular, 6LoWPAN defines a binding for the IPv6 version of the Internet Protocol (IP) over WPANs, and is itself used by upper layers such as Thread.

Wireless sensor networks (WSNs) refer to networks of spatially dispersed and dedicated sensors that monitor and record the physical conditions of the environment and forward the collected data to a central location. WSNs can measure environmental conditions such as temperature, sound, pollution levels, humidity and wind.

<span class="mw-page-title-main">Z-Wave</span> Wireless standard for intelligent building networks

Z-Wave is a wireless communications protocol used primarily for residential and commercial building automation. It is a mesh network using low-energy radio waves to communicate from device to device, allowing for wireless control of smart home devices, such as smart lights, security systems, thermostats, sensors, smart door locks, and garage door openers. The Z-Wave brand and technology are owned by Silicon Labs. Over 300 companies involved in this technology are gathered within the Z-Wave Alliance.

IEEE 1901 is a standard for high-speed communication devices via electric power lines, often called broadband over power lines (BPL). The standard uses transmission frequencies below 100 MHz. This standard is usable by all classes of BPL devices, including BPL devices used for the connection to Internet access services as well as BPL devices used within buildings for local area networks, smart energy applications, transportation platforms (vehicle), and other data distribution applications.

<span class="mw-page-title-main">Semtech</span> Business enterprise

Semtech Corporation is a supplier of analog and mixed-signal semiconductors and advanced algorithms for consumer, enterprise computing, communications and industrial end-markets. It is based in Camarillo, Ventura County, Southern California. It was founded in 1960 in Newbury Park, California. It has 32 locations in 15 countries in North America, Europe, and Asia.

IEEE 802.11b-1999 or 802.11b is an amendment to the IEEE 802.11 wireless networking specification that extends throughout up to 11 Mbit/s using the same 2.4 GHz band. A related amendment was incorporated into the IEEE 802.11-2007 standard.

DASH7 Alliance Protocol (D7A) is an open-source wireless sensor and actuator network protocol, which operates in the 433 MHz, 868 MHz and 915 MHz unlicensed ISM/SRD band. DASH7 provides multi-year battery life, range of up to 2 km, low latency for connecting with moving things, a very small open-source protocol stack, AES 128-bit shared-key encryption support, and data transfer of up to 167 kbit/s. The DASH7 Alliance Protocol is the name of the technology promoted by the non-profit consortium called the DASH7 Alliance.

Weightless was a set of low-power wide-area network (LPWAN) wireless technology specifications for exchanging data between a base station and many of machines around it.

IEEE 802.11ah is a wireless networking protocol published in 2017 called Wi-Fi HaLow as an amendment of the IEEE 802.11-2007 wireless networking standard. It uses 900 MHz license-exempt bands to provide extended-range Wi-Fi networks, compared to conventional Wi-Fi networks operating in the 2.4 GHz, 5 GHz and 6 GHz bands. It also benefits from lower energy consumption, allowing the creation of large groups of stations or sensors that cooperate to share signals, supporting the concept of the Internet of things (IoT). The protocol's low power consumption competes with Bluetooth, LoRa, and Zigbee, and has the added benefit of higher data rates and wider coverage range.

A low-power, wide-area network is a type of wireless telecommunication wide area network designed to allow long-range communication at a low bit rate between IoT devices, such as sensors operated on a battery.

Narrowband Internet of things (NB-IoT) is a low-power wide-area network (LPWAN) radio technology standard developed by 3GPP for cellular network devices and services. The specification was frozen in 3GPP Release 13, in June 2016. Other 3GPP IoT technologies include eMTC and EC-GSM-IoT.

Wize technology is a low-power wide-area network technology using the 169 MHz radio frequency. It was created by the Wize Alliance in 2017. Derived from the European Standard Wireless M-Bus, it has mainly been used by utility companies for smart metering infrastructures (AMI) for gas, water and electricity but is equally open to other applications in industry and 'Smart City' spaces.

Static Context Header Compression(SCHC) is a standard compression and fragmentation mechanism defined in the IPv6 over LPWAN working group at the IETF. It offers compression and fragmentation of IPv6/UDP/CoAP packets to allow their transmission over the Low-Power Wide-Area Networks (LPWAN).

References

  1. ↑ "What is LoRa?". Semtech. Retrieved 2021-01-21.
  2. 1 2 "LoRa Modulation Basics" (PDF). Semtech . Archived from the original (PDF) on 2019-07-18. Retrieved 2020-02-05.
  3. ↑ US 9647718,"Wireless communication method",issued 2017-05-09
  4. ↑ "Semtech Acquires Wireless Long Range IP Provider Cycleo". Design And Reuse. Retrieved 2019-10-17.
  5. ↑ "LoRaWAN® recognized as ITU International LPWAN standard". eenewswireless. 8 December 2021. Retrieved 2021-12-31.
  6. ↑ Ferran Adelantado, Xavier Vilajosana, Pere Tuset-Peiro, Borja Martinez, Joan Melià-Seguí and Thomas Watteyne. Understanding the Limits of LoRaWAN (January 2017).
  7. ↑ "RP002-1.0.3 LoRaWAN Regional Parameters" (PDF). lora-alliance.org. Retrieved 9 June 2021.
  8. ↑ Ramon Sanchez-Iborra; Jesus Sanchez-Gomez; Juan Ballesta-Viñas; Maria-Dolores Cano; Antonio F. Skarmeta (2018). "Performance Evaluation of LoRa Considering Scenario Conditions". Sensors. 18 (3): 772. Bibcode:2018Senso..18..772S. doi: 10.3390/s18030772 . PMC   5876541 . PMID   29510524.
  9. ↑ Adelantado, Ferran; Vilajosana, Xavier; Tuset-Peiro, Pere; Martinez, Borja; Melia-Segui, Joan; Watteyne, Thomas (2017). "Understanding the Limits of LoRaWAN". IEEE Communications Magazine. 55 (9): 34–40. doi:10.1109/mcom.2017.1600613. hdl: 10609/93072 . ISSN   0163-6804. S2CID   2798291.
  10. ↑ Micael Coutinho; Jose A. Afonso; Sergio F. Lopes (2023). "An Efficient Adaptive Data-Link-Layer Architecture for LoRa Networks". Future Internet. 15 (8): 273. doi: 10.3390/fi15080273 . hdl: 1822/87237 .
  11. ↑ Fargas, Bernat Carbones; Petersen, Martin Nordal. "GPS-free Geolocation using LoRa in Low-Power WANs" (PDF). DTU Library.
  12. 1 2 "SX1261/2 Datasheet". Semtech SX1276. Semtech. Retrieved 19 November 2021.
  13. ↑ M. Chiani; A. Elzanaty (2019). "On the LoRa Modulation for IoT: Waveform Properties and Spectral Analysis". IEEE Internet of Things Journal. 6 (5): 772. arXiv: 1906.04256 . doi:10.1109/JIOT.2019.2919151. hdl: 10754/655888 . S2CID   184486907.
  14. ↑ Qoitech. "How Spreading Factor affects LoRaWAN device battery life". The Things Network. Retrieved 2020-02-25.
  15. 1 2 3 J.C. Liando; A. Gamage; A.W. Tengourtius; M. Li (2019). "Known and Unknown Facts of LoRa: Experiences from a Large-Scale Measurement Study". ACM Transactions on Sensor Networks. 15 (2): Article No. 16, pp 1–35. doi:10.1145/3293534. hdl: 10356/142869 . ISSN   1550-4859. S2CID   53669421.
  16. ↑ "What are LoRa® and LoRaWAN®?". LoRa Developer Portal. Retrieved 7 July 2021.
  17. ↑ Mohan, Vivek. "10 Things About LoRaWAN & NB-IoT". blog.semtech.com. Retrieved 2019-02-18.
  18. ↑ "LoRaWAN For Developers". www.lora-alliance.org. Retrieved 2018-11-23.
  19. ↑ "A Comprehensive Look At LPWAN For IoT Engineers & Decision Makers". www.link-labs.com. Retrieved 2017-06-22.
  20. ↑ LoRa Alliance (2015). "LoRaWAN: What is it?" (PDF).
  21. ↑ Example of LoRaWan IoT end device transmitting data. Cloud Studio platform used: https://gear.cloud.studio/gear/monitor/shared-dashboard/88c96030a42c4a1fa2669286a6bde321
  22. ↑ Bankov, D.; Khorov, E.; Lyakhov, A. (November 2016). "On the Limits of LoRaWAN Channel Access". 2016 International Conference on Engineering and Telecommunication (EnT). pp. 10–14. doi:10.1109/ent.2016.011. ISBN   978-1-5090-4553-2. S2CID   44799707.
  23. 1 2 3 "Enabling CSMA for LoRaWAN TR013-1.0.0". LoRa Alliance. Retrieved 2023-11-05.
  24. ↑ Gamage, Amalinda; Liando, Jansen; Gu, Chaojie; Tan, Rui; Li, Mo; Seller, Olivier (2023-05-31). "LMAC: Efficient Carrier-Sense Multiple Access for LoRa". ACM Transactions on Sensor Networks. 19 (2): 1–27. doi:10.1145/3564530. ISSN   1550-4859.
  25. ↑ Jathun, Gamage Isuru Amalinda (2023). Optimizing spectral utilization of LPWANs (Thesis). Nanyang Technological University. doi: 10.32657/10356/172897 .
  26. ↑ LoRa Alliance (2024-02-01). LoRaWAN® CSMA to Minimize on Air Collisions . Retrieved 2024-07-13– via YouTube.
  27. ↑ "LoRaWAN Specification" (PDF). lora-alliance.org. Retrieved 5 February 2020.
  28. ↑ Version 1.0 of the LoRaWAN specification released.
  29. ↑ "LoRaWAN Specification". lora-alliance.org. Retrieved 2 February 2021.
  30. ↑ "LoRaWAN Specification" (PDF). lora-alliance.org. Retrieved 5 February 2020.
  31. ↑ "LoRaWAN™ 1.1 Specification" (PDF). lora-alliance.org. Retrieved 5 February 2020.
  32. ↑ "LoRaWAN 1.0.3 Specification" (PDF). lora-alliance.org. Retrieved 5 February 2020.
  33. ↑ "LoRaWAN 1.0.4 Specification". lora-alliance.org. Retrieved 25 November 2020.
  34. ↑ "Member Directory | LoRa Alliance". lora-alliance.org. Retrieved May 22, 2023.
  35. ↑ "LoRa Alliance passes 100 LoRaWAN network operator milestone". Electronic Products & Technology. 2019-01-25. Retrieved 2019-02-11.

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.