- Source: LoRa
LoRa (from "Long Range") is a physical proprietary radio communication technique. It is based on spread spectrum modulation techniques derived from chirp spread spectrum (CSS) technology. It was developed by Cycleo, a company of Grenoble, France, and patented in 2014. Cycleo was later acquired by Semtech.
LoRaWAN (Long Range 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. 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.
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; LoRa enables long-range transmissions with low power consumption. The technology covers the physical layer, while other technologies and protocols such as LoRaWAN cover the upper layers. It can achieve data rates between 0.3 kbit/s and 27 kbit/s, depending upon the spreading factor.
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.
LoRa devices have geolocation capabilities used for trilaterating positions of devices via timestamps from gateways.
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 (
f
0
−
B
/
2
,
f
0
+
B
/
2
{\displaystyle f_{0}-B/2,f_{0}+B/2}
) where
f
0
{\displaystyle f_{0}}
is the center frequency and
B
{\displaystyle B}
the bandwidth of the signal (in Hertz). The spreading factor (SF) is a selectable radio parameter from 5 to 12 and represents the number of symbols sent per bit and in addition determines how much the information is spread over time. There are
M
=
2
S
F
{\displaystyle M=2^{\mathrm {SF} }}
different initial frequencies of the cyclic shifted chirp (the instantaneous frequency is linearly increased and wrapped to
f
0
−
B
/
2
{\displaystyle f_{0}-B/2}
when it reaches the maximum frequency
f
0
+
B
/
2
{\displaystyle f_{0}+B/2}
). The symbol rate is determined by
R
s
=
B
/
2
S
F
{\displaystyle R_{s}=B/2^{\mathrm {SF} }}
. LoRa can trade off data rate for sensitivity (assuming a fixed channel bandwidth
B
{\displaystyle B}
) 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. 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. 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. 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).
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. 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. 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. Data is then forwarded to application servers. This technology shows high reliability for the moderate load, however, it has some performance issues with sending acknowledgements.
= 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 introduced CSMA-CA, which does not debilitate LoRa's distinctive modulation advantages such as Spreading Factor orthogonality, and the capability for below noise-floor communication. Employing the CAD based CSMA technique specified in TR013 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. TR013 is based on the LMAC and is the first industry-academia collaboration of LoRa Alliance to have resulted in a Technical Recommendation.
= Version history
=
January 2015: 1.0
February 2016: 1.0.1
July 2016: 1.0.2
October 2017: 1.1, adds Class B
July 2018: 1.0.3
October 2020: 1.0.4
= 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. 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.
On October 1, 2024, Cisco announced it is "exiting the LoRaWAN space" with no planned migration for Cisco LoRaWAN gateways.
See also
DASH7 — a popular open alternative to LoRa
IEEE 802.11ah — non-proprietary low-power long-range standard
CC430 — an MCU & sub-1 GHz RF transceiver SoC
NB-IoT — Narrowband Internet of Things
LTE Cat M1 – Cellular device technology
MIoTy — sub-GHz LPWAN technology for sensor networks
SCHC — static context header compression
Short-range device – Class of radio transmitter
Helium (cryptocurrency) — LoRaWAN protocol paired with blockchain technology
Amazon Sidewalk — A mesh wireless network developed by Amazon
Meshtastic — A popular open source mesh network protocol that uses LoRa
References
Further reading
Olivier Bernard André Seller. "Wireless communication method" U.S. Patent No. 9,647,718. 9 September 2015.
Lee, Chang-Jae, Ki-Seon Ryu, and Beum-Joon Kim. "Periodic ranging in a wireless access system for mobile station in sleep mode." U.S. Patent No. 7,194,288. 20 March 2007.
Ghoslya, Sakshama (2019-04-17). "How to generate LoRa Symbols". All About LoRa and LoRaWAN.
Quigley, Thomas J., and Ted Rabenko. "Latency reduction in a communications system." U.S. Patent No. 7,930,000. 19 April 2011.
Bankov, D.; Khorov, E.; Lyakhov, A. "On the Limits of LoRaWAN Channel Access". 2016 International Conference on Engineering and Telecommunication (EnT): 10–14.
Seneviratne, Pradeeka. "Beginning LoRa Radio Networks with Arduino - Build Long Range, Low Power Wireless IoT Networks." Apress, 2019, eBook ISBN 978-1-4842-4357-2, Softcover ISBN 978-1-4842-4356-5, Ed: 1
External links
LoRa Alliance
LoRa Developer Portal
Cycleo website at the Wayback Machine (archived 2011-07-29)- Source: Lora
Lora is a female given name and family name in the Spanish language of French origin meaning from Lorraine, a region in Northeastern France.
As a given name, Lora may also be a variant of Laura or derived from an Italian hypocoristic of either Eleonora or Loredana.
People with the given name Lora
Lora (singer) (born 1982), Romanian singer
Lora Aborn (1907–2005), American composer
Lora Aroyo, Dutch computer scientist
Lora Beldon, American artist-curator
Lora Haines Cook (1866–1946), American civic leader
Lora L. Corum (1899-1949), American co-winner
Lora Dimitrova (born 1962), Bulgarian Pianist
Lora Fachie (born 1988), English racing cyclist
Lora Fairclough (born 1970), English professional golfer
Lora Lee Gayer (born 1988), American actress
Lora Grosu (born 1959), Moldovan politician
Lora Hirschberg (born 1963), American sound engineer
Lora Hooper, American biologist
Lora Hubbel, American politician
Lora Johnson, American author
Lora Lazar, Bulgarian crime writer
Lora Leigh (born 1965), American author
Lora Logic (born 1960), British saxophonist
Lora La Mance (1857–1939), American writer
Lora Marx (1900-1989), American sculptor
Lora Lee Michel (born 1940), American actress
Lora Ottenad (born 1964), American professional bodybuilder
Lora Petrova (born 1998), Bulgarian footballer
Lora Reinbold (born 1964), American politician
Lora Romero (1960-1997), American assistant professor
Lora Storey (born 1989), Australian middle-distance runner
Lora Webster (born 1986), American Paralympic volleyballist
Lora Yakovleva (born 1932), Russian chess grandmaster
People with the surname Lora
Alan Loras, Bolivian footballer
Alberto Lora Ramos (born 1987), Spanish football player
Alex Lora (born 1952), Mexican musician and composer
Carmen Josefina Lora Iglesias (1940 – 1999), Dominican revolutionary and lawyer
Enrique Lora (born 1945), Spanish footballer
Fabiano Bolla Lora (born 1977), Brazilian footballer
Filippo Lora (born 1993), Italian footballer
Francisco Augusto Lora, Dominican politician
Guillermo Lora (1922-2009), Bolivian Trotskyist
Johan Lora (born 1982), Dominican footballer
Luis Eduardo Lora (born 1986), Colombian footballer
Mathias Loras (1792-1858), French priest
Manny Lora (born 1991), American baseball player and coach
Marie Lora-Mungai, French producer, writer and show runner
Miguel "Happy" Lora (born 1961), Colombian boxer
Ñico Lora (1880-1971), Dominican, father of Merengue music
Saturnino and Mariano Lora, Cuban brothers, war heroes
Yelitza Lora, Dominican television and radio host and actress
Places
Lora (Lydia), a town of ancient Lydia, now in Turkey
Lora, Norway, a village in Lesja municipality in Oppland
Lora, Chile a town on the Mataquito River, Chile
Lora, a frazioni in the municipality of Campegine, Italy
Lora (Split), a neighborhood and naval base in Split, Croatia
Lora, Khyber Pakhtunkhwa, a village and union council in Pakistan
Lora River, Pakistan
Lora de Estepa, a municipality in the province of Seville, Spain
Lora del Río, a municipality in the province of Seville, Spain
Loras College, a four-year Catholic university located in Dubuque, Iowa
Falls of Lora, a tidal race which forms at the mouth of Loch Etive, Scotland
Sargentes de la Lora, a municipality located in the province of Burgos, Castile and León, Spain.
Animals
Lora or Leptophis ahaetulla, a Parrot Snake found in northern South America and Trinidad and Tobago
Grey Lora or Leptophis stimsoni, a small snake which is endemic to Trinidad and Tobago
Lora (genus), a gastropod genus of the Turridae family
Technology
LORA (missile), a theatre quasiballistic missile produced in Israel
LORA, an acronym for Level of Repair Analysis
LoRa, a long-range low-power wireless communication technology over radio frequencies
LORA, an acronym for "Logic Of Rational Agents", see BDI Software Agents
LoRA, an acronym for "Low-Rank Adaptation". A technique for efficiently finetuning machine learning models.
Other
Lora, an Ancient Roman term for a wine substitute later known as piquette
Lora (film), a 2007 Hungarian film
See also
All pages with titles beginning with Lora
All pages with titles containing Lora
Laura (disambiguation)
Lota (name)
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