Li-Fi (Light Fidelity): cos'è e come funziona la connessione via LED
Basandosi sulla comunicazione a luce visibile e modulando l'intensità dei singoli LED, la tecnologia Li-Fi è in grado di trasmettere una grande ...
Visible Light Communication
Il Li-Fi è quindi una forma di comunicazione a luce visibile riconducibile alle comunicazioni wireless ottiche (OWC). Il termine fu utilizzato per la prima volta nel 2011 da un professore dell’Università di Edimburgo, Harald Haas, durante un intervento sulla <anchor>Visible Light Communication</anchor> al TED Global, l’annuale conferenza americana dedicata a innovazione e creatività.
Visible light communication - Wikipedia
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## Contents

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- (Top)

- [1Uses](#Uses)
- [2History](#History)
- [3Modulation Techniques](#Modulation_Techniques)Toggle Modulation Techniques subsection  - [3.1Single-Carrier Modulated Transmission](#Single-Carrier_Modulated_Transmission)
  - [3.2Multi-Carrier Modulated Transmission](#Multi-Carrier_Modulated_Transmission)
  - [3.3Pulse-Based Transmission](#Pulse-Based_Transmission)    - [3.3.1On-Off Keying](#On-Off_Keying)
    - [3.3.2Variable Pulse Position Modulation](#Variable_Pulse_Position_Modulation)
    - [3.3.3Color Shift Keying](#Color_Shift_Keying)
- [4See also](#See_also)
- [5References](#References)
- [6Further reading](#Further_reading)
- [7External links](#External_links)

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# Visible light communication

10 languages

- [العربية](https://ar.wikipedia.org/wiki/%D8%A7%D8%AA%D8%B5%D8%A7%D9%84%D8%A7%D8%AA_%D8%A7%D9%84%D8%B6%D9%88%D8%A1_%D8%A7%D9%84%D9%85%D8%B1%D8%A6%D9%8A "اتصالات الضوء المرئي – Arabic")
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- [日本語](https://ja.wikipedia.org/wiki/%E5%8F%AF%E8%A6%96%E5%85%89%E9%80%9A%E4%BF%A1 "可視光通信 – Japanese")
- [Русский](https://ru.wikipedia.org/wiki/VLC_(%D1%82%D0%B5%D1%85%D0%BD%D0%BE%D0%BB%D0%BE%D0%B3%D0%B8%D1%8F_%D0%BF%D0%B5%D1%80%D0%B5%D0%B4%D0%B0%D1%87%D0%B8_%D0%B4%D0%B0%D0%BD%D0%BD%D1%8B%D1%85) "VLC (технология передачи данных) – Russian")
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From Wikipedia, the free encyclopedia

Use of light in the visible spectrum as a telecommunication medium

[![](//upload.wikimedia.org/wikipedia/commons/thumb/f/f1/EM_spectrum.svg/390px-EM_spectrum.svg.png)](/wiki/File:EM_spectrum.svg) Visible light is only a small portion of the [electromagnetic spectrum](/wiki/Electromagnetic_spectrum "Electromagnetic spectrum").

In [telecommunications](/wiki/Telecommunications "Telecommunications"), **visible light communication** ( **VLC**) is the use of [visible light](/wiki/Visible_spectrum "Visible spectrum") ( [light](/wiki/Light "Light") with a [frequency](/wiki/Frequency "Frequency") of 400–800 [THz](/wiki/Hertz "Hertz")/ [wavelength](/wiki/Wavelength "Wavelength") of 780–375 [nm](/wiki/Nanometre "Nanometre")) as a [transmission medium](/wiki/Transmission_medium "Transmission medium"). VLC is a subset of [optical wireless communications](/wiki/Optical_wireless_communications "Optical wireless communications") technologies.

The technology uses [fluorescent lamps](/wiki/Fluorescent_lamp "Fluorescent lamp") (ordinary lamps, not special communications devices) to transmit signals at 10 [kbit/s](/wiki/Kbit/s "Kbit/s"), or [LEDs](/wiki/LED "LED") for up to 500 Mbit/s over short distances. Systems such as [RONJA](/wiki/RONJA "RONJA") can transmit at full [Ethernet](/wiki/Ethernet "Ethernet") speed (10 Mbit/s) over distances of 1–2 kilometres (0.6–1.2 mi).

Specially designed electronic devices generally containing a [photodiode](/wiki/Photodiode "Photodiode") receive signals from light sources,[\[1\]](#cite_note-vlcc-sensor-1) although in some cases a [cell phone camera](/wiki/Camera_phone "Camera phone") or a [digital camera](/wiki/Digital_camera "Digital camera") will be sufficient.[\[2\]](#cite_note-vlcc-about-2) The image sensor used in these devices is in fact an array of photodiodes (pixels) and in some applications its use may be preferred over a single photodiode. Such a sensor may provide either multi-channel (down to 1 pixel = 1 channel) or a spatial awareness of multiple light sources.[\[1\]](#cite_note-vlcc-sensor-1)

VLC can be used as a communications medium for [ubiquitous computing](/wiki/Ubiquitous_computing "Ubiquitous computing"), because light-producing devices (such as indoor/outdoor lamps, TVs, traffic signs, commercial displays and car [headlights/taillights](/wiki/Automotive_lighting "Automotive lighting")[\[3\]](#cite_note-vlcc-its-3)) are used everywhere.[\[2\]](#cite_note-vlcc-about-2)

## Uses

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=1 "Edit section: Uses")\]

One of the main characteristics of VLC is the incapacity of light to surpass physical opaque barriers. This characteristic can be considered a weak point of VLC, due to the susceptibility of interference from physical objects, but is also one of its many strengths: unlike radio waves, light waves are confined in the enclosed spaces they are transmitted, which enforces a physical safety barrier that requires a receptor of that signal to have physical access to the place where the transmission is occurring.[\[4\]](#cite_note-:4-4)

A promising application of VLC is the [Indoor Positioning System](/wiki/Indoor_positioning_system "Indoor positioning system") (IPS), an analogue to GPS which is built to operate in enclosed spaces where GPS satellite transmissions cannot reach. For instance, commercial buildings, shopping malls, parking garages, as well as subways and tunnel systems are all possible applications for VLC-based indoor positioning systems. Additionally, once the VLC lamps are able to perform lighting at the same time as data transmission, it can simply occupy the installation of traditional single-function lamps.

Other applications for VLC involve communication between appliances of a smart home or office. With increasing [IoT](/wiki/Internet_of_things "Internet of things")-capable devices, connectivity through traditional radio waves might be subjected to interference.[\[5\]](#cite_note-5) Light bulbs with VLC capabilities can transmit data and commands for such devices.

## History

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=2 "Edit section: History")\]

The history of visible light communications dates back to the 1880s in [Washington, D.C.](/wiki/Washington,_D.C. "Washington, D.C."), when the Scottish-born scientist [Alexander Graham Bell](/wiki/Alexander_Graham_Bell "Alexander Graham Bell") invented the [photophone](/wiki/Photophone "Photophone"), which transmitted speech on modulated [sunlight](/wiki/Sunlight "Sunlight") over several hundred meters. This pre-dates the transmission of speech by radio.

More recent work began in 2003 at Nakagawa Laboratory, in [Keio University](/wiki/Keio_University "Keio University"), [Japan](/wiki/Japan "Japan"), using [LEDs](/wiki/LEDs "LEDs") to transmit data by visible light. Since then there have been numerous research activities focussed on VLC.

In 2006, researchers from CICTR at [Penn State](/wiki/Penn_State "Penn State") proposed a combination of [power line communication](/wiki/Power_line_communication "Power line communication") (PLC) and white light LED to provide broadband access for indoor applications.[\[6\]](#cite_note-6) This research suggested that VLC could be deployed as a perfect last-mile solution in the future.

In January 2010 a team of researchers from [Siemens](/wiki/Siemens "Siemens") and [Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute](/wiki/Fraunhofer_Institute_for_Telecommunications "Fraunhofer Institute for Telecommunications"), in Berlin, demonstrated transmission at 500 Mbit/s with a white LED over a distance of 5 metres (16 ft), and 100 Mbit/s over longer distance using five LEDs.[\[7\]](#cite_note-7)

The VLC standardization process is conducted within the [IEEE 802.15.7](/wiki/IEEE_802.15#IEEE_802.15.7:_Visible_Light_Communication "IEEE 802.15") working group.

In December 2010 [St. Cloud, Minnesota](/wiki/St._Cloud,_Minnesota "St. Cloud, Minnesota"), signed a contract with [LVX](/wiki/LVX "LVX") [\[1\]](http://www.lvx-system.com) Minnesota and became the first to commercially deploy this technology.[\[8\]](#cite_note-8)

In July 2011 a presentation at [TED Global](/wiki/TED_(conference) "TED (conference)")[\[9\]](#cite_note-9) gave a live demonstration of [high-definition video](/wiki/High-definition_video "High-definition video") being transmitted from a standard LED lamp, and proposed the term [Li-Fi](/wiki/Li-Fi "Li-Fi") to refer to a subset of VLC technology.

Recently, VLC-based [indoor positioning systems](/wiki/Indoor_positioning_systems "Indoor positioning systems") have become an attractive topic. ABI research forecasts that it could be a key solution to unlocking the $5 billion "indoor location market".[\[10\]](#cite_note-10) Publications have been coming from Nakagawa Laboratory,[\[11\]](#cite_note-11) ByteLight filed a patent[\[12\]](#cite_note-12) on a light positioning system using LED digital pulse recognition in March 2012.[\[13\]](#cite_note-13)[\[14\]](#cite_note-14) COWA at Penn State[\[15\]](#cite_note-15)[\[16\]](#cite_note-16) and other researchers around the world.[\[17\]](#cite_note-17)[\[18\]](#cite_note-18)

Another recent application is in the world of toys, thanks to cost-efficient and low-complexity implementation, which only requires one [microcontroller](/wiki/Microcontroller "Microcontroller") and one LED as optical front-end.[\[19\]](#cite_note-19)

VLCs can be used for providing security.[\[20\]](#cite_note-20)[\[21\]](#cite_note-21) They are especially useful in body sensor networks and personal area networks.

Recently Organic LEDs ( [OLED](/wiki/OLED "OLED")) have been used as optical transceivers to build up VLC communication links up to 10 Mbit/s.[\[22\]](#cite_note-22)

In October 2014, Axrtek launched a commercial bidirectional RGB LED VLC system called MOMO that transmits down and up at speeds of 300 Mbit/s and with a range of 25 feet.[\[23\]](#cite_note-23)

In May 2015, Philips collaborated with supermarket company Carrefour to deliver VLC location-based services to shoppers' smartphones in a hypermarket in [Lille, France](/wiki/Lille,_France "Lille, France").[\[24\]](#cite_note-24) In June 2015, two Chinese companies, [Kuang-Chi](/wiki/Kuang-Chi "Kuang-Chi") and [Ping An Bank](/wiki/Ping_An_Bank "Ping An Bank"), partnered to introduce a payment card that communicates information through a unique visible light.[\[25\]](#cite_note-25)
In March 2017, Philips set up the first VLC location-based services to shoppers' smartphones in Germany. The installation was presented at EuroShop in Düsseldorf (5–9 March). As first supermarket in Germany an Edeka supermarket in Düsseldorf-Bilk is using the system, which offers a 30 centimeter positioning accuracy can be achieved, which meets the special demands in food retail.[\[26\]](#cite_note-26)[\[27\]](#cite_note-27) Indoor positioning systems based on VLC[\[28\]](#cite_note-28) can be used in places such as hospitals, eldercare homes, warehouses, and large, open offices to locate people and control indoor robotic vehicles.

There is wireless network that for data transmission uses visible light, and does not use intensity modulation of optical sources. The idea is to use vibration generator instead of optical sources for data transmission.[\[29\]](#cite_note-29)

## Modulation Techniques

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=3 "Edit section: Modulation Techniques")\]

In order to send data, a modulation of light is required. A modulation is the form in which the light signal varies in order to represent different symbols. In order for the data to be decoded. Unlike [radio transmission](/wiki/Radio_transmission "Radio transmission"), a VLC modulation requires the light signal to be modulated around a positive dc value, responsible for the lighting aspect of the lamp. The modulation will thus be an alternating signal around the positive dc level, with a high-enough frequency to be imperceptible to the human eye.[\[30\]](#cite_note-:0-30)

Due to this superposition of signals, implementation of VLC transmitter usually require a high-efficiency, higher-power, slower response DC converter responsible for the LED bias that will provide lighting, alongside a lower-efficiency, lower-power, but higher response velocity amplifier in order to synthesize the required AC current modulation.

There are several modulation techniques available, forming three main groups:[\[31\]](#cite_note-31) Single-Carrier Modulated Transmission (SCMT), Multi-Carrier Modulated Transmission (MCMT) and Pulse-Based Transmission (PBT).

### Single-Carrier Modulated Transmission

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=4 "Edit section: Single-Carrier Modulated Transmission")\]

The Single-Carrier Modulated Transmission comprises modulation techniques established for traditional forms of transmission, such as radio. A sinusoidal wave is added to the lighting dc level, allowing digital information to be coded in the characteristics of the wave. By keying between two or several different values of a given characteristic, symbols attributed to each value are transmitted on the light link.

Possible techniques are Amplitude Switch Keying (ASK), Phase Switch Keying (PSK) and Frequency Switch Keying (FSK). Out of these three, FSK is capable of larger bitrate transmission once it allows more symbols to be easily differentiated on frequency switching. An additional technique called [Quadrature Amplitude Modulation](/wiki/Quadrature_amplitude_modulation "Quadrature amplitude modulation") (QAM) has also been proposed, where both amplitude and phase of the sinusoidal voltage are keyed simultaneously in order to increase the possible number of symbols.[\[30\]](#cite_note-:0-30)

### Multi-Carrier Modulated Transmission

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=5 "Edit section: Multi-Carrier Modulated Transmission")\]

Multi-Carrier Modulated Transmission works on the same way of Single-Carrier Modulated Transmission methods, but embed two or more sinusoidal waves modulated for data transmission.[\[32\]](#cite_note-32) This type of modulation is among the hardest and more complex to synthesize and decode. However, it presents the advantage of excelling in multipath transmission, where the receptor is not in direct view of the transmitter and therefore makes the transmission depend on reflection of the light in other barriers.

### Pulse-Based Transmission

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=6 "Edit section: Pulse-Based Transmission")\]

Pulse-Based transmission encompasses modulation techniques in which the data is encoded not on a sinusoidal wave, but on a pulsed wave. Unlike sinusoidal alternating signals, in which the periodic average will always be null, pulsed waves based on high-low states will present inherit average values. This brings two main advantages for the Pulse-Based Transmission modulations:

It can be implemented with a single high-power, high-efficiency, dc converter of slow response and an additional power switch operating in fast speeds to deliver current to the LED at determined instants.
Once the average value depends on the pulse width of the data signal, the same switch that operates the data transmission can provide dimming control, greatly simplifying the dc converter.

Due to these important implementation advantages, these dimming-capable modulations have been standardized in [IEEE 802.15.7](/wiki/IEEE_802.15#IEEE_802.15.7:_Visible_Light_Communication "IEEE 802.15"), in which are described three modulation techniques: On-Off Keying (OOK), Variable Pulse Position Modulation (VPPM) and Color Shift Keying (CSK).

#### On-Off Keying

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=7 "Edit section: On-Off Keying")\]

On the [On-Off Keying](/wiki/On%E2%80%93off_keying "On–off keying") technique, the LED is switched on and off repeatedly, and the symbols are differentiated by the pulse width, with a wider pulse representing the logical high '1', while narrower pulses representing logical low '0'. Because the data is encoded on the pulse width, the information sent will affect the dimming level if not corrected: for instance, a bitstream with several high values '1' will appear brighter than a bitstream with several low values '0'. In order to fix this problem, the modulation requires a compensation pulse that will be inserted on the data period whenever necessary to equalize the brightness overall. The lack of this compensation symbol could introduce perceived flickering, which is undesirable.

Because of the additional compensation pulse, modulating this wave is slightly more complex than modulating the VPPM. However, the information encoded on the pulse width is easy to differentiate and decode, so the complexity of the transmitter is balanced by the simplicity of the receiver.

#### Variable Pulse Position Modulation

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=8 "Edit section: Variable Pulse Position Modulation")\]

Variable Pulse Position also switches the LED on and off repeatedly, but encode the symbols on the pulse position inside the data period. Whenever the pulse is located at the immediate beginning of the data period, the transmitted symbol is standardized as logical low '0', with logical high '1' being composed of pulses that end with the data period. Because the information is encoded at the location of the pulse inside the data period, both pulses can and will have the same width, and thus, no compensation symbol is required. Dimming is performed by the transmitting algorithm, that will select the width of the data pulses accordingly.

The lack of a compensation pulse makes VPPM marginally simpler to encode when compared to OOK. However, a slightly more complex demodulation compensates for that simplicity on the VPPM technique. This decoding complexity mostly comes from the information being encoded at different rising edges for each symbol, which makes the sampling harder in a microcontroller. Additionally, in order to decode the location of a pulse within the data period, the receptor must be somehow synchronized with the transmitter, knowing exactly when a data period starts and how long it lasts. These characteristics makes the demodulation of a VPPM signal slightly more difficult to implement.

#### Color Shift Keying

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=9 "Edit section: Color Shift Keying")\]

Color shift keying (CSK), outlined in IEEE 802.15.7, is an [intensity modulation](/wiki/Intensity_modulation "Intensity modulation") based modulation scheme for VLC. CSK is intensity-based, as the modulated signal takes on an instantaneous color equal to the physical sum of three (red/green/blue) LED instantaneous intensities. This modulated signal jumps instantaneously, from symbol to symbol, across different visible colors; hence, CSK can be construed as a form of frequency shifting. However, this instantaneous variation in the transmitted color is not to be humanly perceptible, because of the limited temporal sensitivity in the human vision — the "critical [flicker fusion threshold](/wiki/Flicker_fusion_threshold "Flicker fusion threshold")" (CFF) and the "critical color fusion threshold" (CCF), both of which cannot resolve temporal changes shorter than 0.01 second. The LEDs’ transmissions are, therefore, preset to time-average (over the CFF and the CCF) to a specific time-constant color. Humans can thus perceive only this preset color that seems constant over time, but cannot perceive the instantaneous color that varies rapidly in time. In other words, CSK transmission maintains a constant time-averaged luminous flux, even as its symbol sequence varies rapidly in [chromaticity](/wiki/Chromaticity "Chromaticity").[\[33\]](#cite_note-33)

## See also

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=10 "Edit section: See also")\]

- [Electric beacon](/wiki/Electric_beacon "Electric beacon")
- [Fiber-optic communication](/wiki/Fiber-optic_communication "Fiber-optic communication")
- [Free space optics](/wiki/Free_space_optics "Free space optics")
- [Free-space optical communication](/wiki/Free-space_optical_communication "Free-space optical communication")
- [IrDA](/wiki/Infrared_Data_Association "Infrared Data Association")—Same principle as VLC but uses [infrared](/wiki/Infrared "Infrared") light instead of visible light
- [Li-Fi](/wiki/Li-Fi "Li-Fi")
- [Optical wireless communications](/wiki/Optical_wireless_communications "Optical wireless communications")
- [RONJA](/wiki/RONJA "RONJA")

## References

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=11 "Edit section: References")\]

01. ^ [_**a**_](#cite_ref-vlcc-sensor_1-0) [_**b**_](#cite_ref-vlcc-sensor_1-1)["Image Sensor Communication"](http://www.vlcc.net/modules/pico2/index.php?content_id=28). VLC Consortium.\[ _[dead link](/wiki/Wikipedia:Link_rot "Wikipedia:Link rot")_\]
02. ^ [_**a**_](#cite_ref-vlcc-about_2-0) [_**b**_](#cite_ref-vlcc-about_2-1)["About Visible Light Communication"](https://web.archive.org/web/20091203082619/http://www.vlcc.net/modules/pico2/index.php?content_id=1). VLC Consortium. Archived from [the original](http://www.vlcc.net/modules/pico2/index.php?content_id=1) on December 3, 2009.
03. **[^](#cite_ref-vlcc-its_3-0)**["Intelligent Transport System – Visible Light Communication"](https://web.archive.org/web/20100128023152/http://www.vlcc.net/modules/pico2/index.php?content_id=4). VLC Consortium. Archived from [the original](http://www.vlcc.net/modules/pico2/index.php?content_id=4) on January 28, 2010.
04. **[^](#cite_ref-:4_4-0)**Dimitrov, Svilen; Haas, Harald (2015). [_Principles of LED Light Communications: Towards Networked Li-Fi_](https://www.cambridge.org/core/books/principles-of-led-light-communications/0528063BAA6863F6B6D61F6FF69F37CB). Cambridge: Cambridge University Press. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1017/cbo9781107278929](https://doi.org/10.1017%2Fcbo9781107278929). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-107-04942-0](/wiki/Special:BookSources/978-1-107-04942-0 "Special:BookSources/978-1-107-04942-0").
05. **[^](#cite_ref-5)**["Cisco Annual Internet Report - Cisco Annual Internet Report (2018–2023) White Paper"](https://www.cisco.com/c/en/us/solutions/collateral/executive-perspectives/annual-internet-report/white-paper-c11-741490.html). _Cisco_. Retrieved 2020-10-21.
06. **[^](#cite_ref-6)**M. Kavehrad, P. Amirshahi, "Hybrid MV-LV Power Lines and White Light Emitting Diodes for Triple-Play Broadband Access Communications," IEC Comprehensive Report on Achieving the Triple Play: Technologies and Business Models for Success, [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [1-931695-51-2](/wiki/Special:BookSources/1-931695-51-2 "Special:BookSources/1-931695-51-2"), pp. 167-178, January 2006. [See publication here](http://cictr.ee.psu.edu/research/wc/IEC-White-LED-Triple-Play.pdf) [Archived](https://web.archive.org/web/20160304081252/http://cictr.ee.psu.edu/research/wc/IEC-White-LED-Triple-Play.pdf) 2016-03-04 at the [Wayback Machine](/wiki/Wayback_Machine "Wayback Machine")
07. **[^](#cite_ref-7)**["500 Megabits/Second with White LED Light"](https://web.archive.org/web/20120929044003/http://www.siemens.com/innovation/en/news/2010/500-megabits-second-with-white-led-light.htm) (Press release). Siemens. January 18, 2010. Archived from [the original](https://www.siemens.com/innovation/en/news/2010/500-megabits-second-with-white-led-light.htm) on September 29, 2012. Retrieved June 21, 2012.
08. **[^](#cite_ref-8)**["St. Cloud first to sign on for new technology"](http://smart-grid.tmcnet.com/news/2010/11/19/5148608.htm) (Press release). St. Cloud Times. Nov 19, 2010.
09. **[^](#cite_ref-9)**["Wireless data from every light bulb"](https://www.ted.com/talks/harald_haas_wireless_data_from_every_light_bulb). 2 August 2011.
10. **[^](#cite_ref-10)**["LED and Visible Light Communications Could be Key to Unlocking $5 Billion Indoor Location Market"](https://www.abiresearch.com/press/led-and-visible-light-communications-could-be-key-). _www.abiresearch.com_.
11. **[^](#cite_ref-11)**Yoshino, M.; Haruyama, S.; Nakagawa, M.; "High-accuracy positioning system using visible LED lights and image sensor," Radio and Wireless Symposium, 2008 IEEE, vol., no., pp.439-442, 22-24 Jan. 2008.
12. **[^](#cite_ref-12)**["Light positioning system using digital pulse recognition"](https://patents.google.com/patent/US8248467).
13. **[^](#cite_ref-13)**Yoshino, Masaki; Haruyama, Shinichiro; Nakagawa, Masao (1 January 2008). "High-accuracy positioning system using visible LED lights and image sensor". _2008 IEEE Radio and Wireless Symposium_. pp. 439–442. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/RWS.2008.4463523](https://doi.org/10.1109%2FRWS.2008.4463523). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-4244-1462-8](/wiki/Special:BookSources/978-1-4244-1462-8 "Special:BookSources/978-1-4244-1462-8"). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [1023383](https://api.semanticscholar.org/CorpusID:1023383) – via IEEE Xplore.
14. **[^](#cite_ref-14)**S. Horikawa, T. Komine, S. Haruyama and M. Nakagawa,”Pervasive Visible Light Positioning System using White LED Lighting”, IEICE, CAS2003-142, 2003.
15. **[^](#cite_ref-15)**Zhang, W.; Kavehrad, M. (2012). "A 2-D indoor localization system based on visible light LED". _2012 IEEE Photonics Society Summer Topical Meeting Series_. pp. 80–81. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/PHOSST.2012.6280711](https://doi.org/10.1109%2FPHOSST.2012.6280711). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-4577-1527-3](/wiki/Special:BookSources/978-1-4577-1527-3 "Special:BookSources/978-1-4577-1527-3"). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [10835473](https://api.semanticscholar.org/CorpusID:10835473).
16. **[^](#cite_ref-16)**Lee, Yong Up; Kavehrad, Mohsen (2012). "Long-range indoor hybrid localization system design with visible light communications and wireless network". _2012 IEEE Photonics Society Summer Topical Meeting Series_. pp. 82–83. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/PHOSST.2012.6280712](https://doi.org/10.1109%2FPHOSST.2012.6280712). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-4577-1527-3](/wiki/Special:BookSources/978-1-4577-1527-3 "Special:BookSources/978-1-4577-1527-3"). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [43879184](https://api.semanticscholar.org/CorpusID:43879184).
17. **[^](#cite_ref-17)**Panta, K.; Armstrong, J. (2012). "Indoor localisation using white LEDs". _Electronics Letters_. **48** (4): 228. [Bibcode](/wiki/Bibcode_(identifier) "Bibcode (identifier)"): [2012ElL....48..228P](https://ui.adsabs.harvard.edu/abs/2012ElL....48..228P). [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1049/el.2011.3759](https://doi.org/10.1049%2Fel.2011.3759).
18. **[^](#cite_ref-18)**Kim, Hyun-Seung; Kim, Deok-Rae; Yang, Se-Hoon; Son, Yong-Hwan; Han, Sang-Kook (2011). "Indoor positioning system based on carrier allocation visible light communication". _2011 International Quantum Electronics Conference (IQEC) and Conference on Lasers and Electro-Optics (CLEO) Pacific Rim incorporating the Australasian Conference on Optics, Lasers and Spectroscopy and the Australian Conference on Optical Fibre Technology_. pp. 787–789. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/IQEC-CLEO.2011.6193741](https://doi.org/10.1109%2FIQEC-CLEO.2011.6193741). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-0-9775657-8-8](/wiki/Special:BookSources/978-0-9775657-8-8 "Special:BookSources/978-0-9775657-8-8"). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [23878390](https://api.semanticscholar.org/CorpusID:23878390).
19. **[^](#cite_ref-19)**Giustiniano, Domenico; Tippenhauer, Nils Ole; Mangold, Stefan (2012). "Low-complexity Visible Light Networking with LED-to-LED communication". _2012 IFIP Wireless Days_. pp. 1–8. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/WD.2012.6402861](https://doi.org/10.1109%2FWD.2012.6402861). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-4673-4404-3](/wiki/Special:BookSources/978-1-4673-4404-3 "Special:BookSources/978-1-4673-4404-3"). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [14931354](https://api.semanticscholar.org/CorpusID:14931354).
20. **[^](#cite_ref-20)**Xin Huang; Bangdao Chen; A.W. Roscoe; "Multi−Channel Key Distribution Protocols Using Visible Light Communications in Body Sensor Networks", Computer Science Student Conference 2012, (pp. 15), Nov. 2012., [See publication here](http://www.cs.ox.ac.uk/conferences/OXFORD-CS-2012/proceedings2012.pdf#page=21)
21. **[^](#cite_ref-21)**Huang, X.; Guo, S.; Chen, B.; Roscoe, A. W. (2012). [_Bootstrapping body sensor networks using human controlled LED-camera channels_](https://ieeexplore.ieee.org/document/6470845). pp. 433–438. [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-4673-5325-0](/wiki/Special:BookSources/978-1-4673-5325-0 "Special:BookSources/978-1-4673-5325-0").
22. **[^](#cite_ref-22)**Haigh, Paul Anthony; Bausi, Francesco; Ghassemlooy, Zabih; Papakonstantinou, Ioannis; Le Minh, Hoa; Fléchon, Charlotte; Cacialli, Franco (2014). ["Visible light communications: Real time 10 Mb/S link with a low bandwidth polymer light-emitting diode"](https://eprint.ncl.ac.uk/fulltext.aspx?url=255660/DCDB4D6D-E57B-486F-840F-86FC46E0E69F.pdf&pub_id=255660). _Optics Express_. **22** (3): 2830–8. [Bibcode](/wiki/Bibcode_(identifier) "Bibcode (identifier)"): [2014OExpr..22.2830H](https://ui.adsabs.harvard.edu/abs/2014OExpr..22.2830H). [doi](/wiki/Doi_(identifier) "Doi (identifier)"):[10.1364/OE.22.002830](https://doi.org/10.1364%2FOE.22.002830). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [24663574](https://pubmed.ncbi.nlm.nih.gov/24663574).
23. **[^](#cite_ref-23)**Axrtek MOMO [Axrtek, Inc.](http://www.axrtek.com)
24. **[^](#cite_ref-24)**["Where are the discounts? Carrefour's LED supermarket lighting from Philips will guide you"](http://www.newscenter.philips.com/main/standard/news/press/2015/20150521-where-are-the-discounts-carrefours-led-supermarket-lighting-from-philips-will-guide-you.wpd#.VgAF-t-qpBc) (Press release). Philips. May 21, 2015.
25. **[^](#cite_ref-25)**Chen, Guojing (June 28, 2015). ["Commercial banks eye mobile payment innovations"](https://web.archive.org/web/20181003081412/http://en.ce.cn/Insight/201506/28/t20150628_5782240.shtml). _China Economic Net_. Archived from [the original](http://en.ce.cn/Insight/201506/28/t20150628_5782240.shtml) on October 3, 2018.
26. **[^](#cite_ref-26)**["Two more indoor positioning projects sprout in European supermarkets"](http://www.ledsmagazine.com/articles/2017/03/two-more-indoor-positioning-projects-sprout-in-european-supermarkets.html). _www.ledsmagazine.com_. 2017-03-08.
27. **[^](#cite_ref-27)**["Favendo collaborates with Philips Lighting"](http://www.favendo.com/wp-content/uploads/2017/02/06032017-Medieninformation-Favendo-Favendo_collaborates_with_Philips_Lighting.pdf)(PDF).
28. **[^](#cite_ref-28)**["Visible Light Communication"](http://www.ntu.edu.sg/home/ethanpng/). _www.ntu.edu.sg_. Retrieved 2015-12-24.
29. **[^](#cite_ref-29)**Bodrenko, A.I. (2018). ["New Wireless Technology Not Covered by the Existing IEEE Standards of 2017"](https://research-journal.org/technical/new-wireless-technology-not-covered-by-the-existing-ieee-standards-of-2017/). _International Research Journal_. **4** (70). [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.23670/IRJ.2018.70.022](https://doi.org/10.23670%2FIRJ.2018.70.022).
30. ^ [_**a**_](#cite_ref-:0_30-0) [_**b**_](#cite_ref-:0_30-1)Rodríguez, Juan; Lamar, Diego G.; Aller, Daniel G.; Miaja, Pablo F.; Sebastián, Javier (April 2018). ["Efficient Visible Light Communication Transmitters Based on Switching-Mode dc-dc Converters"](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5948605). _Sensors_. **18** (4): 1127. [Bibcode](/wiki/Bibcode_(identifier) "Bibcode (identifier)"): [2018Senso..18.1127R](https://ui.adsabs.harvard.edu/abs/2018Senso..18.1127R). [doi](/wiki/Doi_(identifier) "Doi (identifier)"):[10.3390/s18041127](https://doi.org/10.3390%2Fs18041127). [PMC](/wiki/PMC_(identifier) "PMC (identifier)") [5948605](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5948605). [PMID](/wiki/PMID_(identifier) "PMID (identifier)") [29642455](https://pubmed.ncbi.nlm.nih.gov/29642455).
31. **[^](#cite_ref-31)**Sebastian, Javier; Lamar, Diego G.; Aller, Daniel G.; Rodriguez, Juan; Miaja, Pablo F. (September 2018). ["On the Role of Power Electronics in Visible Light Communication"](https://ieeexplore.ieee.org/document/8351928). _IEEE Journal of Emerging and Selected Topics in Power Electronics_. **6** (3): 1210–1223. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/JESTPE.2018.2830878](https://doi.org/10.1109%2FJESTPE.2018.2830878). [hdl](/wiki/Hdl_(identifier) "Hdl (identifier)"):[10651/46845](https://hdl.handle.net/10651%2F46845). [ISSN](/wiki/ISSN_(identifier) "ISSN (identifier)") [2168-6777](https://search.worldcat.org/issn/2168-6777). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [19092607](https://api.semanticscholar.org/CorpusID:19092607).
32. **[^](#cite_ref-32)**Rodreguez, Juan; Lamar, Diego G.; Aller, Daniel G.; Miaja, Pablo F.; Sebastian, Javier (June 2018). ["Power-Efficient VLC Transmitter Able to Reproduce Multi-Carrier Modulation Schemes by Using the Output Voltage Ripple of the HB-LED Driver"](https://ieeexplore.ieee.org/document/8460175). _2018 IEEE 19th Workshop on Control and Modeling for Power Electronics (COMPEL)_. Padua: IEEE. pp. 1–8. [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/COMPEL.2018.8460175](https://doi.org/10.1109%2FCOMPEL.2018.8460175). [hdl](/wiki/Hdl_(identifier) "Hdl (identifier)"):[10651/48039](https://hdl.handle.net/10651%2F48039). [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [978-1-5386-5541-2](/wiki/Special:BookSources/978-1-5386-5541-2 "Special:BookSources/978-1-5386-5541-2"). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [52289901](https://api.semanticscholar.org/CorpusID:52289901).
33. **[^](#cite_ref-33)**Aziz, Amena Ejaz; Wong, Kainam Thomas; Chen, Jung-Chieh (2017). "Color-Shift Keying—How itItsargest Obtainable "Minimum Distance" Depends on its Preset Operating Chromaticity and Constellation Size". _Journal of Lightwave Technology_. **35** (13): 2724–2733. [Bibcode](/wiki/Bibcode_(identifier) "Bibcode (identifier)"): [2017JLwT...35.2724A](https://ui.adsabs.harvard.edu/abs/2017JLwT...35.2724A). [doi](/wiki/Doi_(identifier) "Doi (identifier)"): [10.1109/JLT.2017.2693363](https://doi.org/10.1109%2FJLT.2017.2693363). [hdl](/wiki/Hdl_(identifier) "Hdl (identifier)"):[10397/76267](https://hdl.handle.net/10397%2F76267). [S2CID](/wiki/S2CID_(identifier) "S2CID (identifier)") [13698944](https://api.semanticscholar.org/CorpusID:13698944).

## Further reading

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=12 "Edit section: Further reading")\]

- David G. Aviv (2006): Laser Space Communications, ARTECH HOUSE. [ISBN](/wiki/ISBN_(identifier) "ISBN (identifier)") [1-59693-028-4](/wiki/Special:BookSources/1-59693-028-4 "Special:BookSources/1-59693-028-4").

## External links

\[ [edit](/w/index.php?title=Visible_light_communication&action=edit&section=13 "Edit section: External links")\]

- IEEE [802.15 WPAN Task Group 7](http://www.ieee802.org/15/pub/TG7.html) (TG7) Visible Light Communication

- [v](/wiki/Template:Optical_telecommunication "Template:Optical telecommunication")
- [t](/wiki/Template_talk:Optical_telecommunication "Template talk:Optical telecommunication")
- [e](/wiki/Special:EditPage/Template:Optical_telecommunication "Special:EditPage/Template:Optical telecommunication")

[Optical telecommunication](/wiki/Optical_communication "Optical communication")

Basic

- [Smoke signal](/wiki/Smoke_signal "Smoke signal")
- [Beacon](/wiki/Beacon "Beacon")
- [Hydraulic telegraph](/wiki/Hydraulic_telegraph "Hydraulic telegraph")
- [Ships' flags](/wiki/International_maritime_signal_flags "International maritime signal flags")
- [Optical telegraph](/wiki/Optical_telegraph "Optical telegraph")
- [Heliograph](/wiki/Heliograph "Heliograph")
- [Signal lamp](/wiki/Signal_lamp "Signal lamp")
- [Photophone](/wiki/Photophone "Photophone")

Advanced

- [Fiber-optics](/wiki/Fiber-optic_communication "Fiber-optic communication")
  - [Optical fiber](/wiki/Optical_fiber "Optical fiber")
    - [Cable](/wiki/Fiber-optic_cable "Fiber-optic cable")
    - [Connectors](/wiki/Optical_fiber_connector "Optical fiber connector")
- [Optical wireless](/wiki/Optical_wireless_communications "Optical wireless communications")
  - [Free-space](/wiki/Free-space_optical_communication "Free-space optical communication")
  - Visible light
  - [Li-Fi](/wiki/Li-Fi "Li-Fi")
  - [In space](/wiki/Laser_communication_in_space "Laser communication in space")
  - [Consumer IR](/wiki/Consumer_IR "Consumer IR")
- [Optical Transport Network](/wiki/Optical_Transport_Network "Optical Transport Network")

Technologies

- [OC Rates](/wiki/Optical_Carrier_transmission_rates "Optical Carrier transmission rates")
- [Intensity modulation](/wiki/Intensity_modulation "Intensity modulation")
- [Modulating retro-reflector](/wiki/Modulating_retro-reflector "Modulating retro-reflector")

- ![](//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png)[Category](/wiki/Category:Optical_communications "Category:Optical communications")
- [![](//upload.wikimedia.org/wikipedia/en/thumb/e/e2/Symbol_portal_class.svg/16px-Symbol_portal_class.svg.png)](/wiki/File:Symbol_portal_class.svg "Portal")[Portal](/wiki/Portal:Telecommunication "Portal:Telecommunication")

- [v](/wiki/Template:Telecommunications "Template:Telecommunications")
- [t](/wiki/Template_talk:Telecommunications "Template talk:Telecommunications")
- [e](/wiki/Special:EditPage/Template:Telecommunications "Special:EditPage/Template:Telecommunications")

[Telecommunications](/wiki/Telecommunications "Telecommunications")

[History](/wiki/History_of_telecommunication "History of telecommunication")

- [Beacon](/wiki/Beacon#For_defensive_communications "Beacon")
- [Broadcasting](/wiki/History_of_broadcasting "History of broadcasting")
- [Cable protection system](/wiki/Cable_protection_system "Cable protection system")
- [Cable TV](/wiki/Cable_television "Cable television")
- [Communications satellite](/wiki/Communications_satellite#History "Communications satellite")
- [Computer network](/wiki/Computer_network#History "Computer network")
- [Data compression](/wiki/Data_compression "Data compression")
  - [audio](/wiki/Audio_coding_format "Audio coding format")
  - [DCT](/wiki/Discrete_cosine_transform "Discrete cosine transform")
  - [image](/wiki/Image_compression "Image compression")
  - [video](/wiki/Video_coding_format "Video coding format")
- [Digital media](/wiki/Digital_media "Digital media")
  - [Internet video](/wiki/Internet_video "Internet video")
  - [online video platform](/wiki/Online_video_platform "Online video platform")
  - [social media](/wiki/Social_media "Social media")
  - [streaming](/wiki/Streaming_media "Streaming media")
- [Drums](/wiki/Drums_in_communication "Drums in communication")
- [Edholm's law](/wiki/Edholm%27s_law "Edholm's law")
- [Electrical telegraph](/wiki/Electrical_telegraph#History "Electrical telegraph")
- [Fax](/wiki/Fax#History "Fax")
- [Heliographs](/wiki/Heliograph#History "Heliograph")
- [Hydraulic telegraph](/wiki/Hydraulic_telegraph#Greek_hydraulic_semaphore_system "Hydraulic telegraph")
- [Information Age](/wiki/Information_Age "Information Age")
- [Information revolution](/wiki/Information_revolution "Information revolution")
- [Internet](/wiki/History_of_the_Internet "History of the Internet")
- [Mass media](/wiki/Mass_media#History "Mass media")
- [Mobile phone](/wiki/History_of_mobile_phones "History of mobile phones")
  - [Smartphone](/wiki/Smartphone "Smartphone")
- [Optical telecommunication](/wiki/Optical_communication "Optical communication")
- [Optical telegraphy](/wiki/Optical_telegraph "Optical telegraph")
- [Pager](/wiki/Pager "Pager")
- [Photophone](/wiki/Photophone "Photophone")
- [Prepaid mobile phone](/wiki/History_of_prepaid_mobile_phones "History of prepaid mobile phones")
- [Radio](/wiki/History_of_radio "History of radio")
- [Radiotelephone](/wiki/Radiotelephone "Radiotelephone")
- [Satellite communications](/wiki/Communications_satellite "Communications satellite")
- [Semaphore](/wiki/Semaphore "Semaphore")
  - [Phryctoria](/wiki/Phryctoria "Phryctoria")
- [Semiconductor](/wiki/Semiconductor "Semiconductor")
  - [device](/wiki/Semiconductor_device "Semiconductor device")
  - [MOSFET](/wiki/MOSFET "MOSFET")
  - [transistor](/wiki/History_of_the_transistor "History of the transistor")
- [Smoke signals](/wiki/Smoke_signal "Smoke signal")
- [Telecommunications history](/wiki/History_of_telecommunication "History of telecommunication")
- [Telautograph](/wiki/Telautograph "Telautograph")
- [Telegraphy](/wiki/Telegraphy "Telegraphy")
- [Teleprinter](/wiki/Teleprinter "Teleprinter") (teletype)
- [Telephone](/wiki/History_of_the_telephone "History of the telephone")
- _[The Telephone Cases](/wiki/The_Telephone_Cases "The Telephone Cases")_
- [Television](/wiki/History_of_television "History of television")
  - [digital](/wiki/Digital_television "Digital television")
  - [streaming](/wiki/Streaming_television "Streaming television")
- [Undersea telegraph line](/wiki/Submarine_communications_cable#Early_history:_telegraph_and_coaxial_cables "Submarine communications cable")
- [Videotelephony](/wiki/History_of_videotelephony "History of videotelephony")
- [Whistled language](/wiki/Whistled_language "Whistled language")
- [Wireless revolution](/wiki/Wireless_revolution "Wireless revolution")

Pioneers

- [Nasir Ahmed](/wiki/Nasir_Ahmed_(engineer) "Nasir Ahmed (engineer)")
- [Edwin Howard Armstrong](/wiki/Edwin_Howard_Armstrong "Edwin Howard Armstrong")
- [Mohamed M. Atalla](/wiki/Mohamed_M._Atalla "Mohamed M. Atalla")
- [John Logie Baird](/wiki/John_Logie_Baird "John Logie Baird")
- [Paul Baran](/wiki/Paul_Baran "Paul Baran")
- [John Bardeen](/wiki/John_Bardeen "John Bardeen")
- [Alexander Graham Bell](/wiki/Alexander_Graham_Bell "Alexander Graham Bell")
- [Emile Berliner](/wiki/Emile_Berliner "Emile Berliner")
- [Tim Berners-Lee](/wiki/Tim_Berners-Lee "Tim Berners-Lee")
- [Francis Blake (telephone)](/wiki/Francis_Blake_(telephone) "Francis Blake (telephone)")
- [Jagadish Chandra Bose](/wiki/Jagadish_Chandra_Bose "Jagadish Chandra Bose")
- [Charles Bourseul](/wiki/Charles_Bourseul "Charles Bourseul")
- [Walter Houser Brattain](/wiki/Walter_Houser_Brattain "Walter Houser Brattain")
- [Vint Cerf](/wiki/Vint_Cerf "Vint Cerf")
- [Claude Chappe](/wiki/Claude_Chappe "Claude Chappe")
- [Yogen Dalal](/wiki/Yogen_Dalal "Yogen Dalal")
- [Daniel Davis Jr.](/wiki/Daniel_Davis_Jr. "Daniel Davis Jr.")
- [Donald Davies](/wiki/Donald_Davies "Donald Davies")
- [Amos Dolbear](/wiki/Amos_Dolbear "Amos Dolbear")
- [Thomas Edison](/wiki/Thomas_Edison "Thomas Edison")
- [Lee de Forest](/wiki/Lee_de_Forest "Lee de Forest")
- [Philo Farnsworth](/wiki/Philo_Farnsworth "Philo Farnsworth")
- [Reginald Fessenden](/wiki/Reginald_Fessenden "Reginald Fessenden")
- [Elisha Gray](/wiki/Elisha_Gray "Elisha Gray")
- [Oliver Heaviside](/wiki/Oliver_Heaviside "Oliver Heaviside")
- [Robert Hooke](/wiki/Robert_Hooke "Robert Hooke")
- [Erna Schneider Hoover](/wiki/Erna_Schneider_Hoover "Erna Schneider Hoover")
- [Harold Hopkins](/wiki/Harold_Hopkins_(physicist) "Harold Hopkins (physicist)")
- [Gardiner Greene Hubbard](/wiki/Gardiner_Greene_Hubbard "Gardiner Greene Hubbard")
- [Internet pioneers](/wiki/List_of_Internet_pioneers "List of Internet pioneers")
- [Bob Kahn](/wiki/Bob_Kahn "Bob Kahn")
- [Dawon Kahng](/wiki/Dawon_Kahng "Dawon Kahng")
- [Charles K. Kao](/wiki/Charles_K._Kao "Charles K. Kao")
- [Narinder Singh Kapany](/wiki/Narinder_Singh_Kapany "Narinder Singh Kapany")
- [Hedy Lamarr](/wiki/Hedy_Lamarr "Hedy Lamarr")
- [Innocenzo Manzetti](/wiki/Innocenzo_Manzetti "Innocenzo Manzetti")
- [Guglielmo Marconi](/wiki/Guglielmo_Marconi "Guglielmo Marconi")
- [Robert Metcalfe](/wiki/Robert_Metcalfe "Robert Metcalfe")
- [Antonio Meucci](/wiki/Antonio_Meucci "Antonio Meucci")
- [Samuel Morse](/wiki/Samuel_Morse "Samuel Morse")
- [Jun-ichi Nishizawa](/wiki/Jun-ichi_Nishizawa "Jun-ichi Nishizawa")
- [Charles Grafton Page](/wiki/Charles_Grafton_Page "Charles Grafton Page")
- [Radia Perlman](/wiki/Radia_Perlman "Radia Perlman")
- [Alexander Stepanovich Popov](/wiki/Alexander_Stepanovich_Popov "Alexander Stepanovich Popov")
- [Tivadar Puskás](/wiki/Tivadar_Pusk%C3%A1s "Tivadar Puskás")
- [Johann Philipp Reis](/wiki/Johann_Philipp_Reis "Johann Philipp Reis")
- [Claude Shannon](/wiki/Claude_Shannon "Claude Shannon")
- [Almon Brown Strowger](/wiki/Almon_Brown_Strowger "Almon Brown Strowger")
- [Henry Sutton](/wiki/Henry_Sutton_(inventor) "Henry Sutton (inventor)")
- [Charles Sumner Tainter](/wiki/Charles_Sumner_Tainter "Charles Sumner Tainter")
- [Nikola Tesla](/wiki/Nikola_Tesla "Nikola Tesla")
- [Camille Tissot](/wiki/Camille_Tissot "Camille Tissot")
- [Alfred Vail](/wiki/Alfred_Vail "Alfred Vail")
- [Thomas A. Watson](/wiki/Thomas_A._Watson "Thomas A. Watson")
- [Charles Wheatstone](/wiki/Charles_Wheatstone "Charles Wheatstone")
- [Vladimir K. Zworykin](/wiki/Vladimir_K._Zworykin "Vladimir K. Zworykin")

[Transmission\
\
media](/wiki/Transmission_medium "Transmission medium")

- [Coaxial cable](/wiki/Coaxial_cable "Coaxial cable")
- [Fiber-optic communication](/wiki/Fiber-optic_communication "Fiber-optic communication")
  - [optical fiber](/wiki/Optical_fiber "Optical fiber")
- [Free-space optical communication](/wiki/Free-space_optical_communication "Free-space optical communication")
- [Molecular communication](/wiki/Molecular_communication "Molecular communication")
- [Radio waves](/wiki/Radio_wave "Radio wave")
  - [wireless](/wiki/Wireless "Wireless")
- [Transmission line](/wiki/Transmission_line "Transmission line")
  - [telecommunication circuit](/wiki/Telecommunication_circuit "Telecommunication circuit")

[Network topology](/wiki/Network_topology "Network topology")

and switching

- [Bandwidth](/wiki/Bandwidth_(computing) "Bandwidth (computing)")
- [Links](/wiki/Telecommunications_link "Telecommunications link")
- [Nodes](/wiki/Node_(networking) "Node (networking)")
  - [terminal](/wiki/Terminal_(telecommunication) "Terminal (telecommunication)")
- [Network switching](/wiki/Network_switch "Network switch")
  - [circuit](/wiki/Circuit_switching "Circuit switching")
  - [packet](/wiki/Packet_switching "Packet switching")
- [Telephone exchange](/wiki/Telephone_exchange "Telephone exchange")

[Multiplexing](/wiki/Multiplexing "Multiplexing")

- [Space-division](/wiki/Space-division_multiple_access "Space-division multiple access")
- [Frequency-division](/wiki/Frequency-division_multiplexing "Frequency-division multiplexing")
- [Time-division](/wiki/Time-division_multiplexing "Time-division multiplexing")
- [Polarization-division](/wiki/Polarization-division_multiplexing "Polarization-division multiplexing")
- [Orbital angular-momentum](/wiki/Orbital_angular_momentum_multiplexing "Orbital angular momentum multiplexing")
- [Code-division](/wiki/Code-division_multiple_access "Code-division multiple access")

Concepts

- [Communication protocol](/wiki/Communication_protocol "Communication protocol")
- [Computer network](/wiki/Computer_network "Computer network")
- [Data transmission](/wiki/Data_communication "Data communication")
- [Store and forward](/wiki/Store_and_forward "Store and forward")
- [Telecommunications equipment](/wiki/Telecommunications_equipment "Telecommunications equipment")

[Types of network](/wiki/Telecommunications_network "Telecommunications network")

- [Cellular network](/wiki/Cellular_network "Cellular network")
- [Ethernet](/wiki/Ethernet "Ethernet")
- [ISDN](/wiki/Integrated_Services_Digital_Network "Integrated Services Digital Network")
- [LAN](/wiki/Local_area_network "Local area network")
- [Mobile](/wiki/Mobile_telephony "Mobile telephony")
- [NGN](/wiki/Next-generation_network "Next-generation network")
- [Public Switched Telephone](/wiki/Public_switched_telephone_network "Public switched telephone network")
- [Radio](/wiki/Radio_network "Radio network")
- [Television](/wiki/Television_broadcasting "Television broadcasting")
- [Telex](/wiki/Telex "Telex")
- [UUCP](/wiki/UUCP "UUCP")
- [WAN](/wiki/Wide_area_network "Wide area network")
- [Wireless network](/wiki/Wireless_network "Wireless network")

[Notable networks](/wiki/Telecommunications_network "Telecommunications network")

- [ARPANET](/wiki/ARPANET "ARPANET")
- [BITNET](/wiki/BITNET "BITNET")
- [CYCLADES](/wiki/CYCLADES "CYCLADES")
- [FidoNet](/wiki/FidoNet "FidoNet")
- [Internet](/wiki/Internet "Internet")
- [Internet2](/wiki/Internet2 "Internet2")
- [JANET](/wiki/JANET "JANET")
- [NPL network](/wiki/NPL_network "NPL network")
- [Toasternet](/wiki/Toasternet "Toasternet")
- [Usenet](/wiki/Usenet "Usenet")

Locations

- [Africa](/wiki/Category:Telecommunications_in_Africa "Category:Telecommunications in Africa")
- Americas
  - [North](/wiki/Category:Telecommunications_in_North_America "Category:Telecommunications in North America")
  - [South](/wiki/Category:Telecommunications_in_South_America "Category:Telecommunications in South America")
- [Antarctica](/wiki/Category:Communications_in_Antarctica "Category:Communications in Antarctica")
- [Asia](/wiki/Category:Telecommunications_in_Asia "Category:Telecommunications in Asia")
- [Europe](/wiki/Category:Telecommunications_in_Europe "Category:Telecommunications in Europe")
- [Oceania](/wiki/Category:Telecommunications_in_Oceania "Category:Telecommunications in Oceania")
- ( [Global telecommunications regulation bodies](/wiki/List_of_telecommunications_regulatory_bodies "List of telecommunications regulatory bodies"))

- ![](//upload.wikimedia.org/wikipedia/commons/thumb/4/4e/Telecom-icon.svg/16px-Telecom-icon.svg.png)[Telecommunication portal](/wiki/Portal:Telecommunication "Portal:Telecommunication")
- ![](//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png)[Category](/wiki/Category:Telecommunications "Category:Telecommunications")
- ![](//upload.wikimedia.org/wikipedia/en/thumb/d/db/Symbol_list_class.svg/16px-Symbol_list_class.svg.png)[Outline](/wiki/Outline_of_telecommunication "Outline of telecommunication")
- ![](//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png)[Commons](https://commons.wikimedia.org/wiki/Category:Telecommunications "commons:Category:Telecommunications")

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[Categories](/wiki/Help:Category "Help:Category"):

- [Optical communications](/wiki/Category:Optical_communications "Category:Optical communications")
- [Telecommunications](/wiki/Category:Telecommunications "Category:Telecommunications")
- [Light](/wiki/Category:Light "Category:Light")

Hidden categories:

- [All articles with dead external links](/wiki/Category:All_articles_with_dead_external_links "Category:All articles with dead external links")
- [Articles with dead external links from May 2011](/wiki/Category:Articles_with_dead_external_links_from_May_2011 "Category:Articles with dead external links from May 2011")
- [Webarchive template wayback links](/wiki/Category:Webarchive_template_wayback_links "Category:Webarchive template wayback links")
- [Articles with short description](/wiki/Category:Articles_with_short_description "Category:Articles with short description")
- [Short description is different from Wikidata](/wiki/Category:Short_description_is_different_from_Wikidata "Category:Short description is different from Wikidata")

- This page was last edited on 26 June 2024, at 07:28 (UTC).
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