67:. The cable is "leaky" in that it has gaps or slots in its outer conductor to allow the radio signal to leak into or out of the cable along its entire length. Because of this leakage of signal, line amplifiers are required to be inserted at regular intervals, typically every 350 to 500 metres, to boost the signal back up to acceptable levels. The signal is usually picked up by portable transceivers carried by personnel. Transmissions from the transceivers are picked up by the feeder and carried to other parts of the tunnel, allowing
20:
163:, where it hampered rescue efforts. In March 2020, two additional leaky feeder cables were brought online in the Jubilee line tunnels between Canning Town and Westminster. One of these cables provided commercial 4G coverage for passengers, both in the tunnels and on station platforms, whilst the second cable provided coverage for the Home Office's
170:
Tyne and Wear Metro was the first railway in the UK to use leaky feeder cables for public mobile phone connectivity, in its city-centre underground tunnels. Initially this was a 2G signal, but then mobile operator EE upgraded this to 4G for their customers. As of 2023, operator Nexus are planning a
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on passenger aircraft. The weight and space requirements of leaky feeder systems are usually lower than comparable antenna systems, thus saving space and fuel. The even field strengths produced by runs of leaky feeders spanning the entire fuselage improve coverage while requiring less transmitting
107:
Leaky feeders are used in the mining industry as a method of wireless communication between miners. The system is used as a primary communication system which has a transceiver small enough to be comfortably worn on a miner throughout an entire shift.
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Due to the signal loss along the feeder, a leaky feeder is usually used for frequencies under 1 GHz. Above that frequency the losses require too many repeaters, thus making other options more effective. Antennae (omni, panel or bi-directional) or even
167:(ESN), which is currently being rolled out to replace the ageing Airwave network. This trial section is the first to be brought online as part of a project to provide both commercial 4G coverage and ESN coverage across the entire Tube network.
139:), leaky feeders were incorporated in the specification of the capital project and installed during construction. This gives emergency services seamless mobile communication from the underground to the surface.
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Leaky feeders are used in hotels, warehouses and other industrial buildings where it is difficult to get Wi‑Fi coverage using normal
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43:" as this implies that the cable is designed to radiate: something that coaxial cable is not generally supposed to do.
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155:, was not compatible and did not work below ground. The fact that this situation continued to exist after the 1987
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IWT Wireless
Communications and Tracking in Underground Mines - a wireless mesh alternative to leaky feeder
215:. Some installations have 50–75 meters of leaky wire connected to the antenna output of each access point.
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https://www.nexus.org.uk/news/item/nexus-announces-plan-improve-digital-connectivity-tyne-and-wear-metro
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Leaky feeder antenna system can also be used to allow use of on-board cellular phones and
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377:"Basic Tutorial on Wireless Communication and Electronic Tracking: Technology Overview"
680:"A Resonator Enhanced UHF RFID Antenna Cable for Inventory and Warehouse Applications"
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and other tunnel environments. Manufacturers and cabling professionals use the term "
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The system has a limited range and because of the frequency it uses (typically
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Putaala, Jussi; Myllymäki, Sami; Kokkonen, Mikko; Jantunen, Heli (July 2021).
82:), transmissions cannot pass through solid rock, which limits the system to a
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Kokkonen, Mikko; Myllymaki, Sami; Putaala, Jussi; Jantunen, Heli (2022).
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comprehensive upgrade to mobile data coverage, including in the tunnels.
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The leaky feeder system is used for underground mobile communication in
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Communications system used in underground mining and tunnel environments
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An alternative to using leaky feeder in underground railways is to use
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application. It does, however, allow two-way mobile communication.
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uses a leaky feeder system for its internal communication network
611:"Leaky Feeder Communication and Installation Guide for Business"
473:"Inside the messy mission to bring 4G to the London Underground"
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A leaky feeder modified with metallic strips can be used as a
151:. However, the communication used by the emergency services,
638:"Resonator-enhanced radiating cable for UHF RFID readers"
572:
ETSI White Paper No. 4 GSM operation onboard aircraft
447:"4G on Jubilee line tunnel section from March 2020"
190:and mobile phone and data coverage for customers.
262:"Improvements coming soon to mine communications"
94:are more often used for higher frequency bands.
425:"Communications blamed in London bomb response"
684:IEEE Journal of Radio Frequency Identification
8:
379:. Centers for Disease Control and Prevention
71:communication throughout the tunnel system.
294:"Times Microwave Radiating Cable Catalogue"
59:run along tunnels which emits and receives
594:"Leaky Feeder Antennas for Airborne Wi-Fi"
703:
541:"Tunnel vision: getting New York talking"
178:(DAS). A DAS system was deployed in some
645:Microwave and Optical Technology Letters
18:
253:
159:was criticised in the reports from the
505:"Emergency Services Network: overview"
399:"Victoria line heads Metronet renewal"
539:Nally, Jonathan (30 September 2013).
242:Through the earth mine communications
7:
129:rail transport systems of Hong Kong
55:communication system consists of a
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427:. PC Advisor. 23 February 2012
225:radio-frequency identification
1:
403:Railway Gazette International
63:, functioning as an extended
23:Diagram of leaky feeder cable
471:Kobie, Nicole (2020-02-05).
615:Wall to Wall Communications
590:W. L. Gore & Associates
194:In-flight wireless networks
161:7 July 2005 London bombings
92:distributed antenna systems
762:
705:10.1109/jrfid.2021.3135047
347:"Radiating cable revealed"
176:Distributed Antenna System
165:Emergency Services Network
351:Radio Frequency Systems
24:
22:
451:Transport for London
207:Industrial buildings
180:New York City Subway
112:Underground railways
696:2022IJRFI...6..128K
592:(15 October 2013),
617:. 11 February 2019
274:. 19 February 2007
237:Tunnel transmitter
143:London Underground
37:underground mining
25:
657:10.1002/mop.32844
598:Microwave Journal
551:on 1 October 2013
357:on 30 August 2017
322:"Radiating Cable"
157:King's Cross fire
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619:. Retrieved
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361:13 September
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182:stations by
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118:mass transit
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98:Applications
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53:leaky feeder
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29:leaky feeder
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186:to provide
125:Delhi Metro
61:radio waves
514:2021-03-12
490:2021-03-12
457:2021-03-12
248:References
137:CityRingen
131:, and the
714:245218056
665:233392835
485:1357-0978
326:CommScope
135:(Danish:
123:. In the
47:Principle
746:Antennas
740:Category
621:12 March
477:Wired UK
306:12 March
231:See also
121:railways
692:Bibcode
555:8 March
431:6 March
409:6 March
383:8 March
278:6 March
203:power.
153:Airwave
148:Connect
65:antenna
712:
663:
509:GOV.UK
483:
103:Mining
710:S2CID
661:S2CID
641:(PDF)
576:(PDF)
297:(PDF)
200:Wi‑Fi
188:Wi‑Fi
57:cable
31:is a
623:2019
557:2014
481:ISSN
433:2012
411:2012
385:2014
363:2014
333:2014
308:2017
280:2012
219:RFID
700:doi
653:doi
80:UHF
78:or
76:VHF
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
