8 ms·

Manhole Covers Serve as Antennas Expanding Wireless Network Coverage

125 points by Varcht 8y ago

kenzoid 8y ago
That's pretty clever, and appears to be already in use even for 4G.
- abbe_k 8y ago
  Yes, I know Swisscom does this already.
  - PappaPatat 8y ago
    For a little background [0]: "Swisscom and Ericsson have proved that city manholes can be used worldwide to improve capacity with small cells – even below street level – using the Ericsson Vault Remote Radio Unit and Kathrein’s Street Connect, an in-ground microcell antenna system. The use of existing street manholes where fiber and power already exists lowers total cost of ownership by 50 percent. This, the world’s first vault site for LTE and small cells has been approved by the Swiss authorities, and 250 new rollouts are due during 2016 in the country’s cities. The solution effectively addresses cities’ needs by enabling the reuse of existing assets and underground space." Really since 2016. Good framing by Voda to present this as "Building on its heritage of innovation". [0] https://www.ericsson.com/en/news/2016/3/swisscom-and-ericsson-plant-lte-small-cells-underground https://www.ericsson.com/en/news/2016/3/swisscom-and-ericsso... [1] https://ieeexplore.ieee.org/document/7481351 https://ieeexplore.ieee.org/document/7481351
mevile 8y ago
I'm curious how this affects the NIMBY fights about antennas. Some of those fights are about aesthetics of the antennas, but some of the concern is around the radiation, which is not a finished debate. Mobile phone signals have been designated as possibly a cause of cancer by the WHO if I recall correctly. It hasn't been possible to rule out that mobile phones do not cause harm, which is something I was surprised to learn. I thought it was a settled debate that mobile phones were safe. https://www.cancer.gov/about-cancer/causes-prevention/risk/radiation/cell-phones-fact-sheet https://www.cancer.gov/about-cancer/causes-prevention/risk/r...
- JumpCrisscross 8y ago
  > phone signals have been designated as possibly a cause of cancer by the WHO No, it has not. "To date, research does not suggest any consistent evidence of adverse health effects from exposure to radiofrequency fields at levels below those that cause tissue heating" [1]. [1] https://www.who.int/news-room/fact-sheets/detail/electromagnetic-fields-and-public-health-mobile-phones https://www.who.int/news-room/fact-sheets/detail/electromagn...
  - flatline 8y ago
    And yet the second bullet in that article: > The electromagnetic fields produced by mobile phones are classified by the International Agency for Research on Cancer as possibly carcinogenic to humans. So it's not settled science, even though there is some evidence pointing toward it not causing cancer.
    - steve19 8y ago
      There is a lot of evidence, long term studies, showing they do not do cancer. So the question is why are they listed as a possible cause? It invalidates the entire list. My car keys may well "possibly" cause cancer if the bar is so low.
      - JonathonW 8y ago
        The specific item that is on the IARC Group 2B ("possibly carcinogenic") is "radiofrequency electromagnetic fields", which includes exposures due to cell phone use-- cell phone radiation specifically is not classified. So, if your car has keyless entry, your car keys would technically also be on the list.
    - wbl 8y ago
      What has IARC excluded from causing cancer?
    - kevhito 8y ago
      From wikipedia, it says "limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals. It may also be used when there is inadequate evidence of carcinogenicity in humans but there is sufficient evidence of carcinogenicity in experimental animals. In some instances, an agent, mixture or exposure circumstance for which there is inadequate evidence of carcinogenicity in humans but limited evidence of carcinogenicity in experimental animals together with supporting evidence from other relevant data may be placed in this group." Anecdotally, I see alongside some unpleasant-sounding items, a lot of common things on that same list like: aloe vera, Ginkgo biloba, engine exhaust, pickled vegetables, and cocamide DEA. It seems to me that mere presence on that list doesn't mean much without further context -- why it was put on the list, the relative danger of it compared to other things on that list, etc.
sandworm101 8y ago
Are these proper manhole covers? I mean the big heavy metal type that can support vehicle traffic? The one in the picture seems the type for covering access to a "manhole" but not one under a street. I do have to wonder whether the local cell will drop out every time a huge metal object, a bus, rolls over the cover. >>It eliminates traffic disruptions from street construction, and there are no antennas awkwardly placed on buildings, marring the appearance of a neighborhood. Said by someone who has never attempted to install anything inside a manhole. They will need to close the streets. You cannot just creep through the sewers installing stuff without disrupting the traffic above. Workers are not moles. They will need to run new lines. And in modern cities, the type without the huge walk-in storm sewers of NY/London/Paris/SF, there will still be digging. With many innovations these days it is hard to determine feasibility from initial articles/claims. Lots of inventions seem to exist only to get grant money, with no hope of practicality (solar roads, solar windows). If these are lightweight manhole covers that cannot support traffic (ie just an antenna mounted atop an aluminum cover) then I'll chalk it up alongside those sidewalk tiles that generate electricity from pedestrians: might work, but will never be practical. https://en.wikipedia.org/wiki/Solar_Roadways https://en.wikipedia.org/wiki/Solar_Roadways https://www.6sqft.com/pavegen-opens-worlds-first-smart-street-which-generates-electricity-from-footsteps/ https://www.6sqft.com/pavegen-opens-worlds-first-smart-stree...
- deleted 8y ago
  [deleted]
- twic 8y ago
  I don't think London has huge walk-in storm sewers. And there are certainly people digging up everything they can see, all the time, at least on the roads i use to get to work.
  - deleted 8y ago
    [deleted]
  - sandworm101 8y ago
    It does. The old cities have combined systems, storm and sewage together. To accommodate rainwater and maintenance, they are essentially brick corridors. Some are huge. https://www.telegraph.co.uk/sponsored/why-not/11621489/sewer-tours-in-london-and-brighton.html https://www.telegraph.co.uk/sponsored/why-not/11621489/sewer... More modern cities have separate systems for sewage and stormwater, and these are contained in small pipes that people cannot walk around in. Upgrading from a combined system is a massive project, well beyond something like 5g imho. https://www.thames21.org.uk/combined-sewer-systems/ https://www.thames21.org.uk/combined-sewer-systems/
shanghaiaway 8y ago
Wow, that must be why I start itching whenever I pass a manhole cover.
lifeisstillgood 8y ago
A side issue with 5G is that there are all sorts of fun / unusual effects being discovered with GSM/wifi suffusing our environments - i remember Stanford being able to detect people moving behind a wall using the wifi signals. Simply Monitoring signal strength has had many commercial opportunities and now we are going to put millimetre wave radar throughout our cities - expect novel uses to crop up
cypherpunks01 8y ago
Wouldn't traffic poles serve as better publicly-owned antenna mount points? They are powered and have better line of sight to everything (broader range). I wonder why manholes are considered better.
- ajdhsjakafjt 8y ago
  The article doesn't state it was better than traffic lights. I think small cells in traffic lights are already reality, even if not widespread, the small cells exist. The article presents a novel, non-obvious approach in some ealier-stage development.
- ldite 8y ago
  As I understand it, they're owned by different entities; the street lights/traffic poles are often owned by local authorities (in the UK) while manhole covers are owner by the utilities. I suspect that one aspect of this is to give them leverage in getting access to antenna sites.
chatterbeak 8y ago
_Person_ hole covers.
lykr0n 8y ago
The more I hear about 5G, the more I think it's an industry trying to sell a product that nobody is asking for. I have no complaints about the speed I get on my iPhone from T-Mobile here in the US. I wish I had better LTE coverage, but I'm happy with the performance. Most of the time it's snappier than my Wi-Fi (which is weird). I get a solid 8 to 20 mbits under fair conditions- I can stream movies and music just fine. All I hear about 5G is that it requires a large amount of antennas on both your phone (4 because a hand covering the antenna can cause a drop in signal) and around you. I don't want to be near a high power transmitter that's low frequency, and I really don't want to be near a high frequency one. What's the sell of 5G? I guess the speed, but what? 1 Gbit to my phone? Why. Considering that I only get 15GB of "Unlimited" data now, it isn't going to replace Wi-F. Because of the density required of the towers, it's not going to replace 4G/LTE as some areas it's just unrealistic to have the required density.
- acchow 8y ago
  You're still thinking in 2018 terms. What about 2025?
- LeoPanthera 8y ago
  640K ought to be enough for anybody.
- awakeasleep 8y ago
  Bandwidth is tremendously important in wireless communications because the more data you can transmit in less time, the less time you need to be transmitting. In general, only one radio can transmit on one frequency at a time. So a city wide network quickly becomes congested. Reducing the time everyone spends transmitting greatly increases the quality of service and the amount of users that can be serviced. The increased antenna count is also a benefit in crowded situations. If each antenna covers a smaller range, then more people can use the network in a given area- two antennas that would interfere with each other in a longer range system will operate simultaneously.
  - lykr0n 8y ago
    They've solved that issue by deploying more towers in high density areas and carriers have swapped allocations in areas to get more continuous spectrum. Upping the frequency just gives you wider bands. I think a better argument could be made about spending R&D on making 4G/LTE require a smaller band. I think LTE (assuming 850MHz) can be 1.4, 3, 5, 10MHz per band- which is non-optional. If you could cut the required Tx/Rx band width in half; I think that would be better use of effort.
bjt2n3904 8y ago
When I was in college, I remember taking a class in silicon design. At one point, a student remarked, "man, silicon is like... black magic." "No," the teacher sharply rebuked. "It's governed by well understood and reliable mathematical equations. Though difficult, it is far from magic." There was a brief pause, the teacher was normally easy going and congenial. His harsh words caught us off guard. "...antennas on the other hand, that is black magic."
- andreareina 8y ago
  Indistinguishable From Magic: Manufacturing Modern Computer Chips -- https://www.youtube.com/watch?v=NGFhc8R_uO4 https://www.youtube.com/watch?v=NGFhc8R_uO4
  - Joona 8y ago
    Same talk (slightly updated perhaps?) in higher quality: https://www.youtube.com/watch?v=KL-I3-C-KBk https://www.youtube.com/watch?v=KL-I3-C-KBk
    - andreareina 8y ago
      Didn't know about that, thanks!
liotier 8y ago
This means we may have to run power supplies to existing fiber manholes...
Uberphallus 8y ago
I'm far from an expert, but aren't manholes (and streetlights and traffic lights, by extension) effectively grounded, hence incurring into insane loss?
- posterboy 8y ago
  Came here to wonder the same. Do they wind a coil around it?
- Johnythree 8y ago
  Many Antennas are grounded (eg for lightning protection), but that has no relevance for their effectiveness as an antenna. Because the size is much less than a wavelength, the body can be at ground, while the active parts can be at RF potential. Example: Your phone is grounded, but it still works.
  - Uberphallus 8y ago
    They are grounded with a precise length of coax (multiples of 1/4 or 1/2 wave, IIRC) to keep the VSWR ratio low for the intended frequency. In a pole you can get to do that by probing the signal at certain height, but the active part of a patch antenna (which I assume a manhole works as) is at the extremes of it (as such, probes are always off center for circular polarization, and at the extreme for linear), and those are grounded. Patch antennas are normally grounded at the center, as the voltage/current there should be close enough to 0 anyway unless there's an electrostatic discharge.

125 points by Varcht 8y ago

kenzoid 8y ago

That's pretty clever, and appears to be already in use even for 4G.

abbe_k 8y ago
Yes, I know Swisscom does this already.
- PappaPatat 8y ago
  For a little background [0]: "Swisscom and Ericsson have proved that city manholes can be used worldwide to improve capacity with small cells – even below street level – using the Ericsson Vault Remote Radio Unit and Kathrein’s Street Connect, an in-ground microcell antenna system. The use of existing street manholes where fiber and power already exists lowers total cost of ownership by 50 percent. This, the world’s first vault site for LTE and small cells has been approved by the Swiss authorities, and 250 new rollouts are due during 2016 in the country’s cities. The solution effectively addresses cities’ needs by enabling the reuse of existing assets and underground space." Really since 2016. Good framing by Voda to present this as "Building on its heritage of innovation". [0] https://www.ericsson.com/en/news/2016/3/swisscom-and-ericsson-plant-lte-small-cells-underground https://www.ericsson.com/en/news/2016/3/swisscom-and-ericsso... [1] https://ieeexplore.ieee.org/document/7481351 https://ieeexplore.ieee.org/document/7481351

mevile 8y ago

I'm curious how this affects the NIMBY fights about antennas. Some of those fights are about aesthetics of the antennas, but some of the concern is around the radiation, which is not a finished debate. Mobile phone signals have been designated as possibly a cause of cancer by the WHO if I recall correctly. It hasn't been possible to rule out that mobile phones do not cause harm, which is something I was surprised to learn. I thought it was a settled debate that mobile phones were safe. https://www.cancer.gov/about-cancer/causes-prevention/risk/radiation/cell-phones-fact-sheet https://www.cancer.gov/about-cancer/causes-prevention/risk/r...

JumpCrisscross 8y ago
> phone signals have been designated as possibly a cause of cancer by the WHO No, it has not. "To date, research does not suggest any consistent evidence of adverse health effects from exposure to radiofrequency fields at levels below those that cause tissue heating" [1]. [1] https://www.who.int/news-room/fact-sheets/detail/electromagnetic-fields-and-public-health-mobile-phones https://www.who.int/news-room/fact-sheets/detail/electromagn...
- flatline 8y ago
  And yet the second bullet in that article: > The electromagnetic fields produced by mobile phones are classified by the International Agency for Research on Cancer as possibly carcinogenic to humans. So it's not settled science, even though there is some evidence pointing toward it not causing cancer.
  - steve19 8y ago
    There is a lot of evidence, long term studies, showing they do not do cancer. So the question is why are they listed as a possible cause? It invalidates the entire list. My car keys may well "possibly" cause cancer if the bar is so low.
    - JonathonW 8y ago
      The specific item that is on the IARC Group 2B ("possibly carcinogenic") is "radiofrequency electromagnetic fields", which includes exposures due to cell phone use-- cell phone radiation specifically is not classified. So, if your car has keyless entry, your car keys would technically also be on the list.
  - wbl 8y ago
    What has IARC excluded from causing cancer?
  - kevhito 8y ago
    From wikipedia, it says "limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals. It may also be used when there is inadequate evidence of carcinogenicity in humans but there is sufficient evidence of carcinogenicity in experimental animals. In some instances, an agent, mixture or exposure circumstance for which there is inadequate evidence of carcinogenicity in humans but limited evidence of carcinogenicity in experimental animals together with supporting evidence from other relevant data may be placed in this group." Anecdotally, I see alongside some unpleasant-sounding items, a lot of common things on that same list like: aloe vera, Ginkgo biloba, engine exhaust, pickled vegetables, and cocamide DEA. It seems to me that mere presence on that list doesn't mean much without further context -- why it was put on the list, the relative danger of it compared to other things on that list, etc.

sandworm101 8y ago

Are these proper manhole covers? I mean the big heavy metal type that can support vehicle traffic? The one in the picture seems the type for covering access to a "manhole" but not one under a street. I do have to wonder whether the local cell will drop out every time a huge metal object, a bus, rolls over the cover. >>It eliminates traffic disruptions from street construction, and there are no antennas awkwardly placed on buildings, marring the appearance of a neighborhood. Said by someone who has never attempted to install anything inside a manhole. They will need to close the streets. You cannot just creep through the sewers installing stuff without disrupting the traffic above. Workers are not moles. They will need to run new lines. And in modern cities, the type without the huge walk-in storm sewers of NY/London/Paris/SF, there will still be digging. With many innovations these days it is hard to determine feasibility from initial articles/claims. Lots of inventions seem to exist only to get grant money, with no hope of practicality (solar roads, solar windows). If these are lightweight manhole covers that cannot support traffic (ie just an antenna mounted atop an aluminum cover) then I'll chalk it up alongside those sidewalk tiles that generate electricity from pedestrians: might work, but will never be practical. https://en.wikipedia.org/wiki/Solar_Roadways https://en.wikipedia.org/wiki/Solar_Roadways https://www.6sqft.com/pavegen-opens-worlds-first-smart-street-which-generates-electricity-from-footsteps/ https://www.6sqft.com/pavegen-opens-worlds-first-smart-stree...

deleted 8y ago
[deleted]
twic 8y ago
I don't think London has huge walk-in storm sewers. And there are certainly people digging up everything they can see, all the time, at least on the roads i use to get to work.
- deleted 8y ago
  [deleted]
- sandworm101 8y ago
  It does. The old cities have combined systems, storm and sewage together. To accommodate rainwater and maintenance, they are essentially brick corridors. Some are huge. https://www.telegraph.co.uk/sponsored/why-not/11621489/sewer-tours-in-london-and-brighton.html https://www.telegraph.co.uk/sponsored/why-not/11621489/sewer... More modern cities have separate systems for sewage and stormwater, and these are contained in small pipes that people cannot walk around in. Upgrading from a combined system is a massive project, well beyond something like 5g imho. https://www.thames21.org.uk/combined-sewer-systems/ https://www.thames21.org.uk/combined-sewer-systems/

shanghaiaway 8y ago

Wow, that must be why I start itching whenever I pass a manhole cover.

lifeisstillgood 8y ago

A side issue with 5G is that there are all sorts of fun / unusual effects being discovered with GSM/wifi suffusing our environments - i remember Stanford being able to detect people moving behind a wall using the wifi signals. Simply Monitoring signal strength has had many commercial opportunities and now we are going to put millimetre wave radar throughout our cities - expect novel uses to crop up

cypherpunks01 8y ago

Wouldn't traffic poles serve as better publicly-owned antenna mount points? They are powered and have better line of sight to everything (broader range). I wonder why manholes are considered better.

ajdhsjakafjt 8y ago
The article doesn't state it was better than traffic lights. I think small cells in traffic lights are already reality, even if not widespread, the small cells exist. The article presents a novel, non-obvious approach in some ealier-stage development.
ldite 8y ago
As I understand it, they're owned by different entities; the street lights/traffic poles are often owned by local authorities (in the UK) while manhole covers are owner by the utilities. I suspect that one aspect of this is to give them leverage in getting access to antenna sites.

chatterbeak 8y ago

_Person_ hole covers.

lykr0n 8y ago

The more I hear about 5G, the more I think it's an industry trying to sell a product that nobody is asking for. I have no complaints about the speed I get on my iPhone from T-Mobile here in the US. I wish I had better LTE coverage, but I'm happy with the performance. Most of the time it's snappier than my Wi-Fi (which is weird). I get a solid 8 to 20 mbits under fair conditions- I can stream movies and music just fine. All I hear about 5G is that it requires a large amount of antennas on both your phone (4 because a hand covering the antenna can cause a drop in signal) and around you. I don't want to be near a high power transmitter that's low frequency, and I really don't want to be near a high frequency one. What's the sell of 5G? I guess the speed, but what? 1 Gbit to my phone? Why. Considering that I only get 15GB of "Unlimited" data now, it isn't going to replace Wi-F. Because of the density required of the towers, it's not going to replace 4G/LTE as some areas it's just unrealistic to have the required density.

acchow 8y ago
You're still thinking in 2018 terms. What about 2025?
LeoPanthera 8y ago
640K ought to be enough for anybody.
awakeasleep 8y ago
Bandwidth is tremendously important in wireless communications because the more data you can transmit in less time, the less time you need to be transmitting. In general, only one radio can transmit on one frequency at a time. So a city wide network quickly becomes congested. Reducing the time everyone spends transmitting greatly increases the quality of service and the amount of users that can be serviced. The increased antenna count is also a benefit in crowded situations. If each antenna covers a smaller range, then more people can use the network in a given area- two antennas that would interfere with each other in a longer range system will operate simultaneously.
- lykr0n 8y ago
  They've solved that issue by deploying more towers in high density areas and carriers have swapped allocations in areas to get more continuous spectrum. Upping the frequency just gives you wider bands. I think a better argument could be made about spending R&D on making 4G/LTE require a smaller band. I think LTE (assuming 850MHz) can be 1.4, 3, 5, 10MHz per band- which is non-optional. If you could cut the required Tx/Rx band width in half; I think that would be better use of effort.

bjt2n3904 8y ago

When I was in college, I remember taking a class in silicon design. At one point, a student remarked, "man, silicon is like... black magic." "No," the teacher sharply rebuked. "It's governed by well understood and reliable mathematical equations. Though difficult, it is far from magic." There was a brief pause, the teacher was normally easy going and congenial. His harsh words caught us off guard. "...antennas on the other hand, that is black magic."

andreareina 8y ago
Indistinguishable From Magic: Manufacturing Modern Computer Chips -- https://www.youtube.com/watch?v=NGFhc8R_uO4 https://www.youtube.com/watch?v=NGFhc8R_uO4
- Joona 8y ago
  Same talk (slightly updated perhaps?) in higher quality: https://www.youtube.com/watch?v=KL-I3-C-KBk https://www.youtube.com/watch?v=KL-I3-C-KBk
  - andreareina 8y ago
    Didn't know about that, thanks!

liotier 8y ago

This means we may have to run power supplies to existing fiber manholes...

Uberphallus 8y ago

I'm far from an expert, but aren't manholes (and streetlights and traffic lights, by extension) effectively grounded, hence incurring into insane loss?

posterboy 8y ago
Came here to wonder the same. Do they wind a coil around it?
Johnythree 8y ago
Many Antennas are grounded (eg for lightning protection), but that has no relevance for their effectiveness as an antenna. Because the size is much less than a wavelength, the body can be at ground, while the active parts can be at RF potential. Example: Your phone is grounded, but it still works.
- Uberphallus 8y ago
  They are grounded with a precise length of coax (multiples of 1/4 or 1/2 wave, IIRC) to keep the VSWR ratio low for the intended frequency. In a pole you can get to do that by probing the signal at certain height, but the active part of a patch antenna (which I assume a manhole works as) is at the extremes of it (as such, probes are always off center for circular polarization, and at the extreme for linear), and those are grounded. Patch antennas are normally grounded at the center, as the voltage/current there should be close enough to 0 anyway unless there's an electrostatic discharge.