14 ms·

5G Mobile Networks: A Systems Approach

166 points by mhandley 7y ago

erdaniels 7y ago
I’ve only skimmed through this but I wish there were more books and references written in such a manner. I typically find concepts like these harder to grasp but this lays it out in such a way that makes it easier to grok. Nice work!
wallflower 7y ago
I heard the real reason we need 5G is to sell more new phones. Thinner and bigger and better cameras isn’t enough anymore. However, mobile phones running 5G radios will deplete their battery far more rapidly than LTE, right? And that is assuming the 5G phone user is in a major metropolitan area where there is sufficient coverage to begin with.
- baybal2 7y ago
  > I heard the real reason we need 5G is to sell more new phones. Yes, and to force change of technical platform. It is harder to persuade carriers to do 4G properly, than to give them a brand new deal. For example we would likely never see VoLTE interoperability. Another factor is that Chinese companies really want it, because they have most of IP on it, and they don't want to "walk on the minefield" laid by patent trolls when they venture to Western markets. > However, mobile phones running 5G radios will deplete their battery far more rapidly than LTE, right? Yes, DSPs inside 5G basebands have more flops and SRAM than the main CPU. Imagine an eighties era supercomputer in your pocket.
  - MrRadar 7y ago
    > For example we would likely never see VoLTE interoperability. In the US at least we will have to get there eventually. The major US carriers are all killing 2G and 3G in the early 2020s[1] and due to FCC 911 requirements (you basically have to be able to call 911 if you can connect a phone to a network), not to mention basic voice roaming support, that means all VoLTE phones will have to (eventually) support VoLTE on any network. [1] https://www.multitech.com/documents/publications/marketing-guides/MT_Anticipated_Sunset_Cellular_Carriers_PDF.pdf https://www.multitech.com/documents/publications/marketing-g...
- dmos62 7y ago
  You bring up some valid points. I traveled to China recently. Phones like iPhone 5 practically don't work there, because the specifications supported by these phones are phased out to such a degree that you're hard pressed to find coverage even in urban areas. I.e. 4G and 5G made the older specs obsolete, so you're obligated to buy a newer device. Though, I guess it's possible that these bands were never supported in China. If anyone cares to chime in.
  - henrikeh 7y ago
    The Chinese telcos developed their own 3G standard called TD-CDMA. Note that 3G refers to a family or classification of network technologies, and the same is true for the other G’s. As an example CDMA2000 and UMTS are both competing 3G standards.
- Nokinside 7y ago
  5G is designed to be more energy efficient than 4G/LTE and it will be. The design goal was at least three days for smartphones and up to 15 years for IoT devices. 5G NG encoding requires more computational power but the but the transmission is more energy efficient. For operators the ability to put base stations into sleep mode is a big deal.
- LeonM 7y ago
  Yes, for the first couple of years 5G will be a marketing thing (5 is more than 4, so it _must_ be better). It helps manufacturers sell more devices and telcos to convince people to upgrade their plan. My opinion is that we don't really need 5G for portable devices (phones, tablets, etc). I'd like to argue that there are no services that would benefit from the higher bandwidth and lower latency that 5G offers over 4G. 5G does have benefits for stuff like IOT, but not for mobile devices imo. The current pricing schemes of telcos also don't make sense with the bandwidth capabilities of 5G. I have a 'premium' plan with 10GB of data per month, with 4G I can (in theory) already deplete that 10GB in 80 seconds. With 5G I could theoretically deplete that in less than 10 seconds.
- est31 7y ago
  Newer standards like LTE are incredibly more bandwidth efficient. This means that any phone that's still using the old standards uses up the bandwith that multiple newer phones could use. As free bandwith is extremely rare, at least in urban areas, network operators are pushing towards new standards. This phenomenon is real. E.g. in Germany the provider Deutsche Telekom has put a clause into their TOS that allows them to turn off 3G from 2020 onward (idk about their US daughter company T-Mobile USA). Yes, this means you as a citizen have to buy a new phone that supports 5G/LTE. But it's driven mainly by customer demands for bandwidth, not by evil phone makers that conspire with network operators.
- 7952 7y ago
  My theory is that it will be heavily sold to business to connect surveillance and other data hungry devices. It could be perfect for large landowners like a business park or industrial site.
tu7001 7y ago
Don't you think, that 5g is stupid idea, if masts have to by every, 200 - 300? meters, it will be terribly ugly, and how it's suppose to work in farms?
- maffydub 7y ago
  5G doesn't need masts every 200-300m. There are multiple different frequency bands you can use. The lowest frequencies are around the same as 4G, so you should need similar numbers of masts to get reasonable coverage. The highest are around 60GHz - these are pretty much line-of-sight and are likely to be used for shorter-range (but super-high-bandwidth) applications.
  - superkuh 7y ago
    What he means is that 5G offers only a ~15-20% increase in thoroughput with it's new set of modulation schemes given the same frequency span using 4G. So the increase in performance has to come from new frequency use. They'll steal half of C-band from satellite uplink but then all that's left is millimeter wave to truly get more thoroughput. And that does have the problem about the propagation characteristics.
    - merpnderp 7y ago
      Throughout isn’t the biggest advantage, it’s the vastly smaller time slicing allowing far more active connections.
    - maffydub 7y ago
      5G isn't just about bandwidth, though. There's quite a useful diagram at the bottom of https://techblog.comsoc.org/2017/03/02/itu-r-agrees-on-key-performance-requirements-for-imt-20205g/ https://techblog.comsoc.org/2017/03/02/itu-r-agrees-on-key-p... showing the three key use cases. As well as "Enhanced Mobile Broadband" (which does focus on increased bandwidth), there's also * "Massive IoT", which focuses on reducing power requirements and increasing the number of devices that can be served in a single cell (assuming they all transmit very little data) * "Low Latency", which focuses on better scheduling and quality of service.
NKosmatos 7y ago
Well written, clear and clean presentation, very good material inside for whoever wants to read more about 5G and mobile networks in general. Highly recommended!!!
whage 7y ago
Can someone help me understand what is usually meant by "systems" as in "A systems approach"?
- jordan_clark 7y ago
  I think in this context, it is meant to describe how the underlying hardware AND software work together and to describe the potential cloud (public or private) opportunities of both.
- bluGill 7y ago
  Systems as in looking at how the system fits together as a whole. This can often be as complex as the details of the individual parts. How do all the parts fit together. Example: If you are assigned to build a road you figure out the pavement so it can support the trucks driving over it. If you are assigned the system of the roads you instead look at where the trucks are going: is the route the road is on a good one (including will it hit kids on the way to school, are there good stores, will it induce demand and make things worse...), but you assume the pavement engineers will make the road strong enough.
- c4wrd 7y ago
  Systems Theory is the study of complex concepts in which those concepts are broken down into a comprehensive set of smaller, interconnected components that make it easier to understand the complexity and implement. Not the best example, but you can think of it as a blueprint of sorts.
bkovacev 7y ago
As someone new to the 5G world I'm hearing a lot about health concerns. Can someone please explain to me the actual health concerns? My GF has been talking about it for a while now, but when I looked up health related studies of 5G on google scholar - I didn't get any meaningful hits. Is it a tin foil thing or are there really some concerns?
- s_dev 7y ago
  It's a tin foil hat thing. It's just wireless frequencies -- which may have some minor impact but it wouldn't be any different to 4G or 3G really and you can see that tech came and hasn't caused any major health issues.
  - l0000p 7y ago
    Unfortunately, a statement like that, has just as much value as the conspiracy theory. Since 5G is a vastly different technology, the only thing we can say for certain is that we don't know the health risks at this point.
    - Nokinside 7y ago
      We know how the wavelengths penetrate into the body and how much power goes into the skin. In new 60 Ghz 5G wavelengths skin reflects 20-30% of the power and the rest is almost completely absorbed by the epidermis. Overall the power densities are so slow that there is no reason to except anything. Exposing skin to the sun is known radiation hazard. If you go outside during daytime why worry about 5G?
      - missosoup 7y ago
        > skin reflects 20-30% of the power and the rest is almost completely absorbed by the epidermis. So 70% of the energy is absorbed by the skin. What does that much energy at those freqs do to the epidermis? I don't know, you don't know. I'm not saying you're making a case for the conspiracy theories, but you're certainly not making one against them. > If you go outside during daytime why worry about 5G? If you go outside during daytime on an Australian summer day without sunscreen including underneath your clothing, you're going to get severe sunburn and permanently increase your chance of skin cancer in under 15 minutes. We have public awareness campaigns about this on TV and everything. Not a great comparison. I have no idea whether 5g freq ranges and power have health impacts, I'm just saying that clearly you don't either. You could repeat everything you said for 2.450 MHz and sound plausible, except that's the frequency of microwave ovens that cook things including humans. Do any molecules resonate at 5g freqs? I have no idea, neither do you.
0x445442 7y ago
Is there any hope of 5G providing internet service comparable to my current broadband offering? Competition for my home internet would be nice.
- grahamburger 7y ago
  That's exactly why companies are investing in 5G. There's not much benefit for consumers unless they can get you to cancel your cable and use them instead.
- Jhsto 7y ago
  Speed and latency wise it should be manageable, but the bigger problem is spectrum licenses. Depending on your local legislation, it might be that new competitors cannot do last-mile 5G delivery because the existing telecoms have purposefully lobbied and bought out all available spectrum.
gorillaJoe 7y ago
Just started reading, very informative so far. Nice to see what comes out from distilling the hype. This might help those that like to read on mobile like me: # from their git repo we can build arbitrary formats (requires python) git clone https://github.com/SystemsApproach/5G.git # generate an epub file inside of *_build/epub* make epub

166 points by mhandley 7y ago

I’ve only skimmed through this but I wish there were more books and references written in such a manner. I typically find concepts like these harder to grasp but this lays it out in such a way that makes it easier to grok. Nice work!

wallflower 7y ago

I heard the real reason we need 5G is to sell more new phones. Thinner and bigger and better cameras isn’t enough anymore. However, mobile phones running 5G radios will deplete their battery far more rapidly than LTE, right? And that is assuming the 5G phone user is in a major metropolitan area where there is sufficient coverage to begin with.

baybal2 7y ago
> I heard the real reason we need 5G is to sell more new phones. Yes, and to force change of technical platform. It is harder to persuade carriers to do 4G properly, than to give them a brand new deal. For example we would likely never see VoLTE interoperability. Another factor is that Chinese companies really want it, because they have most of IP on it, and they don't want to "walk on the minefield" laid by patent trolls when they venture to Western markets. > However, mobile phones running 5G radios will deplete their battery far more rapidly than LTE, right? Yes, DSPs inside 5G basebands have more flops and SRAM than the main CPU. Imagine an eighties era supercomputer in your pocket.
- MrRadar 7y ago
  > For example we would likely never see VoLTE interoperability. In the US at least we will have to get there eventually. The major US carriers are all killing 2G and 3G in the early 2020s[1] and due to FCC 911 requirements (you basically have to be able to call 911 if you can connect a phone to a network), not to mention basic voice roaming support, that means all VoLTE phones will have to (eventually) support VoLTE on any network. [1] https://www.multitech.com/documents/publications/marketing-guides/MT_Anticipated_Sunset_Cellular_Carriers_PDF.pdf https://www.multitech.com/documents/publications/marketing-g...
dmos62 7y ago
You bring up some valid points. I traveled to China recently. Phones like iPhone 5 practically don't work there, because the specifications supported by these phones are phased out to such a degree that you're hard pressed to find coverage even in urban areas. I.e. 4G and 5G made the older specs obsolete, so you're obligated to buy a newer device. Though, I guess it's possible that these bands were never supported in China. If anyone cares to chime in.
- henrikeh 7y ago
  The Chinese telcos developed their own 3G standard called TD-CDMA. Note that 3G refers to a family or classification of network technologies, and the same is true for the other G’s. As an example CDMA2000 and UMTS are both competing 3G standards.
Nokinside 7y ago
5G is designed to be more energy efficient than 4G/LTE and it will be. The design goal was at least three days for smartphones and up to 15 years for IoT devices. 5G NG encoding requires more computational power but the but the transmission is more energy efficient. For operators the ability to put base stations into sleep mode is a big deal.
LeonM 7y ago
Yes, for the first couple of years 5G will be a marketing thing (5 is more than 4, so it _must_ be better). It helps manufacturers sell more devices and telcos to convince people to upgrade their plan. My opinion is that we don't really need 5G for portable devices (phones, tablets, etc). I'd like to argue that there are no services that would benefit from the higher bandwidth and lower latency that 5G offers over 4G. 5G does have benefits for stuff like IOT, but not for mobile devices imo. The current pricing schemes of telcos also don't make sense with the bandwidth capabilities of 5G. I have a 'premium' plan with 10GB of data per month, with 4G I can (in theory) already deplete that 10GB in 80 seconds. With 5G I could theoretically deplete that in less than 10 seconds.
est31 7y ago
Newer standards like LTE are incredibly more bandwidth efficient. This means that any phone that's still using the old standards uses up the bandwith that multiple newer phones could use. As free bandwith is extremely rare, at least in urban areas, network operators are pushing towards new standards. This phenomenon is real. E.g. in Germany the provider Deutsche Telekom has put a clause into their TOS that allows them to turn off 3G from 2020 onward (idk about their US daughter company T-Mobile USA). Yes, this means you as a citizen have to buy a new phone that supports 5G/LTE. But it's driven mainly by customer demands for bandwidth, not by evil phone makers that conspire with network operators.
7952 7y ago
My theory is that it will be heavily sold to business to connect surveillance and other data hungry devices. It could be perfect for large landowners like a business park or industrial site.

tu7001 7y ago

Don't you think, that 5g is stupid idea, if masts have to by every, 200 - 300? meters, it will be terribly ugly, and how it's suppose to work in farms?

maffydub 7y ago
5G doesn't need masts every 200-300m. There are multiple different frequency bands you can use. The lowest frequencies are around the same as 4G, so you should need similar numbers of masts to get reasonable coverage. The highest are around 60GHz - these are pretty much line-of-sight and are likely to be used for shorter-range (but super-high-bandwidth) applications.
- superkuh 7y ago
  What he means is that 5G offers only a ~15-20% increase in thoroughput with it's new set of modulation schemes given the same frequency span using 4G. So the increase in performance has to come from new frequency use. They'll steal half of C-band from satellite uplink but then all that's left is millimeter wave to truly get more thoroughput. And that does have the problem about the propagation characteristics.
  - merpnderp 7y ago
    Throughout isn’t the biggest advantage, it’s the vastly smaller time slicing allowing far more active connections.
  - maffydub 7y ago
    5G isn't just about bandwidth, though. There's quite a useful diagram at the bottom of https://techblog.comsoc.org/2017/03/02/itu-r-agrees-on-key-performance-requirements-for-imt-20205g/ https://techblog.comsoc.org/2017/03/02/itu-r-agrees-on-key-p... showing the three key use cases. As well as "Enhanced Mobile Broadband" (which does focus on increased bandwidth), there's also * "Massive IoT", which focuses on reducing power requirements and increasing the number of devices that can be served in a single cell (assuming they all transmit very little data) * "Low Latency", which focuses on better scheduling and quality of service.

NKosmatos 7y ago

Well written, clear and clean presentation, very good material inside for whoever wants to read more about 5G and mobile networks in general. Highly recommended!!!

whage 7y ago

Can someone help me understand what is usually meant by "systems" as in "A systems approach"?

jordan_clark 7y ago
I think in this context, it is meant to describe how the underlying hardware AND software work together and to describe the potential cloud (public or private) opportunities of both.
bluGill 7y ago
Systems as in looking at how the system fits together as a whole. This can often be as complex as the details of the individual parts. How do all the parts fit together. Example: If you are assigned to build a road you figure out the pavement so it can support the trucks driving over it. If you are assigned the system of the roads you instead look at where the trucks are going: is the route the road is on a good one (including will it hit kids on the way to school, are there good stores, will it induce demand and make things worse...), but you assume the pavement engineers will make the road strong enough.
c4wrd 7y ago
Systems Theory is the study of complex concepts in which those concepts are broken down into a comprehensive set of smaller, interconnected components that make it easier to understand the complexity and implement. Not the best example, but you can think of it as a blueprint of sorts.

bkovacev 7y ago

As someone new to the 5G world I'm hearing a lot about health concerns. Can someone please explain to me the actual health concerns? My GF has been talking about it for a while now, but when I looked up health related studies of 5G on google scholar - I didn't get any meaningful hits. Is it a tin foil thing or are there really some concerns?

s_dev 7y ago
It's a tin foil hat thing. It's just wireless frequencies -- which may have some minor impact but it wouldn't be any different to 4G or 3G really and you can see that tech came and hasn't caused any major health issues.
- l0000p 7y ago
  Unfortunately, a statement like that, has just as much value as the conspiracy theory. Since 5G is a vastly different technology, the only thing we can say for certain is that we don't know the health risks at this point.
  - Nokinside 7y ago
    We know how the wavelengths penetrate into the body and how much power goes into the skin. In new 60 Ghz 5G wavelengths skin reflects 20-30% of the power and the rest is almost completely absorbed by the epidermis. Overall the power densities are so slow that there is no reason to except anything. Exposing skin to the sun is known radiation hazard. If you go outside during daytime why worry about 5G?
    - missosoup 7y ago
      > skin reflects 20-30% of the power and the rest is almost completely absorbed by the epidermis. So 70% of the energy is absorbed by the skin. What does that much energy at those freqs do to the epidermis? I don't know, you don't know. I'm not saying you're making a case for the conspiracy theories, but you're certainly not making one against them. > If you go outside during daytime why worry about 5G? If you go outside during daytime on an Australian summer day without sunscreen including underneath your clothing, you're going to get severe sunburn and permanently increase your chance of skin cancer in under 15 minutes. We have public awareness campaigns about this on TV and everything. Not a great comparison. I have no idea whether 5g freq ranges and power have health impacts, I'm just saying that clearly you don't either. You could repeat everything you said for 2.450 MHz and sound plausible, except that's the frequency of microwave ovens that cook things including humans. Do any molecules resonate at 5g freqs? I have no idea, neither do you.

0x445442 7y ago

Is there any hope of 5G providing internet service comparable to my current broadband offering? Competition for my home internet would be nice.

grahamburger 7y ago
That's exactly why companies are investing in 5G. There's not much benefit for consumers unless they can get you to cancel your cable and use them instead.
Jhsto 7y ago
Speed and latency wise it should be manageable, but the bigger problem is spectrum licenses. Depending on your local legislation, it might be that new competitors cannot do last-mile 5G delivery because the existing telecoms have purposefully lobbied and bought out all available spectrum.

gorillaJoe 7y ago

Just started reading, very informative so far. Nice to see what comes out from distilling the hype. This might help those that like to read on mobile like me: # from their git repo we can build arbitrary formats (requires python) git clone https://github.com/SystemsApproach/5G.git # generate an epub file inside of *_build/epub* make epub