Written by WiFiRanger Ambassador, Joel Weiss “docj”
To the average person, today’s cellular data marketplace is a jumble of technobabble. Carriers continuously boast of the capabilities of their networks while also claiming that even better service is soon to be available. At the same time several companies planning to establish satellite-based internet systems claim that users will be better off with those (when they exist)! If only there was a way to sift through the “Geek speak” to better understand what the situation actually is!
The acronym 4G LTE actually stands for 4th Generation Long Term Evolution and, believe it or not, it is even a registered trademark. It pertains to cellular transmission standards that were first proposed all the way back in 2004. To be called 4G LTE a cellular system has to be capable of providing at least 100 Mbps capability. 4G LTE is in use essentially all over the world and LTE phones can, with some specific exceptions, be used in most countries. 4G LTE replaced the 3G CDMA network used by some US carriers and that network will be shut down in the near future.
Even though people (and advertisers) use the terms 4G and LTE as if they are synonyms, in reality, the term LTE encompasses futures evolution beyond 4G.
So if LTE is what we have today, what comes next? I’ve heard people talk about Advanced LTE; is that the same as 5G?
Advanced 4G LTE is an improvement on “regular” 4G LTE but it doesn’t represent a whole new technology…For properly equipped cell towers and receivers (phones) Advanced 4G, sometimes called LTE+ in ads, can provide increased download speeds, up to ~300Mbps. To enable this, the cellular network essential permits a receiver to make multiple simultaneous connections to the network. It’s as if you phone or hotspot had two or more parallel connections to the same cellular tower. In “Geek speak” this is called carrier aggregation!
For carrier aggregation to work, the modem in your phone (the device that actually talks to the cellular network) has to be of an advanced type and it has to be communicating with a tower that has the proper hardware on it. Suffice it to say that at present, most of your phone and hotspots won’t yet support this capability and it is not uniformly available in the US.
To make matters even more confusing, some marketing flacks at AT&T decided to create a non-existent standard that they called “5Ge” which is nothing more than AT&T’s implementation of 4G LTE+. Irrespective of anything you hear in an ad, 5Ge is NOT 5G
So, if we don’t yet even have LTE+ why are we worrying about 5G? What would be different about 5G?
The 5G cellular system will be a completely new cellular implementation that will enable users to experience download speeds up to the Gbps range. Although, the actual speed obtained by users on any specific tower will probably be less than that, on the average most people will see download speed improvement of factors of at least 10 to 100. In addition, one of the advantages of 5G will be greatly reduced “ping times” (the time it takes for your “click” to reach the computer on the receiving end.) That would mean that a cellular connection would have plenty of bandwidth to support multiple video streams and/or to engage in real-time gaming
5G technology actually will come in three “flavors” and the implementation you encounter will depend significantly on which carrier you subscribe with and where you live. Different carriers have purchased the rights to use different sets of frequencies for their own 5G implementation. Furthermore, 5G implementation will be different in different parts of the country depending on the population density.
The following graphic depicts a portion of the electromagnetic spectrum and how our current and proposed communications networks fit together. The orange oval in the 0.8-2 GHz region is where today’s cellular phones and hotspots operate. The red oval shows the general spectral region called millimeter wave where the highest performance 5G systems will operate.
At the high performance end of the 5G spectrum there will be very high frequency 5G using what some people refer to as “millimeter waves.” The good news is that systems using mm waves will be capable of download speeds in the ~10 Gbps range. These transmissions will use frequencies of around 25 GHz. The bad news is that these wave are easily blocked by the walls of buildings, trees, rain and other obstacles and there will have to be many small “towers” to serve an area compared with the relatively small number of large towers we have today. Most people expect that this high frequency 5G will mostly be limited to urban and/or suburban environments.
At somewhat lower frequencies, in the 1-6 GHz range, there will be other implementations of 5G. Sprint had made investments in this frequency spectrum and other carriers are expected to use it also. Signals at these slightly lower frequencies will penetrate buildings and other obstacles better than do mm waves, but they won’t have quite as much penetration capability as we are used to with cellular signals today. The download speeds provided by 5G systems operating at these frequencies will be somewhat less than those made possible in the mm wave region.
At the lower end of the spectrum, there will be “low frequency” 5G and the carrier most aggressively pursuing this approach is T-Mobile which made a large investment in frequencies around 600 MHz, the so-called Band 71. T-Mobile is already using Band 71 for 4G LTE service, but later in 2020 it is expected to begin 5G operations using the same band . However, existing phones and hotspots that can receive Band 71 will not, in general, be able to receive 5G broadcasts on Band 71.
Furthermore, the physics of low frequency transmissions, however, limits 5G using these low frequencies to download speeds of ~100 Mbps. That might not compare with the Gbps speeds of higher frequency approaches, but it is sure a lot faster than the 1-10 Mbps speeds many of us live with today!
Wow, that’s a lot of information. When will all this happen?
5G is currently being rolled out by all the major carriers and is available in quite a few major metro areas. Here’s an interactive map of where you can already get 5G: https://www.digitaltrends.com/mobile/5g-availability-map/
It will probably take a number of years before the mix of technologies being offered by different carriers shakes out completely. Since I live in a relatively rural area, I doubt I’m going to see much of anything any time soon! But, no doubt our grandchildren will grow up in a word in which everything is wireless. “Grandpa, what’s that funny dish-like thing on the roof of your RV?”