Ever wondered whether 5G would be good enough for Augmented and Virtual Reality or will we need to wait for 6G? Some researchers are trying to identify the AR / VR requirements, challenges from a mobile network point of view and possible options to solve these challenges. They have recently published a research paper on this topic.
Here is a summary of some of the interesting things I found in this paper:
Humans process nearly 5.2 gigabits per second of sound and light.
Without moving the head, our eyes can mechanically shift across a field of view of at least 150 degrees horizontally (i.e., 30:000 pixels) and 120 degrees vertically (i.e., 24:000 pixels).
The human eye can perceive much faster motion (150 frames per second). For sports, games, science and other high-speed immersive experiences, video rates of 60 or even 120 frames per second are needed to avoid motion blur and disorientation.
5.2 gigabits per second of network throughput (if not more) is needed.
At today’s 4K resolution, 30 frames per second and 24 bits per pixel, and using a 300 : 1 compression ratio, yields 300 megabits per second of imagery. That is more than 10x the typical requirement for a high-quality 4K movie experience.
5G network architectures are being designed to move the post-processing at the network edge so that processors at the edge and the client display devices (VR goggles, smart TVs, tablets and phones) carry out advanced image processing to stitch camera feeds into dramatic effects.
In order to tackle these grand challenges, the 5G network architecture (radio access network (RAN), Edge and Core) will need to be much smarter than ever before by adaptively and dynamically making use of concepts such as software defined networking (SDN), network function virtualization (NFV) and network slicing, to mention a few facilitating a more flexible allocating resources (resource blocks (RBs), access point, storage, memory, computing, etc.) to meet these demands.
Immersive technology will require massive improvements in terms of bandwidth, latency and reliablility. Current remotereality prototype requires 100-to-200Mbps for a one-way immersive experience. While MirrorSys uses a single 8K, estimates about photo-realistic VR will require two 16K x 16K screens (one to each eye).
Latency is the other big issue in addition to reliability. With an augmented reality headset, for example, real-life visual and auditory information has to be taken in through the camera and sent to the fog/cloud for processing, with digital information sent back to be precisely overlaid onto the real-world environment, and all this has to happen in less time than it takes for humans to start noticing lag (no more than 13ms). Factoring in the much needed high reliability criteria on top of these bandwidth and delay requirements clearly indicates the need for interactions between several research disciplines.
These key research directions and scientific challenges are summarized in Fig. 3 (above), and discussed in the paper. I advice you to read it here.
Last year Qualcomm announced the X16 LTE modem that was capable of up to 1Gbps, category 16 in DL and Cat 13 (150 Mbps) in UL. See my last post on UE categories here.
Early January, it announcedSnapdragon 835 at CES that looks impressive. Android central says "On the connectivity side of things, there's the Snapdragon X16 LTE modem, which enables Category 16 LTE download speeds that go up to one gigabit per second. For uploads, there's a Category 13 modem that lets you upload at 150MB/sec. For Wi-Fi, Qualcomm is offering an integrated 2x2 802.11ac Wave-2 solution along with an 802.11ad multi-gigabit Wi-Fi module that tops out at 4.6Gb/sec. The 835 will consume up to 60% less power while on Wi-Fi."
Technology purists would know that LTE, which is widely referred to as 4G, was in fact pre-4G or as some preferred to call it, 3.9G. New UE categories were introduced in Rel-10 to make LTE into LTE-Advanced with top speeds of 3Gbps. This way, the ITU requirements for a technology to be considered 4G (IMT-Advanced) was satisfied.
LTE-A was already Gigabit capable in theory but in practice we had been seeing peak speeds of up to 600Mbps until recently. With this off my chest, lets look at what announcements are being made. Before that, you may want to revisit what 4.5G or LTE-Advanced Pro is here.
Qualcomm, Telstra, Ericsson and NETGEAR Announce World’s First Gigabit Class LTE Mobile Device and Gigabit-Ready Network. Gigabit Class LTE download speeds are achieved through a combination of 3x carrier aggregation, 4x4 MIMO on two aggregated carriers plus 2x2 MIMO on the third carrier, and 256-QAM higher order modulation.
TIM in Italy is the first in Europe to launch 4.5G up to 500 Mbps in Rome, Palermo and Sanremo
Telenet in partnership with ZTE have achieved a download speed of 1.3 Gbps during a demonstration of the ZTE 4.5G new technology. That's four times faster than 4G's maximum download speed. Telenet is the first in Europe to reach this speed in real-life circumstances. 4.5G ZTE technology uses 4x4 MIMO beaming, 3-carrier aggregation, and a QAM 256 modulation.
AT&T said, "The continued deployment of our 4G LTE-Advanced network remains essential to laying the foundation for our evolution to 5G. In fact, we expect to begin reaching peak theoretical speeds of up to 1 Gbps at some cell sites in 2017. We will continue to densify our wireless network this year through the deployment of small cells and the use of technologies like carrier aggregation, which increases peak data speeds. We’re currently deploying three-way carrier aggregation in select areas, and plan to introduce four-way carrier aggregation as well as LTE-License Assisted Access (LAA) this year."
T-Mobile USA nearly reached a Gigabit and here is what they say, "we reached nearly 1 Gbps (979 Mbps) on our LTE network in our lab thanks to a combination of three carrier aggregation, 4x4 MIMO and 256 QAM (and an un-released handset)."
The other US operator Sprint expects to unveil some of its work with 256-QAM and massive MIMO on Sprint’s licensed spectrum that pushes the 1 gbps speed boundary. It’s unclear whether this will include an actual deployment of the technology
So we are going to see a lot of higher speed LTE this year and yes we can call it Gigabit LTE but lets not forget that the criteria for a technology to be real '4G' was that it should be able to do 1Gbps in both DL and UL. Sadly, the UL part is still not going Gigabit anytime soon.
Just noticed that the LTE UE Categories have been updated since I last posted here. Since Release-12 onwards, we now have a possibility of separate Downlink (ue-CategoryDL) and Uplink (ue-CategoryUL) categories.
From the latest RRC specifications, we can see that now there are two new fields that can be present ue-CategoryDL and ue-CategoryUL.
People who follow me on Twitter may have often noticed I put photos when I am doing surveys, field testing, debugging, etc. In the good old days we often had to carry a lot of different kind of specialised test equipment to do basic measurements. Nowadays a lot of these can be done with the help of free apps on Android phones. The best tool that can provide a great amount of info is Qualcomm's QXDM but its really expensive.
Here are a few tools that I use. If you have one that I havent listed below, please add it in comments.
The screen shot shows the main tools along with my favourite, SpeedTest. While I agree that Speedtest is not the most reliable approach to speed of your connection, I think its the most standard one being used.
WiFi Analyzer is another great app that can be used at home and other locations where people complain about not getting good WiFi speeds. I have been at locations where the 2.4GHz is absolutely packed with APs. 5GHz is also getting busier, though there are still a lot of free channels.
G-NetTrack Lite is a great tool to keep track of the cells you have been visiting. In case you are driving this can collect a lot of valuable info. The paid version, G-NetTrack Pro can collect the info in form of a map that can be used for offline viewing with the help of Google Earth.
I use LTE Discovery mainly for finding the band I am currently camped on. It would be great if a tool can give the exact frequency and earfcn but the band is good enough too. I was once in a situation where I could see two different cells but they had the same PCI. Only after using this, I figured out they were on different bands.
Finally, Network Cell Info Lite gives neighbour cells which can often be useful. I am not sure of these are the neighbours from System Info or from Measurement Control messages sent by network or just something like Detected cells that the phone sees around.
Pind and IPConfig are other tools that can come handy sometimes.
Are there any other tools that you like? Please share using comments.
Enter 5G and the problem could be be made much worse. With high speed data transfer and signalling, these devices can create an instantaneous attack on a very large scale and generating signalling storm that can take a network down in no time.
Giuseppe TARGIA, Nokia presented an excellent summary of some of these issues at the iDate Digiworld Summit 2016. His talk is embedded below:
You can check out many interesting presentations from the iDate Digiworld Summit 2016 on Youtube and Slideshare.
I am sure that by now everyone is aware of Facebook's attempt to connect the people in rural and remote areas. Back in March they published the State of Connectivity report highlighting that there are still over 4 billion people that are unconnected.
The chart above is very interesting and shows that there are still people who use 2G to access Facebook. Personally, I am not sure if these charts take Wi-Fi into account or not.
In my earlier post in the Small Cells blog, I have made a case for using Small Cells as the best solution for rural & remote coverage. There are a variety of options for power including wind turbines, solar power and even the old fashioned diesel/petrol generators. The main challenge is sometimes the backhaul. To solve this issue Facebook has been working on its drones as a means of providing the backhaul connectivity.
Recently Facebook held its first Telco Infra Project (TIP) Summit in California. The intention was to bring the diverse set of members (over 300 as I write this post) in a room, discuss ideas and ongoing projects.
There were quite a few interesting talks (videos available here). I have embedded the slides and the talk by SK Telecom below but before I that I was to highlight the important point made by AMN.
As can be seen in the picture above, technology is just one of the challenges in providing rural and remote connectivity. There are other challenges that have to be considered too.
Embedded below is the talk provided by Dr. Alex Jinsung Choi, CTO, SK Telecom and TIP Chairman and the slides follow that.
This post contains summary of three interesting events that took place recently.
CW (Cambridge Wireless) organised a couple of debates on 5G as can be seen from the topics above. Below is the summary video and twitter discussion summary/story.
Some of you may be unaware that the US operator Verizon has formed 'Verizon 5G Technology Forum' (V5GTF) with the intention of developing the first set of standards that can also influence the direction of 3GPP standardization and also provide an early mover advantage to itself and its partners.
The following from Light Reading news summarizes the situation well:
Verizon has posted its second round of work with its partners on a 5G specification. The first round was around the 5G radio specification; this time the work has been on the mechanics of connecting to the network. The operator has been working on the specification with Cisco Systems Inc., Ericsson AB, Intel Corp., LG Electronics Inc., Nokia Corp., Qualcomm Inc. and Samsung Corp. via the 5G Technology Forum (V5GTF) it formed late in 2015. Sanyogita Shamsunder, director of strategy at Verizon, says that the specification is "75% to 80% there" at least for a "fixed wireless use case." Verizon is aiming for a "friendly, pre-commercial launch" of a fixed wireless pilot in 2017, Koeppe notes.
Before we go further, lets see this excellent video by R&S wherein Andreas Roessler explains what Verizon is up to:
Verizon and SKT are both trying to be the 5G leaders and trying to roll out a pre-standard 5G whenever they can. In fact Qualcomm recently released a 28 GHz modem that will be used in separate pre-standard 5G cellular trials by Verizon and Korea Telecom
The Snapdragon X50 delivers 5 Gbits/second downlinks and multiple gigabit uplinks for mobile and fixed-wireless networks. It uses a separate LTE connection as an anchor for control signals while the 28 GHz link delivers the higher data rates over distances of tens to hundreds of meters.
The X50 uses eight 100 MHz channels, a 2x2 MIMO antenna array, adaptive beamforming techniques and 64 QAM to achieve a 90 dB link budget. It works in conjunction with Qualcomm’s SDR05x mmWave transceiver and PMX50 power management chip. So far, Qualcomm is not revealing more details of modem that will sample next year and be in production before June 2018.
Verizon and Korea Telecom will use the chips in separate trials starting late next year, anticipating commercial services in 2018. The new chips mark a departure from prototypes not intended as products that Qualcomm Research announced in June.
Korea Telecom plans a mobile 5G offering at the February 2018 Winter Olympics. Verizon plans to launch in 2018 a less ambitious fixed-wireless service in the U.S. based on a specification it released in July. KT and Verizon are among a quartet of carriers that formed a group in February to share results of early 5G trials.
For its part, the 3GPP standards group is also stepping up the pace of the 5G standards efforts it officially started earlier this year. It endorsed last month a proposal to consider moving the date for finishing Phase I, an initial version of 5G anchored to LTE, from June 2018 to as early as December 2017, according to a recent Qualcomm blog.
Coming back to Verizon's 5G standard, is it good enough and compatible with 3GPP standards? The answer right now seems to be NO.
The issue is that Verizon’s specs include a subcarrier spacing value of 75 kHz, whereas the 3GPP has laid out guidelines that subcarrier spacing must increase by 30 kHz at a time, according to research from Signals Research Group. This means that different networks can work in synergy if required without interfering with each other. Verizon’s 5G specs do stick to 3GPP requirements in that it includes MIMO and millimeter wave (mmWave). MmWave is a technology that both AT&T and Verizon are leading the way in – which could succeed in establishing spectrum which is licensed fairly traditionally as the core of the US’s high frequency build outs. A Verizon-fronted group recently rejected a proposal from AT&T to push the 3GPP into finalizing an initial 5G standard for late 2017, thus returning to the original proposed time of June 2018. Verizon was supported by Samsung, ZTE, Deutsche Telecom, France Telecom, TIM and others, which were concerned the split would defocus SA and New Radio efforts and even delay those standards being finalized. Verizon has been openly criticized in the industry, mostly by AT&T (unsurprisingly), as its hastiness may lead to fragmentation – yet it still looks likely to beat AT&T to be the first operator to deploy 5G, if only for fixed access. Verizon probably wants the industry to believe that it was prepared for eventualities such as this – prior to the study from Signal Research Group, the operator said its pre-standard implementation will be close enough to the standard that it could easily achieve full compatibility with simple alterations. However, Signals Research Group’s president Michael Thelander has been working with the 3GPP since the 5G standard was birthed, and he begs to differ. Thelander told FierceWireless, “I believe what Verizon is doing is not hardware-upgradeable to the real specification. It’s great to be trialing, even if you define your own spec, just to kind of get out there and play around with things. That’s great and wonderful and hats off to them. But when you oversell it and call it 5G and talk about commercial services, it’s not 5G. It’s really its own spec that has nothing to do with Release 16, which is still three years away. Just because you have something that operates in millimeter wave spectrum and uses Massive MIMO and OFDM, that doesn’t make it a 5G solution.”
Back in the 3G days, NTT Docomo was the leader in standards and it didn't have enough patience to wait for 3GPP standards to complete. As a result it released its first 3G network called FOMA (Freedom of Mobile Access) based on pre-standard version of specs. This resulted in handset manufacturers having to tweak their software to cope with this version and it suffered from economy of scale. Early version of 3G phones were also not able to roam on the Docomo network. In a way, Verizon is going down the same path.
While there can be some good learning as a result of this pre-5G standard, it may be a good idea not to get too tied into it. A standard that is not compliant will not achieve the required economy of scale, either with handsets or with dongles and other hotspot devices.
3GPP has recently completed the Initial Cellular V2X standard. The following from the news item:
The initial Cellular Vehicle-to-Everything (V2X) standard, for inclusion in the Release 14, was completed last week - during the 3GPP RAN meeting in New Orleans. It focuses on Vehicle-to-Vehicle (V2V) communications, with further enhancements to support additional V2X operational scenarios to follow, in Release 14, targeting completion during March 2017.
The 3GPP Work Item Description can be found in RP-161894.
V2V communications are based on D2D communications defined as part of ProSe services in Release 12 and Release 13 of the specification. As part of ProSe services, a new D2D interface (designated as PC5, also known as sidelink at the physical layer) was introduced and now as part of the V2V WI it has been enhanced for vehicular use cases, specifically addressing high speed (up to 250Kph) and high density (thousands of nodes). ...
For distributed scheduling (a.k.a. Mode 4) a sensing with semi-persistent transmission based mechanism was introduced. V2V traffic from a device is mostly periodic in nature. This was utilized to sense congestion on a resource and estimate future congestion on that resource. Based on estimation resources were booked. This technique optimizes the use of the channel by enhancing resource separation between transmitters that are using overlapping resources.
The design is scalable for different bandwidths including 10 MHz bandwidth.
Based on these fundamental link and system level changes there are two high level deployment configurations currently defined, and illustrated in Figure 3.
Both configurations use a dedicated carrier for V2V communications, meaning the target band is only used for PC5 based V2V communications. Also in both cases GNSS is used for time synchronization.
In “Configuration 1” scheduling and interference management of V2V traffic is supported based on distributed algorithms (Mode 4) implemented between the vehicles. As mentioned earlier the distributed algorithm is based on sensing with semi-persistent transmission. Additionally, a new mechanism where resource allocation is dependent on geographical information is introduced. Such a mechanism counters near far effect arising due to in-band emissions.
In “Configuration 2” scheduling and interference management of V2V traffic is assisted by eNBs (a.k.a. Mode 3) via control signaling over the Uu interface. The eNodeB will assign the resources being used for V2V signaling in a dynamic manner.
5G Americas has also published a whitepaper on V2X Cellular Solutions. From the press release: Vehicle-to-Everything (V2X) communications and solutions enable the exchange of information between vehicles and much more - people (V2P), such as bicyclists and pedestrians for alerts, vehicles (V2V) for collision avoidance, infrastructure (V2I) such as roadside devices for timing and prioritization, and the network (V2N) for real time traffic routing and other cloud travel services. The goal of V2X is to improve road safety, increase the efficiency of traffic, reduce environmental impacts and provide additional traveler information services. 5G Americas, the industry trade association and voice of 5G and LTE for the Americas, today announced the publication of a technical whitepaper titled V2X Cellular Solutions that details new connected car opportunities for the cellular and automotive industries.
The whitepaper describes the benefits that Cellular V2X (C-V2X) can provide to support the U.S. Department of Transportation objectives of improving safety and reducing vehicular crashes. Cellular V2X can also be instrumental in transforming the transportation experience by enhancing traveler and traffic information for societal goals. C-V2X is part of the 3GPP specifications in Release 14. 3GPP announced the completion of the initial C-V2X standard in September 2016. There is a robust evolutionary roadmap for C-V2X towards 5G with a strong ecosystem in place. C-V2X will be a key technology enabler for the safer, more autonomous vehicle of the future.
