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Antenna Design for 5G Communications

7 Jun

With the rollout of the 5th generation mobile network around the corner, technology exploration is in full swing. The new 5G requirements (e.g. 1000x increase in capacity, 10x higher data rates, etc.) will create opportunities for diverse new applications, including automotive, healthcare, industrial and gaming. But to make these requirements technically feasible, higher communication frequencies are needed. For example, the 26 and 28 GHz frequency bands have been allocated for Europe and the USA respectively – more than 10x higher than typical 4G frequencies. Other advancement will include carrier aggregation to increase bandwidth and the use of massive MIMO antenna arrays to separate users through beamforming and spatial multiplexing.

Driving Innovation Through Simulation

The combination of these technology developments will create new challenges that impact design methodologies applied to mobile and base station antennas currently. Higher gain antennas will be needed to sustain communications in the millimeter wavelength band due to the increase in propagation losses. While this can be achieved by using multi-element antenna arrays, it comes at the cost of increased design complexity, reduced beamwidth and sophisticated feed circuits.

Simulation will pave the way to innovate these new antenna designs through rigorous optimization and tradeoff analysis. Altair’s FEKO™ is a comprehensive electromagnetic simulation suite ideal for these type of designs: offering MoM, FEM and FDTD solvers for preliminary antenna simulations, and specialized tools for efficient simulation of large array antennas.

Mobile Devices

In a mobile phone, antenna real estate is typically a very limited commodity, and in most cases, a tradeoff between antenna size and performance is made. In the millimeter band the antenna footprint will be much smaller, and optimization of the antenna geometry will ensure the best antenna performance is achieved for the space that is allocated, also for higher order MIMO configurations.

At these frequencies, the mobile device is also tens of wavelengths in size and the antenna integration process now becomes more like an antenna placement problem – an area where FEKO is well known to excel. When considering MIMO strategies, it is also easier to achieve good isolation between the MIMO elements, due to larger spatial separation that can be achieved at higher frequencies. Similarly, it is more straightforward to achieve good pattern diversity strategies.

 

 

Base Station

FEKO’s high performance solvers and specialized toolsets are well suited for the simulation massive MIMO antenna arrays for 5G base stations. During the design of these arrays, a 2×2 subsection can be optimized to achieve good matching, maximize gain and minimize isolation with neighboring elements –a very efficient approach to minimize nearest neighbor coupling. The design can then be extrapolated up to the large array configurations for final analysis. Farming of the optimization tasks enables these multi-variable and multi-goal to be solved in only a few hours. Analysis of the full array geometry can be efficiently solved with FEKO’s FDTD or MLFMM method: while FDTD is extremely efficient (1.5 hrs for 16×16 planar array), MLFMM might also be a good choice depending on the specific antenna geometry.

 

 

The 5G Channel and Network Deployment

The mobile and base station antenna patterns that are simulated in FEKO, can used in WinProp™ for high-level system analysis of the 5G radio network coverage and to determine channel statistics for urban, rural and indoor scenarios.

 

 

WinProp is already extensively used for 4G/LTE network planning. However, the use cases for 5G networks will be even more relevant largely due to the different factors that occur in the millimeter band. These include higher path loss from atmospheric absorption and rainfall, minimal penetration into walls and stronger effects due to surface roughness.

In addition to being able to calculate the angular and delay spread, WinProp also provides a platform to analyze and compare the performance of different MIMO configurations while taking beamforming into account.

 

The Road to 5G

While some of the challenges that lie ahead to meet the 5G requirements may still seem daunting, simulation can already be used today to develop understanding and explore innovative solutions. FEKO offers comprehensive solutions for device and base station antenna design, while WinProp will determine the requirements for successful network deployment.

 

Source: http://innovationintelligence.com/antenna-design-for-5g-communications/

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What is mm wave and how does it fit into 5G?

16 Aug

Extremely high frequency’ means extremely fast 5G speeds

Millimeter wave, also known as extremely high frequency, is the band of spectrum between 30 gigahertzand 300 GHz. Wedged between microwave and infrared waves, this spectrum can be used for high-speed wireless communications as seen with the latest 802.11ad Wi-Fi standard (operating at 60 GHz). It is being considered by standards organization, the Federal Communications Commission and researchers as the way to bring “5G” into the future by allocating more bandwidth to deliver faster, higher-quality video, and multimedia content and services.

source: NI

Source: National Instruments

Earlier this year, Ted Rappaport, founding director of NYU Wireless, said mobile data traffic is projected to rise 53% each year into the “foreseeable future,” and over the last 40 years, computer clock speeds and memory sizes rose by as much as six orders of magnitude. We need higher frequency spectrum to accommodate the increases in data usage, and one of the greatest and most important uses of millimeter waves is in transmitting large amounts of data.

source: NI

Source: National Instruments

Today, mmWave frequencies are being utilized for applications such as streaming high-resolution video indoors. Traditionally however, these higher frequencies were not strong enough for indoor broadband applications due to high propagation loss and susceptibility to blockage from buildings as well asabsorption from rain drops. These problems made mmWave impossible for mobile broadband.

Too good to be true?

High frequency means narrow wavelengths, and for mmWaves that sits in the range of 10 millimeters to 1 millimeter. It’s strength can be reduced due to its vulnerabilities against gases, rain and humidity absorption. And to make things even less appealing, due to those factors, millimeter wavelengths only reach out to a few kilometers.

source: Microsoft

Source: Microsoft

Just a few years ago mmWave was not being put to use because few electronic components could receive millimeter waves. Now, thanks to new technologies, it is on the brink of being an integral part of the next-generation network.

The solutions

Thankfully, the same characteristics that make mmWave so difficult to implement can be used to combat its shortcomings.

Short transmission paths and high propagation losses allows for spectrum reuse by limiting the amount of interference between adjacent cells, according to Robert W. Heath, professor in the department of electrical and computer engineering at The University of Texas at Austin. In addition, where longer paths are desired, the extremely short wavelengths of mmWave signals make it feasible for very small antennas to concentrate signals into highly focused beams with enough gain to overcome propagation losses. The short wavelengths of mmWave signals also make it possible to build multielement, dynamic beamforming antennas that will be small enough to fit into handsets.

source: UT Austin

Source: UT Austin

How mmWave spectrum is being handled

Last October the FCC proposed new rules for wireless broadband in wireless frequencies above 24 gigahertz. According to the government organization, these proposed rules “are an opportunity to move forward on creating a regulatory environment in which these emerging next-generation mobile technologies – such as so-called 5G mobile service – can potentially take hold and deliver benefits to consumers, businesses, and the U.S. economy.”

According to the FCC, the organization is “taking steps to unlock the mobile broadband and unlicensed potential of spectrum at the frontier above 24 GHz.”

Service operators have begun investigating mmWave technology to evaluate the best candidate frequencies for use in mobile applications. The International Telecommunication Union and 3GPP have aligned on a plan for two phases of research for 5G standards. The first phase, completing September 2018, defines a period of research for frequencies less than 40 GHz to address the more urgent subset of the commercial needs. The second phase is slated to begin in 2018 and complete in December 2019 to address the KPIs outlined by IMT 2020. This second phase focuses on frequencies up to 100 GHz, according to National Instruments.

In an report titled Millimeter-wave for 5G: Unifying Communication and Sensing, Xinyu Zhang, assistant professor of the electrical and computer engineering at the University of Wisconsin, detailed the mmWave bands being considered:

  • 57 GHz to 64 GHz unlicensed;
  • 7 GHz in total 28 GHz/38 GHz licensed but underutilized; and
  • 3.4 GHz in total 71 GHz/81 GHz/92GHz Light-licensed band: 12.9 GHz in total
source: National Instruments

Source: National Instruments

The ITU released a list of proposed globally viable frequencies between 24 GHz and 86 GHz after the most recent World Radiocommunications Conference:

24.25–27.5GHz                                        31.8–33.4GHz

37–40.5GHz                                             40.5–42.5GHz

45.5–50.2GHz                                           50.4–52.6GHz

66–76GHz                                                      81–86GHz

Source: http://www.rcrwireless.com/20160815/fundamentals/mmwave-5g-tag31-tag99

Smart Antennae: Critical for 5G

14 Jan

The 5G Network of Tomorrow is coming to mobile broadband, and like SDN/NFV, it will generate new network operating models.While avant-garde operators will quickly adopt, further cementing their market leading positions, 5G will open the door to non-traditional network operators and infrastructure vendors for networks in unlicensed and shared licensed spectrum. Notably, the Radio Access Network will experience a major change, as the nature of 5G frequencies will change the design and operation of cellular networks.Knowing that 5G is a major change for operators with a legacy mindset, the development community is trying to deliver the maximum utility and longevity with a platform that should last for 10 years and avoid operators’ buyer remorse of “I wish we had known…”

What are the differences with 5G frequencies, and what can we expect from them? Today’s cellular frequencies range from 450 MHz to more than 3000 MHz—technical terms that have important physical and economic implications, and traditionally licensed spectrum. With 5G multi-connectivity, operators can use unlicensed spectrum for added capacity or develop isolated networks for enterprise and industrial applications.Because of the physics of electromagnetic radio waves, the lower numbered frequencies are able to reach farther and cover more area for less cost than the higher numbered frequencies. However, it is not a free lunch, because as more subscribers sign up, cell sites using the lower numbered frequencies will have too many subscribers for each base station, causing slow data rates and delivering a poor user experience. Operators can buy more radio spectrum (if available) and/or put up more cell sites, including small cells, to meet wireless broadband data demand. Smarter antenna systems will also improve network performance and capacity beyond what is capable with today’s standard 2×2 and 4×4 MIMO deployments in 4G LTE.

For cellular networks, the signal quality matters most for the user experience, and as a simple rule of thumb, a stronger signal (relative to the surrounding electronic noise) leads to a better user experience withfaster data rates.In the digital realm, blazing speed correlates with mass-market capacity, as all subscribers in a cell share the total data rate. Obtaining stronger signals with 5G involves smarter antenna technology, more radio spectrum, and smaller cells. The physics of 5G spectrum changes the economics for antenna solutions, as the higher frequencies equate to packing more antennae into a smaller space and remaining cost effective. The higher numbered frequencies are promising, because there is a lot of radio space available, which will help support a 1000x increase in traffic. Smaller cells and smart antennae offset the propagation physics that would otherwise mean a very short range and poor user experience.

5G will encompass a wide range of spectrum, but my primary interest is new frequencies above 6 GHz.At 28 GHz, for example, a single antenna, called a “half wavelength dipole,” is about 0.2 inches—not big at all.The small size spurs creative engineers to do many clever things, like beamforming.An array of antennae, say 128 elements, is still very small, but the right digital signal processing can generate a very focused beam from the base station to the mobile.This is necessary for the cellular signals to overcome the energy losses due to distance, buildings, trees, rain, or people.

At a recent 5G workshop, Qualcomm demonstrated a 28 GHz test setup with a 128 element antenna representing a base station, and a mock-up mobile with a smaller set of selectable antennae (read about the demo).The 128 element base station antenna was about 6”x8” and the ability to focus a radio beam was demonstrated under a variety of orientations. An antenna designed the same way for today’s LTE frequencies at 700 MHz would be about 20’x30’ and not feasible. An operator can hang an abundance of 6”x8” antennae in a place like Times Square, which leads back to another aspect of 5G—Massive MIMO (Multiple-Input, Multiple Output – who thinks up these names?). Massive MIMO essentially means that the network uses multiple antenna beams from multiple base stations to deliver the fastest data to your mobile.

The tiny smart antennae demonstrated by Qualcomm had about 27 db gain, about 10–12 more db than a typical cellular base station antenna. 10 db more means that antenna could put 10x more signal power on a mobile than a legacy cellular antenna. An analogy to this effect is like using a candle to light up a dark room versus using a flashlight. This focused approach also extends to the many antennae that might be deployed, that is several base stations with lots of antennae may deliver the signal to your mobile, hence Massive.The net effect is to provide you a stronger signal with less interference, or noise, from all the other mobiles nearby. The relative signal-to-noise ratio (SNR) limits how fast the network can deliver the data, and a bigger ratio is better. Beam Forming Smart Antennae makes for a larger signal value at the top of the ratio fraction, and smaller noise value at the bottom for a double boost to SNR.

A second aspect, and just as critical as the base station antenna, are mobile antennae. Qualcomm demonstrated a facsimile of a mobile, a Form Factor Accurate device, with antenna in the case edges, front and back, top and bottom.Many antennae are needed to make sure that at least some are unobstructed by your hand or other body parts. I expect that there are best practices in mobile antenna design that will come from this, so that 5G handset vendors will not have Antennagate déjà vu all over again.

A third critical aspect of a 5G cellular network will be multi-connectivity. 5G multi-connectivity means that while your network is delivering an outstanding data experience in the uber-fast 6 GHz (and higher) frequencies, it maintains additional connections with 4G LTE (Long Term Evolution – seriously, where do they get these names?). In spite of the multiple beam forming antennae that puts your device in the spotlight, there will be occasional times where the 28 GHz signal is blocked. Rather than drop off the network, the network maintains the connection through the wider coverage of 4G LTE until the 28 GHz signal returns.

The bigger picture of 5G is more than just the spectrum, antennae, anda faster-better-cheaper mobile broadband. The 5G Network of Tomorrow is about designing and operating the networks with the forethought and flexibility to last through 2030. The 5G network will bring to fruition the aspirations of the connected society, that is the Internet of Everything. Of course, none of this is simple to implement, but by connecting the dots among 4G, 5G, and millimeter wave smart antennae research, we have a good idea for key components of a 5G network. The creative geniuses at companies like Qualcomm are working diligently to make this happen.

 

Source: https://www.abiresearch.com/blogs/smart-antennae-critical-5g/

5G

LTE like you have never seen before, or you will never see at all…

19 Jun

We can be sure that the hunger for data transmission will grow rapidly and that the mobile networks will not be able to deliver the expected capacity. On top of the current avalanche of the data created and consumed by humans we will soon see a completely different order of magnitude of the traffic Not only traffic generated by the machines in so-called Internet of Things or Internet of Everything.

A year ago, 3GPP consortium was approached by the mighty Qualcomm with the proposal to include in the next release of the 3GPP specs the extensions of LTE Advanced framework into two very interesting options promising both dramatic increase of networks capacity and the local peering interfaces.

Promised land

The most rare resource in the mobile world are the frequencies operators can use to build their networks. Based on the old paradigm of licensing, giving the exclusivity of the spectrum usage to a certain entity are in fact the foundation of cellular carriers business model. They pay fortunes for the license and are the only landlords of the assigned band. Also the protocols running there (GSM/3G/4G/LTE) behave like the only kid on the block expecting no interference in the area and enforcing the exclusivity rights.

Quality of service predictability is linked to the exclusivity and the binary access to a given spectrum resource, at a given location and a given time.”

However the licensing model assigns very small spectrum to an operator. Those can be even highly-priced 5 MHz pieces! Very often the frequencies are fragmented and do not allow aggregation of the transmission channels which is vital to increase the data throughout. And since rarely operators decide to merge their frequency assets (like formation of Everything Everywhere by Orange and T-Mobile in the UK or NetworkS! in Poland), there seems to be no way out from the spectrum trap.

But wait a minute! There is a great open field out there – the unlicensed bands. Originating back from back in 1985, when so-called “junk bands” of 2.4 and 5.8 GHz were declared free to use by anyone, they are right now occupied mostly by WiFi (IEEE 802.11). Subsequently the set of the unlicensed frequencies got expanded and right now almost entire 5 GHz range is available – 775 MHZ of continuous spectrum. Recently released TV broadcasting bands (sub 1 GHz) are tested for long-range rural internet access and 60 GHz (massive 7 GHz cluster) is already used as either point-to-point connectivity or short-range multimedia streaming at home (802.11ad standard).

The free spectrum is not only home for WiFi, but also a place of co-existence of many other protocols – Bluetooth, Zigbee. Over time the base rules of the game were defined to guarantee problem-free common usage of the frequencies with good neighbours trying to limit the impact of their actions on the others lives.

How will a selfish kid like LTE behave in this good neighbourhood? It’s not like having a racetrack just for yourself. It’s more like driving a car in the city, where streets are available to everyone who is able to understand the rules and play by those rules. Will LTE learn the traffic or crash spectacularily?

The key to success

The proposal from Qualcomm defines LTE-U extension to use the U-NII-3 part of the 5 GHz band, which has highest EIRP emission power allowed. While in 2.4 GHz regulatory bodies limit EIRP to 100 mW (Europe) or 200 mW (USA), the U-NII-3 enjoys the rights to go as high as 1000 mW outdoors.
Yes – 1 watt of power…

However, the LTE will not move entirely to the unlicensed area. The postulate is to keep the control channel still operational in the reserved frequency so that “the crucial signaling information is always communicated properly.” Which also means that only true MNO will be able to deploy the technology. It’s a big goodbye kiss to the enterprises hoping they could build private LTE networks without licensing cost…

In fact the LTE-U proposal is built on another LTE Advanced standard extension called “carrier aggregation”. It allows using multiple communication channels to transfer data in parallel. Originally it was designed to solve the problem of the “frequency mosaic”. Instead of exchanging and merging the frequencies with the other players to gain higher bandwidths, mobile operators will be able to use the radio resource they have right now “as-is”. LTE-U is simply saying that instead of the owned frequencies, some channels will be formed in the 5 GHz band. Carrier aggregation is pretty adaptive structure, so we can end up in multiple, dynamically changing topologies where all links work in licensed channels, all work in unlicensed spectrum or we have a mixture. System shall adapt to the congestion of the mobile network and availability of the unlicensed frequencies.

Here is the key to the co-existence of the selfish LTE kid with WiFi – effective sensing of available resources without pre-empting all of them. Qualcomm argues that there will be no noticeable degradation of the competing WiFi networks, while allegedly more efficient LTE-U encoding will deliver larger capacity than neighboring 802.11 systems.

Feasibility of the LTE-U

Control channel for LTE-U still needs to be realized via licensed band so the technology is possible to be implemented only in the existing LTE coverage areas. Carriers already struggle with the overwhelming investments that are necessary for LTE rollouts. Will they be willing to add more money to the budget for the promised added capacity, seamless aggregation the unlicensed downlink channels and ability to transition VoLTE calls? Especially that in order to use the LTE-U, their subscribers will need to have fully-compatible terminal with newest chipset, which will not happen overnight.

It might be a good choice for the smaller players on the market strangled by the lack of spectrum and pressured by the quality demand from their customers. That could be a good selling point for them without otherwise unavoidable huge license fees infrastructure expenses.

On the other hand why shall they wait for the specification to be finalized and equipment to be available, while already they can build WiFi networks delivering the same added capacity, seamless roaming between radio networks and even voice transitioning from VoLTE to VoWiFi and back? Maybe because the intention is to make WiFi and other wireless technologies obsolete and take over full control over previously free area? Another Qualcomm extension to LTE Advanced seems to be a step into such direction.

Direct communication – reinvented

The future uber-connected world with everybody and everything talking to each other will likely consume all possible centralized network resources. Not only licensed , but also the previously mentioned unlicensed spectrum. Hence the concept of direct device-to-device communication without engaging of central management seems to be the way forward for some specific types of applications, like location of devices or social media check-ins or individual/group messaging.

Nowadays such applications are based either on modified Bluetooth protocols or exisiting blanket coverage WiFi networks. Using the characteristics of those systems and add-on modules in the operating systems of our smartphones or tablets, it is possible to locate the user in the indoor environment and trigger some action.

Typical example is the shopping assistance. Wandering in the vast public venue like a shopping mall frequently requires some “indoor navigation” aid. Positioning of the customer gives also the opportunity to analyze the behavior of the visitors and pushing to them marketing messages when they enter certain zones (eg. promo messages when passing by a shop which paid for such advertisement). All based on the assumption that the user has got his WiFi and Bluetooth modules active and his terminal is equipped with the application able to receive such information.

LTE Direct proposed by Qualcomm taps on this opportunity by replacing WiFi/BT communication with yet another LTE Advanced extension. It is using as little as <1% of the network signaling, yet provides direct messaging between user devices. There are two types of messages defined – public and private expressions.

Public expressions are exactly matching the Bluetooth iBeacon functionality. They can be used to locate the user and push any kind of message to his device. The messages are not filtered and do not require applications to be presented to the customer. Excellent marketing tool with larger than iBeacon range (ca. 500 meters instead of 50), promised lower power consumption and better accuracy. Moreover working both outdoors and under roof.

Private expressions are linked with particular messaging/presence app and can be subject to special filtering and privacy settings enforced already on the device chipset level. They can be used to communicate with friends wishing to join the party, seek for people with the same interests at an event or simply as next generation social messaging with geo-location context.

In order to work, LTE Direct still needs licensed spectrum and the LTE control channel. It means that, just like LTE-U, its applicability is strongly dedicated to the mobile carriers and not the enterprises. Exactly opposite to the current beneficiaries of location based services, which are public venues of different kinds: shopping malls, transportation hubs or hospitality properties. One might even interpret such definition of the standard as an attempt to bring back to the operators the opportunity to tap on the revenues right now leaking to such enterprises or OTT (over the top) application owners like Facebook or Google. Bringing back human-to-human communication management (and payments) to the carriers. Especially in the context of classical texting and phone call role diminishing. Finally they could charge again for the actual usage of the network and not just deliver the capacity.

However, there are still some unresolved issues with LTE Direct. While WiFi and Bluetooth work in “neutral host” mode and serve all the user devices, irrespectively of the actual mobile operator and even the ones which are not equipped with cellular interface, LTE Direct requires one common signaling band. The open question remains if the operators will be able to agree on one shared control frequency and under which conditions. Especially that such arrangement shall work for their entire coverage area in order for this extension to be a valid upsell option.

Busines case

Both extensions are part of the new 3GPP releases and expected to approved and possible to implement in 2015-2016 timeframe. As part of the LTE Advanced rollout effort, they require substantial investment in the infrastructure (order of magnitude more expensive than WiFi), but above all – compatible user devices. Low number of termials might limit the business feasibility of such “unlicensed offload” or added-value services, while WiFi and BT are already present in all mobile phones (standard supported globally) and are usable immediately. Also majority of tablets, mobile computers and the expected Internet of Everything devices are SIM-less. This dooms LTE-U/Direct to be just an auxiliary, “nice to have” service for years and only few most desperate operators will decide to go their way.

The WiFi revolution seems to be progressing faster than LTE-A and can make a lot of the mobile carrier business obsolete? We already spend 85% of our time in the coverage of WiFi. Do we really need SIM cards for communication? Do we really need phone calls to talk? Maybe it’s time to kill the phone call? SIM-less future?

Pictures and diagrams are from Qualcomm and Aptilo materials.

 

Source: https://www.linkedin.com/pulse/20141114180540-5689549-%E9%80%B2%E6%92%83%E3%81%AE%E5%B7%A8%E4%BA%BA-shingeki-no-kyojin

5 Years to 5G: Enabling Rapid 5G System Development

13 Feb

As we look to 2020 for widespread 5G deployment, it is likely that most OEMs will sell production equipment based on FPGAs.

5G round-up: Everything you need to know

30 Jan

Universities, governments and telecoms companies are investing stupendous amounts of time and money into the development of 5G, but what is it and how will it benefit us over and above what both 3G and 4G networks are currently able to deliver? How will it change the mobile industry and when can we expect to start using it?

The past: the birth of mobile internet

5G is purported to deliver data speeds that are literally thousands of times faster than 4G

What is 5G?

Unsurprisingly, it’s the next generation after 4G

5G is the next generation of mobile technology. A new generation of mobile standards has appeared roughly every 10 years since analogue systems – which later became known as 1G – were introduced in 1981.

2G was the first to use digital radio signals and introduced data services, including SMS text messages; 3G brought us mobile internet access and video calls; 4G, which has been rolled out in the UK since 2012, provides faster and more reliable mobile broadband internet access.

It will use higher frequency spectrum than current networks

5G, like its predecessors, is a wireless technology that will use specific radio wavelengths, or spectrum. Ofcom, the UK telecoms regulator, has become involved early in its development and has asked mobile operators to help lay the foundations for the technology. That’s because in order to achieve the best possible speeds, it will need large swathes of this high-frequency spectrum, some of which is already being used by other applications, including the military.

The frequencies in question are above 6GHz – currently used for satellite broadcasting, weather monitoring and scientific research.

What will I be able to do on 5G?

Download a film in under a minute

Fifth generation networks will feature improved web browsing speeds as well as faster download and upload speeds. O2 told Cable.co.uk that 5G will offer “higher speed data communication” than 4G, allowing users to “download a film in under a minute, add lower latency (the time lag between an action and a response) and reduce buffering and add more capacity”.

According to Ericsson, 5G will help to create more reliable and simpler networks that will open up a world of practical uses such as the remote control of excavating equipment or even remote surgery using a robot.

Vice president Magnus Furustam, head of product area cloud systems, speaking to Cable.co.uk at the Broadband World Forum in Amsterdam, said: “What 5G will bring is even more reliable networks, better latency, you will see networks penetrating into areas they previously haven’t.

“You will see smaller cells [network transmitters or masts], you will see higher bandwidth, you will see more frequencies being used, you will basically see mobile broadband networks reaching further out, both from a coverage perspective as well as from a device perspective.”

5G will give the impression of infinite capacity

Speaking to Cable.co.uk at the International Consumer Electronics Show earlier this month, Ramneek Bali, a technical solutions manager for Ericsson, said 5G “is going to enable the networked society.

“When we say networked society, basically you’ve heard of the internet of things, connected devices, connected cars, even high throughput – 5G is going to enable all that.”

The University of Surrey’s 5G Innovation Centre (5GIC), meanwhile, which is working alongside companies including Huawei, Vodafone and Fujitsu, has set the 5G network a target of ‘always having sufficient rate to give the user the impression of infinite capacity’ by understanding the demands of the user and allocating resources where they are needed.

The past: the birth of mobile internet

5G will deliver the low latency and reliability needed for operations to be carried out remotely using robotic arms

How fast will 5G be?

5G will be 3,333 times faster than 4G

5G is expected to deliver data speeds of between 10 and 50Gbps, compared to the average 4G download speed which is currently 15Mbps.

Huawei’s report ‘5G: A Technology Vision’ says a 5G network will be required to deliver data rates of at least 1Gbps to support ultra HD video and virtual reality applications, and 10Gbps data rates for mobile cloud services.

5G will have ‘near-zero’ latency

Latency will be so low – less than one millisecond – that it will be imperceptible to humans and the switching time between different radio access technologies (cellular networks, wi-fi and so on) will take a maximum of 10 milliseconds.

Ericsson has trialled 5G technology with Japanese carrier NTT Docomo, announcing that its “pre-standard” technology had already achieved speeds of 5Gbps. Samsung announced in October 2014 it had achieved speeds of 7.5Gbps, the fastest-ever 5G data transmission rate in a stationary environment. It also achieved a stable connection at 1.2Gbps in a vehicle travelling at over 100km/h.

When will I be able to get 5G?

The first 5G handsets could arrive as early as 2017

Speaking exclusively to Cable.co.uk, Huawei, the world’s largest telecoms equipment maker, said that the first 5G smartphones are set to appear in 2017.

The Chinese telecoms giant said the focus for mobile companies would shift away from 4G over the next two years.

“4G LTE is definitely a big thing for us and we’re working with some of the big adopters for 5G as well,” said Huawei Device USA’s training manager Jack Borg, talking to Cable.co.uk at International CES.

5G on the horizon

“Carriers are taking the current 4G we have and they’re giving it some boost and they’re adding to it and changing it. Liberty Global, Verizon and AT&T have all done that recently in different markets in the US.

“So I think we’re going to see that and ride that for a while but then 5G will definitely be on the horizon. I would say probably in the next year-and-a-half to two years.”

Huawei plans to build a 5G mobile network for the FIFA World Cup in 2018 alongside Russian mobile operator Megafon. The trials will run across the 11 cities that will be hosting matches and will serve fans as well as providing a platform for devices to connect to each other.

SK Telecom has teamed up with Nokia to build a 5G test bed at its R&D centre in Bundang, South Korea. They hope to launch a 5G network in 2018 and commercialise it by 2020.

The past: the birth of mobile internet

The first 5G smartphones could arrive as early as 2017

50 billion devices connected to 5G by 2020

Speaking to Cable.co.uk, Ericsson has said that by 2020, 5G networks are going to be serving 50 billion connected devices around the world.

“The technology has to handle a thousand times more volume than what we have today,” Ramneek Bali said.

“We are looking at handling more capacity in 5G because we’re seeing more and more devices will be connected.

“It’s exciting, it’s a platform we are going to provide to everyone to basically connect everything, anywhere. That’s the vision we have for 5G.”

Will 5G come to the UK before other countries?

The general consensus seems to be that the UK is still a few years away from introducing 5G networks to any greater extent than an initially testing/prototypical one.

O2 told Cable.co.uk that “some countries have earlier demands and industrial policies that may lead to earlier adoption of 5G”, even though the UK is playing a leading role in the development of the technology, including at the University of Surrey’s 5GIC.

5G test network

The innovation centre is expected to provide a 5G test network to the university campus by the beginning of 2018, and London mayor Boris Johnson has promised to bring 5G connectivity to the capital by 2020.

Will 5G replace 3G and 4G?

5G promises a seamless network experience undeliverable by current tech

It has taken a number of years for 3G networks to get anywhere near to 100% coverage and the UK’s 4G coverage varies considerably depending on the operator, but is generally limited to the big cities.

Bruce Girdlestone, senior businesses development manager at Virgin Media Business, told Cable.co.uk that 5G is one of a number of technologies that together should be able to provide a “seamless” experience to consumers.

“I think what will happen is small cells, 4G and 5G, and wi-fi will improve and it will become much more seamless to the end user.

The past: the birth of mobile internet

Mobile phones will roam seamlessly between wi-fi and cellular services

Customers won’t know what service they are using

“So they will just consume data over the spectrum and they won’t even know whether it’s over wi-fi or cellular services.

“With that and with 4G and then ultimately 5G from like 2020 going forwards you’ll start to see much more seamless service and much more data being consumed which will then need to be ported on our fibre network.

“It’s going to be a very interesting three or four years as we see how these different technologies develop and overlap with each other as people start to roll these networks out.”

Conclusion

The development of 5G is at such an early stage that the standards by which it is measured are yet to be agreed. What we do know is that it will be fast. Very fast. So fast that many will ask why you would ever need such a fast data speed on a mobile network. They could be missing the point slightly.

The continued rollout of 4G should cater for most of our current mobile broadband needs. But as we’ve seen with other advances in technology, having the ability to do more increases our expectations and before we know it, things that once seemed like science fiction become ‘the norm’. As our expectations increase we put more strain on the networks underpinning this technology.

We can’t predict what demands we will be placing on mobile networks in 10 or 20 years’ time but the idea behind 5G is that it will be fast enough and reliable enough to cope with whatever we can throw at it, that it will feel like a network with infinite capacity – that is why the 5GIC has been given millions of pounds of public money to research it and why companies like Ericsson and Huawei are investing huge sums in the technology.

The first 5G networks should start appearing over the next few years and if they really do deliver a user experience that is effectively limitless, we may find ourselves asking if there will be a need for 6G.

Source: https://www.cable.co.uk/features/news-5g-round-up-everything-you-need-to-know

Laying the foundations for 5G mobile

23 Jan

5g mobile hologram

So-called ‘5G’ mobile communications will use a very high frequency part of the spectrum above 6 GHz. This could support a variety of new uses including holographic projections and 3D medical imaging, with the potential to support very high demand users in busy areas, such as city centres. 5G mobile is expected to deliver extremely fast data speeds – perhaps 10 to 50 Gbit/s – compared with today’s average 4G download speed of 15 Mbit/s. 5G services are likely to use large blocks of spectrum to achieve these speeds, which are difficult to find at lower frequencies.

The timeframe for the launch of 5G services is uncertain, although commercial applications could emerge by 2020, subject to research and development and international agreements for aligning frequency bands. Ofcom says it is important to do the groundwork now, to understand how these frequencies might be used to serve citizens and consumers in the future. The regulator is therefore asking industry to help plan for the spectrum and bandwidth requirements of 5G.

The spectrum above 6 GHz currently supports various uses – from scientific research, to satellite broadcasting and weather monitoring. One of Ofcom’s core roles is to manage the limited supply of spectrum, taking into account the current and future demands to allow these different services to exist alongside each other.

 

1g 2g 3g 4g 5g mobile technology timeline

 

Steve Unger, Ofcom’s Acting Chief Executive: “We want the UK to be a leader in the next generation of wireless communications. Working with industry, we want to lay the foundations for the UK’s next generation of wireless communications.

“5G must deliver a further step change in the capacity of wireless networks – over and above that currently being delivered by 4G. No network has infinite capacity, but we need to move closer to the ideal of there always being sufficient capacity to meet consumers’ needs.”

Philip Marnick, Ofcom Spectrum Group Director, comments: “We want to explore how high frequency spectrum could potentially offer significant capacity for extremely fast 5G mobile data. This could pave the way for innovative new mobile services for UK consumers and businesses.”

These innovations, according to Ofcom, might include real-time holographic technologies, allowing relatives to virtually attend family gatherings. Or they could enable specialist surgeons to oversee hospital operations while located on the other side of the world, using 3D medical imaging.

Ofcom is seeking views on the use of spectrum above 6 GHz that might be suitable for future mobile communication services. The closing date for responses is 27th February 2015.

Source: http://www.futuretimeline.net/blog/computers-internet-blog.htm#.VMJtOv5wtcQ

 

Transmit Signal Leakage in LTE Frequency-Division Duplexing Applications

13 Feb

In today’s high-speed wireless communication standards like LTE, the performance of both base transceiver stations (BTS) and user equipment (UE) transceivers is crucial. LTE supports time-division duplexing (TDD) as well as frequency-division duplexing (FDD). In this post, we look at transmit signal leakage problems that can occur in FDD applications. To do so, we show a numerical analysis using specifications from the Nutaq Radio420X and the standard LTE performance requirements.

Frequency-division duplexing and isolation

FDD implies that the transmitter and receiver operate at different carrier frequencies, allowing for constant and simultaneous transmission and reception. In full-duplex FDD mode, the transmitter signal leakage must be taken into account (this does not apply to TDD or half-duplex modes). The receiver is constantly exposed to this transmit signal leakage and its sensitivity can drop drastically if improper isolation is used. Most of the isolation is obtained with a good PCB layout and shielding, but one will always have to use effective filters/duplexers in order to achieve optimal isolation.

The Radio420X’s receiver has a software-selectable band-pass filter bank. Its filters typically have 40 dB of rejection on either side of the bandwidth. Figure 1 shows a simplified block diagram of the Radio420X transceiver section.

Figure 1 - Simplified Radio420X transceiver block diagram

Figure 1 – Simplified Radio420X transceiver block diagram

Transmit signal leakage

Clearly, the fundamental components of the transmit signal can interfere with the received signal, but this is not the only concern. The transmit signal will also generate out-of-band phase noise that falls within the receiver band. This unwanted power affects the receiver sensitivity by raising its noise floor, as shown in Figure 2.

Figure 2 - Out-of-band phase noise effects on sensitivity

Figure 2 – Out-of-band phase noise effects on sensitivity

Example calculations

Let’s look at a numerical example using the LTE Band 1. It operates within the following frequencies:

  • Uplink (UE transmit): 1920 – 1980 MHz
  • Downlink (UE receive): 2110 – 2170 MHz

Assume that we want to operate in full-duplex FDD using carrier frequencies 1920 and 2110 MHz for a UE transceiver. The Radio420X’s specifications will be used in the following calculations.

First, we determinate how much power will be leaking into the Rx path when operating at the maximum output power. We know that the fundamental Tx component will be filtered out by 40 dB when it reaches the band-pass filter. However, the first variable amplifier of the Rx chain is placed before the filter and is set to a maximum gain of +18 dB for best sensitivity. Its OP1dB is 20 dBm, so any input signal greater than 2dBm will saturate this amplifier and block the whole receiving process. Thus, we need a minimum of 16 dB Tx/Rx isolation to avoid this situation. Knowing that the PCB traces isolation is better than 55 dB, the only worry is about antenna isolation (the Radio420X uses two antennas instead of a duplexer). At 1960 MHz, 30 dB antenna isolation is achieved with a horizontal separation distance of 12 cm (for a -5 dB gain in the direction of the other antenna), or a vertical separation of 17 cm [1], which is easily realized.

The second concern about transmit signal leakage is its out-of-band phase noise. This power can enter the Rx band and affect its sensitivity. The Radio420X shows a typical phase noise of -140 dBm/Hz at a 20 MHz offset with a 2000 MHz carrier, measured with 0 dBm of output power. Assuming that the phase noise remains constant at greater offsets, -122 dBm/Hz (for 18 dBm of output power) of the transmitted signal noise spectral power density reaches the Rx band. The receiver sensitivity, -103 dBm, is measured within a 200 kHz bandwidth with a 5 dB signal-to-noise ratio (SNR). In order to allow the transmitter to affect sensitivity by no more than 0.5 dB, the transmitter noise power needs to be 9 dB below the noise floor, which correspond to -117 dBm. The corresponding phase noise power for a maximum power output of +18 dBm is -69 dBm (-122dBm/Hz + 10log(200kHz)), which is within the LTE specification of -50 dBm for maximum emission from the UE transmitter in its own receive band.

Finally, to get to the -117 dBm target, we need to isolate the antennas by 48 dB. This can be performed easily with an external low-cost ceramic duplexer. However, for a dual separate TX-RX antenna setup, this requires a horizontal and vertical spacing of about 68 cm and 41 cm respectively [1]. Keep in mind that these requirements only have to be met when the transmitter is set to maximum output power in order to not affect the receiver sensitivity.

Conclusion

The worked-out example shows that the main concern regarding transmit signal leakage, in typical conditions, is the transmitter phase noise. The out-of-band noise power will enter into the receiver band and affect the whole Rx path, degrading its sensitivity. This demonstrates how different specifications can critically interact with each other. In order to meet today’s wireless communication standards, transceivers such as the Nutaq Radio420X must have flawless performance for each parameter.

References

[1] International Telecommunication Union. Isolation between antennas of IMT base stations in the land mobile service.http://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-M.2244-2011-PDF-E.pdf

 

Source: http://nutaq.com/en/blog/transmit-signal-leakage-lte-frequency-division-duplexing-applications

Sprint intros first phones to tap its trio of 4G LTE network frequencies

31 Oct
Sprint LTE logo

SUMMARY:Sprint is turning a spectrum disadvantage into a strength with Spark, the carriers solution to optimize bandwidth between its three different LTE network bands. The first phones to use Spark are launching on November 8.

Sprint will have three smartphones on sale November 8 that can support all three of the its 4G LTE frequencies, with a fourth smartphone coming soon. The company is calling its technology Sprint Spark, and it’s the solution for Sprint’s relatively disjointed LTE implementation. All Spark phones will be able to seamlessly move among the 800 MHz, 1.9 GHz and 2.5 GHz frequency bands dynamically as needed based on activity and if coverage allows.

Sprint Galaxy Mega

To get Spark moving, Sprint will sell the $199 Samsung Galaxy Mega, $99 Samsung Galaxy S 4 mini and $199 LG G2 next week (those prices are with-contract — each can be had in lieu of a monthly fee through the Sprint One Up program as well). Right out of the gate, the two Samsung phones will have tri-band support soon after launch with a software update. The LG G2 will get its tri-band functionality in early 2014. And Sprint says the HTC One Max will also be part of Spark and is “coming soon.”

Spark is an effective way for Sprint to manage speeds on its LTE networks. When Spark-compatible phones are sipping data for Twitter or email retrieval, they can use one of Sprint’s lower-bandwidth LTE networks. But if a customer fires up Netflix and needs faster LTE speeds, the handset can tap into a its forthcoming high-capacity 2500 MHz network for more throughput.

Why does Sprint need to do this at all? Because it backed WiMAX as a next-generation technology while its peers decided to wait on LTE. As a result of that and spectrum auctions, AT&T and Verizon got the lion’s share of the lower frequency “beachfront” spectrum for their respective LTE networks.

T-Mobile has had to refarm existing spectrum for its LTE implementation and Sprint is doing the same. But by doing so and being late to the LTE game, the operator has three LTE frequencies to manage, which requires a solution such as Spark. I’m be curious to see how well the technology fares, as the higher frequencies won’t work as well indoors when compared to the 800 MHz band. The 2.5 GHz network launched in five cities today, and once it goes national Sprint will have a solid LTE offering thanks to Spark and the spectrum Sprint picked up from Clearwire.

Source: http://gigaom.com/2013/10/30/sprint-intros-first-phones-to-tap-its-trio-of-4g-lte-network-frequencies/

Synchronization Signals in LTE Downlink

23 Sep

What are synchronization signals? Why do we need them? How are they and where are they transmitted in LTE? The below article should explain the same. Basically, as the name suggests the synchronization signals are needed for a UE which is trying to enter the network to get synchronized to the eNodeB or even for a UE to maintain its already gained synchronization. There are two synchronization signal in LTE downlink, Primary synchronization signal (PSS) and Secondary synchronization signal (SSS), below you find more details about these signals,

Primary Synchronization Signal (PSS)

PSS Generation

PSS is a zadoff-Chu sequence of length 62, whose root index is chosen based on the NID2 value, which is got from the physical cell ID. There can be three different NID2 values (0, 1, 2), hence there are 3 different root indexes (25, 29, 34) corresponding to the NID2 values. The length of the PSS is 72 subcarriers or 6 resource blocks, out of 72 only 62 subcarriers are having valid PSS data, remaining 10 subcarriers (5 on each side) are zero padded.

PSS Resource Mapping

The PSS is always mapped to the central 72 subcarriers, this is to assist the UE to decode the PSS irrespective of knowing the system bandwidth. The central 72 subcarriers may not always align with the resource block boundary, it can always exist in half RBs also. For Eg: In case of 5 MHz the central 6 RBs do not exactly align with the center of the bandwidth, hence the PSS mapping is done as, first 6 subcarriers in second half of RB9, next 60 subcarriers to RB10 to RB14 and remaining 6 subcarriers in first half of RB15.  The PSS is always mapped in last symbol of first slot in subframe 0 and 5, when it is a FDD system and in 3 symbol of first slot in subframe 1 and 6, when it is a TDD system

Since PSS is a Zadoff-Chu sequence, when plotted as a constellation diagram we should see a circle

Secondary Synchronization Signal (SSS)

SSS Generation

The SSS is a combination of 2 31 length binary sequence, where these binary sequences are function of NID1, there can be 168 different NID1 values, hence there are 168 different binary sequence corresponding to these NID1. Also these sequences differ between subframe 0 and subframe 5, infact this the way UE gets the subframe number within the radio frame. These binary sequences are also scrambled with a scrambling sequence which is function of NID2, hence creating a coupling between PSS & SSS.

SSS Mapping

The SSS is also mapped similar to PSS in the frequency domain, occupying the central 72 subcarrier, with 62 valid SSS subcarriers. But SSS is mapped to the last but one symbol of first slot in subframe 0 and 5 for FDD and last symbol of second slot of subframe 0 & 5 in a TDD system. Since SSS is a binary sequence, when plotted we should see two dots on the x-axis.

The symbol location of PSS/SSS in time domain is different between a FDD and TDD system as this helps the UE to identify, if this is a FDD or a TDD system.

Since the location of PSS/SSS is always fixed in frequency domain, the UE can easily do a correlation at the expected band to get the PSS/SSS, from which the UE can aquire many parameters such as the physical cell ID (From NID1 & NID2), duplexing mode( from the location of PSS/SSS in time domain), subframe number( from the SSS sequence), slot boundary as well.

For a new UE, the PSS/SSS helps to get synchronized to the eNodeB and for a idle UE within the service of eNodeB, the PSS/SSS helps to maintain the synchronization. Hence these synchronization signals play a very important role in LTE.

Source: http://ltebasics.wordpress.com/2013/09/23/synchronization-signals-in-lte-downlink/

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