Posts Tagged ‘3G’

Wireless Case Studies: Cellular Repeater and DAS

Friday, February 7th, 2014

Gyver Networks recently designed and installed a cellular bi-directional amplifier (BDA) and distributed antenna system (DAS) for an internationally renowned preparatory and boarding school in Massachusetts.

BDA Challenge: Faculty, students, and visitors were unable to access any cellular voice or data services at one of this historic campus’ sports complexes; 3G and 4G cellular reception at the suburban Boston location were virtually nonexistent.

Of particular concern to the school was the fact that the safety of its student-athletes would be jeopardized in the event of a serious injury, with precious minutes lost as faculty were forced to scramble to find the nearest landline – or leave the building altogether in search of cellular signal – to contact first responders.

Additionally, since internal communications between management and facilities personnel around the campus took place via mobile phone, lack of cellular signal at the sports complex required staff to physically leave the site just to find adequate reception.

Resolution: Gyver Networks engineers performed a cellular site survey of selected carriers throughout the complex to acquire a precise snapshot of the RF environment. After selecting the optimal donor tower signal for each cell carrier, Gyver then engineered and installed a distributed antenna system (DAS) to retransmit the amplified signal put out by the bi-directional amplifier (BDA) inside the building.

The high-gain, dual-band BDA chosen for the system offered scalability across selected cellular and PCS bands, as well as the flexibility to reconfigure band settings on an as-needed basis, providing enhancement capabilities for all major carriers now and in the future.

Every objective set forth by the school’s IT department has been satisfied with the deployment of this cellular repeater and DAS: All areas of the athletic complex now enjoy full 3G and 4G voice and data connectivity; safety and liability concerns have been mitigated; and campus personnel are able to maintain mobile communications regardless of where they are in the complex.

TD-LTE goes mainstream with a new performance promise

Friday, March 1st, 2013

China Mobile’s budding network is helping to pique interest in a different way of using scarce spectrum

A version of LTE that could give consumers more mobile bandwidth for downloading content or apps is moving from the margins to the mainstream at Mobile World Congress this week.

TD (Time-Division) LTE, which uses a single block of radio frequencies instead of the paired blocks used in typical FDD (Frequency-Division Duplexing) cellular networks, has shown up in many places at the world’s annual mobile gathering. Numerous carriers and vendors are building the technology into their gear and demonstrating uses for it, in a departure from the scant attention given TD-LTE a few years ago.

The big prize that shines over all this activity is the prospect of China Mobile’s planned national deployment of TD-LTE, which is still waiting on the Chinese government’s spectrum allocation but is already gathering steam with trial services in six cities. Yet carriers elsewhere are also using or planning to use TD-LTE, including Softbank in Japan, Sprint Nextel and Clearwire in the U.S., and operators in Brazil, Russia, India, Sweden, Saudi Arabia, and other countries. TD spectrum blocks are being set aside in yet other countries, including in a recent auction in the U.K.

“There’s a lot of momentum behind it, and it’s not all China,” said Ovum analyst Daryl Schoolar. Still, with more than 600 million subscribers, China Mobile is big enough to make TD-LTE attractive to network vendors, chip designers and device makers for a long time, he said. “The volume opportunity is going to keep everyone interested.”

At its booth at MWC, China Mobile showed off dozens of chips and devices designed for its planned network. They included smartphones from LG Electronics, Samsung Electronics, Huawei Technologies, ZTE and Quanta; USB dongles and personal hotspots from most of those vendors, and tablets from Huawei and Quanta. The display of chips included ones from big names such as Marvell Technology Group and Qualcomm. All those devices can be used with FDD as well as TD, along with backward compatibility with 2G and 3G networks.

Alcatel-Lucent has already developed a TD-LTE small cell, through subsidiary Alcatel Shanghai Bell, that will be used to add capacity to China Mobile’s network in busy areas. Mindspeed Technologies, which supplied the silicon for it, showed off the cell at MWC.

Also at the show, Nokia Siemens Networks demonstrated a patented algorithm for balancing subscriber loads among LTE cells, including between TD and FDD equipment.

Advocates of TD-LTE say flexibility is its main advantage. Most LTE networks so far have been built with FDD (Frequency-Division Duplexing) technology, which uses two separate and equal-sized spectrum blocks, one for upstream and one for downstream traffic. Because TD-LTE uses just one large block, the frequencies within that block can be divided up in any way that makes sense for the way subscribers will use it.

That means a TD-LTE service could look more like home broadband, with a relatively thin pipe for sending email messages and URLs and a fatter one for downloading the pages that come with those URLs, as well as video, music, images and other content from the Internet.

China Mobile promotes this feature as one of the main things that will make its network better. The carrier could divide its spectrum differently in various areas depending on how the network might be used there, said Lei Cao, a China Mobile representative in the company’s MWC booth.

Some said TD-LTE saves carriers money and is just a better way to use spectrum.

“This is hotly debated, but the TD-LTE advocates will tell you that it can be deployed in cheaper unpaired spectrum and is more efficient when the downlink/uplink is asymmetric,” Tolaga Research analyst Phil Marshall said in an email interview. Dedicating the same amount of spectrum to uplinks as to downlinks leaves a lot of uplink spectrum unused, he said.

The biggest reason FDD is still used is tradition, according to Marshall. When cell phones were used mostly for voice, upstream and downstream traffic was equal.

“Most of the cellular spectrum is allocated in FDD and systems are deployed this way,” Marshall said. “The advocates of FDD will tell you that you get better performance consistency with FDD and it is easier to implement — particularly when coordinated with other FDD systems.”

Without the need for pairing, it’s also easier to cobble together various frequencies. In January, China Mobile and ZTE said they had demonstrated combining two separate TD-LTE spectrum blocks into one virtual block and assigned 75 percent of the whole to downstream traffic.

It’s not especially challenging to implement TD-LTE, Schoolar said. Nor is it hard to hand off subscribers from those networks to LTE FDD systems, according to China Mobile and others. Despite the dominance of FDD, most existing LTE base stations can be set up for TD use with a software upgrade or a new line card, Schoolar said. Sprint plans to mix FDD and TD networks by using the Clearwire TD-LTE network for extra capacity in busy areas, shifting users from one to the other as needed.

China Mobile Hong Kong has already launched a combined TD and FDD network. It puts subscribers on TD-LTE where it’s available, then shifts them onto FDD where possible, and puts them onto GSM when necessary. All these transitions are transparent to users, Lei said.

The pre-commercial network in mainland China is growing rapidly despite the fact that China Mobile can’t offer commercial service yet. There are about 20,000 base stations there today and will be 200,000 in 100 cities by the end of this year, Lei said. And China Mobile is not expected to be the only Chinese carrier to deploy TD-LTE.

That bodes well for a high-volume market that should make TD-LTE devices cheap and plentiful in other parts of the world, with the help of big silicon vendors, analysts said. “It really depends on guys like Qualcomm to make it happen,” Marshall said.

Source:  networkworld.com

Wireless LAN vendors target surging carrier Wi-Fi market

Monday, February 25th, 2013

Ruckus, Aruba products aim at large-scale, integrated Wi-Fi services

Two wireless LAN vendors are targeting the next big explosion in Wi-Fi growth: hotspots and hotzones created by carriers and other services providers.

Both Ruckus Wireless and Aruba Networks this week at the Mobile World Congress Show in Barcelona outlined products aimed at this provider market. The goal is to be part of a crystallizing of hardware and software that can integrate Wi-Fi with core mobile networks.

As part of its reference design for carrier-based Wi-Fi services, Ruckus announced a new family of outdoor 802.11n access points, the ZoneFlex 7782 series. Four models offer different internal and external antenna configuration options. All have three transmit and three receive antennas supporting three data streams for a maximum data rate of 900Mbps. All three have Ruckus’ patented BeamFlex adaptive antenna technology, designed to boost gain and reduce interference. There’s also a GPS receiver, which service providers can leverage for location-based services.

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Deliberately bland in design, the new Ruckus ZoneFlex 7782 outdoor access point aims at high-performance carrier Wi-Fi networks: dual-band, 3-stream 802.11n with a data rate of nearly 1Gbps.

The company also unveiled a Wi-Fi traffic analysis application for carriers, called the SmartCell Insight analytics engine, which runs on Ruckus’ Smartcell 2000 Gateway, which bridges Wi-Fi and cellular networks. The software sifts out a wealth of data about access point usage, bandwidth, subscriber activity and other metrics, and packs them into a data warehouse. Pre-written and custom reports translate the raw data into information about how well the Wi-Fi network is performing. A battery of standard APIs let carriers export the information to existing data-mining tools and interface with core network applications.

Finally, Ruckus announced SmartPoint, which adds to the ZoneFlex 7321-U access point a USB port that can accept a 3G, 4G, or WiMAX external dongle. The idea is to quickly and easily create a wireless backhaul option where a cable isn’t possible (such as a city bus). Ruckus automatically pushes to the access point the needed driver software for specific 3G/4G/WiMAX dongles. KDDI in Japan, with an extensive WiMAX network, can offer shop owners a Ruckus access point for hotspot Wi-Fi, with a WiMAX dongle for easy backhaul to the Internet.

Both the 7782 outdoor access point, priced at $3,000, and Smartpoint, at $400 are available now; the analytics application, with pricing based on the size of the network, will ship in the second quarter.

Aruba’s carrier play

Aruba, too, is recasting its WLAN architecture via software updates to address carrier requirements for creating a high-capacity, secure and reliable Wi-Fi service for mobile subscribers.

Dubbed Aruba HybridControl, the new code gives Aruba’s 7200 Mobility Controller massive scalability. Aruba says the software update will let the 7200 manage over 32,000 hotspots. That translates into over 100,000 individual access points, because each hotspot can have several of the vendor’s Aruba Instant access points. The scaling lowers carriers’ backend capital costs, cuts data center power demand, and needs less rack space, according to Aruba. The Aruba Instant model offloads cellular traffic locally to the Internet, while centralizes selected traffic such as billing and legal intercept via an IPSec connection to the 7200 controllers at the core.

HybridControl offers “zero-touch activation” for factory-default access points, with no need for any manual pre-provisioning. Switched on, these access points interface with the Aruba Activate cloud service to discover the carrier’s configuration management system and download it. Then, the access points use an assigned X.509 certificate to authenticate with an Aruba controller and set up an IPSec tunnel.

The HybridControl architecture leverages existing Aruba features such as:

  • AppRF, to identify and prioritize real-time applications, such as Microsoft Lync, to create different classes of service;
  • ClearPass Policy Management, a server application to authenticate new access points joining the mobile core network.

The carrier-focused HybridControl offering includes several products: the Aruba 7200 Mobility Controller, available now with prices starting at $38,000; Aruba Instant access points, available now with prices starting at about $400; Aruba Activate, available now and free of charge for Aruba customers. The software update for the 7200 will be available as a free Aruba OS upgrade in the second quarter.

Source:  networkworld.com

Ericsson: Cellular data demand doubled annually the last five years – Are you ready for ’13?

Tuesday, February 19th, 2013

Global cellular data traffic has doubled in the past year, according to a report released by Ericsson, attributable in particular to an increase in 4G and LTE devices.

This increased demand for mobile signal is expected to at least double again this year, as it has in each of the past five years (see Ericsson graph above), which begs the question:  Is your facility equipped to deal with the continued surge in cellular signal demand?

Knowledge workers, sales staff, and others have come to rely almost exclusively on cell phones as they spend less and less time at their desks, to say nothing of clients and visitors who expect a reasonable level of mobile connectivity at your site.  Additionally, new workspace philosophies such as activity-based workplaces, mobility centers, hotelling and hot desking will only increase reliance on cellular connectivity.

Yet, even within the same office, hospital or university campus, warehouse or other facility, cellular signal can be drastically different, allowing some users to maintain acceptable mobile voice and data connections while other frustrated users drop calls and apps fail to connect to data sources.  Whether the fault lies with structural interference or inadequate cell network coverage in your area is irrelevant to your end users, as decreased productivity and morale can often result from an inability to communicate as expected.

These problems can be identified and remedied, however, with a cellular repeater/amplifier solution created specifically for your facility by qualified Gyver Networks RF engineers.

Gyver Networks will survey the location to create a complete picture of your RF environment, then engineer and install the optimal system to provide 3G, 4G, and LTE cellular signal to your building or campus, whether you require a DAS (distributed antenna system) or cellular base station.

Ensure that the continued increase in mobile demand doesn’t have a negative impact on your continued growth.  Contact Gyver Networks today for a free consultation.

 

Mobile’s dawning signal crisis

Wednesday, February 13th, 2013

Telecommunications tower (Copyright: SPL)

In April 1973, Marty Cooper made a phone call that put him straight into the history books. As he strolled down Lexington Avenue, New York, the Motorola executive (CK) whipped out an enormous prototype handset that he had built and placed the first public, mobile phone call.

The brief chat – and the photograph that immortalised the moment – marks the start of the mobile phone era. But Cooper’s legacy extends far beyond just that first conversation.

Along with a host of inventions, the engineer also formulated – and lent his name to – a mathematical law that captures the inexorable progress of our communications. Cooper’s Law, as it is known, shows how our use of the ether has grown since Guglielmo Marconi first transmitted radio waves 2.4 kilometres across the streets of Bologna – eight decades ahead of Cooper’s own historic transmission.

It has been estimated that the technology available when Marconi made his first transatlantic transmission, radio techniques were able to support just 50 simultaneous conversations worldwide. Since then radio capacity has grown by a factor of a trillion – doubling every two-and-a-half years. That’s Cooper’s law.

As well as describing progress, the law also become the mobile industry’s ruthless master: providing an aggressive roadmap for the rise of mobile culture.

The industry met this challenge thanks to advances in technology.

But now the game has changed. Although few in the industry acknowledge it publically, Coopers Law, which has stood for more than a century, is broken. And it is all down to the phone in your pocket.

Bin there, sent that

To understand the scale of the problem, you only need to look at the numbers.

For example, the mobile giant Ericsson has been tracking the growth in mobile traffic for years. But 2009 was a landmark year, according to the firm’s Patrik Cerwall: “That year saw more data traffic than voice traffic over the mobile networks”. And the data traffic has been doubling every year since – far outracing Cooper’s law.

The big accelerator was the smartphone, which suddenly made the data-carrying capacity of 3G networks attractive. “People didn’t really understand the benefit of 3G until the app concept changed everything,” Cerwall elaborates.

Data-hungry video is also driving demand. Networking firm Cisco has just reported video downloads last year crossed the 50% threshold, accounting for half of all data transferred over the mobile networks.

At the moment, there are around 1.1 billion smart phones across the world; by 2018 (the horizon for the Ericsson forecasts) that will treble to 3.3 billion. If you think that in 2012, smartphones represented only 18% of total global handsets, but represented 92% of total global traffic, you begin to see the problem.

And the growth will continue relentlessly, according to the Cisco analysis. In 2012, for example, global mobile data traffic grew 70% from 2011, to 885 petabytes per month – that is 885 million gigabytes of data. And in the next five years, it is expected to increase 13-fold, eventually reaching 11.2 exabytes (11, 200 million gigabytes) per month by 2017, according to Cisco.

These dramatic hikes will in part be driven by more people switching to smartphones, particularly in emerging markets, as well as new features on phones and in apps.

The impact of simple changes in an app was dramatically demonstrated in November 2012 when Facebook released new version of its mobile app for Android and Apple phones. Prior to the release, according to networking firm Alactel, the social network already accounted for 10% of the signalling and 15% of the airtime load on 2G/3G networks, respectively. But, as users around the world updated and started to use this new version, the firm noticed a dramatic increase of almost 60% in the signalling load and 25% in the airtime consumed by new features in the app.

However, data hikes will not just be driven by consumers. Firms also predict a rise in so-called machine-to-machine (M2M) communication, that will connect the mobile networks to an array of inanimate objects – from bins that will signal when they are full to electricity meters that will constantly call in to the utility company.

By the end of this year, Cisco predicts that the number of mobile-connected devices will exceed the number of people on earth, and by 2017 there will be more than 10 billion.

No wonder the chairman of the US Federal Communications Commission recently declared: “The clock is ticking on our mobile future.

Running out

The illusion is that the airwaves, like the atmosphere they pass through, are effectively limitless. We can’t see them, they can travel in any direction and link any two points – why should they be limited? Yet, in practice they are as hemmed in as a motorway through a city.

Radio spectrum is a limited resource, strictly farmed out by national and international regulation. At the moment it is all spoken for by the military, mariners, aviation, broadcasters and many more – all the way up to the very extreme of useful frequencies at 300 gigahertz.

No-one can get more bandwidth without someone else losing out. The 4G spectrum auction that recently began in the UK, for example, is the equivalent of adding a new six-lane motorway to the existing wireless infrastructure (itself already running at 10-lanes), built on virtual land vacated by old-fashion TV broadcasts.

It helps, but will only keep the expansion going for a certain time. Which is why mobile operators, and their rivals, are gearing up for major spectrum negotiations at the International Telecommunications Union in 2015. The so-called WRC-2015 conference aims to carve up the available spectrum amongst different competing uses. But an overriding priority is identifying and allocating additional frequencies to mobile services.

Already, the stakeholders are preparing their positions. Ericsson’s Afif Osseiran, project coordinator for the European consortium Metis, says the ITU conference “will be a crucial moment for laying out the spectrum needs for the 2020s.”

But industry will not just rely on these delicate negotiations to secure its future. Much of the advance in the past 20 years has not been about how many of these wireless “lanes” we have, but how efficiently we use them.

Like a newly built motorway that’s used by just a few cars, the first generation of phones were incredibly wasteful of the spectrum they used. Capacity was wasted in the same way as the gaps between vehicles represented lost transport opportunities.

In going from 1G to 2G, there was a 1,000-fold increase in capacity, mostly not because of the new radio lanes added in, but because more traffic was squeezed onto those lanes.

And in going from 2G to 3G, capacity rose another factor of 1,000: digital techniques managed to squeeze out yet more of the empty space.

But with the latest generation of tricks being rolled out in 4G (actually described as 3G Long Term Evolution by developers), the industry is running out of ways to improve the efficiency further.

These limits that determine how much information can be transmitted were established in the 1940s by the American engineer Claude Shannon. Although his employers, the Bell Labs of AT&T telephone, were interested primarily about the limitations of telephone wires, Shannon’s equations can be used equally for radio transmissions.

And mobile experts generally accept that the limits to data flow revealed by Shannon’s formulae are close to being reached.

Data crunch

So how will the mobile industry meet this challenge and keep satisfy out appetite for data?

The industry is clearly optimistic. It already confidently speaks of 5G – a further generation of technology that will roll out as current ideas have run their course. What exactly they mean by 5G is poorly defined, but a host of tricks are being discussed that it’s hoped will keep past trends going well into the next decade.

Which is just as well, as the lure of being immersed in a seamless flow of data will only become more compelling, says Rich Howard, formerly head of wireless research at Bell Labs and now with Winlab at Rutgers University.

“Mature technology is invisible – and that’s the direction we’re heading,” he says.

Howard looks forward to a day when phones begin to make intelligent decisions by themselves.

“What you want is a digital assistant that, while you’re having a call with somebody, will be busy looking at options for actions relevant to that call and have them available,” he says. So, if you are talking about a train journey, the phone could begin to check your calendar, ticket prices and connections. By the time you hang up, it would be able to present you with a list of available options. “Everytime you start to say something, you turn around and it’s already done, the way you want it done.”

It is a vision that is a world away from Cooper’s first call forty years ago and one that is only going to add the coming data crunch.

How the industry plans to keep up and deliver this future will be explored in the next article in this series.

Source:  BBC