Not a long time ago, in a galaxy not far away – in fact this one – small cells made their first appearance on the scene. In a 3G network, small cells were primarily used for in building coverage where it was needed. It was an important role, but not a glamorous one.
So what awakening in the force is calling for a return of the small cells now? First, the demand for mobile data took over the world, leaving operators with overloaded networks and scrambling to add both coverage and capacity. Rolling out LTE networks for mobile traffic was the first step, but these networks are already being strained.
Strategy Analytics predicted in its report, Mobile Data Traffic Forecasts 2014-2018,that by 2018 mobile networks will carry 56.2 Exabytes of data, up from 21.3 Exabytes of mobile data traffic in 2014. This growth in traffic is being driven by both strong performance on 4G/LTE networks and rapid growth in smartphone data subscriptions, with future growth driven by tablets, consumer electronics and M2M devices contributing to a larger share of the total data traffic.
There are a number of ways that operators can add capacity to their networks, including acquiring new spectrum, which leads us to our second point – LTE spectrum is both scarce and expensive. Mobile operators are turning to a Heterogeneous Network model – or HetNet – to maximize their spectrum. A HetNet is composed of a combination of macrocells, Wi-Fi, distributed antenna systems (DAS) and small cells. By using a layered network model with deployed small cells, mobile operators not only address coverage concerns between macrocells and in indoor environments, they can also add much needed capacity to the network and improve the overall end user experience.
The addition of small cells to the mobile network adds complexity when it comes to RF network planning as compared to a macrocell-only network; therefore, efficient and autonomous coordination between macrocells and small cells is key. Self-organizing Networks (SON) techniques provide the real-time self-configuration, self-optimization and self-healing capabilities that are becoming mandatory features for the HetNet to work as a cohesive network. SON offers the promise of reducing costs in initial rollouts, enabling more effective coordination of time and frequency resources, providing dynamic interference management, and adapting to changing network conditions.
Mobile operators are deploying LTE-Advanced capabilities such as carrier aggregation and interference management techniques to make their networks even more efficient. Here again, small cells remain critical to operators’ overall strategy as they provide additional capacity in dense indoor environments where a majority of data traffic will be generated.
In a HetNet scenario combining small cells with Wi-Fi and macrocells, mobile operators are rolling out a number of interference management techniques to ensure the network is optimized for capacity and coverage.
Mobile operators are currently focused primarily on deploying eICIC and MIMO. Relay nodes add additional complexity to the network and will be rolled out at a later date.
Carrier aggregation aggregates mobile operators’ 3G spectrum freed up by LTE roll-outs along with LTE and LTE-Advanced spectrum to add increased throughput to the network. The scarcity of spectrum has led to faster adoption of carrier aggregation by mobile operators as compared to other LTE-Advanced capabilities. Carrier aggregation is also being used for both LTE-FDD and LTE-TDD modes, allowing mobile operators with both network assets to adopt the technology to gain even more performance.
One of the biggest innovations in driving the return of the small cells is LTE-Unlicensed technology, also known as LTE-LAA (LTE-License Assisted Access). Mobile operators are beginning to aggregate unlicensed spectrum in the 5 GHz band with their available licensed spectrum to add even more bandwidth.
As LTE-LAA is an extension of LTE-Advanced and is based on carrier aggregation, it’s no surprise that small cells remain central to its deployment. Leveraging small cells for LTE-LAA provides a localized approach to carrier aggregation that helps mobile operators co-exist with the Wi-Fi community, while being able to further maximize their spectrum to increase capacity and coverage and ease network strain. Small cells are also suited to deployment in the LTE-LAA 5 GHz band as they are better suited to the band’s low power requirements as opposed to macrocells.
LTE-LAA is expected to be fully standardized in 3GPP Release 13, currently planned to be finalized in 2016.
Dell’Oro Group has forecast that small cell RAN revenues will account for 16% of the total RAN market by 2020. According to Pongratz, “the indoor enterprise/public access market improved significantly in 2015, though outdoor revenues still account for the greatest portion of revenue. We expect the indoor segment to grow at a quicker pace and expect the revenue split between indoor and outdoor to be closer to 50/50 by 2020.” And 5G small cells will account for close to 5% of the small cell market by 2020.
A large proportion of the world’s small cells have been deployed in Asia Pacific in Korea and Japan, with volumes picking up in China and India. In dense environments, mobile operators are deploying enterprise and residential small cells in indoor venues to add capacity locally, with the potential for a 1-to-4 ratio of macrocells to small cells.
Outdoor picocells will most likely leverage a Cloud-RAN architecture and will roll out in 2017. Cloud-RAN deployments are now out of the proof of concept stage and are currently in trials. These cloud-based access points, which are also known as virtual base stations or C-RANs, will form the base of a 5G network architecture. They will handle not only the voice and data traffic for consumers, but will also support the M2M and IoT applications that form the ‘connected network’ of the future.
The majority of small cells will be multi-mode, supporting both LTE and Wi-Fi in the 5GHz band, allowing operators to take advantage of cost savings due to leveraging unlicensed spectrum. By supporting the 5GHz band, mobile operators can also deploy LTE-LAA on the same small cell.
Each small cell deployment is unique – and what happens in the lab is never replicated exactly in the field. In addition, we learned that focusing on data speeds in trials wasn’t enough. In real-world deployments, it’s more important to make sure that the small cells gel with the network from all angles and not just provide the required data speeds.
Mobile operators also need to plan for more than just mitigating interference between small cells and macrocells. They also need to mitigate issues associated with small cell placement and acquiring the necessary real estate. This needs to happen early in the planning process to ensure a smooth roll-out.
Small cells have returned in a big way. From a role of just filling coverage gaps in 3G networks, small cells now form a major part of mobile operators’ strategy as they contend with exploding mobile data traffic on their networks and chart their path towards 5G. It’s all about adding capacity efficiently and economically. Now that the small cell force has awakened, we can’t wait for the next sequel.
Earlier this week, Texas Instruments announced two new SoCs (System-on-Chips) for the small-cell base-station market, adding an ARM A8 core while scaling down the architecture of the TCI6618, which they had announced for the high-end base-station market at MWC (Mobile World Congress).
|Cognitive radios will be enable spectrum re-use
in both the frequency and time domains. (source – Mindspeed)
While 4G networks are still just emerging, Johnston went on to boldly describe the attributes of future 5G networks – self-organizing architectures enabled by software-defined cognitive radios. Service providers don’t like the multiple frequency bands that make up today’s networks, he said, because there are too many frequencies dedicated to too many different things. As he described it, 5G will be based on spectrum sharing, a change from separate spectrum assignments with a variety of fixed radios, to software-defined selectable radios with selectable spectrum avoidance.
|Software-defined cognitive radios will enable dynamic spectrum sharing,
including the use of “white spaces” (source Mindspeed)
Touching on the topic of “white spaces“, Johnston said that the next step will involve moving to dynamic intelligent spectral avoidance, what he called “The Holy Grail”, with the ability to re-use spectrum across both frequency and time domains, and to dynamically avoid interference.
|Mindspeed’s Transcede 4000 contains 10 MAP cores, 10 CEVA x1641 DSP cores, and 6 ARM A9 cores, in a 40nm 800M transistor SoC (source Mindspeed)|
The Transcede 4000 contains 10 MAP (Mindspeed application processors) cores, 10 CEVA x1641 DSP cores, and the 6 ARM A9 cores – in dual and quad configurations. Designers can use the Transcede on-chip network to scale up to networks of multiple SoCs, in order to construct larger base-stations. How far apart you can place the SoCs depends on what type of I/O (input-output) transceivers you use. With optical fiber transceivers, the multicore processors can be kilometers apart (see Will 4G wireless networks move basestations to the cloud? ) to share resources for optimization across the network. The dual core ARM-A9 processor in the Transcede 4000 has an embedded real time dispatcher that assigns tasks to the chip’s 10 SPUs (signal processing units), which consist of the combination of a CEVA X1641 DSP and MAP core. To build a base-station with multiple Transcedes, designers can assign one device’s dual core as the master dispatcher to manage the other networked processors.
The evolution of software complexity is also a challenge, with complexity increasing 200X from the less than 10,000 lines of code in the days of dial-up modems, to 20M lines of code to perform 4G LTE baseband functions. Software engineers must support multiple legacy 2G and 3G standards in 4G eNodeB base-stations, in order to enable migration and multi-mode hardware re-use. Since the C-programming language does not directly support parallelism, Mindspeed takes the C-threads and decomposes them to fit within the multicore architecture, says Johnston.
The Opensource concept has been highly successful in many areas of software. This website, as do the majority of the web, runs on MySQL and Linux – both developed by volunteers from around the world. Source code is published and can be used by anyone, on the basis that any improvements made are also shared with the community. Most of the successful projects have a commercial business co-ordinator that is funded by providing support and/or more robust/complete for those organisations that want to pay for it. Well supported crowd-sourced developments can achieve high levels of functionality, security and maturity because they’ve been stretched, scrutinised and tested in many different ways. Smaller projects that haven’t attracted critical mass can fall by the wayside leaving poor quality or incomplete designs.
Opensource also applies to other fields, and includes hardware, media (photos, videos etc.). Popular opensource licence agreements, such as GNU and Creative Commons encourage sharing by making it clear what the author intends.
This doesn’t avoid the issue of patents and Intellectual Property Rights – there are many involved in all aspects of mobile networks, embedded in the standards. Many of the original GSM patents have expired since the system was originally developed more than 20 years ago. Others still apply.
There are several Opensource projects working towards a complete mobile network, including both the hardware and software, compatible with today’s standard mobile phones.
OpenBTS is the most successful, with quite a mature and stable solution for GSM with 3G UMTS released in October 2014. It builds on Asterisk, an opensource voice switch used in many PBX and Internet VoIP services, extending it with the GSM protocols. It’s managed by Range Networks who own the trademark and strongly supported by others including Fairwaves.
Osmocom appears to be more research lab oriented including GSM alongside other radio technologies, such as DECT and TETRA. Core network is GPRS but there is no voice switch in scope.
YateBTS was recently started by one of the founders of OpenBTS. It has a long term vision to create a unified core network using VoLTE for calls for both 2G and 4G, and substantially reducing bandwidth for voice over satellite links compared to traditional SIP. The project is co-ordinated by Romanian company Legba.
OpenLTE is relatively new project to implement the core 3GPP LTE specifications. Today, code is available for test and simulation of downlink transmit and receive functionality and uplink PRACH transmit and receive functionality. This is very much research lab oriented and nowhere near ready for field use. Three other LTE opensource projects are also at early stages as described here.
These projects all benefit from and build on other Opensource projects, such as OpenSS7, Asterisk, GNURadio etc.
Although not nearly as extensive as a standard commercial product, these can be feasible for basic use with isolated service. Mobility, handover and roaming capabilities are included as are voice, SMS and data services. Looking a bit deeper, each cell/sector is configured as a completely separate Location Area so a full location area update is used to handover between cells. GPRS supports only two of the four coding schemes; manual configuration is required of many parameters, such as neighbour lists, timeslot allocation, RF power levels. In my view, this would hamper anything other than a small scale deployment.
The system can be connected to wholesale VoIP, SMS and Internet connections to provide inbound and outbound voice and data. One complication is that because different suppliers are typically used to provide wholesale voice and text services, each would require a different MSISDN (phone number) – definitely confusing for end users.
GPRS data does work but isn’t as fast or mature as a commercial EDGE implementation. One company doesn’t recommend using it at all, reasoning that Wi-Fi is cheaper/better in such low price markets for data only. However VoIP over Wi-Fi is considered far less attractive than GSM for voice.
The system can use existing SIM cards from an existing network, assigning a local number and automatically registering them for use. The full GSM security can’t be used in this case (because the encryption key is hidden inside the SIM card), but a simpler form of encryption is offered.
Today, it’s possible to program your own SIM cards manually. For larger quantities, a full production run can be bought with your own logo design using your own specified parameters.
Several vendors offer all you need to run a basic GSM service, including the core network, with off-the-shelf hardware for use in the lab or outdoors.
Just don’t expect a fully automated SON solution that sits comfortably with any existing network on the same frequencies – you’d still need a commercially mature small cell solution for that. You’ll also need some spectrum to use this legally, either a test licence for your lab or a fully blown one from the regulator. In a few countries, low power GSM is legally permitted in certain guard bands (eg at 1800MHz) without a licence.
Example products include:
An example installation described here is of a remote Mexican village of 700 inhabitants 5 hour away from the nearest city. It has a simple network with two GSM transceivers that handle around 1000 voice calls and 4000 texts in a typical day. The antenna mast is constructed from a 6 metre bamboo pole. Another Mexican village of 500, San Juan Yaee, was connected for just $8,000 – about 15% of the cost quoted by the national operator – with ongoing monthly rates of $2. At those prices, nobody’s going to get rich.
Software definable radio hardware can be used for a wide variety of different applications, ranging from detecting/decoding shipping and aircraft location beacons. This article outlines 10 different possibilities.
One application which I though remarkably innovative was used to locate stranded hillwalkers from a helicopter. The GSM basestation onboard takes several measurements of the walker’s phone signal from different positions and triangulates to find where they are. Using simple GSM time-advance measurements, the results are displayed on an iPad inside the helicopter. It’s not dependent on mobile data or the victim being conscious, as is needed for a similar app called SARLOC.
I’m enthusiastic about the use of Opensource projects to stimulate research and development into new pioneering new ways and means of improving and extending mobile technology. It should enable our academic institutions to demonstrate and prove their theories with limited budgets.
There may also be an opportunity to connect some of the most remote and unserved communities which commercial organisations haven’t been able to reach. The scale of this would be limited by spectrum licences and IPR. The recent proposal by Mexican regulators to allocate some 850MHz spectrum for community use by unserved areas Mexico sends a signal to commercial operators that they can’t simply ignore this demand.
In most cases, I believe it would be better to use commercially mature, mass market solutions managed by professional organisations. Only where those needs are not being served, and regulators support and encourage it, would we see this self-driven community driven approach adopted more widely. The lack of scalability and management features of these solutions limits their scope to very small and simple deployments. Commercial ventures could either develop their own products using proven software from companies such as Radisys or NodeH, or adapt and extend many of the existing proven small cell products already on the market (look in our vendor section for plenty of ideas!)
It’s been estimated that the volume of global monthly mobile data traffic will exceed 15 exabytes by 2018. LTE is already proving to be a major bandwidth hog. While 4G represents only a fraction of mobile connections today, it accounts for at least 30% of mobile data traffic, thanks to a surge in high-bandwidth content such as video calling and music streaming.
Yet, the growth in bandwidth demand is not only about smartphones, tablets and other mobile computing gadgets. The sales of these devices are set to reach 2.4 billion units this year, but other types of connected ‘things’ will require their share of the already stretched networks too. Industry analysts have estimated that the number of wireless connected things will exceed 16 billion in 2014, up 20% from the year before. This growth is set to continue as the Internet of Things gathers pace, with more than double the number of connected devices – 40.9 billion – forecasted for 2020.
As existing 3G and 4G networks struggle to cope with the influx in data traffic, mobile operators are looking at solutions to offload traffic from their current base station networks. Small cells will be their solution of choice – so the number of small cells networks deployed across Europe is going to increase dramatically over the next few years. Small cells that are connected to city-wide superfast fibre networks will be the most economic and scalable way of ensuring that the needs of mobile users for more and more bandwidth are met in the future. Small cells will also be an enabler for the Internet of Things, paving the way for more connections than ever before.
Shortcomings of rooftop base stations
Today’s badly congested 3G and 4G networks rely on rooftop base stations. Many operators have been scrambling to acquire enough rooftop space for LTE, but still 4G networks don’t often meet their bandwidth hungry customers’ expectations, especially in dense urban areas such as pedestrian zones. While filling rooftops with base stations might have been a good solution for 3G, in the LTE era, the cells are becoming smaller, and mobile operators need ten times more base stations to cover the same footprint of a city.
Imagine a situation today where you have five people waiting for a bus, all with a brand new 150 mbps iPhone 6. The existing rooftop base station infrastructure is not able to cope with the sudden surge in bandwidth demand, as all five try to read the news, order groceries or download a restaurant menu, at the same time.
Recognising the need for faster evolution of mobile networks, the European Commission has committed to investing up to €700 million for the developments of ‘ubiquitous 5G communication systems’. This funding is part of a joint public and private sector initiative that aims to overcome today’s data traffic challenges. The ambitious goals of this 5G initiative include increasing wireless area capacity by a factor of 1,000 compared to 2010, creating a high-bandwidth network with 0% downtime, and enabling the roll-out of very dense wireless networks that are able to connect over 7 trillion devices amongst 7 billion people.
Getting ready for the future
As mobile operators gear themselves up for 5G, many of them realise that they can no longer rely on rooftop base stations. Why would a customer splurge on a 5G contract and a 5G-ready smartphone, if they aren’t able to get superfast download speeds? Instead, they will go to an operator that is able to give them the capacity they crave.
To eliminate the well-known capacity problems with rooftop base stations, future proof their networks and stay competitive, more and more European mobile operators are starting to tap into small cells. They are realising only small cells connected to fibre can bring mobile users the great user experience they expect on their LTE-enabled superfast mobile devices – down at street level where it really matters. When connected to fibre networks, these small cells can collectively deliver up to Gigabytes per second of capacity, making entire cities 5G ready in a cost effective way.
The mobile operator community has been talking about the potential of small cells for a couple of years, but up until recently, the size of the boxes prevented their widespread use. All leading networking vendors have invested in the development of more suitable equipment, so the technology is now ready to allow mobile operators to start planning their roll-outs in earnest.
To be able to roll out faster than their rivals, many European mobile operators are now starting to buy space on lampposts, billboards, bus stops or even public toilets, and equip them with small cells.
Small cells – the only way to 5G
Still in recovery from the substantial investment needed for 4G, some cost-conscious mobile operators might be tempted to tighten the purse strings with small cells to protect their margins.
Yet, they really don’t have a choice but to invest. If they don’t, they will lose customers. It’s as simple as that. Why would a user buy a top of the range LTE-enabled smartphone or smartwatch, if they aren’t able to make the most of its superfast download speeds – unless they are standing on a rooftop? Instead, they will get their device from an operator that is able to give them the capacity they crave.
Other small cells-ready players aren’t the only competitive threat for mobile operators. Street furniture providers might eat into the profits of those mobile operators who drag their heels over small cells too. Through city-wide wifi schemes, street furniture companies are eliminating completely the need for mobile users to use their operator for data in some cases. Why would a mobile user pay a premium for patchy 5G connectivity, if they can get better speeds and coverage with free wifi?
In any way you look at it, 5G will only materialise with small cells connected to existing superfast fibre networks. And all European mobile operators’ competitiveness – and survival – will rely on 5G.
Telecoms professionals have a pretty poor track record of predicting what applications and services will be most popular. For example, 3G had plenty of hype around personal videocalls and M-commerce which have still to come to fruition. 4G certainly provides faster data speeds (especially uplink), but we seem to have forgotten about voice.
Moray Rumney of Agilent (soon to be rebranded Keysight) spoke of the tradeoffs when designing any new generation. Do we want high speed, long battery life, reachability or resilience. It’s tempting to say we want all of those. For sure, the focus in recent releases seems to be mostly around peak data rates and many other benefits have gone out the window. I still find many buildings or locations where I can’t be connected or have poor quality voice/slow or unusable data service. The conference venue itself was a relevant example. Further confirmation can be found in a recent UK OFCOM report based on RootMetrics data which established that 30% of consumers find themselves outside coverage at least once a week.
Looking at it from a performance perspective, you might think:
|Features we’d all like||Consequences
(in no particular order)
|Higher bit rates
Higher capacity density
Higher spectral efficiency
Higher connection density
|Terminal and Network Cost
Terminal battery life
Where others might prefer to focus more on availability and efficiency:
|Features we’d all like||Consequences
(in no particular order)
|High service availability
Lower terminal and network cost
Higher energy efficiency
Longer Batter Life
|Lower or sufficient bit rates
Lower spectral efficiency
Lower capacity density
Lower connection density
The tradeoffs are perhaps best illustrated using a Spider Chart:
This leads to the view that 5G will become more than one technology to serve our needs – perhaps amalgamating one or two that go really fast with one or two that reach the most remote regions. Perhaps it could focus on one (sub)set of requirements and rely on existing technologies to cater for others.
Indeed, as with 3G and 4G before it, we would expect 5G to be able to interwork with previous generations rather than replace them. With Carrier Wi-Fi also emerging strongly, including the new Gigabit 802.11ad short range technology, 5G will have to deliver significant additional benefits to justify heavy further investment and shouldn’t be considered a never-ending gravy train.
One theme we heard many times throughout the event was the need to develop and extend telecoms services into the many vertical market sectors. Perhaps 5G could look to build on and extend the value of fully mobile wireless service differently for each sector.
The theme of M2M (Machine to Machine) comes up a lot in this context, but again it seemed to be all encompassing and widespread. We’re not talking about a specific radio technology here – any and every technology available would be considered. Low power Bluetooth was mentioned more than once.
As an example of one vertical (energy retailers), what I learnt was that (here in the UK) we’re implementing two somewhat contradictory approaches. Our first responders and emergency services, who today use the expensive and outdated European TETRA radio system, will find it replaced by standardised LTE – possibly using different frequencies with a few extra standardised features added in. This will save huge amounts of money and benefit from the mass market of LTE.
At the same time, the UK is installing a completely separate national radio network to communicate with smart energy meters. In the north of the country, Arquiva has a contract to do so and uses their own proprietary system. In the middle and south, Telefonica will simply reuse their existing 2G/3G/4G mobile network which seems to be a lot more practical to me. Extending coverage of the cellular network where needed to reach outlying meters would bring wider benefits of cellular connectivity to those areas overall.
The headline timeframe for 5G is really quite short. Japan (DoCoMo) have made bold assertions that they would have it available for the 2020 Summer Olympics. They’ve even announced their six suppliers for 5G trials. Meanwhile the South Koreans have announced trials in 2018 and commercial service in 2020, perhaps aiming to showcase it during the 2018 Winter Olympics.
Given the uncertainty of what 5G requirements are, I think it could easily take much longer. We’ll need some clear agreements of what the goals are (probably from the ITU) before the industry can make real progress.
Perhaps the UK should rebrand its smart meter project as 5G, which will be delivered in a similar timescale.
While we discussed the finer points of multi-gigabit, low latency wireless service that 5G could offer, a reality check was the poor (i.e. non-existant 3G) cellular service at the conference venue. This isn’t unusual at conferences and no specific to any particular network operator. We already have plenty of in-building small cell technology to fix these issues today without needing 5G, but seem to lack the commercial and operational focus to make it happen.
There has been a gap of about 10 years between each new generation of radio technology, during which time the previous one matures and develops considerably. Even 2G GSM continues to evolve and remains present in almost every phone. We can expect to see substantial development for both 3G and LTE over the next 10 years, so I wouldn’t wait for 5G to come along and solve all our problems quite yet.
Moray Rumney’s 5G presentation can be found on the Cambridge Wireless event website here
In my last post Bringing LTE Indoors, I discussed the compelling need to address LTE coverage indoors to enable service migration off 3G, particularly for Voice. We know there is a variety of options for MNOs to address indoor coverage, either from outside in with more outdoor sites, or from inside with wider use of Distributed Antenna Systems (DAS), repeaters or small cells. The “outdoor in” approach would mean even more BTS sites, but site acquisition challenges and build costs generally mean this is no longer an option in urban areas. Addressing coverage from indoors makes sense, but what is the optimal solution?
I’ve heard people talking about a “toolbox” approach to indoor coverage, but which tool is right for which job? There is no point using a six inch spanner on a 1/4 inch nut, and it’s the same with providing coverage and capacity you need an optimal cost solution for the size of the indoor hole to fill.
Cisco has worked with many operators on modelling Total Cost of Ownership (TCO) for various indoor coverage solutions. The results of one recent study are shown below, comparing Distributed Antenna Systems to small cells; either installed by the MNO or by the end-user themselves (DIY).
“5-Year TCO study for various indoor coverage solutions”
Obviously this isn’t an “Apples for Apples” comparison since the capacities are so different. But even if we normalise by the number of design users, small cells show clear TCO per user benefit.
“Normalised TCO per user for various indoor coverage solutions”
The other thing I observed in this study was how much the DAS system TCO improved when a larger number of users are required to be served in a location. I therefore extended the study to look at how the DAS vs Smallcell TCO comparison varied for different sized enterprises.
“Comparison of DAS versus Smallcell TCO for various Enterprise sizes”
For small enterprises of <50 people, which represents the majority of businesses, small cells are clearly more cost effective. Due to their more modular capacity, re-use of WLAN infrastructure and easier installation small cells could be more than five times cheaper to own. As the size of the enterprise to cover gets larger, DAS TCO is more comparable, but even for large enterprise (>250 people) small cells could still work-out with 50 per cent lower TCO. Such comparisons would vary on a case-by-case basis, for example often larger enterprise locations are already covered with DAS for 3G which can be reused.
The “toolbox” approach to solving indoor coverage challenges makes sense, but for SME locations small cells seem to be the right tool for the job.
CIOs, property owners, hotel managers and other Enterprise users now seek cost effective solutions that would deliver reliable in-building cellular service – many would even be willing to pay for or contribute to the system installation. Cisco makes the bold claim that the incremental cost of adding cellular service to a new Enterprise Wi-Fi deployment can be as low as 20%. This reinforces how cost effective small cells can be, but are network operators grasping the opportunity quickly enough? Should Enterprises take matters into their own hands, self-installing cellular equipment and simply asking the operators to adopt and commission it? What tools and processes are needed and what practical implications arise?
In a brand new ThinkSmallCell White Paper, we ask what it would take to achieve “The Enterprise – Unlocked”.
Poor in-building cellular services becomes more significant as we connect fully wirelessly at work. A common combination today mixes Wi-Fi for laptop/smartphone data with 3G for direct voice calls and accessing data on the move. Rapid adoption of tablets exacerbates the demands on corporate IT departments, which are expected to ensure adequate wireless connectivity throughout business premises (and not just in meeting rooms or public spaces).
Service quality inside buildings is more difficult to maintain than before for several reasons, primarily due to the:
Take-up of Enterprise Small Cells has been slower than many of the early analyst forecasts, for reasons which are less to do with technical capabilities or equipment price and perhaps more to do with lack of marketing drive from operators, lack of scalable processes (from sales through to installation and on-going support) and lack of a clearly understood and adopted strategic business cases.
While the cellular industry moves slowly to adopt Enterprise Small cells, we’ve seen Wi-Fi deployments grow quickly to provide quality and low cost in-building data connectivity. ABI Research forecasts that the installed base of carrier-deployed Wi-Fi hotspots will grow from 4.2 million at end 2013 to 10.5 million by end 2018. That’s a small proportion of the 139 million Wi-Fi access points shipped during 2013, and still significantly fewer than the installed base of femtocells or macrocells.
The quality and capability of Wi-Fi has continued to improve and now forms a significant part of our total data communications. More than half the data sent to/from smartphones goes via Wi-Fi rather than cellular. 64% of hotels offer free Wi-Fi and 38% of hotel guests see lack of Wi-Fi as a deal-breaker. The unregulated and low cost nature of Wi-Fi has enabled rapid mass deployment that in most cases bypasses the cellular operator.
An alternative could be for building owners and IT departments to install their own Small Cell solutions. These could be engineered and deployed by in-house staff or 3rd party systems integrators, ready to be commissioned and integrated with external mobile networks. This is the norm for other utility building services, such as water, electricity, gas and even fixed line telecommunications services. Such an approach could rapidly accelerate take-up of cellular in-building solutions and complement the extensive use of Wi-Fi.
In a new ThinkSmallCell white paper, we consider whether property owners and CIOs, frustrated with progress and the available options open to them today, should take a more proactive role in Enterprise Small Cell deployment. Could we see buildings being equipped with their own cellular network equipment, ready to be commissioned and adopted by mobile operators? What are the operational and commercial barriers to making this happen?
Get your free copy today from our White Paper download section
White paper “The Enterprise – Unlocked” is written and published by ThinkSmallCell, sponsored by Cisco and iBwave.
The Cisco® Licensed Small Cell Solution is designed to address the challenge of mobile service coverage and to expand network capacity. Small cells extend voice and data services to mobile subscribers while offloading traffic from the macro network. Additionally, Cisco Small Cell capabilities are uniquely used to deploy consumer services that are based on indoor location and presence and new enterprise services such as integration with enterprise voice systems and access to local enterprise networks.
Figure 1. Small Cell Market Trends
• Cisco Visual Networking Index shows that operators can expect mobile data traffic to increase 13-fold over the 5 years between 2012 and 2017. Analysts also point to the exponential growth in signaling traffic helping to promote the data growth.
• Coupled with this growth in traffic is the lack of available new spectrum and the difficulty for operators to quickly and cost-effectively add new macro cell sites. In this environment, small cell solutions become very attractive.
• Distinctions between consumer and business services on mobile devices have become blurred. Small cells can help deliver those services transparently across third- and fourth-generation (3G and 4G) cellular networks and Wi-Fi.
• Wireless usage is shifting indoors. Network analytics show that the majority of mobile data usage – close to 80 percent – is indoor and nomadic, rather than truly mobile. Macro networks were built for voice on the go. Small cell networks are designed to address modern mobile data traffic patterns.
• Small cells offer new monetization opportunities by taking advantage of the intelligence inherent in the network, including policy, hyperlocation, context, application, and device information. Businesses can use this information to engage with their customers in new ways, including through augmented experiences, location-based content, and personalized loyalty programs.
Improve and Enhance End-User Services
• Automatic profile switch when entering home (for example, moving from business to personal services)
• Short Message Service (SMS) alert when a family member comes home
• Application triggering with a state change (for example, linking with Facebook)
Connected Home Services
• Backup of mobile hosted content (music or pictures) to the home PC
• Playing videos or slide shows from the phone to another element
• Transforming the phone into a remote control for other elements
• Integration of mobile handsets with the enterprise PBX dial plan and services
• Local access to the enterprise LAN.
Cisco Licensed Small Cell Solution Overview
• Frictionless deployment: Cisco offers operational ease by applying network intelligence that is based on years of design and implementation expertise. From radio performance to policy and management to backhaul, we design simplicity into our solution to keep operators’ costs down and mobile users satisfied.
• Innovation for business results: Cisco is guiding the market toward a unified and scalable standards-based licensed and unlicensed architecture for wireless service delivery, meeting the needs that result from the dramatic increases in consumer capacity requirements. On top of this we add analytic tools that operators use not only to monitor the network, but to monetize the network, allowing operators to unlock new business models.
• Real-world heterogeneous networking: We deliver standards-based self-organizing network (SON) technology, not just for fully integrated heterogeneous 3G, 4G, and Wi-Fi networks, but also for multivendor network deployments. Our solution provides an elastic, flexible architecture of infrastructure and software with intelligence.
Cisco Licensed Small Cell Architecture
• Enterprise and home small cells
• Small cell gateway
• Management and provisioning
• Small cell backhaul
Figure 2. Cisco Small Cell Solution
Enterprise and Home Small Cells
Cisco 3G Femtocell
Cisco 3G Small Cell
Figure 3. Cisco 3G Small Cell
Cisco 3G Small Cell Module for Cisco Aironet
Figure 4. Cisco 3G Small Cell Module for Cisco Aironet
• Increased mobile network capacity and coverage indoors, where it is most needed. Usage reports show that up to 80 percent of mobile traffic today occurs indoors and while people are stationary.
• Reduced network costs and operations. By having a self-contained small cell radio, mobile operators have the ability to quickly and easily deploy either with a desktop-mounted solution or a wall-mounted solution. And by integrating the 3G Small Cell Module into the Aironet 3600 Series, network, power, and operating costs are dramatically reduced.
• The capacity to install, power up, and go with zero-touch configuration. There are no extra steps required to enable Cisco small cells to run in a Dynamic Host Configuration Protocol (DHCP) environment. This approach can quickly provide 3G coverage to end users.
• Self-optimization based on back-end network intelligence for easily managing millions of devices so they do not cause interference with neighboring femtocells, picocells, and macro cell towers.
• Secure, carrier-grade 3G base station technology. Cisco small cells provide the technology equivalent of an in-building mini cell tower. The device is secure and fully managed by the mobile operator to provide for 3G signals inside an office or enterprise.
• Standards-based technology. A Cisco small cell operates as a HNB in the standard 3GPP architecture for small cells and is connected to the network with the specified Iuh interface. This architecture provides for rapid deployment and multivendor interoperability.
Cisco ASR 5000 Series Small Cell Gateway
Figure 5. Cisco ASR 5000 Small Cell Gateway
Small Cell Backhaul: Cisco ASR 901S
Figure 6. Cisco ASR 901S Series Aggregation Services Router
• Flexible architecture that supports true multivendor “any-G” heterogeneous radio technology and backhaul topologies
• Dramatically reduced operating expenses (OpEx) and TCO through zero-touch provisioning capabilities and extensive management tools
• Unsurpassed user experience through Cisco’s best-in-class routing and comprehensive end-to-end operations, administration, and maintenance (OAM) capabilities
Cisco Quantum Radio Access Network Optimization
• Automatic neighbor relations: Monitors connections between cell sites and automatically adjusts neighbor lists for subscriber handoff to help ensure overloaded cells are bypassed and unused cells are removed from neighbor lists to reduce OpEx
• Load balancing: Shifts traffic between cells, based on availability, congestion, and blocking of radio resources, so that traffic within a cluster of cell sites is evenly balanced across all access technologies
Management and Provisioning
Figure 7. Cisco Small Cell NMS Layer
Small Cell Remote Management System
Cisco Broadband Access Center
Cisco Provisioning and Management Gateway
Cisco Management Heartbeat Server
• Real-time status reporting for all small cells
• History of small cell status
• Monitoring of small cell connectivity through ongoing heartbeats
• Status profiling by groups of indicator values
• Notifications about key indicator changes
• Connection requests for TR-069 session over Network Address Translation (NAT)
Small Cell Service Assurance: Cisco Prime
Cisco Prime Network
Cisco Prime Performance Manager
Cisco Prime Central
• Plan: Create an agile infrastructure and cost-effective strategy with service capabilities ranging from architectural consulting to detailed design.
• Build: Speed time to value and reduce deployment risks through solution validation, solution integration and deployment, and migration support. Validate that the solution meets requirements through specialized labs for small cell interoperability testing and system verification testing.
• Manage: Improve performance, availability, and resiliency; reduce costs through service offerings that provide better network insight, help improve network inventory management and health, and identify and mitigate potential problems before they can affect the network.
• Deliver high-bandwidth applications to indoor locations from an indoor location
• Meet today’s increasing bandwidth demand at dramatically lower costs
• Break the small cell backhaul bottleneck with ruggedized cell-site routers
• Delivers comprehensive security, exceptional scalability, and fast time to market
• Is autoprovisioned and uses existing handsets for improved voice and data coverage
• Is standards-based for real-world heterogeneous networking
LTE as a technology and air interface has been hogging the bulk of limelight in the world of wireless communications. But another strategically crucial technology that many major mobile operators globally are going after is the small cell. In simple terms, small cell is a miniature version of the traditional macrocell. It compresses the attributes of a cell tower like radios and antennas into a low power, portable and easy to deploy radio device. Small cells typically have a range varying from 10 meters to a few hundred meters and are used by operators to either offload traffic from the macro network in a high density short range environment or to strengthen the range and efficiency of a mobile network. Before going into further details about small cells, have a look at the following diagram that illustrates how they fit into an operator’s network and strategy.
As seen in the image above, small cells provide enhanced coverage and capacity both indoors and outdoors. Umbrella coverage is provided by the macrocell. Microcells and picocells are designed to support hundreds of users and can be used in smaller networks that are not necessarily inside the range of a macrocell. Residential areas that are located outside the range of a cell network can deploy femtocells for better signal and bandwidth indoors. WiFi can be utilized for traffic offload or can serve as a standalone high speed short range network. Following are some of the advantages that small cells bring to the table –
Many operators and vendors around the globe showcased their small cell strategy and progress at the Mobile World Congress (MWC) in Barcelona earlier this year. Vodafone emphasized that this technology is vital to their network portfolio. The telco plans to deploy about 70,000 small cells within the next 2 years. Korea Telecom announced that they have 18,000 such cells already active in urban areas of the country. Samsung Mobile was tapped by Verizon as a vendor for indoor LTE small cell solutions. Verizon already had similar partnerships with both Alcatel-Lucent and Ericsson for indoor enterprise and outdoor environments. TIM Brazil, the country’s second largest operator, shared details about a deal with Alcatel-Lucent at MWC that will integrate femtocells into the carrier’s 3G network. SingTel from Singapore has been investing in these tiny networks too and has contracted Ericsson for the deployment. Many other small cell related developments have been picking up in the last year or so. AT&T’s 3G small cells are available in 18 states across the US. The operator has committed to deploying 40,000 multimode little base stations by the end of 2015. Sprint has been testing indoor and outdoor small cells for many months and intends a commercial launch later this year. The telco has also been running trials with Qualcomm’s network equipment. World’s biggest wireless service provider by subscribers, China Mobile, recently showed off a self-organizing outdoor small cell backhaul system as part of its TD-LTE network. Japan’s NTT Docomo has been using multiband small cell base stations for more than a year in some of its major markets. Note that as of now, most small cell networks operate on service provider’s existing spectrum holdings. But in the near future, dedicated airwaves could be allocated for these networks.
Multiple recent studies and analyses have predicted a ramp up in the small cell market. Infonetics Research has reported that small cell revenue was a modest $771 million last year but will grow by 65% to $1.3 billion this year. According to their report, 642,000 small cell units were shipped last year and about half of them were 3G, although LTE is projected to take the lead this year. ABI Research forecasted $1.8 billion market for outdoor small cells in 2014. The Asia-Pacific region will represent half of the small cell market by 2019. Allied Market Research put the global femtocell market size at $305 million in 2013 and predicted that this could grow more than ten-fold to $3.7 billion by 2020.
Although the predictions are upbeat, challenges remain for the small cell ecosystem. The cost and availability of backhaul for such stations is an issue. Because of municipal regulations, outdoor site acquisition can be a problematic process. The coordination and synchronization of these cells with local WiFi and the macro network is not as easy as it sounds. In urban scenarios, achieving line-of-sight may be technically difficult for low height in-building base stations. Despite these challenges, the overall small cell industry outlook is favorable. All major telcos and equipment providers have been evolving a small cell strategy. With consumers becoming increasingly intolerable towards bad wireless service, these tiny towers and stations are set to establish a niche but substantial market for themselves.