We've all been there. Pick almost any multitenant building, hotel, or office tower and try to get a strong cell signal while inside it. People usually end up going to a window, where they pick up whatever remnants of their carrier's signal make it through the glass. And good luck if the windows have been treated with low-E film since that stuff turns buildings into virtual Faraday cages. That used to be just an inconvenience. But today practically everyone not only has a smartphone but everyone relies on it for the majority of their voice communications. And those cell-hungry business mobile applications that used to be just nice-to-haves are turning into critically important, frontline business apps. That means getting solid cell reception when tenants are inside is something landlords and real estate developers are being forced to take seriously.
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"It's becoming more of a trend to ask why there isn't service and there are several big-time real estate players that are just now waking up and realizing that this in-building wireless thing is real," said Scott Gregory, Director of Marketing at Distributed Antenna Systems (DAS) equipment vendor SOLiD, Inc. "They're saying, 'If we don't get onboard, our properties will lose value,' and that's a major consideration."
The trend of doing business by using all kinds of apps that require major bandwidth over smartphones has transformed everyone's expectations as we've moved to an "always-on" way of life. "For many business people, a smartphone is their only means of communication so they'll remember if they can't make calls in your building," added Gregory. "If you're the owner of the property or a long-term tenant, you know this is bad for business."
An IT Opportunity
On the other hand, it's great for business if IT can provide strong coverage that's coupled with huge capacity. Property owners can charge a premium per square foot for leases in the buildings and you'll have happy tenants. Hotels? Happy guests. But this is no easy task since carriers' networks are designed for outdoor use and their signals weaken as they pass through buildings. It's even more tedious when 80 percent of all cell calls originate indoors. Currently, technologies that are poised to facilitate in-building wireless (IBW) networks include DAS, Small Cells, IP (Wi-Fi), and hybrids of those, depending on building structural considerations.
Solutions for buildings sized at 500,000 square feet or less—also known as the "middleprise" in these circles—need to become flexible enough to support these multiple services. They also need to become flexible enough to support multiple operators and, along with new infrastructure, multiple bands and legacy equipment. The ideal infrastructure should deliver a converged network where a single backbone serves multiple services, including commercial cellular, public-safety, and IP (Wi-Fi). Thus, the we are seeing a move toward Self-Organizing Networks (SON)—and there are some interesting new solutions rising to address this transformation. For most IT managers, however, it's difficult to separate the truth from the hype in the industry fight between small cells and DAS.
"The great debate begins about which tool is more effective for enabling coverage in the middleprise and where the demarcation line lies," said Mike Collado, former Vice President of Marketing for SOLiD and a brand evangelist. "It really comes down to cost per square foot. At a certain point, conventional DAS becomes too expensive, which has opened up the door for small cells."
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DAS is ideal for large deployments while small cells are better for smaller installations. But, according to experts such as Collado, what really needs to happen is that DAS needs to look more like a small cell and a small cell needs to look more DAS. DAS needs to reduce its cost and make deployment simpler. Small cells are limited to one or two bands or carriers when they should support multiple bands such as DAS.
"There are many challenges to bringing cell coverage to US properties," Collado explained. "Unlike in Europe or Canada where carriers share spectrum with each other, the big four in the US do not—which is why you'll see separate layers in a large DAS deployment."
Property owners who decide to go with small cell right now will have to figure out which one or two of the big four carriers service the majority of their customers. That information will dictate which small cells they deploy.
The Scoop on DAS
DAS is a technology that brings the carrier's signals inside a building and then re-transmits them inside that building by using radios and antenna. Because DAS brings existing signals into the building, they aren't handicapped by degradation (or signal propagation as the industry call it) that can be caused by building materials such as concrete and steel. It can also support multiple carriers' networks on the same system.
A carrier network works by creating wireless signals via a network of base station towers (BST). Two-way communication happens when these signals are transmitted to cell phones within the tower's geographical area and the phones send the signal back. Just as satellites work for GPS, these BSTs create a coverage footprint. Coverage weakens as you get to the outer edges and then dissipates once you're entirely outside the footprint. You can check carrier websites to get maps of their coverage areas if you're unfamiliar with that carrier's network. If your building is on the edge of a carrier's coverage map, then it's likely that your tenants are having trouble with that carrier's connections.
Capacity (meaning how many phones are attempting to communicate with a single BST simultaneously) can also create problems. You can tell the difference between coverage and capacity by using a basic method: If you're well within your carrier's coverage area, then your phone will be showing strong reception. However, if you're still experiencing dropped calls or slow data transfer, then you're caught up in a capacity issue.
There are two different types of DAS: Passive DAS and Active DAS. Passive DAS works by capturing the signal from outside the building with an antenna, strengthening it with an amplifier, and then transmitting it to antennas inside the building. It usually uses copper coax and it's a good solution for smaller properties. Active DAS uses a carrier-provided BST that produces the cellular signal directly. The signal source connects to the DAS head-end that sends the signal to radio units over fiber optic cable. The remote unit sends the signal to antennas over coax. It's great for buildings of any size.
Collado explained where Active DAS began. "Traditionally, Active DAS found its home in large venues like mass transit hubs, shopping malls, casinos, and stadiums," he said. "And by large, I mean over 500,000 square feet. It began here for the very simple reason that property owners wanted people to stay on property and spend money rather than leaving."
The Small Cell Play
Small cell technology is another option for property owners. A small cell is an operator- or carrier-controlled radio access node that has a coverage range from 10 to several hundred meters, according to the Small Cell Forum. There are different types of cells that include the smallest femtocell and increase in size to microcells, the largest. They operate in licensed spectrum and unlicensed carrier-grade Wi-Fi. A benefit to this solution is that it can be cheaper and more flexible than having a carrier install a BST for a DAS. Another cool aspect is that they appear less visually intrusive and, because they're small, they lend themselves to more flexible mounting location options. To boot, there are in-building as well as outdoor models for properties that want to extend access to outside campus areas such as courtyards, gardens, or parks.
The downside (to which we've already alluded) is that, currently, most cells support only one specific carrier network so it won't take care of all your tenant's needs. Art King, Director of Enterprise Services and Technologies at SpiderCloud Wireless, came to SpiderCloud from previously serving as Mobility/Collaboration lead in Global Architecture at Nike. King defends the carriers' cautious approach when guarding their spectrum.
"I wanted to buy this technology but I couldn't because it lights up operator spectrum," King said. "I was completely ignorant about how difficult it is to be certified to connect to an operator's network. Once I got inside, I understood how hard it was to create a template for only 130 million people—and it has to be bulletproof," he said. "The level of engineering that an operator is held to is far higher than an enterprise. Now I consider what we did in the enterprise fairly reckless."
The small cell vendor and carrier community is well aware of the barriers King mentions. Work is in progress to transform the current state of the technology into a more open environment, one that's multi-operator, multi-technology, multi-spectrum, and multi-domain. A more open environment that's basically a multi-"x" environment (currently called a HetNet, which refers to a heterogeneous network). What a HetNet means to property owners is that they'll benefit from new services, higher quality of existing services across multiple carriers, and likely all this for less money. Emerging solutions include small cell/Wi-Fi integration, the SON evolution, and small cell integration with 5G standards.
Testing and Quality Control
While HetNets are on their way, currently when an IBW network and its services are turned on, it all must work properly. This means a level of testing and quality control that many IT generalists simply don't expect. Coverage, capacity, infrastructure interoperability, and scalability are just some issues that need to be covered. Getting it right means bringing testing into the process early during the site survey and network design phases, and then bringing in testing again once the network devices have been placed on location.
"We use Landslide to make it really easy to install these things by testing in the lab," said Ross Cassan, Director of Product Marketing, Mobility Infrastructure at Spirent Communications, who speaks to small cell testing. "We provide the test network that sits behind the cell so they can start testing right away, reduce the complexity of the install, and take weeks off their schedule."
The company's Epitiro product line is used by service providers to monitor small cell/DAS quality of experience. That's designed to work after initial deployment and during on-going operation for both Wi-Fi and LTE networks. Pierre Lynch, Lead Technologist and Product Manager at Ixia (a key Spirent competitor) recommends that a test partner be involved at the very beginning of the network design stage. He recommends this both for QA input as well as to ensure that existing IT management tools, particularly network monitoring but also things such as asset management, will work with the new installation.
"Start when you put in all the wiring and layout all the microfilms," said Lynch. "Whether it's DAS or small cells, and there are arguments to be made for both,...small cells [give] you as much coverage as DAS, just with higher capacity."
Lynch is a small cell proponent and explains, as a member of Small Cell Forum, that one of their emphases this year is on high-density enterprise environments. He also advises that testing begins pre-deployment in the lab. He recommends capacity testing, handover testing, and Wi-Fi interaction. He also explains that testing is needed after the deployment is complete as well. All IBW networks will require new equipment as well as new infrastructure management and monitoring tools that can work for the new infrastructure as well as existing legacy equipment.
A New Product Landscape
At CTIA Super Mobility 2016, a host of new products that support multi-x technologies were showcased that may ease the burden of providing in-building cell coverage and wireless access. For the most part, they use solid, emerging technologies, so making an infrastructure investment with one of them can often avoid expensive rip-and-replace scenarios down the line.
One of the most interesting is SpiderCloud's Enterprise Radio Access Network (E-RAN) system. It uses standard Ethernet LAN/VLAN technology to solve the growing capacity demands being made by cell tech and mobile app services. Its two components are Radio Nodes and Service Nodes, which connect over a standard Ethernet LAN. Its Services Node uses SON technology to configure a dense network of Radio Nodes to ensure key performance indicator (KPI) expectations.
"What we've built is an IP-attached infrastructure where we're delivering LTE service throughout the building but the signal radiation is at the small cell itself," King explained. "It has a lot of synergy with the enterprise infrastructure already in place."
It's scalable, too. Large buildings usually have their own Services Node installed on-premises and smaller buildings can share one that's located in a data center. SpiderCloud's products are currently available through Verizon but the company has struck an agreement with Cisco, which will be "OEMing" their products in the near future.
SureCall's Fusion 7 is a 7-band signal booster that strengthens cellular, Wi-Fi, and HDTV signals. It extends range and complements SureCall's industrial strength Force 7 signal and Wi-Fi booster. Both are products that present a cheaper option to DAS as well as being carrier-agnostic; this means they'll work well in emerging HetNets. Signal boosters are small cells that grab existing cellular signals and re-broadcast them. They're great for improving coverage in specified areas but they won't increase network capacity.
If you want to keep track of how tenants or guests feel about their network coverage, then Mosiak Solution's Signal Insights is a Software-as-a-Service (SaaS) solution that measures and analyzes the customer's experience on cellular or Wi-Fi networks. Available for Android smartphone users, the app has a cloud-based dashboard that measures indoor and outdoor signals and throughput quality. It also cranks out KPIs, signal strength, downlink speed, latency, packet loss, and other data that you need as part of your site survey.
In-building cell coverage is no longer a growing trend but an accepted necessity. Property owners and managers can start their upgrades now and take their time designing the most cost-effective solution, or they can resign themselves to scrambling when their customers start complaining about low-rent coverage and moving to the competition. For those looking to get started now, check out these 10 steps to IBW success.