DAS, signal boosters and a small cell/DAS hybrid approach to in-building wireless for the enterprise
The need for robust in-building wireless systems for enterprise users is well-established. The vast majority of mobile traffic originates inside buildings, and, particularly in the context of an office, retail center, hospital or other enterprise environment, the common approach of providing coverage from the outside-in just isn’t enough. While high-quality Wi-Fi systems support a broad range of wireless connectivity requirements, it’s still difficult to depend on a voice-over-Wi-Fi connection when a big sale or other mission critical communication hangs in the balance.
Mobile service providers spend billions installing, upgrading and maintaining in-building wireless systems in venues including airports, convention centers, stadiums, high-volume tourist areas, college campuses, commercial real estate and other locations. Marquee venues like those listed accommodate a large number of ratepayers or priority business customers. For carriers, this is an attractive investment. However, there’s only so much money available for capital investments. It has become clear that it’s not financially viable for carriers to meet all of the demand for in-building wireless coverage and capacity, which is prompting changes in the technological and business case aspects of the market. Enterprises are increasingly looking to solve for their own connectivity needs, which means network infrastructure vendors have to adjust product lines and sales approaches to better meet the niche needs of non-carrier customers.
Here we look at three options for lowering the cost of in-building wireless connectivity to make investment more attainable for enterprise buyers.
A new approach to DAS
Distributed antenna system vendors are working to the make products more enterprise-friendly by reducing the cost and complexity while still providing the multi-operator, multi-band support that’s needed by many businesses who have embraced the bring-your-own-device trend and adopted bandwidth-intensive applications such as a real-time workflow sharing, video conferencing and other tools.
Tim Moynihan, vice president of marketing at SOLiD Technologies, said that user experience is key. “We tend to talk about technology,” he said. “Let’s talk about user experience, let’s talk about what the enterprise IT departments want. It’s all about the application; it’s all about the user experience and how it’s supported by enterprise IT. They want happy customers, they want a happy CEO, they don’t want to take [complaint] phone calls. They want to manage it, work with it and work with as few vendors as possible.”
To enable a user-friendly, easy-to-manage DAS solution, SOLiD launched its GENESIS platform, which includes four primary components: the DAS infrastructure, a virtualized radio access network signal source, cloud-based management, and a marketplace application, which enables what SOLiD refers to as a “supply meets demand” relationship between system owners and wireless service providers. Ken Sandfeld, president of SOLiD Americas, said that “the reason [the middleprise] hasn’t been solved for so long is, it has been a very unbalanced relationship between the building owner and the carrier.”
Signal boosters or passive DAS
The term “signal booster” is often associated with a consumer-facing product meant to amplify indoor cellular coverage often in a residential setting. However, Frankie Smith, vice president of sales for SureCall, explained that the company’s enterprise-focused product lines often serve as a passive DAS capable of supporting the connectivity needs of enterprise spaces. Smith said that, for many enterprise-led investments, passive DAS is an attractive option given the approachable price point.
“For the enterprises,” Smith said, “we know there’s a need for better in-building coverage. There are several different types of solutions that can cover it, but with our approach we don’t trunk into the network. We take the signal that’s coming from the macro cell from an antenna we place on the roof. It captures that signal, then brings it down into an amplifier or series of amplifiers, and from there it goes out to a series to indoor antennas to broadcast that signal. It’s carrier agnostic. It’s simply rebroadcasting the cellular signals inside–what you get outside, you get inside.”
Surecall’s most powerful enterprise solution is the Force5, which supports CDMA, WCDMA, GSM, EDGE, HSPA+, EVDO, LTE and other cellular standards in an 18-pound unit. The Force5 connects to an outdoor antenna and indoor antennas over coaxial cable; the hardware is software-upgradable and has the ability to save power by making the uplink dormant when not in use.
Small cell as a signal source for DAS
Acquiring a baseband unit from a carrier and installing it to support an active DAS system is a huge cost and time investment — this isn’t something an enterprise can do unilaterally. This has given rise to a hybrid approach to distributing signal throughout a building. Instead of the baseband unit, a small cell is used as the signal source to feet the distributed antennas of the DAS. With Verizon Wireless recently asking its DAS suppliers to integrate SpiderCloud Wireless small cell units into their systems, there’s growing interest in this hybrid approach to serving the enterprise space with coverage and capacity.
Using a small cell to provide a signal source for a DAS makes the radio part of the DAS vendor’s equipment, and could help meet pent-up demand for in-building wireless by lowering the price point to facilitate the shift in capital expenditure from the carrier to the end user. “This allows the enterprise to get a guaranteed signal source and distribute it with the DAS system if they choose to do so,” said Verizon’s Dennis McColl, the principal engineer who heads up the carrier’s in-building business. “The DAS systems themselves are meant to mimic an air interface so there’s really no reason why a DAS cannot be applied to the SpiderCloud radio node. It’s not easy,” he continued. “DAS systems are certainly not easy. They’re the most complex, underestimated piece of equipment or architecture in the wireless landscape.”
