Designing Backhaul for the Nascent Small-Cell Market Not for the Timid

While operators in the small-cell ecosystem try to figure out how they are going to make money and, more importantly, avoid losing it on small cells, equipment vendors are refining the products that will make the market possible. But they’re doing so with a little trepidation.

“The outdoor metrocell market does not exist today. [Making an outdoor small-cell product] is a little scary,” Alan Solheim, VP corporate development, DragonWave, told DAS Bulletin. “It all makes sense. People need a solution to [the data surge problem], but it would be easier to make a product if someone is already buying a million of them. You know what they want. On the other hand, it is a great opportunity. It allows us to innovate and define the market.”

Because an LTE base station has more capacity, tighter latency and synchronization requirements than does a 3G base station, backhaul for it requires corresponding performance characteristics in the backhaul radios. Dragonwave designed its radios to provide the performance that LTE needs.

DragonWave’s Avenue Link Lite is a from-the-ground-up replacement of the Horizon S-Series. It follows three major trends. Compared with its predecessor, it is smaller, has higher performance and offers lower power consumption. Two-by-two MIMO outputs double the throughput.

“One of the big things about small-cell applications is you can’t use conventional antennas. The antennas have to fit inside the packaging constraints,” Solheim said. “The packaging cannot look like a microwave transmitter.”

Because of the radio’s high performance, it will eventually be built into Dragonwave’s other products, such as the Harmony line.

“When we started doing small-cell networks, we quickly came to the conclusion that we needed a variety of technologies to tackle the backhaul problem — higher frequency, higher capacity, lower latency, point-to-point links — but on the street level you need non-line-of-site capability to make the signal go around corners and around trees,” Solheim said. “Operators are demanding not just one technology for small-cell backhaul, but multiple technologies to fit different situations.”

After the small-cell hype of the last year, Solheim said it is necessary for vendors to begin rolling out the hardware.

“First, a technology is hyped and gets a lot of attention, then everyone finds out about the challenges and it falls off a cliff,” he said. “It rises again when the solutions to those issues are found. We are somewhere in the middle of that scenario.”

Looking into 2013, Solheim said the year will be characterized more by pilots, and trials are more the norm than mass deployments.

“We still feel the carriers will be preoccupied with building out their LTE macrocellular footprint,” he said. “When coverage is complete, then they will use small cells to fill in underneath to grow network capacity to fulfill their fast-download capability claims.”

Designing new networks takes a fair amount of time to figure out what is needed and then for the vendors to develop solutions, according to Solheim.

“We are at the point in time where it is appropriate to be having these conversations, but we have continued evolution in front of us as we find out what the mass deployment of small cells is going to look like,” he said. “It has the potential to fundamentally change the way we build wireless networks.”