By Martha DeGrasse, originally published in RCR Wireless News on 11/2/15.

What’s holding back multi-operator small cells?

Small cells that can support more than one mobile operator have the potential to change the wireless landscape, particularly indoors. With more than one carrier tenant paying rent, small cells become attractive investments for neutral host providers and tower companies. Indoor small cells have the potential to alleviate “dead spots” in thousands of buildings, and neutral host providers are ready to deploy if they can see a return on investment. So what’s the holdup?

At least two companies, SpiderCloud Wireless and Airvana (now owned by CommScope), have developed small cells that can support more than one operator. But so far, there have been very few actual deployments in the United States.

“We’re working toward it but we run into this incentive issue because small cells are being used by the operators to take subscribers from … other operators,” explained Art King, SpiderCloud Wireless’ director of enterprise services and technologies. “So the incentive of the operators is not to light the enemy spectrum, they want to make their spectrum awesome and they don’t care about anybody else.”

King was part of the “HetNet Experts” panel (pictured above), moderated by David Bronston of Phillips Lytle, at last week’s HetNet Expo. He said that many enterprises can’t afford to pay for a system themselves, so if one operator offers a small cell solution, the enterprise will often take it.

Small cell vendors are not alone in their frustration. Tower owners have made billions renting space on towers to mobile operators, and now they want to use the same model for small cells. Deploy once, and then rent the infrastructure to two, three or even four carriers – that’s the model the tower owners would like to replicate indoors. The solutions that have hit the market so far, however, have not gained traction with the tower companies.

“Looking for a neutral host solution, we believe this is the biggest challenge for small cells today,” said Fakri Sadeh, director of engineering at American Tower. “That’s why [distributed antenna systems] continues to be the dominant solution for in-building needs. It was interesting that it was almost a year ago that the statement was made that DAS is dead. We’re still talking about DAS.”

But DAS is too expensive for most buildings, and DAS vendors know it. CommScope, the world’s largest vendor of DAS equipment, acquired a less expensive in-building alternative with its purchase of Airvana.

“We believe enterprise is really the future of DAS and I think there is a convergence … between DAS and small cells,” said Patrick Lau, CommScope’s director of business development. “I think if you look at …. the newer generation of DAS … the features [are]becoming digital. There are several vendors in today’s market providing that feature, which is digital … while maintaining the DAS characteristics, which is multicarrier and providing technologies as a neutral host.”

One of the more recent in-building trends is to use a small cell as a signaling source for a DAS. According to analyst Joe Madden of Mobile Experts, some venues are replacing large racks of DAS head-end equipment with clusters of small cells. Each small cell may support a different operator. If a multi-operator small cell were used, the footprint could be even smaller.