ADVA is making an aggressive push into the mobile backhaul market with an AnyCell fiber system designed to support almost any mobile bandwidth need.

The ADVA Optical Networking AnyCell Connectivity system combines tried-and-true Carrier Ethernet backhaul capabilities with the time and phase functionality needed for managed optical fronthaul, using wavelength division multiplexing (WDM). The goal is to support the diverse landscape of the modern Radio Access Network (RAN), which will include macrocells, small cells, and the move to a cloud-based RAN using remote radio heads.

"This is about positioning for LTE-Advanced, the next major step in LTE," says Heavy Reading analyst Gabriel Brown. "Mobile operators are looking at dark fiber or wavelength services as an evolution to conventional cell site backhaul to provide the scalability and latency required for LTE Advanced."

In addition, Brown says, there is "strong interest in using WDM in fronthaul links to connect centralized baseband processing pools to remote radio heads deployed on the tower or lamppost -– for example, as used in Cloud RAN deployments."

Fronthaul is the transport network, usually fiber-based, that connects a baseband processing unit with distributed Remote Radio Heads (RRH) in a Cloud RAN or other distributed cell network.

Brown adds, "The extreme throughput and latency requirements make WDM pretty much the only scalable option for fronthaul. Dark fiber is also attractive, but can be harder to scale. Microwave services, and perhaps switched Ethernet, will have a role, but it will probably be more tactical."

ADVA intends to give the companies building mobile backhaul networks the maximum flexibility to support the RAN as it evolves, realizing that evolution is not totally predictable, says Stephan Rettenberger, vice president of marketing for ADVA.

"These guys have a huge business opportunity in front of them because it is not realistic that mobile network operators will fiber up every cell tower themselves, and they are looking for a partner to bring fiber," Rettenberger says. "What we are providing is the ultimate flexibility, as long as [the network operator] has fiber to the tower. If customers decide they want fronthaul, or if they need traditional carrier Ethernet with synchronous timing, we can support that."

The ADVA AnyCell system is designed to support an evolution to what the company is calling supercells. These will combine the mobile fronthaul capability for a centralized RAN with more capacity, lower latency, and more transparency, along with next-gen backhaul that can support the diverse deployment of small cells by offering more nodes and deployment options and a network that reaches all the way to the small cell.

ADVA's technology is already in use for mobile backhaul and it is trialing the synchronized delivery with a number of carriers today. But, the fronthaul capabilities are new, Rettenberger says. The company will be demonstrating AnyCell at Mobile World Congress next week.

— Carol Wilson, Editor-at-Large, Light Reading