Typically, before a DAS signal goes from the base band unit (BBU) to the DAS headend, it must first go through a remote radio head and an attenuation panel. This requires a lot of equipment at the headend, as well as power and space. TE Connectivity and Alcatel-Lucent have developed a solution to solve this problem, allowing mobile operators to reduce the time, components and power required for DAS, according to Tony Lefebvre, director, product management, Global Wireless & Services, TE Connectivity.
The solution consists of a common digital interface between the Alcatel-Lucent mobile Ultra-Broadband access portfolio and the TE FlexWave digital DAS.
Alcatel-Lucent and TE Connectivity cooperated on a CPRI interface that removes the need for RF processing and attenuation panels on-site, which reduces the amount of physical equipment needed by more than 50 percent and the cost of materials by 40 percent. Additional cost savings will be achieved by using less power (equipment consumption and cooling), space and fiber, resulting in operational improvements.
“CPRI eliminates inefficiencies, taking the digital signal all the way from the BBU to the DAS remote unit and converting it to RF a single time,” Lefebvre told Small Cell Link. “It also helps from a performance level, because every time you hit one of the components in the traditional DAS, you start to eat into your EVM budget. CPRI allows you to stay at a higher-level QUAM modulation and higher data rates.”
CPRI defines how the signal is transported from the base band to a remote radio unit or to the RF processing stage, which allows Alcatel-Lucent’s equipment to “talk” with TE Connectivity’s equipment.
Why is TE only doing this with Alcatel-Lucent?
“Because CPRI is really not a standard,” Lefebvre said. “It provides TE’s engineers with instructions on how Alcatel-Lucent packages its information, so they can integrate it with our digital bit stream. We are open to working with the other base station OEMs. We need information from the base station manufacturer, which we get through an interoperability agreement.”
The CPRI agreement with TE is further evidence of Alcatel-Lucent’s focus on small cell network densification solutions.
“Alcatel-Lucent is looking at how networks are going to be delivered differently in the future,” Lefebvre said. “They have some very innovative small cell products. This is very complementary to their small cell offering.”