Alcatel-Lucent's next-generation mobile networks will use slimmed-down base stations that can be placed almost anywhere in order to improve coverage and mobile broadband performance, and cut costs for operators, the company said.
A base station typically consists of an antenna, a signal amplifier and a baseband unit, which handles the data and call processing. In a traditional base station, all these parts are located together.
However, to be able to cope with ever increasing amounts of data traffic from smartphones, tablets and laptops, mobile networks will have to be redesigned. Alcatel-Lucent's answer is a new range of network products called lightRadio, which shrinks antennas and amplifiers and centralises the baseband units.
The key element is the lightRadio Cube, a 60mm block containing an antenna and a signal amplifier. Its small size will allow operators to put it almost anywhere, including on lamp posts and the side of buildings, as well as in more traditional places such as on rooftops, said Wim Sweldens, president of Alcatel-Lucent's Wireless Division. That will allow operators to place the cubes where there is a high concentration of users to improve coverage and data performance.
A cube won't be able to handle as many users as a regular-sized base station, but Alcatel-Lucent is getting around that by making it possible to put a number of them at the same location.
The lightRadio Cube has a software-based radio that can be used in any spectrum band from 400MHz to 4GHz in both 2G, 3G and LTE (Long Term Evolution) networks, Sweldens said.
While the antenna and amplifier remain together, Alcatel-Lucent has centralized the rest of the base station's functions. That means carrying the radio signals unprocessed to a central location, which requires more bandwidth than carrying the data traffic after baseband processing.
Compression can be used to lessen the load, according to Alcatel-Lucent, but operators will still have to use fiber between its cubes and the centralised part of the network, for now. The company is also working on more advanced compression technology that will eventually allow microwave radio or copper cables to be used as alternatives to fiber to haul the data back to the central processing site.
This part of operators' networks, called backhaul, has been under the most pressure due to growing amounts of data traffic from smartphones and wireless modems. To cope with data volumes, operators have already begun to install fiber connections, especially when upgrading to LTE and faster versions of HSPA (High-Speed Packet Access).
The new architecture should also help operators lower management and maintenance costs; and cut the electricity bill and carbon dioxide emissions, according to Alcatel-Lucent. For example, centralising part of the base station means maintenance staff won't have to visit every site when doing an upgrade. It also means operators won't have to negotiate and pay for space to put the equipment at every site.
The lightRadio concept is not going to become a reality overnight; it is Alcatel-Lucent's long-term strategy for mobile networks. The related products will be rolled out in commercial networks mobile networks over the next couple of years, and the full architecture will be ready by 2013, Sweldens said.
For example, trials of the cube technology will start later this year and become widely available in 2012.
Alcatel-Lucent is planning field trials of the lightRadio architecture with a number of large mobile operators, including Orange.
Alcatel-Lucent's lightRadio approach will be demonstrated at Mobile World Congress, which takes place in Barcelona between February 14 and February 17.