Nortel trials collaborative MIMO

Already one of the biggest proponents for multiple smart antennas in the WiMAX kit, Nortel Networks is adding a new facet to its Multiple Input/Multiple Output (MIMO) technology. It’s developed what it calls uplink collaborative MIMO, which can send multiple streams of information from different users over the exact same frequencies.

Normal’s MIMO is focused on adding capacity to individual users on a dense urban network, using multiple antennas on a single device to send either two signals over the same frequencies to the cell site. Those dual signals can be contain either the same information, creating a resilient and redundant connection, or different information, doubling the capacity sent over any given channel. But Nortel’s collaborative technique is following the latter approach, but instead of sending those dual signals from the same device, it allows two separate devices to transmit different signals over the same frequency simultaneously, allowing the base station to support double the amount of customers on the same spectrum.

“Some carriers are more interested in the number of subscribers they can support with MIMO than they are in bandwidth to the individual subscriber,” said Bruce Gustafson, director of WiMAX marketing for Nortel. “We’ve done some fancy footwork and doubled the amount of subscribers supported.”

Nortel recently conducted tests of the new technology in its labs in Ottawa and is looking to commercialize the technology in future WiMAX releases. Nortel unveiled its MIMO base station earlier this month at WiMAX World, claiming it is the only carrier to have a system fully ready for the WiMAX Forum’s second wave of certification next year.