The demonstration at its Munich laboratories on Tuesday reached speeds of 1GB per second, 20 times faster than 802.11g, thanks to a combination of new OFDM techniques and multi-in, multi-out (MIMO) antenna technology.
The company had demonstrated the new modulation schemes without MIMO in September with speeds of up to 360MB per second. The demonstration system runs in the 5GHz band and uses a bandwidth of 100MHz, roughly three times the bandwidth of an 802.11g channel. This makes the Siemens system around seven times more efficient than the best of today's wireless networks.
"Future mobile communication systems will have to utilize the frequency band as efficiently as possible, with the lowest possible transmit power," Christoph Caselitz, president of the Mobile Networks Division at Siemens Communications, said in a prepared statement. "With our experimental system, we've been able to demonstrate how powerful intelligent antennas can be in combination with OFDM. In doing so, we've created a major module for future mobile communication systems."
MIMO systems increase throughput by creating multiple channels distinguished by the different time delays between the various antennas. The Siemens system used three for transmission and four for reception, roughly trebling throughput from the previous demonstration. Although MIMO systems have been tested in laboratories for a few years, their use in commercial systems has been limited due to the high level of computation required. Siemens claim to have reduced this by using more efficient algorithms. OFDM (orthogonal frequency division multiplexing)is already in use for digital radio and television transmissions and ADSL, and is likely to be part of at least one ultra wideband standard.
The company will not predict when this technology will be commercially available, but says that by 2015, user requirements for bandwidth will have risen by a factor of 10.
Rupert Goodwins of ZDNet UK reported from London.