Wireless network smashes world speed record

Wireless network smashes world speed record

A new world record has been set for transmitting data across a wireless network, claim researchers in Germany.

A team at Siemens Communications research laboratory in Munich, have transmitted one gigabit (one billion bits) of data per second across their mobile network. By contrast, the average wireless computer network can send only around 50 megabits (50 million bits) of data per second.

The researchers used three transmitting and four receiving antennas and a technique for boosting the amount of data that can be sent wirelessly, called Orthogonal Frequency-Division Multiplexing (OFDM), to set their record.

"With our experimental system, we've been able to demonstrate how powerful [multiple] antennas can be in combination with OFDM," says Christoph Caselitz, president of the Mobile Networks Division at Siemens Communications. Caselitz estimates that wireless networks will be expected to cope with 10 times as much data by 2015.

Avoiding interference

"Future mobile communications systems will have to utilise the frequency band as efficiently as possible," Caselitz adds. This means using the lowest possible transmit power to keep phone devices from running down, he explains.

Frequency-division multiplexing involves simultaneously sending multiple signals over different frequencies between two points. The technique can be prone to interference between different signals.

But OFDM splits carrier signals into smaller sub-units which are synchronised to reduce interference. The technique has already been implemented in some wireless computer networks and digital television broadcasting systems.

Recombining smaller signals in real time, however, requires considerable computing power. So the Siemens team developed new computer algorithms in order to send more data using existing hardware.

The speedy OFDM network was developed in cooperation with the Heinrich Hertz Institute and the Institute for Applied Radio System Technology, both in Germany. It will be demonstrated at the 3GSM World Congress in February, 2005.