Radio makes cords obsolete

New research at the Georgia Institute of Technology could soon make that tangle of wires under desks and in data centres a thing of the past.

Scientists at the Georgia Electronic Design Centre (GEDC) at Georgia Tech are investigating the use of extremely high radio frequencies to achieve broad bandwidth and high data transmission rates over short distances.

Within three years, this 'multi-gigabit wireless' approach could result in a multitude of PAN applications, including next-generation home multimedia and wireless data connections able to transfer an entire DVD in seconds, they claim.

The research focuses on RF frequencies around 60 GHz, which are currently unlicensed in the US. GEDC researchers have already achieved wireless data-transfer rates of 15 Gbps at a distance of 1 m, 10 Gbps at 2 m and 5 Gbps at 5 m.

"The goal here is to maximise data throughput to make possible a host of new wireless applications for home and office connectivity," said Prof Joy Laskar, GEDC director and lead researcher on the project along with Stephane Pinel.

"GEDC's multi-gigabit wireless research is expected to lend itself to two major types of applications, data and video," said Pinel, GEDC research scientist.

Very high speed, peer-to-peer data connections could be available in under two years, according to Pinel.

Devices such as external hard drives, laptop computers, MP3 players, mobile phones, commercial kiosks and others could transfer huge amounts of data in seconds. And data centres could install racks of servers without any wires.

"Our work represents a huge leap in available throughput," Pinel said.

"At 10 Gbps, you could download a DVD from a kiosk to your mobilephone in five seconds, or you could quickly synchronise two laptops or two iPods."

The input-output (I/O) system of current devices cannot approach such speeds. Moreover, Pinel said, users of multi-gigabit technology could wirelessly connect to any device that currently uses Firewire or USB.

Currently, Pinel said, the biggest challenge is to further increase data rates and decrease the already-low power consumption, with a goal to double current transmission rates by next year.

GEDC researchers are pursuing this goal by modifying the system architecture to increase intelligence and effectiveness in the CMOS RF integrated circuits that transmit the data. The researchers are using computer-aided design tools and test-bed equipment to recalibrate system models and achieve the desired improvements in speed and functionality.

Investigators are placing special emphasis on implementing an RF concept called single-input-single-output/multiple-input-multiple-output, which enables ultra-high data throughput. At the same time, they seek to preserve backward compatibility with WLAN 802.11, the Wi-Fi standard used in most wireless LANs.

Even when sitting on a user's desk, Pinel stresses, a multi-gigabit wireless system would present no health concerns. For one thing, the transmitted power is extremely low, in the vicinity of 10 mW or less. For another, the 60 GHz frequency is stopped by human skin and cannot penetrate the body.

The fact that multi-gigabit transmission is easily stopped enhances its practicality in an office or apartment setting, he adds. The signals will be blocked by any wall, preventing interference with neighbours' wireless networks.

Currently, there are no world standards in this bandwidth, explains GEDC director Laskar. To address the situation, representatives of the ECMA International computer-standards organisation met at GEDC to discuss a new international 60 GHz standard.

The IEEE, international association of electrical engineers, is also weighing a 60 GHz standard, to be called 802.15.3C.

Laskar believes that additional applications will emerge as multi-gigabit technology becomes standardised and gains maturity.