Ensuring the best use of spectrum

The CSIRO is using some of the latest radio technologies to ensure that the most is made of the spectrum and that users are given the high-speeds of data transmission that they want.

To meet these needs the organisation is drawing on its more than 50 years of experience in all branches of radio from propagation research to millimetric communications.

This review of the organisation's activities is based on a presentation given by Dr Alex Zelinsky at the Technology Futures Conference in Adelaide earlier this year. Dr Zelinsky is director of the ICT Centre of the CSIRO at Marsfield, NSW.

Today's wireless world consists of 2 billion mobile phone subscribers, many 3G applications, some coupled with email and video, and an expansion in Wi-Fi that looks as if it will be a major growth area in the future. HSPDA, DAB, DVB-H and WiMax are on the horizon while Mesh, RFID and ad hoc networks for transport, asset tracking and logistics are up and coming. But what are the next wireless research challenges?

The organisation's vision for the future is centred on the four areas of:

• Communications;
• Imaging;
• Sensing and positioning;
• Radioastronomy.

And this fits in well with the CSIRO's wireless capabilities that include:

1. Electromagnetics and propagation: This is necessary for understanding the air interface for wireless systems leading to the design, manufacture and testing of antenna systems and building propagation models.
2. Millimetric wave technologies that involve designing and building high-speed components for 40 to 200 GHz operation along with designing, simulating and packaging semiconductors.
3. Wireless networking that involves architecture, configuration, construction and optimisation of radio networks and then ensuring the system's capability.
4. Communications and information theory concerning signal processing, protocols, modulation and coding expertise along with design and analysis.

In other words, the organisation has a complete wireless system capability.

The finite resource of the radio spectrum is under increasing demand for services such as mobile phones, satellites and broadcasting, sensing applications such as radar, position location, radioastronomy and non-invasive scanning.

This demand is not only due to more users. It is also because there are more services and applications, there is a demand for high bandwidths and everyone wants high reliability.

The organisation's ICT Centre has been set up to look at the technological challenges of improving reliability, increasing bandwidth, reducing costs and bringing in new applications.

More efficient use of the current spectrum is one area that is being addressed as is new technology for systems at higher frequencies, new communications and new sensing applications.

Motivating all this is the goal to improve personal communications by two orders of magnitude, improve public safety for travellers and emergency services and improve health and well being.

At the moment, the spectrum above 55 GHz is not yet crowded. This gives an opportunity to provide a 100 times or more improvement on data rates compared with current WLANs. It is also suitable for fibre quality wireless connectivity and data rates of 10 Gbps or more which is one of the major goals of the CSIRO.

To provide effective and efficient antennas at these frequencies the organisation is calling on its experience in providing ground and satellite systems, including novel multi-band designs in the 2 to 30 GHz region.

This work plus a profound knowledge of indoor propagation, climatic effects and urban environments puts the organisation in the box seat to advise and carry out modelling.

Millimetre wave imaging is being increasingly adopted as a technology for seeing through fog, dust, clouds and smoke. Its applications include aircraft landing in fog, bushfire fighting and perimeter security. Current systems work in the 35 to 140 GHz bands but they need further refinement to overcome sales resistance as they are large and costly.

Wireless is also being applied to personal health. RF devices and appropriate antennas have been developed to detect heart rate and breathing and such equipment is expected to become more important as patients are increasingly monitored at home.

And finally, CSIRO has always been a major player in radioastronomy and now it is deeply involved with the huge square kilometre array that will provide 1,000,000 m2 of 'looking' power into outer space. When the system comes on line in 2020, it will be 100 times more powerful than anything we have today.