09 May Ground infrastructure & spectrum access
Note this issue is covered in part within the ASA Communication Technologies and Services Roadmap 2021–2030.
Challenge
The ability to communicate with satellites and downlink data is vital to the growth of the Australian space sector. Without sufficient spectrum and the capacity to downlink large amounts of data many of the emerging growth areas in the space and spatial domain will be significantly constrained. Australia needs to ensure that its companies have reliable access to spectrum and suitable ground infrastructure for data downlinks to maximise the growth of the Australian space sector.
Space spectrum is an increasingly precious commodity that is being challenged on a number of fronts even as the demand for space spectrum is growing significantly. Atmospheric water vapour causes signal attenuation which generally increases with frequency requiring higher power transmitters and better receivers to maintain link margins. C-band spectrum was chosen for GEO satellite links as an optimum spectrum/power trade-off, but C-band is highly desired by
the terrestrial mobile phone industry. The potential to generate high license fees from the mobile phone industry prompted the US FCC to move satellites out of most C-band spectrum in the
US and the rest of the world is likely to follow. There is a growing issue of how to value satellite spectrum across all relevant satellite bands to ensure it is maintained for growing satellite services in the face of potentially higher spectrum license revenues available from the growing mobile phone industry.
At the same time the significant growth in satellites is creating challenges for new operators to find spectrum for their services without interfering with existing systems. This is particularly acute in LEO with ever increasing satellite constellations and has resulted in both ground and space-based systems which inhibit transmission at times to avoid interference such as when in line of site of GEO satellites. Another emerging challenge is finding spectrum to maintain communications with the growing bandwidth needs of spacecraft in cis-lunar and trans-lunar orbits associated with the return to the Moon without affecting the communications capability and growth of satellites in LEO, MEO and GEO orbits around Earth.
Spatial satellites are not only growing in number but also in sophistication of sensors which are producing increasing amounts of data. This higher fidelity data enables more sophisticated analysis but requires significantly more bandwidth to downlink the information. There is a risk
that much of this useful data will be lost without the ground infrastructure and spectrum to enable these higher bandwidth downlinks.
OPPORTUNITY FOR GROWTH
The challenges of accommodating more satellite systems within existing satellite spectrum as well as finding spectrum for the increasing amounts of data to be downlinked is driving significant development activity. Australia has world class capability in ground infrastructure and has opportunities as a location for ground networks for high volume data downlinks. Australia is well located geographically as a downlink site for spatial data downlinks from LEO satellites passing over Asia as well as offering an alternate site for data downlinks from Europe and North America. Australia’s wide geographic footprint offers the opportunity for eastern and western ground network sites that can capture more LEO satellite passes for downlinks. Spectrum congestion is leading to development of additional bands such as V-band as well as the use of optical links where Australia has significant capability. Development of new waveforms to enable shared spectrum and on-board satellite processing to minimise data downlink size are other growth areas where Australia has expertise.
ACTIONS
1. Create strong information campaign to raise awareness across all government departments of the critical strategic importance of satellite spectrum for the space and spatial industry and how erosion of satellite spectrum will reduce the availability of space and spatial services for their department. This information campaign needs to be of sufficient size to counterbalance the ongoing appeals for access to satellite spectrum by the mobile phone industry. This awareness campaign needs to make a compelling argument that spectrum for the space and spatial industry is of critical importance even though it might not generate the type of revenue that the mobile phone industry might pay for spectrum licenses, at least in the short to medium term.
2. Australia should play an active role in international fora to preserve key spectrum for space and spatial activities including in higher spectrum bands and for optical links.
3. Explore all opportunities for Australia to provide high speed data downlink sites for space and spatial data particularly for high data downlinks from Asian, European and American satellites. Regional and international spatial fora as well as commercial operators should be made aware of the benefits of data downlink infrastructure in Australia.
4. Encourage and support Australian development of waveforms and spectrum sharing techniques as well as on-board processing techniques to maximise the downlinking of essential data.
5. Encourage and support Australian development of optical downlink capabilities and infrastructure as well as exploration of higher RF bands such as V-band (40–70 GHz) and E-band (70–90 GHz).