IFC27/2011 - Submission by Bureau of Meteorology
Bureau of Meteorology Comments on the ACMA Paper:
Earth station siting – Guidance on the establishment of new Earth stations and other space communications facilities or the expansion of existing facilities
19 October 2011
Contact: Paul Hettrick
Observations and Engineering Branch
PO Box 1289
Melbourne VIC 3001
Ph: 03 96694240
Email:
1. Background Information
The Bureau utilises many Earth Observations resources in the fulfilment of its responsibilities under the Meteorology Act (1955), and more recent roles mandated by the Federal Government. The Bureau, along with all other meteorological agencies around the world, is experiencing an increase in responsibilities and expectations, particularly for the long-term global monitoring of Earth’s environment,and for increasingly high-resolution near-term forecasts and severe weather warnings. The Bureau provides this information to the public, private industry, and all levels of government for a wide range of usesincluding safety-of-life, asset protection, primary production, infrastructure planning and management, and natural and industrial resource management.The Bureau’s fulfilment of these and other functions necessitates the availability of real time observations from present and future remote sensing systems.
Information about the atmosphere,land and ocean is received directly by Bureau Earth stations from both low-earth orbit (LEO) and geostationary meteorological satellites using communications downlinks in the 1675-1710 MHz (L-band) and 7750-7850 MHz and 8025-8400 MHz(X-band) Meteorological Services and EESS allocations.The continued availability of direct reception in these bandsis essential for the Bureau’s operations into the future.
The location of Bureau earth stations for tracking LEO satellites is constrained by the required north-south and east-west coverage while the satellites are in view above the horizon (within line-of-sight) of a given receiver.The area of coverage required, to meet the Bureau’s national and international obligations, extends across the continent and the surrounding ocean areas for which the Bureau has mandated responsibility, including to Antarctica in the south. This imposes a requirement for some earth stations to be located close to the seaboard in strategic locations.
2. Specific Comments
3. The ACMA seeks comment on areas of growth in the satellite industry. Where is the biggest growth expected? Are there any emerging applications for satellite services that are expected to impact spectrum requirements?
Continuing advancement of remote sensing payloads on satellite platforms is leading to larger data sets which require higher data transmission rates. This is consistent with the growing demand for high spatial resolution and hyperspectral data to meet government and community needs for severe weather warnings and high resolution environmental analysis and forecast products. The current trend for meteorological and environmental satellites is to move to the X-band region of the microwave spectrum. A number of US and Chinese satellites already provide direct broadcast at these frequencies. It is anticipated that from 2013 the US polar-orbiting operational satellite program, which is of vital importance to the Bureau, will only provide direct broadcast transmissions in X-band[1]. Therefore, ongoing access to this part of the spectrum is of great concern to the Bureau. (See response to Issue 11below.)
5. The ACMA seeks stakeholder comment on any additional categories of tools that could be used to address the various pressures on spectrum used by the satellite and space sectors.
Genuine consideration needs to be given to the value of public goods contributed through the Bureau’s services to the Australian community and their economic impacts as well as their contribution to the protection of life and property. The Bureau has a responsibility to provide services for the public good. These services include using satellite resources to monitor severe weather, and for ingestion into atmospheric models which in turn contribute to weather forecasting products that are widely used in routine decision making by industry. The quality of weather forecasting in severe weather situations and the release of warnings impact the protection of life and property. Such safety considerations need to be incorporated in addition to economic, technical and planning measures.
6. The ACMA seeks comment on using opportunity-cost pricing of spectrum for satellite Earth station licensing based on spectrum denial caused to terrestrial services.
The overarching argument put forward in this discussion paper by the ACMA for removing earth stations from populated areas is based on the concept of ‘denial of spectrum’ to anticipated future demand for fixed and mobile wireless broadband services, and to Electronic News Gathering (ENG) systems. Spectrum denial is then associated with the economic concept of ‘opportunity cost’ of spectrum which is then used to support an argument in favour of projected future commercial use of the spectrum in question. This economic argument focuses solely on the ability to value the spectrum for commercial purposes and does not take into account or even seek to mention the economic benefits (past, present and future) arising from the incumbent users of this spectrum, including the Earth Observations community.
A balanced discussion paper should seek to understand and present the economic benefits and derived community value of current uses of this spectrum, just as this paper seeks to present the value (through anticipated demand) of the spectrum as it would be utilised by the telecommunications industry to provide wireless data and telephony services. In order to deliver public good services that deliver both direct economic value and that inform critical decisions regarding safety of life and assets, Earth observations organisations will continue to rely heavily on direct communications links with both geostationary and non-geostationary satellites. The associated utilisation of passive sensing bandsmust also be considered in light of the band-specific issues raised in section 4.1 of the discussion paper, and for which comments are offered in the discussion of Issue 11 below.
Assertions made in the statement“With the ever-growing web of optical fibre backhaul available, traditional arguments about the need to establish or preserve satellite and space gateway facilities in populous areas no longer hold.” are not qualified with timeframes, fibre infrastructure routes (existing or planned), or data transmission costs. Because “Australia is a vast land mass with an unevenly distributed population.” fibre links are also likely to be unevenly distributed, and vast areas will still remain uneconomical to route such links to. The only way they could become economical would be for users to be charged at a considerable premium, or for the costs to be subsidised.The provision of redundancy via an alternative high-bandwidth communications path such as a different fibre link would again increase costs. Data transmission costs coupled with initial and ongoing infrastructure and maintenance costs would most likely make the establishment and operation of remote satellite parks prohibitively expensive for all but commercial organisations that can pass the costs on to customers. The Bureau and other non-commercial government, academic and research organisations are not in the position to use this mechanism to recover costs beyond a certain level. The Bureau’s basic service obligations to the community are recognised as economic public goods and it is not feasible to recover the costs.
The Bureau’s satellite data reception needs continue to provide reasons for reception sites to be located, not necessarily within, but in close proximity to populous areas. Satellite reception locations for LEO spacecraft are geographically distributed to ensure adequate sampling of the Earthand within the Australian region. Factors involved in such decisions involve:
- accommodation of physical limitations of LEO instruments, i.e. extent of coverage is dependent on geographic location of data reception site,
- consideration of dominant meteorological conditions and their location and extent, and
- proximity of a satellite data reception site to maintenance staff for provision of failure rectification in a timely manner (<1.5 hours).
The above factors lead to siting requirements where multiple sites are necessary in Australia (not just single sites on the west coast and east coast) and in most cases those sites must be within a reasonable proximity to populous areas.
For LEO satellites, timeliness can only be guaranteed by direct reception, as the current alternative is to wait for the data to be transmitted to the satellite operator’s ground station (which is only periodically visible to the satellite) and then distributed via the internet. This adds a considerable delay that quickly reduces the value of the data in question. Fibre links from remote Earth stations would of course support the required data rates, but is a cost that is currently non-existent in the Bureau’s budget, and which is unlikely to be serviceable along with all the other costs noted above, without a major policy change at the Federal Government level.
10. The ACMA seeks comment on all matters related to site interference protection.
While terrain shielding can be used successfully in many satellite reception configurations involving mainly geostationary orbits, it is a significanthindrance for tracking LEO satellites. The extent of swaths that satellites can sense during a pass is related to the length of time aLEO satellite is in the direct line-of-sight of the receiving station. This time is reduced by obstructions such as trees, hills, buildings, mountains and other obstacles obscuring the horizon. This means that for LEO satellites, terrain shielding is not a viable option.[2]
11. The ACMA seeks comment on issues raised in the band-by-band analysis chapter, particularly comments on specific frequency bands. Do you agree with the analysis? Why or why not?
The 1400-1427 MHz and 2690-2700 MHz bands listed in the discussion paper as being candidates for active (fixed or mobile) services are dedicated passive sensing bands as noted in the Radio Regulations Table of Allocations. Any deployment of active services in these bands is in contravention of the Radio Regulations. Passive sensing bands are used to measure the “fingerprints of nature” –molecular resonant frequency ranges that are fixed by nature. Any artificial emissions into these bands above the thermodynamic noise floor will contaminate the measurements and lead toloss of information, potentially to the level of effectively blindingsatellite sensors over large parts of the Earth’s surface.
The pressure to meet demand for spectrum by proponents of wireless broadband, IMT and ENG systems should not lead to a reduction or relaxation in equipment standards for filtering of transmitters. This is necessary toensure that their out-of-band emissionsare within internationally agreed limits for adjacent passive EESS bands. The onus for controlling OOB emissions lies solely with the owners of the active systems in question and should be a mandatory requirement of the associatedlicences.
Section 4.1.21400-1427 MHz
This passive band is used for salinity and soil moisture sensing. The ACMA discussion paper states:“...continued protection against out-of-band emissions from future fixed or mobile services, except within the RQZ, may not be able to be supported.” Contamination of this band by emissions from fixed and/or mobile services is not acceptable and is in contravention of the Radio Regulations Table of Allocations for all regions.An example of a recently launched (2009) satellite that uses this band is SMOS[3]. SMOSwas developed as a direct response to the current lack of global observations of soil moisture and ocean salinity which are needed to further our knowledge of the water cycle, and to contribute to better weather and extreme-event forecasting and seasonal-climate forecasting. Measurements made during the commissioning phase revealed contamination by man-made in-band emissions over large areas of southern Europe, southern and eastern Asia, the Middle East and northern Africa (figure 1). Considerable effort and cooperation between ESA and European spectrum regulators has led to a significant reduction in interference in this region[4].
Due to the ACMA’s diligence, Australiaisshown to be effectively free of man-made interference in this passive sensing band. The Australian remote sensing community and international users of this datatrust that the ACMA will continue to recognise the importance of keeping it uncontaminated.
Section 4.1.6 1610-1930 MHz
Within this frequency range, the 1675-1710 MHz band is of major importance to the meteorological and Earth sensing community for LEO and geostationary satellite downlinks, and for use under the Meteorological Aids (MetAids) classification. MetAids includes systems such as radiosondes and radiotheodolites. Further discussions need to reflect this dependency, and this band needs to be given special attention when considering spectrum allocations that can lead to interference to ground stations and MetAids systems.
Section 4.1.102690-2700 MHz
This passive band is used for salinity and soil moisture sensing. The ACMA discussion paper states as a foregone conclusion that IMT will be deployed in this band, as indicated by the sentence: “Operations in this band at Parkes and Narrabri may need to be reviewed once IMT deployments commence”. Contamination of this band by emissions from IMT fixed and mobile components is not acceptable and is in contravention of the Radio Regulations Table of Allocations for all regions.
Section 4.1.13/Section 4.1.147250-7850 MHz and 8025-8400 MHz (X-Band)
The X-band is used for direct reception of meteorological data from LEO satellites owned by other countries, including the US (Aqua, Terra), and China (Feng Yun series). The expected increase in data volume from non-geostationary MetSat applications is reflected in Agenda item 1.24 for WRC-12:to consider theexisting allocation to the meteorological-satellite service in the band 7 750-7 850MHz with a view to extending this allocation to the band 7 850-7 900MHz, limited to non-geostationary meteorological satellites in the space-to-Earth direction, in accordance with Resolution672(WRC07). This 50 MHz extension is necessary to accommodate satellites planned to be launched in the timeframe 2017–2020.Access to the above frequency bands from sites with the required line-of-sight coverage of LEO satellites will therefore remain essential for meteorological and Earth exploration satellite communications for the foreseeable future.
12. The ACMA seeks comment on issues raised in the site-by-site analysis. Do you agree with the analysis? Why or why not?
The statement in section 5.6, that “No significant facilities appear on the ACMA register in Victoria” is of concern to the Bureau, since the Bureau’s Satellite Earth station at HMAS Cerberus is of great importance to the Bureau’s satellite data reception capabilities and is as such, significant in national terms. The table in Appendix A does however list the Bureau’s Earth stations and affiliated/joint reception facilities.
16. The ACMA seeks comment on all issues surrounding the development and establishment of an east coast satellite park, particularly on what factors would be necessary to make it an attractive option for Earth station location.
A preliminary analysis of the proposed site at Quirindi, NSW, indicates that the surrounding landscape obscures the horizon below an elevation of 9°-12°. This has a significant impact on the coverage provided by LEO satellites. The dashed lines in figure 2 show the possible coverage of LEOsatellites at the proposed site, where the horizon is obscured below 9 degrees (outer line) and 12 degrees (inner line). As is evident, the area of coverage is considerably reduced in comparison to the current coverage afforded by the Bureau’s Satellite Earth station at HMAS Cerberus. In particular, the region south of the Australian continent, which is of great meteorological importance to the south east of Australia, would not be covered by a LEO Earth station atQuirindi. The Bureau notes the ACMA’s qualification that the Liverpool Plains area where Quirindiis located is unlikely to be used for a satellite park due to uncertainty over future land use, however, the horizon analysis is of course applicable to any proposed site.
20. The ACMA seeks comment on any other issues regarding Earth station and space communication facility siting that should be considered.
As outlined in the background information in section 1 above, the Bureau has many responsibilities to the Australian public as defined bythe Meteorology Act (1955), as well as to the international meteorology community. The quality of the Bureau’s outputs can impact the safety of life and property. In order to continue to provide a high level of service to the community, the Bureau relies on an uninterrupted supply of vital data, including data provided by satellites through direct reception. When considering regulation of Earth Station siting, the ACMA must give due consideration to the value of provision of services for the public good as well as the economic and human impact if those services are hindered.
Figure 1- Contamination of SMOS soil moisture measurements by in-band and possibly some out-of-band emissions during its commissioning phase. ()
Figure 2 - Geographic coverage for low orbit satellites at the proposed east coast site at Quirindi (dashed lines) in comparison with the current extent provided by the Bureau's HMAS Cerberus reception site (solid line).
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[2]An example is provided in theresponse to item 16.
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