Australian Centre for Space Photonics Andrew McGrath Anglo-Australian Observatory

This Presentation Interplanetary communications problem Long term solution Historical Australian involvement Further Australian involvement Making it happen

Exploration of Mars Highlights the communications problem Long term and substantial past and continuing international investment

Exploration of Mars 1960 Two Soviet flyby attempts 1962 Two more Soviet flyby attempts, Mars Mariner 3, Zond Mariner 4 (first flyby images) 1969 Mariners 6 and Mariners 8 and Kosmos 419, Mars 2 & Mars 4, 5, 6 & 7 (first landers) 1975 Viking 1, 1976 Viking 2

Exploration of Mars 1988 Phobos 1 and Mars Observer 1996 Mars Mars Pathfinder, Mars Global Surveyor 1998 Nozomi 1999 Climate Orbiter, Polar Lander and Deep Space Mars Odyssey

Planned Mars Exploration 2003 Mars Express 2004 Mars Exploration Rovers 2005 Mars Reconnaissance Orbiter Scout Missions Smart Lander, Long Range Rover 2014 Sample Return

Interplanetary Communication Radio (microwave) links, spacecraft to Earth Newer philosophy - communications relay (Mars Odyssey, MGS) Sensible network topology 25-W X-band (Ka-band experimental) <100 kbps downlink

Communications Bottleneck Current missions capable of collecting much more data than downlink capabilities (2000%!) Currently planned missions make the problem 10x worse Future missions likely to collect ever- greater volumes of data

Communications Bottleneck Increasing downlink rates critical to continued investment in planetary exploration

Communications Bottleneck NASA's perception of the problem is such that they are considering an array of 3600 twelve-metre dishes to accommodate currently foreseen communications needs for Mars alone

Communications Energy Budget Consider cost of communications reduced to transmitted energy per bit of information received

Communications Energy Budget information proportional to number of photons (say, 10 photons per bit) diffraction-limited transmission so energy density at receiver proportional to ( R/D T ) -2 received power proportional to D R 2 photon energy hc / So: Cost proportional to R 2 / (D T 2 D R 2 ) Assumptions:

Communications Energy Budget Cost proportional to R 2 / (D T 2 D R 2 ) X-band transmitter ~ 40 mm Laser transmitter ~  m Assuming similar aperture sizes and efficiencies, optical wins over microwave by > 3 orders of magnitude

Long-term Solution Optical communications networks Advantages over radio Higher modulation rates More directed energy Analagous to fibre optics vs. copper cables

Lasers in Space Laser transmitter in Martian orbit with large aperture telescope Receiving telescope on or near Earth Preliminary investigations suggest ~100Mbps achievable on 10 to 20 year timescale Enabling technologies require accelerated development

Key Technologies Suitable lasers Telescope tracking and guiding Optical detectors Cost-effective large-aperture telescopes Atmospheric properties Space-borne telescopes

An Australian Role - till now History of involvement Launch sites Development of early satellites Communications –Deep Space Network –Parkes, ATNF –Continuing involvement

An Australian Role - in the future Australian organisations have unique capabilities in the key technologies required for deep space optical communications links High-power, high beam quality lasers Holographic correction of large telescopes Telescope-based instrumentation Telescope tracking and guiding

The University of Adelaide Optics Group, Department of Physics and Mathematical Physics –High power, high beam quality, scalable laser transmitter technology –Holographic mirror correction –Presently developing high power lasers and techniques for high optical power interferometry for the US Advanced LIGO detectors

Anglo-Australian Observatory Telescope technology Pointing and tracking systems Atmospheric transmission (seeing, refraction) Cryogenic and low noise detectors Narrowband filter technology

Macquarie University Centre for Lasers and Applications – Optical communications –Transmitter technology

A Proposal Use the ARC 'Centre of Excellence' programme to link these organisations to capitalise on Australia's strategic advantages to become an indispensable partner in the world-wide scientific space exploration effort

Australian Centre for Space Photonics To expand unique Australian capabilities and experience to progress research into key technologies for an interplanetary high-data rate optical communications link that are synergistic with near term space communication needs.

Australian Centre for Space Photonics Manage a portfolio of research projects in the key technologies for an interplanetary optical communications link Work in close collaboration with overseas organizations such as NASA and JPL

An Australian foothold into the well- established `big science' investment of the leading space agencies Australian Centre for Space Photonics

Closer ties to leading space agencies and their current and planned missions Australian Centre for Space Photonics

Australia's continued long term participation in the Deep Space Network Australian Centre for Space Photonics

Attract and retain the best Australian students and staff in optics and photonics Australian Centre for Space Photonics

Creation of photonics and space technology IP for commercial development Australian Centre for Space Photonics

Take advantage of unique Australian capabilities Australian technology becomes critical to deep space missions Continued important role in space FOR MORE INFO... Australian Centre for Space Photonics