An Australia/New Zealand optical communications ground station network for next generation satellite communications

Abstract

The limited bandwidth and security provided by radio frequency communications between the ground and space can be overcome with optical communications. The smaller beam divergence and high carrier frequency increase the bandwidth and brings with it the potential of achieving a global communications network with absolute security using quantum states to transmit encryption keys, also known as Quantum Key Distribution (QKD). A drawback of ground-to-satellite optical communications, however, is that clouds provide effectively complete blockage of the beam. This can be mitigated by means of receiver site diversity, in which a network of geographically dispersed receivers provides far higher link availability. We present a proposal for a network of optical ground stations in Australia and New Zealand for optical communications to provide secure satellite links for the growing space-based market. Optical ground station nodes in the Australian Capital Territory and South Australia have been funded and are currently being planned. Partial funding for other nodes in Western Australia and New Zealand has also been achieved. Funding for infrastructure is being sought to tie these stations together to produce a world leading optical communication network. This presents an opportunity for our nations to become a space-to-ground data highway and become a leading provider of secure satellite links for a large and growing market. In order to take advantage of hardware currently in orbit and planned (including quantum communication) each network node will be capable of communications with optical and current radio-frequency methods. This has the added benefit of future proofing optical communications hardware and building industry with the accessibility of an optical ground station network.