This paper describes the design, installation and operation of a high-speed, real-time coral reef observing system network at Heron Island, within the Australian Great Barrier Reef. As part of the Queensland Integrated Marine Observing System (Q-IMOS) node of the Australian Integrated Marine Observing System (IMOS), a low data rate wireless sensor network has been operational at Heron Island since 2008. In 2013 a new surface reef pole and underwater cabled Ethernet network were installed on the edge of the Heron Island Reef lagoon, with telemetry back to the Heron Island Research Station achieved using a 300 Mbps wireless 802.11 link. The reef pole provides a network bridge to an underwater-cabled Ethernet network, and also provides an 802.11 wireless access point for the remainder of the Heron Island reef lagoon. Internet protocol networks provide for an extensible architecture, enabling the easy connection of any type of oceanographic instrument, camera or video system to the observing system. Acoustic monitoring receivers for fish tracking are connected to the network to allow for real-time monitoring. The underwater-cabled network is modular in design allowing for easy repair, expansion or reconfiguration of the network for any future requirements. This paper discusses the design considerations, system components and results of using affordable wireless 802.11 networks in a harsh marine environment for coral reef observing systems.

This paper describes the implementation and subsequent performance of an over-the-horizon microwave link operating over seventy kilometres of ocean between the Australian mainland and Davies Reef, an offshore site within the Australian Great Barrier Reef. The outer sections of the Great Barrier Reef are not widely covered by cellular mobile networks with the only alternative being satellite telemetry, which becomes prohibitively expensive with high volume data such as images and video. A microwave radio link operating at a frequency of 10.5 GHz uses the ocean evaporation duct to propagate radio signals far beyond the optical line-of-sight limitation. While a ducted microwave link had previously been established at this site using commercial microwave equipment, the power requirements of this system proved to be unsustainable in the long-term. Advancements in technology for low-cost, Wireless Internet Service Provider equipment have allowed a system to be deployed which is both economical and has low power consumption, making it ideally suited for remote sites operating on solar power. Due to the lower cost of both the telecommunications equipment and the power system required, it now becomes feasible to deploy networks of monitoring stations linked by microwave systems taking advantage of evaporation duct propagation. The success of this link will open opportunities for high bandwidth linkages supporting a range of remote observation systems, including video, which will improve our understanding of this large complex eco-system.