Telemetry

Oceans 2025 Theme 8, work package 8.6

Themes 1, 3 and especially Theme 10 will use remote instrument control and continual data supply (to near-real-time Web display) from: coastal gauges for sea level, tsunami; deep-sea pressure for ocean circulation; sea-bed or moored instruments for currents etc. in the ocean interior and the POL Coastal Observatory. Large data volumes can easily be handled via broadband. Duration of the deep-ocean POL lander MYRTLE can be increased to ten years use BGAN retrieval. Broadband systems will deliver fast sampling in near-real-time, allowing monitoring of short-period events, e.g. tsunami, interrogation for assimilation in forecast models, rigorous tests of models, better reliability by fault diagnosis and rectification, remote-controlled sampling and less use of ships.

Hence the objective is to design, construct and implement systems for data telemetry from remote locations: coasts, deep-sea (bed and moorings).

Approach

POL will develop new telemetry systems based on BGAN (Broadband Global Area Network; Inmarsat) and build on current developments using Broadband, Orbcomm, Iridium and Meteosat / GOES-based satellite systems. Broadband technology enables continuous data transfer over the Internet, even from remote locations (e.g. Antarctic, South Atlantic islands) independent of local infrastructure. For a dispersed sensor network, it enables high-speed two-way communications, continuous availability and removal of timing errors using Internet time servers.

Application

POL uses Orbcomm telemetry extensively in high profile projects, e.g. the Coastal Observatory (Liverpool Bay with Web display) and two remote sea level stations in the South Atlantic. Meteosat DCP systems are used for two stations in Mozambique. Faster data rates will benefit telemetry especially from ADCPs via surface buoys. The deep-ocean long-term POL lander MYRTLE (Multi Year Return Tidal Level Equipment) has four years duration using Orbcomm data capsules released to the surface annually. We plan ten years duration using BGAN to retrieve the larger data sets. For shorter-term deployments, e.g. in remote ocean areas, the low-cost POL Microlander sensor platform will be developed to use satellite telemetry.

Broadband, BGAN and Iridium fast (e.g. 1-min. to 1-sec.) near-real-time sampling will allow:

• monitoring of short-period events, e.g. tsunami, seiche
• multi-variable recording (including meteorology, near-surface fresh water)
• interrogation for assimilation in forecast models
• better reliability by fault diagnosis via two-way telemetry
• sampling intervals that can be altered remotely
• reduction in ship-time for offshore deployments and recoveries.

POL sea-level recorders in the South Atlantic

Coastal Observatory monitoring sites and locations

Outline plan

Telemetry		2007	2008	2009	2010	2011
Land-based	BGAN study, draft system, UK prototype	Y
(tide gauge / tsunami)	Compare other systems, use improved		Y	Y
	BGAN at OdinAfrica sites		4	continue	upgrade	upgrade
Buoys	Orbcomm telemetry prototype & sub-surface	Y
MYRTLE long term lander	assembly, tests	Y
	one year deployment		Y
	Telemeter stored data, recover lander			Y
	Telemetry choice for long-term transmission			Y
	Start 2-year deployment (one capsule)		Y
	Interrogation throughout 2-year deployment
	release capsule, data; recover lander					Y
	Evaluate, plan long-term test					Y

Team

Peter Foden
Geoff Hargreaves
Simon Holgate
Steve Mack
Jeff Pugh