Along the river: the stream of Earth observation

Rivers are divided into upstream, midstream, and downstream. This tripartite division also helps to understand the earth observation processing chain.

Rivers are traditionally divided into three sections along their course based on the gradient between their source and delta: upstream, midstream and downstream. This division is often used metaphorically to describe industrial value chains. 

The upstream represents the part of the value chain that is close to the source, i.e. the extraction of the required raw materials. Midstream describes important processing steps with the associated logistics. Downstream is the area closest to the end user and extends to the marketing of the manufactured products. This division is also used for the flow of Earth observation data between its source, i.e. the satellites, to its use by end users as the downstream, close to the delta of the EO stream.  

Segmenting EO into upstream, midstream and downstream can also help to better understand the objective and activities of the technology Domino-E works on. Classically, EO satellite ground segments are segmented in three parts, each one devoted to various operation steps, and thus interacting with different kinds of users.

While the downstream and midstream scopes may address different EO systems, the upstream of the ground segment is inherently mission-dependent. The upstream is tightly coupled with the satellite system and optimally set up to manage and exploit a mission supported by this system.

The observatory instrument capabilities, the specificities and features of the spacecraft specificities, and the orbits and chronologies lead to vertically dedicated upstream ground segments, even though common macro functions, often referred to as “chain”, are systematically involved:

1. The satellite Control chain: dedicated to the control of the satellite in its orbit, with a strong dependency on a given satellite platform.

2. The mission programming chain: devoted to the satellite payload tasking, i.e., the work plan management of the onboard EO instrument derived from the user’s acquisition requests.

3. The image processing chain: enabling the processing of the raw image delivered by the satellite into an elaborated image product as needed for user future exploitation in the midstream and downstream segments.

Where along this river is Domino-E?

Such vertical design has led to more or less monolithic sealed systems providing low flexibility to meet the evolution of needs in Earth observation. And this is, where Domino-E comes into play. 

Dominio-E works on the upstream area of the EO river, to stick with the metaphor of the river. The rationale is to tackle three of the current operational challenges using multiple missions for operational objectives. Therefore, three solutions will be developed. 

The first one, is a Multi-Mission Coverage Service (CS): In case of extended coverage to be performed in a given period, one satellite is often not enough to perform the task on time and on quality. DOMINO-E provides a multi-mission collaborative coverage service allowing the dynamical selection of the systems for coverage purposes and the dispatching of acquisitions on different providers/systems for site monitoring.

Secondly, a Satellite Communication and Resource Management Service (SCRMS) will be developed: Ground systems use dedicated antennas to control and command the satellite or to download the acquired images. The locations of the antenna (either owned or rented) are usually defined during the program development and maintained during the whole system life. DOMINO-E provides dynamical antenna reservation capacity (using a Ground Station as a Service – GSaaS) for the guarantee of a required downloading capacity and includes negotiation algorithms allowing the perfect value for money.

And thirdly, a Virtual Assistant Service (VAS) is among the technologies developed within Domino-E: Currently, high-level end-user needs such as “regional forest footprint evolution over the semester” cannot be automatically translated into technical terms (e.g. spectral band, sensor type, area of interest) by the system but express by an operational team of expert. DOMINO-E provides help to the end-user (who has no technical expertise in satellite or imagery) using technical, reactivity, and price criteria.

Just as the upstream segment of a river has a major influence on the midstream and downstream segments, and thus contributes to their ecological conditions, changes in the upstream part of EO have an impact on the midstream and upstream. By optimizing the upstream of EO ground segments, Domino-E contributes to the multi-mission design of future EO operations. The end users on the downstream end of this technological river will benefit from this, even if they may be a long way from the source of the EO river.

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