38
Chapter 5
attract the highest prices, when it satisfies all the information requirements
of an operational user.
Figure 1 illustrates the Information Delivery System in more detail. On
the left side of the diagram raw data is downlinked from the spacecraft and is
stored in an archive. The process of conversion of these data into useful
information can be divided into two steps, which we will designate here as
“Pre-processing” and “Data to Information Conversion”. The latter is
sometimes referred to as the “value added” step.
2.1
Pre-processing
The pre-processing step is concerned with the conversion of raw data
received from a sensor into accurately calibrated, accurately located physical
variables such as reflectance, emittance, backscatter, temperature, etc. For a
given sensor, the output of this step is a representation of the spatial
distribution of a certain physical variable over a segment of the Earth system
at a particular point in time. It is important that the pre-processing step be
executed in a way which leads to a result which is as quantitatively accurate
as possible, both in magnitude of the measurement and its location. There
are several reasons for this: Firstly, true understanding of physical and
biological processes within the Earth system comes from our ability to
model these processes and understand the differences and similarities
Chapter 5
attract the highest prices, when it satisfies all the information requirements
of an operational user.
Figure 1 illustrates the Information Delivery System in more detail. On
the left side of the diagram raw data is downlinked from the spacecraft and is
stored in an archive. The process of conversion of these data into useful
information can be divided into two steps, which we will designate here as
“Pre-processing” and “Data to Information Conversion”. The latter is
sometimes referred to as the “value added” step.
2.1
Pre-processing
The pre-processing step is concerned with the conversion of raw data
received from a sensor into accurately calibrated, accurately located physical
variables such as reflectance, emittance, backscatter, temperature, etc. For a
given sensor, the output of this step is a representation of the spatial
distribution of a certain physical variable over a segment of the Earth system
at a particular point in time. It is important that the pre-processing step be
executed in a way which leads to a result which is as quantitatively accurate
as possible, both in magnitude of the measurement and its location. There
are several reasons for this: Firstly, true understanding of physical and
biological processes within the Earth system comes from our ability to
model these processes and understand the differences and similarities