BS ISO 18197:2015 pdf download

BS ISO 18197:2015 pdf download.Space systems — Space based services requirements for centimetre class positioning
1 Scope
This International Standard defines the requirements for the wide area centimetre class positioning system by broadcasting augmentation data through satellites as follows.
— Centimetre class positioning
According to the progress of requirements for positioning services such as automatic farming, mapping and others, centimetre class positioning is very useful.
— Wide area positioning
It is quite effective to broadcast augmentation data through satellites for users over wide area such as a square, more than 1,000 km each side, anytime and anywhere. Even if this area is short of data network, additional ground network facilities are not needed. In addition, as ranging signal and augmentation data can be received from satellite broadcasting at the same time, it is unnecessary for user terminals to receive the signal such as transmitted by ground network.
— Real-time property
The user terminals need to resolve the ambiguity in real-time, using augmentation data broadcast from satellites or other means, for the realization of centimetre class positioning. On the other hand, the provider sides have to broadcast augmentation data such that the terminal sides are able to
resolve the ambiguity in real-time.
2 Normative references
No normative references cited in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 fixing
determining the integer number of carrier phase waves when calculating the position by use of carrier phase measurement
Note 1 to entry: This should be distinguished from the case of determining the desired value by convergence of continuous quantities when calculating the position by use of pseudorange measurement.
3.2 sustainability
measurement anomaly at some reference point should make no influence on the augmentation data generation
This typical system is configured mainly by the following components:
a) GNSS;
b) augmentation satellites;
c) augmentation satellites control stations;
d) ground reference points;
e) positioning augmentation centres;
f) user terminals.
Each component is explained below.
5.2 Classification of augmentation satellites
An augmentation satellite broadcasts augmentation data, uplinked from the positioning augmentation centres for users over wide area. Augmentation satellites are classified into the following:
a) geostationary earth orbit satellite (GEO);
b) inclined geosynchronous satellite orbit (IGSO);
c) medium or low earth orbit satellite (MEO/LEO).
The overview and features of various augmentation satellites is shown in Table 1.
5.3 Positioning augmentation centres
The augmentation centres make augmentation data using the observation data at the ground reference points. The system sustainability is taken into account when making augmentation data. Some remarks are described below about the functions and conditions, message structure, and user operational support service.