DATA FORMAT ANALYSIS USING AUTOMATON APPROACH 
Maria Fätima Mattiello Francisco 
Rubens Cruz Gatto 
Sergio Norio Itami 
Wilson Yamaguti 
National Institute for Space Research, Ground System Division, Brazil 
Commission I, Working Group 6 
KEY WORDS: Acquisition, Data, Software, Analysis, Recognition, Format, Pattern. 
ABSTRACT 
The availability of the environmental data acquired by the increasing number of both the Data Collecting Platform networks - DCPs, 
in the Brazilian territory, and the Receiving Ground Stations has been improved for their users. It was reached through the 
development of a dedicated module in the data processing and dissemination software system SCMCD, which performs both the 
data reception automatically and the data format analysis more efficiently in the Mission Center. Because the DCP data format can 
follow different message standards, for instance, the data format standard used by the DCPs in the ARGOS system and that used in 
the METEOSAT system, it is desirable to enable the Mission Center with intelligence in order to distinguish these different formats. 
This paper presents the design and implementation of that SCMCD acquisition module which provides the Mission Center with 
event-driven procedures. In order to perform the recognition and error analysis of several formats of DCP messages and also the 
Satellite Control Center messages (orbit prediction and the status of the Ground Station receivers), the acquisition module was 
developed based on a finite state automaton approach. 
With the automaton approach, the implementation of the SCMCD acquisition module is prepared to incorporate as many different 
formats of DCP messages as the existing different types of Ground Stations working with environmental data transmission from 
DCPs. The aggregation of a new format to be processed is easy, since only the actions associated with each event must be coded. 
The state transition mechanism is already implemented by the acquisition module. It is only necessary to represent the state/event 
mapping from the automaton in form of a decision table. 
1. INTRODUCTION 
prediction data and the status of the Ground Station receivers. 
A DCP is a data collecting, formatting and transmitting device Because they are related with that satellite pass, they must be 
used in environmental monitoring applications such as stream treated together. 
flow and flood warning, irrigation control, water quality, water 
resource management, climate and air quality measurements, In the Mission Center, the software system - SCMCD is 
animal migration, etc. The data collecting function is responsible for the reception, treatment, storing and 
performed by a set of sensors which usually monitor water disseminating the environmental data (Francisco & Gatto, 
level and quality of rivers and reservoirs, air temperature and 1995). In order to support the flexibility of the environmental 
humidity, atmosphere pressure, wind speed and direction, data being received from different standards of Ground 
solar radiation, soil temperature and humidity, ozone Stations, with whatever standard format, and without 
concentration, precipitation, etc. predefined scheduling, an automatic acquisition module was 
incorporated in the software system SCMCD. The acquisition 
The acquired data, including DCP identification and status, are module was developed based on a finite automaton approach. 
stored, formatted in a standard message and sent to the satellite . 
As other satellites, the Brazilian Complete Space Mission 
(MECB) with the Data Collecting Satellites - SCD series and 2. FINITE STATE AUTOMATON APPROACH 
the China-Brazil Earth Resources Satellite (CBERS) work in 
order to retransmit the DCP data back to the ground (INPE, According to theory (Hopcroft & Ullman, 1979), “a finite 
1992). For that communication, the DCP message format is not automaton is a mathematical model of a system, with discrete 
fixed by the satellite and depends only on the compatibility of inputs and outputs. The system can be in any one of a finite 
the DCP message format and the data processor used in the number of internal configurations (or states). The state of the 
Receiving Station. system summarizes the information concerning past inputs that 
is needed to determine the behavior of the system on 
When these satellites pass over the mutual visibility of the DCP subsequent inputs”. 
and the Receiving Ground Station, a communication link is 
established between the DCP and the Receiving Ground After each satellite pass over a Ground Receiving Station, for 
Station, where the received messages are pre-processed, every file received in the Mission Center, the SCMCD 
formatted according to the data processor used there, and acquisition module identifies its origin (the logical channel) 
further transmitted to the Mission Center. In addition, this and, if it is an environmental data message (payload data), the 
Center receives from the Satellite Control Center both the orbit system works on the extraction of all the individual messages 
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B1. Vienna 1996