Geoscience Reference
In-Depth Information
positioning data for users through data processing. Then, the data files formed with
a certain format are distributed to users. The data processing center is the essential
part of CORS as well as the key to realizing high-precision real-time dynamic
positioning. After a continuous around-the-clock solution of the whole modeling
within an area based on real-time observational data collected by every datum
station, the center automatically generates a virtual reference station (including the
coordinates of datum stations and GPS observations) corresponding to the mobile
station and provides various users who are in need of measurement and navigation
with code phase/carrier phase differential correction information in a universal
common format via the existing data communication networks and wireless data
broadcast systems so as to calculate the exact real-time position of mobile stations.
The data transmission system, where data from every datum station are trans-
mitted to the monitoring and analysis center through fiber lines. The system
comprises hardware devices for data transmission and software control module.
The data broadcast system broadcasts positioning and navigation data to users in
the form of mobile networks, UHF radio, Internet, etc.
The user application system consists of a user information receiving system, a
network-based RTK (real-time, kinematic) positioning system, a fast and post-
processing precision positioning system, an autonomous navigation system, posi-
tioning monitoring system, and so on. According to different application accura-
cies, the user service subsystem ranges from millimeter-level, centimeter-level,
decimeter-level, to meter-level whereas, according to different user applications, it
can be categorized into surveying and mapping and engineering users (centimeter-
and decimeter-level), vehicle navigation and positioning users (meter-level), high-
precision users (post-processing), and meteorology users.
CORS is not only a kinematic and continuous positioning reference frame but
also an important technical means for rapid and high-precision acquisition of spatial
data and geographic features. CORS is more often applied in small areas, for
instance, a city, to provide three-dimensional datum. Within an area, it provides
highly precise, reliable, and real-time positioning information to a large number of
users simultaneously and unifies the surveying and mapping data in the city. For
example, the application of CORS in cities will exert a profound and lasting
influence on the collection of modern urban geographic information and the
application system. Not only can it establish and maintain a reference frame of
the surveying and mapping in cities, it can also provide automatically all-weather
real-time spatial and temporal information of high-precision, serving as the basis of
regional planning, management, and decision-making. It can also provide differ-
ential positioning information and develop new applications of transportation
navigation; again it enables high-precision, high-spatial-and-temporal-resolution,
all-weather, near-real-time, and continuous variable sequences in precipitable water
vapor, which will gradually form a regional severe weather monitoring and fore-
casting system. CORS can also be used in the high-precision time synchronization
in communication and power systems and will provide the services of monitoring
and predicting land subsidence, geological disasters, and earthquakes and will study
the temporal and spatial evolution of natural disasters.
Search WWH ::
Custom Search