258
14 Pseudo-Ranging Radio Navigation Systems
The global navigation satellite system GALILEO is built up by the European
Union to ensure the independence of the member states in the field of coordinate
time and navigation support. The European GNSS Program was officially approved
in 1994, when the European Council asked the European Commission to take steps
to develop information technology, including satellite navigation. It was decided to
develop two directions. The first of them is systems of functional supplement to
existing GPS and GLONASS. This program is called the European Geostationary
Navigation Overlay Service (EGNOS). The second direction was to build its own
SRNS, intended for civilian use and built on the principles of public–private partnership. In 1999, the European GNSS project was codenamed GALILEO in honor of the
Italian astronomer Galileo Galilei. Experimental satellites GIOVE-A and GIOVE-B
were launched into orbit on December 28, 2005 and April 27, 2008, respectively. The
main task of GIOVE-A was to assess the accuracy characteristics of the GALILEO
navigation radio signals in all frequency bands, and GIOVE-B—to test the navigation
payload.
The first two NSVs were launched on October 20, 2011, using a Soyuz-STB rocket
from the Kourou launch site. The launch technology of the GALILEO satellites
assumes group launches of two satellites on the Russian Soyuz carrier rocket and
four satellites each on the European Ariane-5 missile.
The fully deployed GALILEO orbital constellation will provide three modes of
navigation service and provide the following types of navigation services:
• Open Service—open signals, without subscription and other fees, available to all
types of users;
• Commercial Service—encrypted signal, access to two additional signals, higher
data transfer rate. The commercial service will provide two functions—global
high-precision navigation and navigation signal authentication. For the technical
implementation of the commercial service CS signals of an open service plus two
encrypted signals in the E6 band (GALILEO signals) will be used;
• service with regulated access by the state (Public Regulated Service)—for the
coordinate time provision of regulated users (two PRS signals with encrypted
rangefinder codes).
The orbital architecture of GALILEO assumes that there will be 27 NSVs in orbit
in three circular orbits with an altitude of 23,229 km, an orbital period of 14 h, and
an inclination of 56˚. A total of 24 satellites are used for its intended purpose, one
satellite in each orbital plane is a backup one. Such a constellation configuration
was chosen based on the guaranteed fulfillment of requirements in accuracy and
accessibility at the minimum expenditures on orbit correction during the lifetime of
the space vehicle.
The characteristics of the orbital GALILEO grouping are given in Table 14.7.
Table 14.8 shows the NSV technical characteristics of the GALILEO system.
The spectrum of the navigation radio signals of the GALILEO system is shown
in Fig. 14.9. The characteristics of the navigation radio signals of the GALILEO
system are given in Table 14.9 (Fig. 14.8).
14 Pseudo-Ranging Radio Navigation Systems
The global navigation satellite system GALILEO is built up by the European
Union to ensure the independence of the member states in the field of coordinate
time and navigation support. The European GNSS Program was officially approved
in 1994, when the European Council asked the European Commission to take steps
to develop information technology, including satellite navigation. It was decided to
develop two directions. The first of them is systems of functional supplement to
existing GPS and GLONASS. This program is called the European Geostationary
Navigation Overlay Service (EGNOS). The second direction was to build its own
SRNS, intended for civilian use and built on the principles of public–private partnership. In 1999, the European GNSS project was codenamed GALILEO in honor of the
Italian astronomer Galileo Galilei. Experimental satellites GIOVE-A and GIOVE-B
were launched into orbit on December 28, 2005 and April 27, 2008, respectively. The
main task of GIOVE-A was to assess the accuracy characteristics of the GALILEO
navigation radio signals in all frequency bands, and GIOVE-B—to test the navigation
payload.
The first two NSVs were launched on October 20, 2011, using a Soyuz-STB rocket
from the Kourou launch site. The launch technology of the GALILEO satellites
assumes group launches of two satellites on the Russian Soyuz carrier rocket and
four satellites each on the European Ariane-5 missile.
The fully deployed GALILEO orbital constellation will provide three modes of
navigation service and provide the following types of navigation services:
• Open Service—open signals, without subscription and other fees, available to all
types of users;
• Commercial Service—encrypted signal, access to two additional signals, higher
data transfer rate. The commercial service will provide two functions—global
high-precision navigation and navigation signal authentication. For the technical
implementation of the commercial service CS signals of an open service plus two
encrypted signals in the E6 band (GALILEO signals) will be used;
• service with regulated access by the state (Public Regulated Service)—for the
coordinate time provision of regulated users (two PRS signals with encrypted
rangefinder codes).
The orbital architecture of GALILEO assumes that there will be 27 NSVs in orbit
in three circular orbits with an altitude of 23,229 km, an orbital period of 14 h, and
an inclination of 56˚. A total of 24 satellites are used for its intended purpose, one
satellite in each orbital plane is a backup one. Such a constellation configuration
was chosen based on the guaranteed fulfillment of requirements in accuracy and
accessibility at the minimum expenditures on orbit correction during the lifetime of
the space vehicle.
The characteristics of the orbital GALILEO grouping are given in Table 14.7.
Table 14.8 shows the NSV technical characteristics of the GALILEO system.
The spectrum of the navigation radio signals of the GALILEO system is shown
in Fig. 14.9. The characteristics of the navigation radio signals of the GALILEO
system are given in Table 14.9 (Fig. 14.8).