Digital Signal Processing Reference
In-Depth Information
E5 and E6 bands, supporting 10 different navigation signals offering Open (OS),
Safety-Of-Life (SOL), Commercial and Public Regulated Services. At the time of
publication, the following milestones had been accomplished:
28 December 2005, GIOVE-A, the first GIOVE test satellite, was launched.
27 April 2008, GIOVE-B, with a more advanced payload than GIOVE-A, was
successfully launched.
21 October 2011, the first two of four operational satellites were launched to
validate the system.
12 October 2012, the other two satellites were launched.
1.1.4
Beidou/COMPASS
China is also developing its own GNSS named as Beidou Navigation System (BDS)
by the year 2020 to join the GNSS community of technology and to get the market
share too. The BDS is the name of the future Chinese independent GNSS, formed by
a constellation of 35 satellites, of which five on Geostationary Earth Orbit (GEO)
and 30 on Medium Earth Orbit (MEO). The broadcast signals will be in the E1,
E2, E5 and E6 bands, possibly overlapping with Galileo frequencies. The signals
will be BPSK-modulated (Bi-nary Phase-Shift Keying), and will be broadcast using
CDMA techniques. Similar to Galileo and GPS, different services will be offered: a
standard signal for civilian users and a more precise (encrypted) signal for reserved
uses. A first experimental satellite, named COMPASS M-1, was launched in 2007
and is currently (2011) operational. Its orbit has a low eccentricity, an altitude of
approximately 21.150 km and is 55 inclined. This satellite transmits two signals
(I and Q, in quadrature) in three bands: B1, B2, and B3. This launch was followed
by the orbit placement of three geostationary satellites, one in 2009 and two in 2010.
1.1.5
Other Regional Systems
To compete and augment the existing space-based navigation systems, several
regional systems are being developed by various countries, such as the QZSS by
Japan and the GAGAN/IRNSS by India.
IRNSS
The planned Indian Regional Navigational Satellite System, possibly consisting
of a constellation of seven satellites (of which three geostationary) and a support
ground segment.
QZSS
Quasi-Zenith Satellite System, the Japanese regional system of three satellites
in Highly Elliptical Orbit, that will mainly cover the area between Japan and
Australia. One satellite is in operation at the time of this publication.
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