Global Positioning System Reference
In-Depth Information
In an apparent competing initiative to BeiDou-2, the Chinese also joined the
GALILEO program in late 2003. However, it is clear from the Chinese perspective
that cooperation with the GALILEO program will not replace or hinder plans for
the Chinese to deploy their own indigenous system; these efforts are complemen-
tary, not competitive, options.
As part of the development of the BeiDou-2 program, the Chinese have filed for
radio frequency allocation by the ITU Radio Board under the “Chinasat” and
“Compass” designations. At the time of this writing, the Chinese had filed for a total
of 61 satellites, apparently in an effort to secure orbital slots and radio frequency
allocations for potential design options for BeiDou-2. Based on the information con-
tained in the request to the ITU and the Chinese press, there are apparently four
design options under consideration. These are outlined in Table 11.6 [61-64].
In 1997, the Chinese filed for a follow-on to BeiDou-1 under the Chinasat-34
and Chinasat-35 designators. The ITU filing indicated that they planned a constella-
tion of satellites similar to BeiDou-1c (Chinasat-33) supporting both an RDSS and
SBAS capabilities. However, in this case, they planned to place two or three satellites
in the two orbital slots currently occupied by BeiDou-1a (140ºE longitude) and
BeiDou-1b (80ºE longitude). No satellites were planned to fill the middle orbital
slot, currently occupied by BeiDou-1c (110ºE longitude). Although the Chinese have
Table 11.6
Chinese Design Options for BeiDou-2
Design Option 1
Design Option 2
Design Option 3
Design Option 4
Chinasat-34a and b
and Chinasat-35a, b,
and c
Compass-GEOs and
Compass-highly
elliptical orbit (HEO)
Compass-GEOs and
Compass-medium Earth
orbit (MEO)
Compass-MG
ITU
designators
ITU filing
date
1997 with continued
coordination in Dec.
2003
2000 and amended
in Nov. 2003
2000 and amended in
Nov. 2003
Registered in 2003
Constellation
design
2 GEO
+
2-3 GEO
4 GEO
9 inclined
geosynchronous
+
4 GEO
+
12 MEO
30 MEO
55ºE, 80ºE, 110ºE,
140ºE, and 160ºE
longitude
55ºE, 80ºE, 110ºE,
140ºE, and 160ºE
longitude
Orbit
80ºE and 140ºE
longitude
3 orbital planes at
56º inclination
×
21,363-km circular
orbits
6 orbital planes at 55º
inclination
6 orbital planes at
50º inclination
20,200-km
circular orbits
×
×
36,000-km circular
orbits
Two-dimensional
RDSS
GPS augmentation
Two-dimensional
active RDSS
GPS augmentation
Three-dimensional
passive navigation
Two-dimensional
active RDSS
GPS augmentation
Three-dimensional
passive navigation
Three-dimensional
active RDSS
Navigation
techniques
Three-dimensional
passive navigation
S-band and L-band
communication links
Two L-band naviga-
tion links
S-band and L-band
communication links
Four L-band
navigation links
S-band and L-band
communication links
Four L-band navigation
links
S-band and L-band
communication
links
Four L-band
navigation links
Planned radio
frequencies
Service area
Asian-Pacific region
Asian-Pacific region
Asian-Pacific region
Worldwide
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