GLONASS SYSTEM
GLONASS (Global Navigation Satellite System) is a global position Satellite System realized by ex-Urss at the same time with the United State's one.All satellites are launch from Baikonur Cosmodrome in Kazakhstan.The first launch of satellites went back to 12th October 1982, they completed constellation in period of maxime efficiecy with 24 satellites in 1997.
In the years succeeded because of the serious economic situation interns Russia has not had the possibility to maintain to assets the entire constellation.
But in 2002 with improving of the economic situation it has been given the way to the program of I throw again of the system to satellitare Glonass that previews 18 satellites within 2007, and will have to newly catch up the number of 24 satellites within 2010.
The program previews at least a launch for year, everyone of which will carry in the space two or three satellites.
In the constellation now:
Satellites type GLONASS
Satellites type GLONASS-M
Glonass
Type application:Navigation
Configuration:3-Axis stabilized, 2 solar arrays
LifeTime:3 years Mass
Mass:1415 kg
Orbit & inclination:19100 km, 64.8°
Glonass - M
Type application:Navigation
Configuration:3-Axis stabilized, 2 solar arrays
LifeTime:7 years Mass
Mass:1415 kg
Orbit & inclination:19100 km, 64.8°
From the 2010 they will be puttinges in orbit satellites of new generation GLONASS-K
Glonass - K
Type application:Navigation
Configuration:3-Axis stabilized, 2 solar arrays
LifeTime:10 ~ 12 years
Mass:750 Kg
Orbit & inclination:19100 km, 64.8°
GLONASS constellation is managed by System Control Center (SCC)
TT&C:Telemetry, Tracking and Control
ULS:Uplink station
MS:Monitoring station
CC:Central clock
SLR:Laser tracking station
GPS and GLONASS are very similar systems, but some differences are significant:
In the first place the GLONASS does not have no degradation of the precision neither cryptography
Orbits of the 2 types of satellite are similar:
- Satellites GLONASS rotate on 3 orbital planes separated by an angle of 120°
8 satellites for each plane and are equally spaced from an angle of 45°and identified by slot number which defines the corresponding orbital plane and the location within the plane (ex.1/01 - 1/02 - 3/23) - Satellites GPS rotate on 6 planes, 4 for each plane.
- 64.8° on the GLONASS and 55° in the GPS.
- Altitude is :
19.140 Km (GLONASS) and period of revolution is 11h 15m
20.180 Km (GPS) and period of revolution is 11h 58m.
Advantage that derives the use co-ordinated of both constellations characterized from the fact that if they are observed more satellites contemporarily obtain more accurate precisions and saving in the times of acquisition.
| Glonass | Glonass-M | Glonass-K | |
|---|---|---|---|
| First launch | 1982 | 2003 | 2010 |
| Lifetime (years) | 3 | 7 | 10-12 |
| Mass (Kg) | 1415 | 1415 | 750 |
| Output power (W) | 1000 | 1600 | 1270 (TBC) |
| Nr di Satellites per launch:
- Proton - Soyuz |
3
- |
3
1 |
6
2 |
| Vertical real time navigation accuracy(95%) | 60 m | 30 m | 5-8 m (TBC) |
| Number of civil signals | 1 | 2 | 3 (TBC) |
| Number of special signals | 2 | 2 | 3 (TBC) |
| On board clocks stability | 5x10-13 | 1x10-13 | 1x10-13 |
| Root-mean-square error of mutual synchronization of navigation signals | 15 ns | 8 ns | 3-4 ns |
TBC – To be Confirmed
TBD – To be defined
| GLONASS | G.P.S. | |
| Number of satellites | 24 | 30 |
|---|---|---|
| Number of orbital planes | 3 | 6 |
| Orbital Inclination | 64°8' | 55° |
| Orbital altitude | 19.140 Km | 20.180 Km |
| Period of revolution | 11h 15m | 11h 58m |
| Launch site | Baikonur | Cape Canaveral |
| Vehicle | Proton K/Dm2 | Delta II |
| Date of first launch | 02/10/82 | 22/02/78 |
| Satellites for launch | 3 | 1 |
| Carrier Frequency (Mhz) | 25 chanel separated by:0.5625 MHz |
Bandwith 20 Mhz |
| L1 L2 |
1602.5625 - 1615.5 1240 - 1260 |
1575.42 1227,60 |
| Clock Precision |
Cesium 5*10-13 |
Cesium & Rubidium 1 sec/300.000 years |
| Datum | PZ-90.02 | WGS-84 |