GLONASS

GLONASS (Russian: ГЛОНАСС, IPA: [ɡlɐˈnas]; Глобальная навигационная спутниковая система; transliteration Globalnaya navigatsionnaya sputnikovaya sistema), or "GLObal NAvigation Satellite System", is a space-based satellite navigation system operating in the radionavigation-satellite service and used by the Russian Aerospace Defence Forces. It provides an alternative to GPS and is the second alternative navigational system in operation with global coverage and of comparable precision.

Manufacturers of GPS devices say that adding GLONASS made more satellites available to them, meaning positions can be fixed more quickly and accurately, especially in built-up areas where the view to some GPS satellites is obscured by buildings. Smartphones generally tend to use the same chipsets and since the versions used since 2015 receive GLONASS signals, smartphones using such chips receive GLONASS positioning information along with GPS. Since 2012, GLONASS was the second most used positioning system in mobile phones after GPS. The system has the advantage that smartphone users receive a more accurate reception of up to 2 meters.

GLONASS-M

GLONASS-M (Russian: ГЛОНАСС-М), also known as Uragan-M (Russian: Ураган-М) (GRAU Index 11F654M and manufacturing code 14F113) are the second generation of Uragan satellite design used as part of the Russian GLONASS radio-based satellite navigation system. Developed by Reshetnev Information Satellite Systems, it had its debut launch in 2003, and is in the process of being phased out. Its production is expected to finish in 2015 and as of July, 2015, its last launch is expected in late 2017. It is an evolution of the previous Uragan (GRAU Index 11F654) second-generation satellites, improving accuracy, increasing power, extending the design life and adding the FDMA L2OF open signal.

Design

It used a 3-axis stabilized pressurized bus with two solar panels, a propulsion module and a payload module. At 1,415 kg (3,120 lb) these are just 2 kg (4.4 lb) heavier than the previous generation, but have 25% more power 1250 W, 230% more design life (7 years), an additional signal (L2OF) and generally improved accuracy. It uses an on-board computer based on a Russian microprocessor using the VAX 11/750 instruction set (the Angstrem K1839 (Russian Wikipedia)).

GLONASS (satellite)

GLONASS (Russian: ГЛОНАСС-М), also known as Uragan (Russian: Ураган) (GRAU Index 11F654) are the first generation of Uragan satellite used as part of the Russian GLONASS radio-based satellite navigation system. Developed by Reshetnev Information Satellite Systems, it had its debut launch in 1983, with the last launched unit on 2005 and the retirement of the last unit Kosmos 2403 on April 30, 2009. I has been superseded by the GLONASS-M (GRAU Index 11F654M), the second-generation satellites.

Design

It used a 3-axis stabilized pressurized bus with two solar panels, a propulsion module and a payload module. It weights 1,413 kg (3,115 lb) generates 1000W of power and had a limited design life of 3 years, but it was extended to 5 years in later models. It had a strict requirement of keeping the internal temperature at ±1°C. The previous design used an embedded liquid cooling system that weighted 340 kg (750 lb). The Uragan implemented a gaseous cooling system that put most of the heat generating parts on the outside of the pressure vessel, simplifying the system and weighting just 40 kg (88 lb).