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51-513: The SVP-24 consists of a GLONASS -supported nav/attack system , a new mission computer, liquid crystal displays , a flight recorder , and a keyboard. It reduces the time needed to program the aircraft's systems before a mission, and it improves the precision of unguided ordnance. It also allows the mission computer to be pre-programmed for automatic weapons release: forward air controllers are able to transmit standardised target coordinates to SVP-24-equipped aircraft. These are automatically fed into

102-412: A 38° cone, using right-hand circular polarization , at an EIRP between 25 and 27 dBW (316 to 500 watts). Note that the 24-satellite constellation is accommodated with only 15 channels by using identical frequency channels to support antipodal (opposite side of planet in orbit) satellite pairs, as these satellites are never both in view of an Earth-based user at the same time. The L2 band signals use

153-629: A full suite of modernized CDMA signals in the existing L1 and L2 bands, which includes L1SC, L1OC, L2SC, and L2OC, as well as the L3OC signal. Glonass-K2 series should gradually replace existing satellites starting from 2023, when Glonass-M launches will cease. Glonass-KM satellites will be launched by 2025. Additional open signals are being studied for these satellites, based on frequencies and formats used by existing GPS, Galileo, and Beidou/COMPASS signals: Such an arrangement will allow easier and cheaper implementation of multi-standard GNSS receivers. With

204-416: A satellite passes over the same location ). GLONASS's orbit makes it especially suited for usage in high latitudes (north or south), where getting a GPS signal can be problematic. The constellation operates in three orbital planes, with eight evenly spaced satellites on each. A fully operational constellation with global coverage consists of 24 satellites, while 18 satellites are necessary for covering

255-472: A solar array span of 7.2 m (24 ft) for an electrical power generation capability of 1600 watts at launch. The aft payload structure houses 12 primary antennas for L-band transmissions. Laser corner-cube reflectors are also carried to aid in precise orbit determination and geodetic research. On-board cesium clocks provide the local clock source. 52 Glonass-M have been produced and launched. A total of 41 second generation satellites were launched through

306-500: A velocity vector measuring within 100 mm/s (3.9 in/s), and timing within 200 nanoseconds , all based on measurements from four first-generation satellites simultaneously; newer satellites such as GLONASS-M improve on this. GLONASS uses a coordinate datum named " PZ-90 " (Earth Parameters 1990 – Parametry Zemli 1990), in which the precise location of the North Pole is given as an average of its position from 1990 to 1995. This

357-481: Is a Russian satellite navigation system operating as part of a radionavigation-satellite service . It provides an alternative to Global Positioning System (GPS) and is the second navigational system in operation with global coverage and of comparable precision. Satellite navigation devices supporting both GPS and GLONASS have more satellites available, meaning positions can be fixed more quickly and accurately, especially in built-up areas where buildings may obscure

408-478: Is composed of 72 frames, each containing 5 strings of 100 bits and taking 10 seconds to transmit, with total length of 36 000 bits or 720 seconds (12 minutes) for the whole navigational message. The additional data are seemingly allocated to critical Lunisolar acceleration parameters and clock correction terms. At peak efficiency, the standard-precision signal offers horizontal positioning accuracy within 5–10 metres, vertical positioning within 15 m (49 ft),

459-666: Is in contrast to the GPS's coordinate datum, WGS 84 , which uses the location of the North Pole in 1984. As of 17 September 2007, the PZ-90 datum has been updated to version PZ-90.02 which differ from WGS 84 by less than 400 mm (16 in) in any given direction. Since 31 December 2013, version PZ-90.11 is being broadcast, which is aligned to the International Terrestrial Reference System and Frame 2008 at epoch 2011.0 at

510-429: Is modulated at 50 bits per second. The superframe of the open signal is 7500 bits long and consists of 5 frames of 30 seconds, taking 150 seconds (2.5 minutes) to transmit the continuous message. Each frame is 1500 bits long and consists of 15 strings of 100 bits (2 seconds for each string), with 85 bits (1.7 seconds) for data and check-sum bits, and 15 bits (0.3 seconds) for time mark. Strings 1-4 provide immediate data for

561-498: Is modulated by an encrypting W code, the GLONASS restricted-use codes are broadcast in the clear using only security through obscurity . The details of the high-precision signal have not been disclosed. The modulation (and therefore the tracking strategy) of the data bits on the L2SF code has recently changed from unmodulated to 250 bit/s burst at random intervals. The L1SF code is modulated by

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612-822: Is sufficient precipitation to form permanent ice , short and still cold summers, and extreme variations in daylight hours, with twenty-four hours of daylight in summer, and complete darkness at mid-winter . There are many settlements in Earth's north polar region. Countries with claims to Arctic regions are: the United States ( Alaska ), Canada ( Yukon , the Northwest Territories and Nunavut ), Denmark ( Greenland ), Norway , Finland , Sweden , Iceland , and Russia . Arctic circumpolar populations, though small, often share more in common with each other than with other populations within their national boundaries. As such,

663-852: Is to be upgraded with the SVP-24. The Russian Navy plans to upgrade the Tu-142 anti-submarine aircraft with the installation of the SVP-24 bombing system. Cooper, Tom (2018). Moscow's Game of Poker: Russian Military Intervention in Syria, 2015-2017 . Warwick, UK: Helion & Company Publishing. ISBN   978-1-912390-37-3 . This Russian military article is a stub . You can help Misplaced Pages by expanding it . GLONASS GLONASS ( ГЛОНАСС , IPA: [ɡɫɐˈnas] ; Russian: Глобальная навигационная спутниковая система , romanized : Global'naya Navigatsionnaya Sputnikovaya Sistema , lit. 'Global Navigation Satellite System')

714-419: Is transmitted with each string; UTC leap second correction is achieved by shortening or lengthening (zero-padding) the final string of the day by one second, with abnormal strings being discarded by the receiver. The strings have a version tag to facilitate forward compatibility : future upgrades to the message format will not break older equipment, which will continue to work by ignoring new data (as long as

765-548: The Russian military intervention in the Syrian civil war , Russian aircraft equipped with the SVP-24 usually missed their targets by around 100 metres. Starting in mid-October 2015, differential correction stations were installed to improve the signal's precision. This improved the average precision of the air strikes to 30–40 metres. A modernization of the Su-24M was introduced in 2000 with

816-624: The frigid zones or polar zones , of Earth are Earth's polar ice caps , the regions of the planet that surround its geographical poles (the North and South Poles ), lying within the polar circles . These high latitudes are dominated by floating sea ice covering much of the Arctic Ocean in the north, and by the Antarctic ice sheet on the continent of Antarctica and the Southern Ocean in

867-623: The "Sukhoi" program and in 1999 with the "Gefest" program. It includes the SVP-24, a new HUD (ILS-31, like in Su-27SM or KAI-24) and expanded armament options ( Kh-31 , Kh-59 MK, KAB-500S ). The last batch of aircraft modernised in accordance to the Sukhoi program was delivered to the VVS in 2009. The modernization continues with the program "Gefest". All Su-24s in the Central Military District received

918-457: The Earth's atmosphere in which it may be absorbed, scattered or reflected, which is the same thing that causes winters to be colder than the rest of the year except in tropical regions. The axial tilt of the Earth has the most effect on climate of the polar regions due to its latitude. However, since the polar regions are the farthest from the equator , they receive the weakest solar radiation and are therefore generally frigid year round due to

969-574: The Ground Control segment; they use Earth Centred Earth Fixed (ECEF) Cartesian coordinates in position and velocity, and include lunisolar acceleration parameters. The almanac uses modified orbital elements (Keplerian elements) and is updated daily. The more accurate high-precision signal is available for authorized users, such as the Russian military, yet unlike the United States P(Y) code, which

1020-483: The L1OF signal. The open standard-precision signal is generated with modulo-2 addition (XOR) of 511 kbit/s pseudo-random ranging code, 50 bit/s navigation message, and an auxiliary 100 Hz meander sequence ( Manchester code ), all generated using a single time/frequency oscillator. The pseudo-random code is generated with a 9-stage shift register operating with a period of 1 milliseconds . The navigational message

1071-540: The SVP-24 in 2013. The Su-25SM3 received the SVP-24 as a result of experience in Syria. In September 2016, it was announced the Su-33 would be outfitted with the SVP-24. The Tu-22M3 is being upgraded with the SVP-24-22 system, and digital processing for the aircraft's radar. A SVP-24-22-equipped Tu-22M underwent trials in 2009, and the program has been ordered into production, with deliveries starting in 2012. The Tu-95MS

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1122-417: The aircraft's nav/attack system, which then generates flight direction commands for the crew to follow. Bombs are then released automatically, without the necessity of acquiring the target with the help of other on-board systems. This system's precision relies entirely on that of the GLONASS signal. As of 2015, the standard-precision GLONASS signal was insufficient for such purposes. Hence, in the first months of

1173-510: The centimetre level, but ideally a conversion to ITRF2008 should be done. Since 2008, new CDMA signals are being researched for use with GLONASS. The interface control documents for GLONASS CDMA signals was published in August 2016. According to GLONASS developers, there will be three open and two restricted CDMA signals. The open signal L3OC is centered at 1202.025 MHz and uses BPSK(10) modulation for both data and pilot channels;

1224-455: The constellation still transmits old string types), but up-to-date equipment will be able to use additional information from newer satellites. The navigational message of the L3OC signal is transmitted at 100 bit/s, with each string of symbols taking 3 seconds (300 bits). A pseudo-frame of 6 strings takes 18 seconds (1800 bits) to transmit. A superframe of 8 pseudo-frames is 14,400 bits long and takes 144 seconds (2 minutes 24 seconds) to transmit

1275-582: The current satellite (string types 10, 11, and 12 in a sequence) and part of the almanac for three satellites (three strings of type 20). To transmit the full almanac for all current 24 satellites, a superframe of 8 pseudo-frames is required. In the future, the superframe will be expanded to 10 pseudo-frames of data to cover full 30 satellites. The message can also contain Earth's rotation parameters, ionosphere models, long-term orbit parameters for GLONASS satellites, and COSPAS-SARSAT messages. The system time marker

1326-540: The earth's axial tilt of 23.5° not being enough to create a high maximum midday declination to sufficiently compensate the Sun's rays for the high latitude even in summer, except for relatively brief periods in peripheral areas near the polar circles. The large amount of ice and snow also reflects and weakens of what weak sunlight the polar regions receive further, contributing to the cold. Polar regions are characterized by extremely cold temperatures, heavy glaciation wherever there

1377-501: The end of 2013. As with the previous generation, the second generation spacecraft were launched three at a time using Proton-K Blok-DM2 or Proton-K Briz-M boosters. Some were launched alone with Soyuz-2-1b / Fregat . In July 2015, ISS Reshetnev announced that it had completed the last GLONASS-M (No. 61) spacecraft and it was putting it in storage waiting for launch, along with eight previously built satellites. As on 22 September 2017, GLONASS-M No.52 satellite went into operation and

1428-727: The full almanac. The navigational message of the L1OC signal is transmitted at 100 bit/s. The string is 250 bits long and takes 2.5 seconds to transmit. A pseudo-frame is 1500 bits (15 seconds) long, and a superframe is 12,000 bits or 120 seconds (2 minutes). L2OC signal does not transmit any navigational message, only the pseudo-range codes: Glonass-M spacecraft produced since 2014 include L3OC signal Glonass-K1 test satellite launched in 2011 introduced L3OC signal. Glonass-M satellites produced since 2014 (s/n 755+) will also transmit L3OC signal for testing purposes. Enhanced Glonass-K1 and Glonass-K2 satellites, to be launched from 2023, will feature

1479-1171: The introduction of CDMA signals, the constellation will be expanded to 30 active satellites by 2025; this may require eventual deprecation of FDMA signals. The new satellites will be deployed into three additional planes, bringing the total to six planes from the current three—aided by System for Differential Correction and Monitoring ( SDCM ), which is a GNSS augmentation system based on a network of ground-based control stations and communication satellites Luch 5A and Luch 5B . Six additional Glonass-V satellites, using Tundra orbit in three orbital planes, will be launched starting in 2025; this regional high-orbit segment will offer increased regional availability and 25% improvement in precision over Eastern Hemisphere , similar to Japanese QZSS system and Beidou-1 . The new satellites will form two ground traces with inclination of 64.8°, eccentricity of 0.072, period of 23.9 hours, and ascending node longitude of 60° and 120°. Glonass-V vehicles are based on Glonass-K platform and will broadcast new CDMA signals only. Previously Molniya orbit , geosynchronous orbit , or inclined orbit were also under consideration for

1530-515: The late 1990s, the restoration of the system was made a government priority, and funding increased substantially. GLONASS is the most expensive program of the Roscosmos , consuming a third of its budget in 2010. By 2010, GLONASS had achieved full coverage of Russia's territory . In October 2011, the full orbital constellation of 24 satellites was restored, enabling full global coverage. The GLONASS satellites' designs have undergone several upgrades, with

1581-410: The latest version, GLONASS-K2 , launched in 2023. GLONASS is a global navigation satellite system, providing real time position and velocity determination for military and civilian users. The satellites are located in middle circular orbit at 19,100 km (11,900 mi) altitude with a 64.8° inclination and an orbital period of 11 hours and 16 minutes (every 17 revolutions, done in 8 sidereal days,

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1632-520: The military "Cosmos-NNNN" designation. The true first generation of GLONASS (also called Uragan) satellites were all three-axis stabilized vehicles, generally weighing 1,250 kg (2,760 lb) and were equipped with a modest propulsion system to permit relocation within the constellation. Over time they were upgraded to Block IIa, IIb, and IIv vehicles, with each block containing evolutionary improvements. Six Block IIa satellites were launched in 1985–1986 with improved time and frequency standards over

1683-536: The most prolific of the first generation. Used exclusively from 1988 to 2000, and continued to be included in launches through 2005, a total of 56 satellites were launched. The design life was three years, however numerous spacecraft exceeded this, with one late model lasting 68 months, nearly double. Block II satellites were typically launched three at a time from the Baikonur Cosmodrome using Proton-K Blok-DM2 or Proton-K Briz-M boosters. The only exception

1734-407: The navigation data at 50 bit/s without a Manchester meander code . The high-precision signal is broadcast in phase quadrature with the standard-precision signal, effectively sharing the same carrier wave, but with a ten-times-higher bandwidth than the open signal. The message format of the high-precision signal remains unpublished, although attempts at reverse-engineering indicate that the superframe

1785-618: The northern polar region is diverse in human settlements and cultures. The southern polar region has no permanent human habitation as of now. McMurdo Station is the largest research station in Antarctica , run by the United States. Other notable stations include Palmer Station and Amundsen–Scott South Pole Station (United States), Esperanza Base and Marambio Base ( Argentina ), Scott Base ( New Zealand ), and Vostok Station (Russia). While there are no indigenous human cultures, there

1836-494: The open signals; this places peak signal strength away from the center frequency of narrow-band open signals. Binary phase-shift keying (BPSK) is used by standard GPS and GLONASS signals. Binary offset carrier (BOC) is the modulation used by Galileo , modernized GPS , and BeiDou-2 . The navigational message of CDMA signals is transmitted as a sequence of text strings. The message has variable size - each pseudo-frame usually includes six strings and contains ephemerides for

1887-455: The orbital grouping has again increased to 24 space vehicles. GLONASS-K is a substantial improvement of the previous generation: it is the first unpressurised GLONASS satellite with a much reduced mass of 750 kg (1,650 lb) versus the 1,450 kg (3,200 lb) of GLONASS-M. It has an operational lifetime of 10 years, compared to the 7-year lifetime of the second generation GLONASS-M. It will transmit more navigation signals to improve

1938-409: The other two climatic and biometric belts of Earth, a tropics belt near the equator, and two middle latitude regions located between the tropics and polar regions . Polar regions receive less intense solar radiation than the other parts of Earth because the Sun's energy arrives at an oblique angle , spreading over a larger area, being less concentrated, and also travels a longer distance through

1989-402: The prototypes, and increased frequency stability. These spacecraft also demonstrated a 16-month average operational lifetime. Block IIb spacecraft, with a two-year design lifetimes, appeared in 1987, of which a total of 12 were launched, but half were lost in launch vehicle accidents. The six spacecraft that made it to orbit worked well, operating for an average of nearly 22 months. Block IIv was

2040-735: The ranging code transmits at 10.23 million chips per second, modulated onto the carrier frequency using QPSK with in-phase data and quadrature pilot. The data is error-coded with 5-bit Barker code and the pilot with 10-bit Neuman-Hoffman code. Open L1OC and restricted L1SC signals are centered at 1600.995 MHz, and open L2OC and restricted L2SC signals are centered at 1248.06 MHz, overlapping with GLONASS FDMA signals. Open signals L1OC and L2OC use time-division multiplexing to transmit pilot and data signals, with BPSK(1) modulation for data and BOC(1,1) modulation for pilot; wide-band restricted signals L1SC and L2SC use BOC (5, 2.5) modulation for both data and pilot, transmitted in quadrature phase to

2091-580: The regional segment. The main contractor of the GLONASS program is Joint Stock Company Information Satellite Systems Reshetnev (ISS Reshetnev, formerly called NPO-PM). The company, located in Zheleznogorsk , is the designer of all GLONASS satellites, in cooperation with the Institute for Space Device Engineering ( ru:РНИИ КП ) and the Russian Institute of Radio Navigation and Time. Serial production of

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2142-502: The same FDMA as the L1 band signals, but transmit straddling 1246 MHz with the center frequency 1246 MHz + n × 0.4375 MHz, where n spans the same range as for L1. In the original GLONASS design, only obfuscated high-precision signal was broadcast in the L2 band, but starting with GLONASS-M, an additional civil reference signal L2OF is broadcast with an identical standard-precision code to

2193-421: The same code as their standard-precision signal; however each transmits on a different frequency using a 15-channel frequency-division multiple access (FDMA) technique spanning either side from 1602.0 MHz , known as the L1 band. The center frequency is 1602 MHz + n × 0.5625 MHz, where n is a satellite's frequency channel number ( n =−6,...,0,...,6, previously n =0,...,13). Signals are transmitted in

2244-449: The satellites is accomplished by the company Production Corporation Polyot in Omsk . Over the three decades of development, the satellite designs have gone through numerous improvements, and can be divided into three generations: the original GLONASS (since 1982), GLONASS-M (since 2003) and GLONASS-K (since 2011). Each GLONASS satellite has a GRAU designation 11F654, and each of them also has

2295-517: The south. The Arctic has various definitions, including the region north of the Arctic Circle (currently Epoch 2010 at 66°33'44" N), or just the region north of 60° north latitude, or the region from the North Pole south to the timberline . The Antarctic is usually defined simply as south of 60° south latitude, or the continent of Antarctica. The 1959 Antarctic Treaty uses the former definition. The two polar regions are distinguished from

2346-621: The system's accuracy — including new CDMA signals in the L3 and L5 bands, which will use modulation similar to modernized GPS, Galileo, and BeiDou. Glonass-K consist of 26 satellites having satellite index 65-98 and widely used in Russian Military space. The new satellite's advanced equipment—made solely from Russian components — will allow the doubling of GLONASS' accuracy. As with the previous satellites, these are 3-axis stabilized, nadir pointing with dual solar arrays. The first GLONASS-K satellite

2397-400: The territory of Russia. To get a position fix the receiver must be in the range of at least four satellites. GLONASS satellites transmit two types of signals: open standard-precision signal L1OF/L2OF, and obfuscated high-precision signal L1SF/L2SF. The signals use similar DSSS encoding and binary phase-shift keying (BPSK) modulation as in GPS signals. All GLONASS satellites transmit

2448-399: The transmitting satellite, and are repeated every frame; the data include ephemeris , clock and frequency offsets, and satellite status. Strings 5-15 provide non-immediate data (i.e. almanac ) for each satellite in the constellation, with frames I-IV each describing five satellites, and frame V describing remaining four satellites. The ephemerides are updated every 30 minutes using data from

2499-476: The view to some satellites. Owing to its higher orbital inclination , GLONASS supplementation of GPS systems also improves positioning in high latitudes (near the poles). Development of GLONASS began in the Soviet Union in 1976. Beginning on 12 October 1982, numerous rocket launches added satellites to the system until the completion of the constellation in 1995. In 2001, after a decline in capacity during

2550-700: Was successfully launched on 26 February 2011. Due to their weight reduction, GLONASS-K spacecraft can be launched in pairs from the Plesetsk Cosmodrome launch site using the substantially lower cost Soyuz-2.1b boosters or in six-at-once from the Baikonur Cosmodrome using Proton-K Briz-M launch vehicles. The ground control segment of GLONASS is almost entirely located within former Soviet Union territory, except for several in Brazil and one in Nicaragua. High latitude The polar regions , also called

2601-473: Was when, on two launches, an Etalon geodetic reflector satellite was substituted for a GLONASS satellite. The second generation of satellites, known as Glonass-M , were developed beginning in 1990 and first launched in 2003. These satellites possess a substantially increased lifetime of seven years and weigh slightly more at 1,480 kg (3,260 lb). They are approximately 2.4 m (7 ft 10 in) in diameter and 3.7 m (12 ft) high, with

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