Report On Military Applications Of Gnss Information Technology Essay

Report On Military Applications Of Gnss Information Technology EssayRecent years have witnessed an increasingly hire of GNSS technologies in diverse beas of human endeavours. Governments, organisations, individuals etc. are beginning to rely upon GNSS technology in finding firmnesss to problems in different fields of life (Spirent, 2002 17). atomic number 53 obvious area where GNSS technology has been deployed successfully since the launching of satellite sailing is in forces applications. Military applications of GNSS date back in 1978 when the first human beings-wide posture System was launched by US Department of Defence. Since then, many GNSS and associated sailing dodgings are being used in army machine mission fields. This report examines ult and present military applications of GNSS it also attempts to look into future of military applications in the context of emerging trends and developments in GNSS world.1.2 Global navigation Satellite Systems (GNSS)Global Na vigation Satellite Systems (GNSS) is generic term encompassing all satellite navigation systems that allows users to determine their locations by observing radio betokens transmitted by GNSS satellites. First among them is the US Navigation by Satellite Ranging and Timing (NAVSTAR) Global Positioning System (GPS). Russian Global Navigation Satellites System (GLONASS) is the second generation of GNSS, conceived also as a military system.. The next generation of GNSS is the European Unions Galileo which is expected to be in full public presentation by early 2014. GNSS market is poised for whirling with the full deployment of Galileo constellation of satellites. Other Regional GNSS include Beidou operated by China, although through its Compass, China has planned to launch satellite navigation system with global reportage. Indian Regional Navigation Satellite System (IRNSS) is another GNSS in the development. Uncertainty still trail IRNSS project since India entered into partnership with Russian GLONASS. QZSS is another regional navigation system operated by Japan. It is developed to supplement GPS sign ups in Japan and neighbouring areas.Besides these, there are other regional GNSS space- base augmentation systems aim to improve the performance of GPS/GLONASS. The major regional augmentation systems are WAAS, EGNOS (European Geostationary National Overlay Service), MTSAT-Based Satellite Augmentation System (MSAS) in Japan and Indian GPS Aided Geo Augmented Navigation (GAGAN)GPS and GLONASS stand divulge among the list when it comes to military applications. GPS and GLONASS have been used in many military operations.1.3 Global Positioning Systems (GPS)US Global Positioning System (GPS) was designed as a dual-use technology (civilian and military use). The military position service available to civil users is called Standard Positioning Service, while that of the military is called Precise Positioning Service. GPSs Precise Positioning Service (PPS) is used for most military applications. Precise Positioning Service is restricted to only US military, NATO forces, and other users licensed by US Government. The encrypted detailed code signals P(Y) and M-code are used for military applications. M- Code is a new signal being to realise the fundamental aim of achieving precise and accurate navigation services for military applications. These signals are broadcasted in link 1 (L1) and link 2 (L2) bands. L1C-d and L1C-p signals impart be added to the PPS users under the GPS phased modernisation course of instruction (Groves, 2008 12). In measure of navigation data messages, MNAV message broadcasts are broadcast on M-code signals. GPS is presently undergoing phased restructuring and modernisation and it is expected that new programme will ensure that existing users are transmitted P(Y) code while the new users are transmitted new M code (Kaplan and Hegarty (2006 654).1.4. GLONASSLike GPS, GLONASS was conceived as a military system still designed to offer both military and civil positioning service (Groves 2008 17). GLONASS P code signals are used for military applications and transmitted in both bands LI and L2 with frequencies 1592.95MHz 1613.86MHz and 1237.83 MHz 1256MHz respectively (Groves, 2008 19). GLONASS K, fully modernised satellites are set to broadcast new signals that will improve the truth of military operations.2.0 GNSS Positioning RequirementsThe positioning principles are basically the same for GNSS systems. Generally, a GNSS receiver records three or more satellites signals to determine a 2 dimensional coordinates, while four or more signals are needed for 3 dimensional coordinates. The accuracy of GNSS position root word depends on the type of GNSS device used and application under consideration. verityAccuracy is a critical factor in military applications. GPS was launched because of the military requirements for high up accurate global navigation (Len, 2007185). In case of timing service , military operations require precise m transfer for synchronization of equipment and several(a) operations (Len 2007 184). The GPS PPS offers plane accuracy of 1.2m and vertical accuracy of 1.9m based on 24 satellite constellations (Groves, 2008). With its modernisation program, GLONASS is set to compete with GPS as it planned to achieve the same positioning accuracy with GPS. The Galileo Public-Regulated Service (PRS) has a lower accuracy when compared to that of GPS PPS it has horizontal accuracy of 3m and vertical accuracy of 6m, much more lower to its Open Service (Groves, 2008 20)AvailabilityAvailability is also of the important characteristics of GNSS performance. Availability of navigation system is defined by US Federal Radionavigation Plan (FRP) as the percentage of time that the services of the system are within the required performance limits (Wang et al 2006 1). Global availability of GNSS for military applications is expected to increase with the ongoing modernisat ion of GLONASS. GLONASS K satellites when fully launched will improve the accuracy of P code for military applications. India has partnered with Russia in the GLONASS project, and it is expected that India and other countries will have access GLONASS military signals for their mission operations and equipment testing. Aside from GPS military signals, more countries are today use civil signals in many military missions and equipment testing.IntegrityGPS will have full integrity monitoring and alert system as the fourth component when the modernisation programme is completed. GLONASS K satellites will broadcast integrity information and derivative corrections in L3 band. Similarly, Galileo will broadcast integrity alerts and some differential corrections.2.1 GNSS MarketsGNSS technology is naturally divided into two broad markets/applications civil / commercial markets and military markets. The user equipment used in military applications can be classified into two types(i) GNSS receivers operated by human beings such as handheld type, human operated receivers on ships, aircrafts and vehicles (Len, 2007 184 -185)(ii) Autonomous receivers these are not dependent of any human operation and usually integrated with inertial sensors. They are used in guided missile programs and newer military applications.Comparison between Military and civil ReceiversMilitaryCivilFrequenciesL1, L2L1 and /or L1, L2 (L5 on 11F satellitesCodesP(Y), M, C/A, CC/A and C (on modernised satellitesSize/weight/powerCard, handheld, receiver social unitChips, handheld, receiver unitNavigation accuracy1m to 5m5m to 10mAnti interferenceGreater than 54 dBUsually not more than 24 dBIntegrationA/J antennas, communications, inertial sensorsSpeed/heading sensors, communications, GIS, inertial sensorsAdapted from (Len 2007 183)3.0 Military Applications of GNSSOf all GNSS, GPS has been most widely used in military applications. Essentially, GPS was developed to satisfy military requirements fo r a global positioning, navigation and timing service. (Kaplan, and Hegarty, 2006 654). Military application of GPS started in late 1970s when GPS was used for weapon testing in the then US Navy Submarine Launched Ballistic Program (SLBM). GPS was used to track the Submarine Launched Ballistic Missiles from a ship as the missile travelled down the Atlantic (Len, 2007 174). The GPS military equipment used for the missile testing then made use of translator. Subsequently, other weapon testing was conducted in the air and ground vehicles (Len, 2007 177). Today, GPS can be deployed to variety of military applications. Some of these include target acquisition missile guidance, search and rescue coordinate bombing precision survey, instrument approach antisubmarine fightfare range instrumentation remotely piloted vehicle operations barebase operations close air support en route navigation command and fudge field artillery and shore bombardment rendezvous, sensor emplacement etc. (Len, 2007 177 -178). Other military applications of GNSS include mine location, enemy radar location, Special Forces acquaintance gathering etc (Dye and Baylin, 1997 82).3.1 GNSS/ Inertial Integration SystemsGNSS such as GPS has been proved to be weak in term of providing high quality and reliable position solution (Spirent, 2010). Thus inertial sensors are being used in many applications to complement GNSS. Inertial navigation system is a small, self contained device that uses inertial sensors (accelerometers and gyroscopes) to calculate position and velocity solution of a moving object (Logsdon, 1995 39). It makes use of dead reckoning navigation system (Groves 2008 7). Using GPS measurements, INS navigation solution is calibrated and corrected via integration algorithm (Groves and Long, 2005 2). GPS/INS integration is popular in the guided weapons and unmanned air vehicles (UAVs) where low cost sensors are used (Groves and Long, 2005 2). INS amour independently of GNSS signals susc eptible to jamming, interference, enemy manipulation and other distortions and are therefore used in many military applications (Dye and Baylin, 1997 13). Examples of practical applications of GNSS/INS based solutions are stipulation in the report.Advantages of GNSS/INS based solutionINS offers continuous navigation operations it provides high-bandwidth output (50 Hz) and low short-term noise it also provides attitude, angular rate, and acceleration measurements as sound as position and velocity (Groves and Long 2005 419) (Groves 2008 8). GPS provides a high accuracy which does not drift with time(Groves and Long, 2005 419)Disadvantages of GNSS/INS based solution The accuracy of INS output is degraded with time thus necessitating the need to calibrate the errors (Groves 2008 8). Unlike INS, GNSS has lower bandwidth (1Hz), more noisier than that INS and does not usually include altitude (Groves and Long 2005 419, 420)One obvious challenge in the military use of GNSS is issue of del iberate jamming and interference by the enemies. GPS receivers have been found to be susceptible to jamming due to low signal power of GPS signal. This trend has raised a concern to US Department of Defence in the recent years thus signalling the programme of developing various anti-jamming techniques to mitigate these effects. Recent anti jamming technologies include nulling of antennas and ultra tight coupling of the GPS and the inertial sensors (Kaplan, and Hegarty (2006 656).3.2 Practical Applications of GPS in Precision GuidanceIn 1991, US army and its allies successfully deployed GPS in the attack to rescue oil rich Kuwait after its invasion by Iraq in an operation tagged Operation Desert Storm. GPS receivers were fitted in the military aircrafts and helicopters, bombs were dropped from these aircrafts as targeted thus eliminating unwanted casualties. GPS receivers were used to know the coordinates of the targets so that the weapons can be delivered accurately.In 1995, GPS w as also deployed during the Bosnia war by the combined US and NATO forces in a campaign tagged Operation Deliberate Force. Military aircrafts operating from their base in Italy were fully fitted out(p) with GPS equipment in the strike against the Bosnia Serb forces.Perhaps, the Joint Direct Attack Munition (JDAM) is the most impressive breakthrough GPS has achieved in area of precision guidance. JDAM is an independent, tail kit with gloominess bomb it is usually mounted on the military fighter jets and uses GPS/INS guidance to deliver the target (Cozzens, 2006). JDAM has the capability of working in all weather conditions and its accuracy is not dependent on the altitude (Cozzens, 2006). JDAM recorded 9.6m accuracy during their testing. JDAM have been successfully deployed in many operations. For example, in June 2006, US Air Force successfully used GBU-38 Joint Direct Attack Munition equipped with GPS precision guidance to kill former Iraq terrorist leader Abu Musab al Zarqawi in his house (Cozzens, 2006). formerly on the air, GPS/INS guidance enables the gravity bomb to be delivered accurately at the targets (Cozzens, 2006).In case of GLONASS, Russian military has deployed GLONASS military signals in many missions (Len, 2007 189). Russian Federation Airforce recently developed latest KAB family of weapons called KAB 500S. KAB 500S is a guided bomb similar to that of US JDAM. KAB 500S can be dropped from aircraft at altitudes of 500 to 10,000 metres and airspeeds of 550 to 1,100 kilometres per arcminute (Deagel, 2007). It uses GLONASS Military code and INS to strike the targets (Len, 2007 189). The third generation GNSS, Galileo has encrypted signal Public Regulated Service that may be used for military applications in the boney future.4.0 GNSS Future and Military ApplicationsThe GNSS have made giant strides in military applications particularly in area of guided weaponry and cleverness bombs. GPS-aided munitions, ranging from artillery shells to smart shells have proved to be a reliable technology in recent time in times of accuracy (Lucio, (2002), (Wells, (2001). Countries all over the world will continue to embrace these technologies as cheaper GPS/INS coupled munitions are being produced to meet the requirements for accurate, precise timing and navigation solutions in the land, air and sea in near future.Current developments in GNSS industry like new signals and constellations acquisition will usher new era of high accurate military based satellite navigation. The separation of GPS signals for military and civilian use will lessen the effects of jamming and interference in military operations coupled with high signal power of new M code. GPS new military code will improve the anti-jamming capability of the system as current modernisation programme will make it autonomous. Non coherence integration of the acquisition circuit of the new military code will enhance the performance of the system in the strawman of noise and jamming (Betz et al, 2005 45, 46). In the area of system integrity, modernization programme of GPS and GLONASS will offer users more reliable measurements as they will have options to support GNSS measurements.Presently, only GPS and GLONASS are used for military applications. I look at future where GNSS will be more available for military applications. More countries will be authorised to have access to GPS P(Y) code in near future and others will want develop their own SBASs. For example, Nigeria has developed its own SBAS called NIGCOMSAT with coverage only in Nigeria for now. Modernised GPS civil signals will continue to be used by countries not authorised to use P(Y) code. Only, recently, Russian Government inform that GLONASS military signals will be freely made available to any country that want to use them. Already, India and Russian have agreed to collaborate on GLONASS project (Len, 2007 190). It is expected that more Countries will enter into agreements with Russian wh en GLONASS constellation of satellites are fully deployed in the orbit. China is making steady progress on its Compass project and is poised to use the system to strengthen its national security.Finally, GNSS industry is geared for revolution when Galileo is fully operationalised in next few years. Galileo has an encrypted signal PRS which has potentials for military applications. It is already been speculated that this may be used for military applications in the near future, although Galileo is purely conceived as a civilian system.