Pseudolite Options for Improved Mining Navigation

International Global Navigation Satellite Systems Society IGNSS Symposium 2006 Holiday Inn Surfers Paradise, Australia 17 – 21 July 2006

Pseudolite Options for Improved Mining Navigation Garry Einicke Australian GNSS Joint Undertaking at CSIRO Exploration and Mining, PO Box 883, Kenmore, Qld, Australia, Tel: +61 7 3327 4615, Fax +61 7 3327 4566, Email: [email protected]

Sven Martin EADS Strium GmbH, AEN32 (Studies & Navigation Solultions), 81663 Munich, Germany, Tel: +49 89 607 25104, Fax +49 89 607 21023, Email: [email protected]

Michael Voith von Voithenberg EADS Strium GmbH, AEN32 (Studies & Navigation Solultions), 81663 Munich, Germany, Tel: +49 89 607 22687, Fax +49 89 607 21023, Email: [email protected]

Werner Enderle Australian GNSS Joint Undertaking at the Queensland University of Technology 2 George Street, GPO Box 2434, Brisbane 4001, Qld, Australia, Tel: +61 7 3864 1436, Fax: +61 7 3864 1517, Email: [email protected]

ABSTRACT Poor GPS satellite availability limits the opportunities for automation within mining and allied transport industries. For example, in a haul truck automation project, the number of available satellites was observed to decrease as the truck descended down a ramp, commensurate with the reducing view of the sky. The introduction of the Galileo system will ameliorate this satellite availability problem. That is, the presence of two satellite constellations will significantly improve the performance of navigation systems within urban canyon and open cut mining scenarios. This paper describes the mine navigation and localisation requirements and the need for improved accuracy, improved availability, integrity and safety of life services, which will be provided by Galileo. The role of pseudolites, equipment options and spectrum license issues are discussed.

KEYWORDS: Galileo, Augmentation, Pseudolites

1. INTRODUCTION The world’s steadily increasing energy demand is pressuring Australia’s mining industries. Many opportunities exist to improve productivity and safety within mine, rail and port operations. In open cut coal mining, there are two unsolved problems: assisting drivers of heavy trucks to navigate safely, and site-wide management of mine personnel. Some mine incidents are surveyed in Section 2. It emerges that heavy vehicle drivers need to be alerted to the presence of light vehicles, pedestrians and fixed hazards within their local vicinity. In the case of personnel safety, everyone’s location needs to be monitored in a fail-safe manner. This requires system integrity to be reported continuously. The GNSS options are discussed in Section 3. GPS alone does not offer adequate accuracy/availability at mine sites. Signals from GPS satellites are weak. Obstructions such as buildings, bridges, cranes, power poles and trees cause further signal attenuation. Multiple satellite constellations will no doubt improve mine navigation performance. However, GLONASS is currently in a state of disrepair. The Galileo Open Service, combined with GPS, will deliver improved availability. In particular, the results of a study are cited, which indicate for a low rise urban scenario, that 95% availability is predicted for Galileo-GPS versus 50% availability for GPS. The encrypted Galileo Commercial Service will provide extra bandwidth for integrity, a safety of life capability and further accuracy improvement. Some pseudolite options are canvassed in Section 4. Pseudolites are desired at mine sites for two reasons. First, they provide a technological path towards achieving improved availability/accuracy until the Galileo satellites are deployed. Second, they can serve as a permanent augmentation network to provide coverage within deep pits and alongside highwalls.

2. AUSTRALIAN MINING INDUSTRY NAVIGATION AND LOCALISATION REQUIREMENTS

2.1 Mining incidents Mining productivity and safety are inextricably connected. A mine’s license to operate depends, among other things, on good safety management. However, incidents involving trucks and pedestrians continue to occur within Australia’s open cut mining industry. A summary of some Safety Alerts and Significant Incident Reports (NRMW, 2006) is presented in Table 1. I1 I2 I3 I4 I5 I6 I7 I8 I9 I10 I11

INCIDENT a loader was destroyed after being left inside a blast zone (in 2006) a worker who died falling off a highwall remained unnoticed until nightfall (in 2005) An operator was crushed within the articulation point of a loader (in 2003) an excavator made contact within 11 kV overhead power lines (in 2002) trucks were reversed over a bench and driven over dump edges (in 2001) a dozer ran over a light vehicle after the operator of the light vehicle did not receive radio confirmation of his presence from the dozer operator (in 2001) A tele-remote loader ran downwards out of control through its electronic barrier (in 2001) a mine worker was crushed under a coal truck’s rear dump tray (in 2000) a load of overburden was dumped above the working area of a coal crew (in 2000) a light truck crashed over a highwall (in 1999) a head-on collision occurred between two trucks on a haul road beyond the mine lease (in 1999)

Table 1. Summary of Safety Alerts and Significant Incident Reports from (NRMW, 2006).

For convenience, mine safety and productivity GNSS requirements are discussed in two categories:

mine vehicle requirements and mine personnel requirements. 2.2 Heavy vehicle navigation requirements It is believed from the cited mining incidents that heavy vehicle operators would benefit from a navigation aid. This would alert them when the prevailing conditions are likely to be hazardous to themselves or others within their vicinity. That is to say, operators require information about: • the locations of vehicles, and pedestrian crew • local hazards such as dump edges, bench edges, bench walls, overhead power lines and other infrastructure An open cut scoping study (Lever & McAree, 2003) stated requirements for: • a capability to monitor the location, heading, speed, and task of all mobile units within open pit mine, including light vehicles, possibly extending to individual personnel • guidance allowing transit between multiple load and dump zones and operator assists such as safe speeds, distance to vehicles forward and rear, and passing distances Common mine vehicle accident scenarios are heavy-vehicle-heavy-vehicle interactions, heavyvehicle-light-vehicle interactions and heavy-vehicle-pedestrian interactions. Accidents between heavy vehicles (i.e., 75 – 150 t trucks) are the least common. Heavy-vehicle-light-vehicle and heavyvehicle-pedestrian interactions are particularly hazardous. This occurs because heavy vehicle operators have poor visibility and pedestrians may underestimate heavy vehicle manoeuvrability or stopping distances. A consequence of a heavy-vehicle-light-vehicle interaction is shown in Figure 2. Lone pedestrians such as fitters, surveyors, geologists, engineers, supervisors and environmental workers are believed most at risk because safe procedures are probably less practised. Fatigue is the most common cause of accidents along haul roads. Micro-sleeps last for approx 4 to 5 seconds. At a speed of 100 km/h, a driver can travel over 100m during a 4 s micro-sleep.

Fig. 2. Consequence of a heavyvehicle-light vehicle interaction.

Fig. 3. Consequence of leaving a dozer within a blast zone.

Operators of mine vehicles are required to obey site specific rules. For example, giving way to emergency vehicles and at inclines/declines, not overtaking on single lane roads or where there is insufficient clear visibility ahead and maintaining a distance of at least 30 m (say with 10% accuracy) from any vehicles in front. Heavy vehicle drivers have reduced/obscured vision: blind spots can prevent seeing pedestrians and light vehicles within 5 m. That is, personnel located within immediate proximity of heavy vehicles require to be detected with an accuracy of 5 m. Reversing and manoeuvring in congested locations require extreme care. Restricted areas such as hazardous infrastructure (e.g. powerlines, dump edges), mixed traffic, workings, blast areas and designated environmentally sensitive areas must be avoided. Drivers have to contend with fatigue, wet weather, poor visibility, night-time and changing traffic conditions (e.g. breakdowns). Typically, there is at least 2 m clearance between a heavy vehicle and the edge of a haul road, which suggests a positional accuracy requirement of 2 m. The current boom in the Australian mining industry is tempered by skill shortages and high equipment maintenance costs. It is a challenge for mines to recruit sufficiently skilled personnel and

accommodate them locally. Any lost time injuries exacerbate the problem. Mine vehicles that sustain damage are unproductive when they are taken out of service for maintenance. For example, haul trucks can subside when driven over unstable ground, such as unrecognised creek beds or old workings. The expense of vehicle retrieval, repair (e.g. tires cost $20,000 each) and injuries to personnel are not inconsequential. It is suggested than a positional accuracy of 2 m is a minimum requirement when assisting heavy vehicle operators to navigate around known hazards. In an ACARP project, entitled Introduction of Autonomous Haul Trucks (Hughes, 2001), severe difficulties were encountered with reliance on a GPS system. Some problems that were reported include: • a lack of GPS satellite availability around the bench caused stoppages • deficiencies in the communication system resulted in outages • the collision avoidance system was inadequate In particular, the final project report contains the following statements. • “The number of available satellites was observed to decrease as the truck descended down a ramp, and the wall height increased, and the ramp width limited the view of the sky. This was associated with an increase in dilution of precision. When six or more satellites were visible and differential corrections were received, the GPS accuracy was typically less that 30 mm.” • “Throughout the testing the minimum number of satellites available to the truck was four, enough to stop autonomous operation through ‘lack of satellite availability’.” • “The operational testing provided no conclusive results for the maximum wall heights/pit widths to enable continuous autonomous travel.” • “Prolonged delays in communicating GPS differential correction data resulted in a slow down or stopping of the truck.” • “The automated trucks tend to stop for numerous reasons such as a false alarm on a collision avoidance system, requiring the pit controller to inspect the situation and contact the central operator to confirm that the situation is safe before restarting.” In another ACARP project report (Hall and Bryant, 1997), it is noted that close to highwalls (i.e., within 3 - 4 m), depending on the positioning of the satellites at any given time, a GPS system was observed to drop back to two dimensional fixing, with only three satellites visible. It follows from the above-mentioned ACARP reports, that limited GPS availability becomes a critical problem at mine sites whenever the view of the horizon is severely masked. Under these conditions, inertial navigation systems could be used to compensate for deficiencies in GNSS performance. It is suggested that the system availability at mine sites should be better than 50%. VEHICLE NAVIGATION REQUIREMENTS Accuracy • The system shall detect the presence of pedestrians and light vehicles in the vicinity of stationary heavy vehicles with an accuracy of 2 m. •

Availability

•

Integrity Safety of life

• •

The system shall detect the presence of pedestrians and light vehicles within the stopping distance of mobile heavy vehicles. The system availability at mine sites shall be better than 50% The system shall report integrity information The system shall have a safety of life facility

INCIDENTS I9, I3 & I8

I6

All All I3, I5, I6, I8, I10 & I11

Table 2. Vehicle navigation requirements.

The introduction of systems to assist in managing safety can result in a work place culture that becomes dependent on those systems. It follows that there is an increased safety risk when the safety systems suffer integrity problems. Therefore, any mine safety system needs to continuously send integrity confirmation. When vehicle drivers are involved in an accident, they will need, among other things, an emergency communications link to the nearest mine rescue crew. The vehicle navigation requirements, cross-

referenced to the mine incidents cited in Table 1, are summarised in Table 2. 2.3 Mine pedestrian localisation requirements The previous section outlined some requirements for a navigation aid to assist heavy vehicle drivers. There are additional needs to manage the safety of pedestrians at open cut mine sites. Some circumstances that need to be considered include: • personnel working in areas beyond the available communications range; • personnel working in close range to hazards, and • whenever communications equipment failures occur. Underground mine localisation systems typically involve tags, which transmit identification information and readers which receive the information from tags, see (Einicke, 2003) and (Einicke and Wilson, 2005). This technology is widely known as radio frequency identification (RFID). RFID readers tend to be installed sparsely, say at the portals and along the main traffic routes. Tracking software, such as the NexSysTM real time risk management system (Einicke and Rowan, 2005), running in the control room, reports the last known location of personnel and vehicles. As a minimum, an open cut mine personnel localisation system should similarly report last-known-location information. In an open cut mining context, portals are ill-defined and can extend to the boundary of the mine lease. Often it is impractical to provide communications coverage over the entire mining lease. Mine environments are dynamic - the location of hazardous zones follows the development of the mine. For example, a consequence of leaving a dozer within a blast zone is shown in Figure 3. A system to assist in the management of site-wide personnel safety should include the following: • constructing physical barriers (such as fencing) • installing communications equipment for surveillance of the remaining regions • implementing electronic barriers (e.g., to delineate the operational envelopes of tele-operated equipment and blast zones) • establishing protocols in which roving personnel periodically establish communications connectivity • for cases where the above measures are not practical, providing satellite communications or other safety of life systems for lone workers in remote areas For example, it is suggested that fencing is erected to limit mine-site entry/exit to gate houses and haul roads, where electronic monitoring systems are installed. Protocols can then be established where work crew report to the control room within agreed time intervals. Alarms and trigger response actions can then be initiated whenever reporting time-outs are detected. Communicating this time-out information is commonly known as exception reporting. PERSONNEL LOCALISATION REQUIREMENTS Accuracy • The system shall report the last known location of pedestrians • Availability

•

Integrity Safety of life

• •

The system shall report the presence of pedestrians within electronic barriers The system availability at mine sites shall be better than 50% The system shall report integrity information The system shall have a safety of life facility

INCIDENTS I2

I1, I7 All All I2

Table 3. Personnel localisation requirements.

The OH&S implications of the whole-of-body-vibration experienced by dozer operators has prompted the introduction of tele-operated loaders to mine sites. Tele-operated and other hazardous equipment need to revert to a safe mode whenever pedestrians breach the local electronic barrier. For example, brakes should be applied whenever pedestrians are located within the swing radius/turning radius or stopping range of dozers and heavy vehicles. Further, worst case scenarios must be assumed whenever equipment failures occur. Systems which revert to a safe mode when failures are detected

are known as fail-safe. For example, remote controllers for tele-operated equipment are required to be fail-safe. The standards for fail safe systems include: AS 4024 Safe guarding of machinery, AS 61508 Functional safety of electrical/electronic/programmable electronic safety-related systems, and EN 954 Safety of machinery. Fail safe systems require integrity data fed back to interlock circuits that provide appropriate protection. To best knowledge of the authors, there are no fail safe GNSS systems currently available in the marketplace. However, a system could be designed using the principles of AS 4024, AS 61508 and EN 954, in which integrity data is fed back into exception reporting decisions. The personnel localisation requirements are summarised in Table 3.

3. GNSS OPTIONS FOR MINING NAVIGATION AND LOCALISATION The NAVstar System with Timing and Ranging (NAVSTAR) Global Positioning System (GPS) was developed by the USA Department of Defense (DoD) to meet military needs. The first Block I GPS satellite was launched in 1978. The 24 Block II satellites are organised in six orbital planes at an altitude of 26,600 km above the earth, and were declared fully operational in 1995. There are a further 4 spare GPS satellites in orbit. In 1995 the Russian Space Force had deployed a 24-satellite GLObal NAVigation Satellite System (GLONASS) in three orbital planes at an altitude of 19,100 km. A horizontal accuracy (95% probability) of 28 m and vertical accuracy of 60 m are claimed (Polishchuk and Revnivykh, 2004). The GLONASS satellites have a 2.5 year design life. There was an absence of sufficient funding during 1996 – 2001, and in 2004, there were 7 operational satellites (Polishchuk and Revnivykh, 2004). The European Union launched the first in-orbit-validation Galileo satellite in 1995. The full Galileo constellation of 27 active satellites and 3 spares should be deployed in three circular Medium Earth Orbit planes at 23,616 km altitude by 2010. Galileo covers various GPS shortfalls and offers several critical advantages (Feng, 2003) as set out below. • Higher altitude orbits (compared with GPS) will provide improved satellite visibility and system availability. • The free Open Service (OS) will be more accurate due the combination of increased signal strengths, reduced code noise level, improved ionospheric models, improved tropospheric models, more frequently updated clocks and orbits, and more accurate satellite clocks. • The Commercial Service (CS) will be available for a fee and provide integrity data and alarms to warn users of malfunctions; • Galileo provides service guarantees for commercial users in terms of accuracy, availability, continuity and integrity. • The CS will include a safety of life service by detecting alerts and communicating with safety and rescue operations. • In addition to the two carriers used for the OS, the encrypted CS will allow the use of a third carrier that results in an accuracy of less than 1 m.

Analysis scenario and constellation

Open sky Suburban Low-rise High-rise

Accuracy / availability – satellites only 28 GPS only 28 GPS + 27 (m/%) Galileo (m/%) 7/95 4/95 32/90 8/95 17/50 14/95 42/90

Accuracy / availability differential 28 GPS + 27 Galileo (m/%) 1.5/95 4/95 7/95 25/90

Table 4. Summary of predicted performance improvements resulting from using both Galileo and GPS (Blomenhofer et al, 2003).

Global availability (%) Horizontal positioning accuracy (m) Vertical positioning accuracy (m) Timing accuracy wrt UTC (ns)

Single frequency 99.5 15 35 30

Dual frequency 99.5 4 8 4230

Table 5. Selected performance parameters for the Galileo OS, using one and two frequencies (Trautenberg et al, 2004).

The combination of Galileo and GPS constellations will yield improved accuracy and availability compared to GPS alone. Further, the EU and the USA DoD have signed agreements on the use of a common time reference and complementary frequencies for interoperability and redundancy. There have been various endeavours to quantify the improved accuracy and availability that will eventuate from combined Galileo and GPS GNSS systems, and some representative approaches are cited here. The result of a Galileo performance study (Blomenhofer et al, 2003) is shown in Table 4. This study predicts that under open sky conditions, a combined Galileo and GPS system will offer 4 m accuracy, compared to 7 m for GPS. In the low-rise urban case, the availability improves from 50% (for GPS) to 95% (for GPS and Galileo). Some further estimates of the Galileo OS performance are reported in (Trautenberg et al, 2004), which are shown in Table 5. Simulations that estimated the horizontal dilution of precision (HDOP) based on worldwide satellite and user receiver geometries are presented in (O’Keefe et al, 2004). The predicted worldwide HDOP for GPS only and combined Galileo/GPS satellite constellations are shown in Figures 4 and 5 respectively. These figures suggest an improvement from 1 – 1.2 HDOP to 0.6 – 0.8 HDOP would be realised by the combined constellation system.

Fig. 4. Predicted worldwide GPS only availability expressed by 95% percentile HDOP value (O’Keefe et al, 2004).

Fig. 5. Predicted worldwide Galileo and GPS availability expressed by 95% percentile HDOP value (O’Keefe et al, 2004).

In respect of the mining GNSS requirements (summarised in Tables 2 and 3), GLONASS is not an option until the funding becomes available to repopulate the constellation. A major problem with GPS is the lack of availability. For example, in Kansas City it has been observed that five or more GPS satellites are only available six hours per day, and those six hours are fragmented throughout the day, making GPS RTK impossible to use (Van Diggelen, 1997). In the simulations of (O’Keefe, 2001), an availability measure is calculated, namely the fraction that the HDOP is less than 2, and the results are shown in Figure 6. The figure indicates that for 40 degree elevation masking angles (which often occurs within pits at mine sites), both GPS alone and Galileo alone cannot provide at least 50% availability, whereas a combined Galileo-GPS system can. Another limitation of GPS is the lack of integrity information. As explained in Section 2, users

require information about when the system is malfunctioning, for example, when a satellite ceases to be operational, or a spare is moved into orbit and activated. Indeed, failures of a GPS satellite has been reported (Cobb and Lawrence, 1995). A threat to all satellites is space junk – there are about 105 inoperable GLONASS satellites and uper stages drifting in their original orbits; as a result of eccentricity growth, these orbits, including the future disposal of Galileo, may intersect the orbits of operational navigation constellations (Chao and Gick, 2004). Therefore, the provision of integrity data is a mandatory requirement. The GPS Block II satellites do not provide a safety of life capability. Thus from safety of life, integrity, availability and accuracy perspectives, a combined Galileo CS and GPS system is required for the afore-mentioned mining applications – this conclusion is indicated by Table 6. Mine Requirement

GPS

GLONASS

GPS + GLONASS

Galileo OS

Galileo CS

2 m accuracy 50% availability Integrity Safety of life

2 2 2 2

2 2 2 2

2 2 2 2

2 2 2 2

3 2 3 3

Galileo CS + GPS 3 3 3 3

Table 6. Reconciliation of mine requirements with GNSS options.

4. PSEUDOLITE OPTIONS FOR MINING NAVIGATION AND LOCALISATION The full Galileo constellation is expected to be deployed by 2010. In the interim and beyond, GPS and Galileo satellites can be augmented by pseudolites. Pseudolites are land-based transmitters or beacons that broadcast satellite-like signals to augment those from GPS, GLONASS and Galileo satellites. Traditional GPS with independent pseudolites installed at precisely known locations have been widely described, see (Stone et al, 1999) and the references therein. In a surface mining context, steep pit walls can introduce masking angles of 45 degrees, which reduces satellite visibility, increases the Dilution of Precision, and degrades system availability. This can be mitigated by installing pseudolites at the tops of highwalls as is shown in Figure 7.

Fig. 6. Percentage of HDOP values (worldwide) less than 2 for GPS, Galileo and the combined systems (O’Keefe et al, 2001).

Fig. 7. Side view of open cut mine with pseudolites (Stone et al, 1999).

The frequencies used by GPS, GLONASS and Galileo are shown in Figure 8. Electromagnetic spectrum usage within Australia is managed by the Australian Communications and Media Authority, see http://www.acma.gov.au. It is in fact illegal to operate a pseudolite that transmits on the L1 GPS frequency because this will interfere with the GPS signals. In particular, there are offense provisions in the Radiocommunications Act 1992 http://www.comlaw.gov.au/comlaw/legislation/actcompilation1.nsf/0/F57C95B49E6C4672CA257026 002532D2/$file/RadiocommnsAct92_WD02.pdf. In addition, there is in place a prohibition on

jammers of GPS and related services at http://www.acma.gov.au/acmainterwr/aca_home/legislation/radcomm/declarations/radpd_rnssjam_dec 04.pdf. Pseudolite equipment which does not operate on the L1 band includes: • Locata; • Novariant, and • Astrium EADS. Locata Corporation’s system is described in (Barnes et al, 2003). Their pseudolites are called LocataLites, which transmit on the unlicensed 2.4 GHz ISM band. Self-jamming is avoided by ensuring that multiple LocataLites do not transmit at the same time. In an indoor static test, 1 s updates were reported with sub cm accuracy (Barnes et al, 2003). In the Novariant system (Novariant, 2006), the pseudolites are termed Terralites, which operate over 902 – 928 MHz and have an output power of 1 W. Frequency hopping spread spectrum is employed to accommodate multiple Terralite signals. In a typical mine application, Novriant suggest that GPS is augmented by 4 – 12 Terralite Transmit Stations and one Terralite Reference Station (Novariant, 2006).

Fig. 8. GPS, GLONASS and Galileo frequency usage (Lindstrom and Gasparini, 2003).

The Locata and Navariant receivers do not possess E5ab and E6 front-ends, whereas EADS Astrium has produced Galileo compatible equipment (EADS Space, 2006). The output frequency of the socalled GNSS Signal Generator NSG 5100 is switchable between E5ab, L1 and E6. The nominal output power range is -63 – 0 dBm and -152 dBW can be reached via an additional attenuator. Needless to say, the NSG 5100 cannot be operated on the L1 frequency within Australia. However, at this time, the ACMA can consider issuing a licence for devices transmitting on E5ab and E6 frequencies. The design and operation of pseudolites require management of the so-called near-far problem. If a pseudolite’s transmit signal power is matched to that of received satellite signal at one range, it may dominate at a shorter range or it may be too weak at a longer range. One way of dealing with this near-far problem is to pulse the pseudolite transmissions. Pulsing the transmitter outputs also allows GNSS receivers to acquire signals from both satellites and pseudolites. There are two relevant pulsing standards, namely RTCA and RTCM. The NSG 5100 has RTCA, RTCM and user-definable pulsing options. The RTCA scheme is discussed in Van Dierendonck (1997), in which an independent pseudorandom sequence controls the pulse repetition rate, resulting in pseudolite signal duty cycles of around 2%. Pulse collisions occur with this mechanism, which amount to a loss of 0.085 dB per pseudolite for a 2% duty cycle (Van Dierendonck ,1997). In the RTCM specification, a GPS-like gold-code generator produces the pseudo-random code sequence to pulse the pseudolite output, with duty cycles of around 10% (Stansell, 1986).

GNSS receivers for the E5ab, E6 and L1 bands have recently been developed. The key differences between Galileo and GPS receivers are explained in Hollreiser (2004). Septentrio has developed receivers for the Galileo satellites, Galileo ground stations and consumer applications (Simsky et al, 2005). For example, the nominal vertical and horizontal position accuracies for the GENeRx1 GPS/Galileo Receiver are 1.9 m and 1.1 m respectively (Septentrio, 2005). The architecture of IFEN’s combined Galileo-GPS receiver is reported in (Schmid et al, 2005). The above-mentioned Galileo signal generator and receiver technologies are mature and suitable within pseudolite systems for mine sites. A network of nine such pseudolites is being established in southern Germany to provide coverage over an area of 65 km2 (Lechner, 2006). The system is called GATE, which is an abbreviation for "Galileo Test- und Entwicklungsumgebung" (Galieo Test- and Development Environment). The GATE system provides an environment for developing and testing GNSS applications.

5. CONCLUSIONS The increasing global energy demand is pressuring Australia’s mining and allied transport industries. GNSS technologies can be integrated within automation solutions to reduce supply problems within mine, rail and port operations. This paper discusses the application of GNSS to improve productivity and safety at open cut coal mines. The mine requirements are discussed in two categories: vehicle navigation and personnel localisation. Drivers of heavy mine vehicles require knowledge about the presence of light vehicles, pedestrians and fixed hazards within their vicinity. Managing personnel safety at mine sites requires up-to-date knowledge of everyone’s whereabouts. Solutions based on GPS alone will not adequately meet these requirements. The Galileo CS includes the provision of extra bandwidth for improved accuracy, integrity and safety of life capabilities. Arguably, the Galileo CS in combination with GPS, will better match the mine requirements. In the interim, during the deployment of Galileo, and beyond, augmentation can be achieved via Galileo-compatible pseudolites, and some equipment options are discussed.

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