The Best of Two Worlds: GPS LoranC Snugly Together in a PocketPCsized Device

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The Best of Two WorldsGPSLoran-C Snugly
Together in aPocketPC-sized Device

• A.W.S. Helwig, G.W.A. Offermans, W.J. Pelgrum, R.
  Kellenbach and D. van Willigen
• Reelektronika b.v. / Reeuwijk / The Netherlands
• GNSS 2003
• Graz, Austria, 22-25 April 2003

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Contents

• Breakthrough in Loran-C performance
• 2,000 km datalink performance
• Extremely fast start-up
• Integration with GNSS
• Continuous calibration of Loran-C ranges
• Static/dynamic trials
• Development of a small integrated receiver

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Third generation prototype
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Interference Mitigation
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2,000 km Range Eurofix
9007X (Bø) Lost Eurofix Message Probability vs
SNR
Ankeveen (NL), September 13-14, 2002
100
5000
90
4500
80
4000
70
3500
Messages
60
3000
Lost Message Probability
Lost Eurofix Message Probability ()
of Messages Received per 0.5 dB
2500
50
40
2000
1500
30
20
1000
10
500
0
0
12
14
16
18
20
22
24
26
SNR (dB)
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2,000 km Loran-C Navigation
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2,000 km Range Benefits

• Polar flights offer reduced flight time, saves
  fuel and, relieves Atlantic Ocean slot crowding
• In Polar Region no Geostationary SBAS or
  communication available
• Communication solved by HF radio
• Navigation based on GPS and IRS
• GPS integrity to be solved by extended range
  Eurofix

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Polar Routes

• Restricted Russian polar routes Polar 1 to 4
• Preferred random routing in Canada
• 2005 9000 commercial polar flights estimated
• Savings
• Flying time 2 hrs
• Costs US 16 k/flight
• Time slots Atlantic
• Polar Routes Feasibility Study, Nav Canada and
  FAAR, October 2000

Polar 4
Polar 3
Polar 2
Polar 2A
Polar 1
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Polar Eurofix

• Estimated Eurofix coverage
• Larger ground wave attenuation
• Less atmospheric noise
• Less Cross-rate
• Less CWI (continuous wave interference)

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Functional Diagram GLORIA Integrated Navigation
Receiver
H-field antennas (Reelektronika)
GPS antenna (NovAtel)
GPSReceiver
Loran-C ReceiverLORADD
LORADD(Reelektronika)
GPS receiver(NovAtel)
IntegrationSoftware
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Measurement Campaign LORADD
Reelektronika test vehicle
GPS Antenna
LORADD Antenna
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Measurement Campaign LORADD
Play movie
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Measurement Results LORADD
Paris, in Carpark, F, 4-9-2002
2 floors below ground
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Measurement Results LORADD
Paris, in Carpark, F, 4-9-2002
Accuracy 72 m (95) !
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Measurement Results LORADD
Reeuwijk, NL, 28-8-2002
Small axis 5 m (95)
Long axis 85 m (95)
Accuracy 74 m (95)
Loran-C Geometry in Netherlands is BAD!
Potential Loran-C positioning accuracy
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Measurement Results LORADD
Reeuwijk, NL, 28-8-2002
Long axis 85 m (95)
Loran-C Geometry in Netherlands is BAD!
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Measurement Results LORADD
Munchen, D, 12-6-2002
Accuracy 33 m (95)
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Measurement Results LORADD
Paris, Eiffel tower, F, 5-9-2002
Accuracy 14 m (95)
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Development of a small integrated Rx

• Co-operation with NELS
• Contractual delivery XXXX (november?)
• Integrated receiver consists of
• Miniaturised Loran-C receiver
• H-field Loran-C antenna
• Miniaturised GPS receiver and antenna
• Integration software (runs in parallel on the
  Loran-C DSP)

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Components of a small integratedLoran-C/GPS
receiver

• DSP board (approx. 80x80 mm)
• Daugther board (same size as DSP board)
• Loran-C front-end A/D converter
• GPS core module
• Total 2 boards 80x80x20 mm
• Available Q4 2003

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Conclusions

• Extended range of Loran-C/Eurofix opens up the
  possibility for new applications, such as
  WAAS/EGNOS derived integrity in Polar Region and
  urban areas
• Integrated GPS/Loran-C offers continued
  positioning in areas where GPS fails
• The development of miniaturised receivers is well
  underway. Commercial availability from Q4 2003.