A Novel GNSS Avionics-Based Integrity Augmentation System

A Novel Avionics Based GNSS Integrity

Augmentation System

Assoc. Prof. Roberto Sabatini (RMIT University, Australia)

Prof. Terry Moore (University of Nottingham, United Kingdom)

Dr. Chris Hill (University of Nottingham, United Kingdom)

Melbourne, 16th December 2013

International Conference on Aeronautical

and Astronautical Engineering (ICAAE)

Space Based Augmentation Systems (SBAS)

Ground Based Augmentation Systems (GBAS)

Avionics Based Augmentation Systems (ABAS)

GNSS Augmentation

(Integrated Navigation Systems)

ACCURACY

INTEGRITY

AVAILABILTY

CONTINUITY

A/Prof. R. Sabatini RMIT University – School of Aerospace, Mechanical & Manufacturing Engineering 2

GNSS augmentation benefits in aviation include:

• Increased Runway Access

• More direct en route flight paths

• New precision approach services

• Reduced and simplified equipment on board aircraft

• Potential elimination of some ground-based navigation aids (NDB, VOR, ILS, etc.) with cost saving to ANSPs

In addition to SBAS and GBAS, GNSS augmentation may take the form of additional information being provided by other avionics systems. The additional avionics systems operate via separate principles than the GNSS and, therefore, are not subject to the same sources of error or interference

A system such as this is referred to as an Aircraft (or Avionics) Based Augmentation System (ABAS)

ABAS


There are very good reasons to augment GNSS in mission- and safety-critical manned aircraft applications (i.e., GBAS, SBAS, ABAS)

There are certainly even better reasons to augment GNSS in UAS applications

In UAS applications (as in manned safety-critical applications) there is a strong focus on Integrity Augmentation Requirements

UASs clearly require some forms of Avionics Based Integrity Augmentation (ABIA) to allow an extended spectrum of autonomous and safety-critical operations

ABAS/ABIA


During flight test activities with GNSS TSPI and Integrated Position Reference Systems (PRS), it was observed that one or more of the following conditions was prone to cause TSPI data outages:

• The aircraft reaching Critical Attitude Angles (CAA)

• Bad satellite geometries and low satellite C/N0

• Aircraft Data Link (ADL) antennae coverage (real-time telemetry)

• Interference, at the airborne GPS antenna, caused by the Radio Systems or other Intentional/Unintentional RF signals

• Multipath caused by GNSS signals reflected by the Earth/Buildings or the aircraft body surfaces

It is evident that these limitations do not apply to TSPI GNSS systems only, but they hold true for other high integrity (and high accuracy) applications of GNSS, such as precision approach, landing, military weapon aiming, etc.

In our research, we developed a novel Avionics Based Integrity Augmentation (ABIA) system, specifically targeting GNSS Mission- and Safety-Critical Applications

GNSS TSPI Data


First ABIA prototype system for mission-critical GNSS applications (Flight Test, Flight Inspection, etc.) [1]

• The aircraft sensors provide information on the aircraft relevant flight parameters to an Integrity Flag Generator (IFG), which is also connected to the on-board GNSS

• Using the available data on GNSS and the aircraft flight parameters, integrity signals are generated which can be displayed on one of the cockpit displays and/or sent to an Aural Warning Generator (AWG)

TSPI-ABIA


ABIA Evolution for Aircraft and Unmanned Aircraft (Mission and Safety-Critical GNSS Applications)

ABIA Evolution


Caution Integrity Flag (CIF):

A predictive annunciation that the GNSS data delivered to the avionics system

is going to exceed the Required Navigation Performance (RNP) thresholds

specified for the current and planned flight operational tasks (GNSS alert status)

Warning Integrity Flag (CIF): A reactive annunciation that the GNSS data delivered to the avionics system

has exceeded the Required Navigation Performance (RNP) thresholds specified

for the current flight operational task (GNSS fault status)

ABIA Time-to-Caution (TTC): The minimum time allowed for the caution flag to be provided to the user

before the onset of a GNSS fault resulting in an unsafe condition

ABIA Time-to-Warning (TTW): The maximum time allowed from the moment a GNSS fault resulting in an

unsafe condition is detected to the moment that the ABIA system provides

a warning flag to the user

A

L

E

R

T

S

T

T

A

ABIA Key Definitions


• Obscuration

• Bad satellite geometry (DOP)

• Fading (low C/N0)

• Doppler shift (signal tracking, acquisition time)

• Multipath effect (C/N0, range and phase errors)

• Interference and Jamming

Causes of GNSS data degradation or loss (A/C level):

Understanding the physics of these phenomena and developing reliable mathematical models was essential in order to properly design the GNSS ABIA system

GNSS Threats


IFG Architecture

Integrity Processing Layer

Data Extraction Layer

GNSS and Sensors Layer

GNSSAircraft

Sensors

Caution and Warning Integrity Flags

A/C 3D Model Terrain and

Objects

Navigation and

Flight DynamicsGNSS

Constellation

Databases Avionics Data

Signal Analysis

Module

Doppler Analysis

Module

Obscuration

Analysis ModuleMultipath Analysis

Module

Caution and Warning Thresholds


Due to the flight manoeuvres, the aircraft body (wings, tail and fuselage) obscure some satellites

A 3D CAD model is used to determine the Antenna Masking Matrix (AMM) with varying pitch, roll and yaw

A library of AMMs (Total Masking Envelope – TME) is loaded in the ABIA IFG software for automatic real-time identification of the masked satellites

AEROSONDE Antenna Masking Matrix (Roll=450) AEROSONDE Antenna Masking Matrix (Pitch=450)

Antenna Obscuration


TME Example

0

30

60

90

0 60 120 180 240 300 360

Ele

va

tio

n-d

eg

ree

Azimuth-degree

B90 B85 B80 B75 B70 B65 B60 B55 B50 B45 B40 B35

B30 B25 B20 B15 B10 B5 P90 P85 p80 P75 P70 P65

P60 P55 P50 P45 P40 P35 P30 P25 P20 P15 P10 P5

INVISIBLE

VISIBLE


(B = bank and P = pitch - All angles are in degrees)

CIF/WIF Thresholds

CIF and WIF

Thresholds

Relative

Geometry

Radio

Frequency

Receiver

Tracking

Antenna Masking

Position Accuracy

PLL Tracking

FLL Tracking

Masking Matrixes

Estimated HPE/VPE

Rx Tracking Errors

DLL Tracking

Multipath

Link Budget

Interference

C/N0 Calculation

J/S Calculation

Doppler Shift

Phase/Range Errors

Frequency Error


CIF/WIF Criteria

Satellite-A/C Relative Geometry

• When the current A/C manoeuvre will lead to less the 4 satellite in view, the CIF shall be generated

• When only 4 SV are in view and one (or more) satellite(s) elevation angle is less than 10 degrees, the caution integrity flag shall be generated

• When less than 4 satellites are in view, the WIF shall be generated.

• When only 4 SV are in view and one (or more) satellite(s) elevation angle is less than 5 degrees, the warning integrity flag shall be generated


CIF/WIF Criteria

Positioning Errors

• When the Estimated Horizontal Error (EHE) exceeds the required Horizontal Accuracy 95% or the Estimated Vertical Error (EVE) exceeds the required Vertical Accuracy 95% alert requirements, the CIF shall be generated

• LAAS assisted GLS approach:

− When the Predicted Lateral Protection Level (PLPL) exceeds Lateral Alert Limit (LAL) or the Predicted Vertical Protection Limit (PVPL) exceeds the Vertical Alert Limit (VAL), the CIF shall be generated

− When the Lateral Protection Level (LPL) exceeds the LAL or the Vertical Protection Level (VPL) exceeds the VAL, the WIF shall be generated

• When the EHE exceeds the LAL or the EVE exceeds the VAL, the WIF shall be generated


CIF/WIF Criteria

Radio Frequency Link Thresholds

• Multipath:

− When the Early-Late-Phase (ELP) exceeds 0.1 radians, the caution flag for multipath shall be generated [17, 18]

− When the multipath ranging error shows a sudden increase with the A/C flying in proximity of the ground (below 448.5 metres), the warning integrity flag shall be generated.

− When the multipath ranging error exceeds 2 metres and the A/C flies in proximity of the ground (below 500 ft AGL), the warning integrity flag shall be generated (*)

• Doppler:

− When the C/N0 is below 28 dB-Hz and the signal is lost, the caution integrity flag for Doppler shall be generated if the estimated acquisition time is less than the application-specific TTA requirements (*)

− When the C/N0 is below 28 dB-Hz and the signal is lost, the warning integrity flag for Doppler shall be generated if the estimated acquisition time exceeds the application-specific TTA requirements (*)

(*) Criteria based on GPS receiver flight test


CIF/WIF Criteria

Receiver Tracking Thresholds

• When the signal tracking errors are within 5% of the maximum error budget tolerated by the receiver [13, 19, 20, 21], the CIF shall be generated

• When the signal tracking loss conditions occur [13, 19, 20, 21], the WIF shall be generated.

• When the C/N0 is less than 26 dB-Hz the CIF shall be generated (*)

• When the C/N0 is less than 25 dB-Hz the WIF shall be generated (*)

(*) Criteria based on GPS receiver flight test


IFG Simulator

Integrity Flags Processing


Objects

Navigation and Flight

DynamicsGNSS

Constellation

Databases Simulators

Signal Analysis

Module

Doppler Analysis

Module

Obscuration


Module




TORNADO upper antenna location:

TORNADO 2D Drawing [6]

TORNADO 3D CAD model

Fantenna = Fbody + Tbodyantenna (m)

Tbodyupper

= −0.88

0−0.74

(m)

Length 16.72 m (54 ft 10 in)

Wingspan 13.91 m at 25° wing sweep, 8.60 m at 67° wing

sweep (45.6 ft / 28.2 ft)

Height 5.95 m (19.5 ft)

Wing area 26.6 m² (286 ft²)

ABIA Simulation


ABIA Simulation

Selected Platform: AEROSONDE UAS [22]

GPS Antenna

Tbody = 0.341.690.43

(m)


IFG Simulation

CAD Models and Masking Analysis

0

30

60

90

0 60 120 180 240 300 360

Ele

va

tio

n-d

eg

ree

Azimuth-degree

B90 B85 B80 B75 B70 B65 B60 B55 B50 B45 B40 B35

B30 B25 B20 B15 B10 B5 P90 P85 p80 P75 P70 P65

P60 P55 P50 P45 P40 P35 P30 P25 P20 P15 P10 P5

INVISIBLE

VISIBLE


AEROSONDE-UAS Case Study

CAD Model and Masking Analysis


−1500

−1000

−500

0

500

1000

1500

−1500

−1000

−500

0

500

1000

−400

−200

0

200

400

600

−10000

10002000

3000

−2000

−1000

0

1000

2000

−500

0

500

1000

1500

2000

2500

Stereo-Lithography (STL) Format


AEROSONDE-UAS Case Study

IFG Simulation

AEROSONDE UAS CAD Model and Masking Analysis

0

30

60

90

0 60 120 180 240 300 360

Ele

va

tio

n-d

eg

ree

Azimuth-degree

B90 B85 B80 B75 B70 B65 B60 B55 B50 B45 B40 B35

B30 B25 B20 B15 B10 B5 P90 P85 p80 P75 P70 P65

P60 P55 P50 P45 P40 P35 P30 P25 P20 P15 P10 P5

INVISIBLE

VISIBLE

−10000

10002000

3000

−2000

−1000

0

1000

2000

−500

0

500

1000

1500

2000

2500


Both 6-DOF and 3-DOF flight dynamics model with variable mass can be used for the Flight Dynamics Simulator (FDS)

The different flight phases (and associated manoeuvres) are considered: Taxi, Climb, Cruise, Turn and Climb, Turn and Descent, Approach

IFG Simulation


TORNADO aircraft trajectory:

• Climb flight phase (0-5min)

• Cruise (straight-and-level) flight phase (5-10min)

• Turn and descend flight phase (10-5min)

• Cruise flight phase (15-20min)

• Approach (straight descent) flight phase (20-25min)

Initial point of the A/C trajectory located at LHR airport (WGS coordinates: 51° 28′ 39″ N, 0° 27′ 41″ W)

GPS constellation simulated using the YUMA almanac data

Flat terrain profile and free from man-made features

GLS in the presence of LAAS was simulated

TORNADO Case Study


GPS receiver characteristics:

• Random vibration power curve is flat from 20Hz to 2000Hz with an amplitude of 0.005 g2/Hz

• Oscillator vibration sensitivity is 10-9 parts/g

• Third-order loop noise bandwidth is 18Hz

• The maximum LOS jerk dynamic stress is 10 g/s = 98 m/s3

The CIFs and WIFs relative to antenna masking, geometric accuracy degradations, C/N0, multipath and Doppler shift were generated

TORNADO Case Study


Phase 1 2 3 4 5

Trajectory Climb Cruise Turn &

Descent

Cruise Approach

Duration 5min 5min 5min 5min 5min

Satellites in

view

16

Prn.1,3,6,

7,9,11,12,

13,14,15,

22,23,26,

27,30,31

16

Prn.1,3,

6,7,9,11

,12,13,1

4,15,22,

23,26,2

7,30,31

16

Prn.1,3,6,7,9,

11,12,13,14,1

5,22,23,26,27,

30,31

16

Prn.1,3,6,7

,9,11,12,13

,14,15,22,2

3,26,27,30,

31

16

Prn.1,3,6,7,9,11,

12,13,14,15,22,2

3,26,27,30,31

Caution

flag

-

-

600~608s

672~ 698s

762~788s

852~878s

-

1484~1500s

Warning

flag

-

-

674~692s

764~782s

854~872s

-

1490~1500s

DOP

caution flag

- - - - 1484~1500s

DOP

warning flag

- - - - 1490~1500s

Phase 1 2 3 4 5

Trajectory Climb Cruise Turn&

Descent

Cruise Approach

Duration 5min 5min 5min 5min 5min

Obscuration

caution flag

0~300s

Prn.30

300~600s

Prn.30

Prn.3,6,11,12,

13,14,15,22,2

3,26

900~1200s

(Prn.30)

1200~1500s

Prn.30

Obscuration

warning flag

- - Prn.3,6,11,12,

13,14,15,22,2

3,26

- Prn.30

1210~1236s

1254~1500s

SNR caution

flag

0~300s

Prn.1,3,9,11,

12,13,30

300~600s

Prn.1,3,9,11,12,

13,30

600~900s

Prn.1,3,12,13,

30

900~1200s

Prn.1,3,9,11,1

2,13,30

1200~1500s

Prn.1,3,9,11,12,

13,30

SNR warning

flag

0~300s

Prn.1,3,11,1

2,13,30

0~50s

Prn.9

300~600s

Prn.1,3,11,12,13

,30

600~900s

Prn.1,3,12,13,

30

900~1200s

Prn.1,3,11,12,

13,30

1200~1500s

Prn.1,3,11,12,1

3,30

Multipath

caution flag

0~300s

Prn.1,3,7,9,1

1,12,13,30

300~600s

Prn.1,3,7,9,11,1

2,13,

30

600~900s

Prn.1,3,7,9,11

,12,13,30

900~1200s

Prn.1,3,7,9,11,

12,13,

30

1200~1500s

Prn.1,3,11,12,1

3,30

Multipath

warning flag

0~300s

Prn.1,3,7,9,1

1,12,13,30

300~600s

Prn.1,3,7,9,11,1

2,13,

30

600~900s

Prn.1,3,7,9,11

,12,13,30

900~1200s

Prn.1,3,7,9,11,

12,13,

30

1200~1500s

Prn.1,3,11,12,1

3,30

Doppler

caution flag

0~300s

Prn.1,3,7,9,1

1,12,13,

30

300~600s

Prn.1,3,7,9,11,1

2,13,

30

600~900s

Prn.1,3,7,9,11

,12,13,30

900~1200s

Prn.1,3,7,9,11,

12,13,

30

1200~1500s

Prn.1,3,11,12,1

3,30

Doppler

warning flag

0~300s

Prn.1,3,7,9,1

1,12,13,30

300~600s

Prn.1,3,7,9,11,1

2,13,

30

600~900s

Prn.1,3,7,9,11

,12,13,30

900~1200s

Prn.1,3,7,9,11,

12,13,

30

1200~1500s

Prn.1,3,11,12,1

3,30

TORNADO Case Study


AEROSONDE Flight Phases:

AEROSONDE Case Study

LEG 1 Climb 300 s

LEG 2 Turn Climb 300 s

LEG 3 Cruise 300 s

LEG 4 Level Turn 300 s

LEG 5 Turn Descent 300 s

LEG 6 Descent 300 s

51.4551.5

51.5551.6

51.6551.7

-0.65

-0.6

-0.55

-0.5

-0.45

0

500

1000

1500

2000

2500

3000

Longitude:Degree

Simulation Trajectory

Latitude:Degree

Altitu

de

:Me

ter

LEG 5

LEG 6

LEG 1

LEG 2

LEG 4 LEG 3

Alt

. (m

)

Lat (deg)

Long (deg)


Initial point of the A/C trajectory located at WGS coordinates: 51° 28′ 39″ N, 0° 27′ 41″ W (London)

GPS constellation simulated using the YUMA almanac data

Fly over the sea (free from man-made features)

GLS in the presence of LAAS was simulated

IFG Simulation

PITCH (deg) BANK (deg) THRUST (rpm)

CLIMB 15 0 7000

TURNING CLIMB 15 +10 7000

CRUISE 0 0 4000

LEVEL TURN 0 +45 6000

TURNING DESCENT -5 -40 2000

DESCENT -5 0 100

Dynamics Model

Settings


GPS receiver characteristics:

• Random vibration power curve is flat from 20Hz to 2000Hz with an amplitude of 0.005 g2/Hz

• Oscillator vibration sensitivity is 10-9 parts/g

• Third-order loop noise bandwidth is 18Hz

• The maximum LOS jerk dynamic stress is 10 g/s = 98 m/s3

The CIFs and WIFs relative to antenna masking, geometric accuracy degradations, C/N0, multipath and Doppler shift were generated

IFG Simulation


Long (deg)

Lat (deg)

Alt. (m)

Caution Flag (CIF)

Warning Flag (WIF)

IFG Simulation Results


IFG Output

CIF WIF

Climb --- ---

Turning Climb

334~374 s,

426~446 s

517~558 s

---

Cruise 874~900 s ---

Level Turn 901~1200 s

903~906 s, 913 s, 920~924 s, 930~931s,

938~942 s,948~949 s,956~959 s,

966~967 s,974~977 s, 984~985s,

992~995 s,1002~1003 s,1110~1113 s,

1020~1021 s1028~1031 s,1128~1129 s

1136~1139 s,1146~1147 s,1154~1157 s,

1164~1165 s,1172~1175 s,1182~1183 s,

1190~1192 s,1200 s

Turning Descent

1201~1441 s,

1448~1464 s,

1471~1487 s

1494~1500 s

1204 s,1223~1224 s,1247~1249 s,1272~1273 s

1296~1297 s,1320~1321 s,1344~1367 s,1368 s

1391~1392 s,1414~1415 s,1438~1439s,

1461~1462 s,1484~1485 s

Descent 1503~1800 s ---


FPM Simulation


FPM Architecture


Integrity Flags Analysis

Masking

PDOP

Multipath

Doppler

SNR

LAAS/WAAS

Key Point

The majority of accuracy and integrity degradations occur when the satellite elevation drops (body frame)


Integrity Flags Analysis Path Constraint

To avoid integrity degradations the new trajectory is defined in a way that avoids a drop of the available satellites elevation in body frame


A initial flight path is generated using the dynamic model

The Integrity Flag Generator (IFG) is run on that trajectory

The flight path optimization start at the first CIF

Pseudospectral Optimization Software (GPOPS ) is used to generate the new trajectory. The time is used as cost functional, the dynamic model as dynamic constraint, and the criterion on the elevation as path constraint

Boundary conditions are set from the value of the flight parameters at CIF time step

An alternate trajectory free of integrity degradation is then generated

This trajectory is run again through the IFG for validation

FPO Module Simulation


Aerosonde turning descent (Pitch = -5º, Bank = -40º)

CIF (2 sec predictive), followed by WIF (loss of GNSS)

Trajectory Optimization Results

Initial Trajectory With

CIF/WIF Corresponding Satellites

Elevation


New trajectory free of

integrity degradations

Corresponding Satellites

Elevation

The initial and final conditions for both trajectories are the same



CIF not followed by WIF

Pseudospectral methods produce quasi real-time solutions (acceptable for mission planning and some FMS implementations)

Additional and more efficient (real-time) algorithms are being tested



Simulation Results

The ABIA Integrity Flag Generator (IFG) is capable of generating integrity flags to provide both caution and warning signals when GNSS signals are degraded or lost

After the integrity caution flag is generated, the time available for the pilot/autopilot to react (before the integrity event is detected and the warning flag is generated), is at least 2 seconds

This TTC can support safety-critical tasks including GLS curved/segmented precision approach and automatic landing applications

The trajectory optimization problem was mathematically formulated and the real-time capability of the FPO module (using pseudospectral and other methods) was verified

In the dynamic conditions explored, data analysis showed that the ABIA system can provided useful integrity signals for CAT-III precision approach and automatic landing (automated and real-time FPO is essential in this case)


Investigate and compare different types of avionics sensor technologies and their potential to support the design of robust ABAS/ABIA architectures for manned A/C and UAS

Analyse the synergies between ABAS/ABIA and UAS Sense-and-Avoid (SAA)

Extend the ABAS/ABIA concepts to the Aeronautical Data Link (ADL) application domain

Study possible applications of the ABAS/ABIA concepts to advanced mission planning and forensic (accident investigation) applications

Evaluate the potential of ABAS/ABIA to enhance the performance of next generation avionics and CNS/ATM systems for Performance/Intent Based Operations (PBO/IBO) and Four-Dimensional Trajectory (4DT) management

Future Work


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References (2)


http://www.gmat.unsw.edu.au/snap/staff/omer_mubarak.htm

http://www.gmat.unsw.edu.au/snap/staff/omer_mubarak.htm

http://www2.hawaii.edu/~jmaurer/uav/



[23] R. Sabatini, T. Moore, C. Hill. “A New Avionics Based GNSS Integrity Augmentation System: Part 2 – Integrity

Flags.” The Journal of Navigation (in print). 2013.

[24] R. Sabatini, T. Moore and C. Hill. “A New Avionics Based GNSS Integrity Augmentation System: Part 1 -

Fundamentals.” The Journal of Navigation. First published online: 21 March 2013 (final journal print planned for

Vol. 66, No. 3, May 2013). DOI: 10.1017/S0373463313000027.

[25] R. Sabatini, C. Bartel, A. Kaharkar and T. Shaid. "Low-cost Vision Sensors and Integrated Systems for

Unmanned Aerial Vehicle Navigation and Guidance." ARPN Journal of Systems and Software, ISSN: 2222-

9833, Vol. 2, Issue 11, pp. 323-349. December 2012.

[26] R. Sabatini, L. Rodríguez, A. Kaharkar, C. Bartel and T. Shaid." Carrier-phase GNSS Attitude Determination and

Control System for Unmanned Aerial Vehicle Applications." ARPN Journal of Systems and Software, ISSN:

2222-9833, Vol. 2, Issue 11, pp. 297-322. December 2012.

[27] R. Sabatini, T. Moore and C. Hill. “A Novel Avionics-Based GNSS Integrity Augmentation System for UAS

Applications.” Paper presented at the Royal Institute of Navigation (RIN) Conference on Unmanned Air Vehicles

- Sharing the Airspace. Teddington (UK), February 2013.

[28] R. Sabatini, T. Moore and C. Hill. “Avionics Based GNSS Integrity Augmentation for Mission- and Safety-Critical

Applications.” Paper presented at 25th International Technical Meeting of the Satellite Division of the Institute of

Navigation: ION GNSS-2012. Nashville (Tennessee), September 2012.

[29] R. Sabatini, Y. Liu, K. De Ridder, A. Gardi, S. Ramasamy, D. Zammit-Mangion, L. Rodriguez. “ENDEAVOUR

Project – Novel Avionics and ATM Systems for SESAR and NextGen.” Paper presented at the Conference

Avionics Europe 2013 – Tackling the Challenges in Avionics: Single Sky Many Platforms. Munich (Germany),

February 2013.

[30] R. Sabatini, C. Bartel, A. Kaharkar, T. Shaid, D. Zammit-Mangion and H. Jia. “Vision Based Sensors and

Multisensor Systems for Unmanned Aerial Vehicles Navigation and Guidance.” Paper presented at the European

Navigation Conference 2012 (ENC 2012). Gdansk (Poland), April 2012.

References (3)


Questions & Discussion

Thank you for your attention!

Contact Information:

Assoc. Prof. Roberto Sabatini

Royal Melbourne Institute of Technology (RMIT) University

School of Aerospace, mechanical & Manufacturing Engineering

115 Queensberry Street, Carlton, VIC 3053 (Australia)

E: [email protected], T: +61 3 9925 8015 ; +61 457 126 495


Integrity Processing Layer

Data Extraction Layer

GNSS and Sensors Layer

GNSSAircraft

Sensors



Objects

Navigation and

Flight DynamicsGNSS

Constellation

Databases Avionics Data

Signal Analysis

Module

Doppler Analysis

Module

Obscuration


Module


mailto:[email protected]

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A Novel GNSS Avionics-Based Integrity Augmentation System