Multi-Receiver Vector Tracking

Transcription

1 Multi-Receiver Vector Tracking Yuting Ng and Grace Xingxin Gao please feel free to view the.pptx version for the speaker notes

2 Cutting-Edge Applications UAV formation flight remote sensing interference mitigation Network Sync. PMU time voltage/ current Sampling Device synchronized phasor measurements SAR-GNSS Processing 1

3 State-of-the-Art Techniques increased availability EKF VDLL VFLL IMU beamstearing Signal tracking clock Multiple antennas External aiding increased robustness RTK PPP DGPS Multiple receivers 2

4 State-of-the-Art Techniques increased availability EKF VDLL VFLL IMU beamstearing Signal tracking clock Multiple antennas External aiding increased robustness RTK PPP DGPS Multiple receivers 2

5 State-of-the-Art Techniques increased availability EKF VDLL VFLL IMU beamstearing Signal tracking clock Multiple antennas External aiding increased robustness RTK PPP DGPS Multiple receivers Cooperative Navigation Joint Signal Tracking 2

6 Multi-Receiver Vector Tracking Joint tracking of multiple GNSS receivers for increased accuracy, robustness and reliability 3

7 Outline Motivation Coop Nav, Joint Signal Tracking Our Approach Multi-Receiver Vector Tracking Implementation Hardware, Python SDR Experimental Validation Summary

8 MRVT Receiver Architecture incoming raw signal Channel 1... Receiver Channel N Receiver Receiver Network Scheme Scalar SRVT MRVT Entities N x M Channels M Receivers 1 Network Unknowns N x M x 4 M x 8 1 x 14 N Channels M Receivers 4 Unknowns M Receivers 8 Unknowns 1 Network 14 Unknowns 4

9 Comparison with other GNSS Processing Implementations Antenna array Differential GPS (DGPS) GNSS Receiver measurements / coordinates Nav Filter GNSS Receiver GNSS Receiver Single-Receiver Vector Tracking (SRVT) Multi-Receiver Vector Tracking (MRVT) 5

10 MRVT Block Diagram 6

11 MRVT Block Diagram 6

12 Single Receiver Vector Tracking Loop EKF-based Filter Vector Delay Lock Loop - James J. Spilker, Jr. Global Positioning System-Theory and Applications, Volumes I, II. AIAA, Washington, DC.,

13 Single Receiver PIA Vector Tracking State Representation Process Noise Cov. 8

14 Single Receiver PIA Vector Tracking State Representation Process Noise Covariance Matrix σ 2 σ 2 9

15 MRVT Block Diagram 10

16 MRVT Loop 11

17 MRVT Variations MRVT Enforce baseline, attitude and velocity constraints Enforce timing constraints MRPIAVT Enforce timing constraints clock bias differ by constant clock drift same 12

18 Multi-Receiver Vector Tracking Receiver Network Channel Receiver LOS Projections Code and Carrier NCO EKF incoming GPS signal Correlator Code and Carrier Discriminators Time Update Measurement Update MRVT Filter navigation solution a priori information 13

19 Outline Motivation Coop Nav, Joint Signal Tracking Our Approach Multi-Receiver Vector Tracking Implementation Hardware, Python SDR Experimental Validation Summary

20 Overall Implementation GNSS antennas ADCs Network Receiver Hardware Software (Python SDR) 4.60m 14

21 Python SDR : Research Platform Share information effectively SDR (Software Defined Radio) OOP (Object-Oriented Programming) 15

22 Python SDR : Research Platform 16

23 Python SDR : Teaching Platform 17

24 Python SDR : Teaching Platform 17

25 Outline Motivation Coop Nav, Joint Signal Tracking Our Approach Multi-Receiver Vector Tracking Implementation Hardware, Python SDR Experimental Validation Summary

26 MRVT Positioning Results SRVT MRVT SRVT zoomed in MRVT zoomed in 18

27 MRVT Positioning Results SRVT MRVT SRVT zoomed in MRVT zoomed in 18

28 MRVT Results: Reliable Altitudes 19

29 MRVT Results: Accurate Baselines 19

30 MRVT Results: Less Noisy Speeds 19

31 Results with Buildings+Accelerations SRVT MRVT 20

32 Results with Buildings+Accelerations SRVT zoomed in MRVT zoomed in 20

33 MRPIAVT Results: Improved Timing Accuracy SRVT MRPIAVT 21

34 MRPIAVT Results: Improved Timing Accuracy SRVT MRPIAVT 21

35 MRPIAVT: Resistant to Jamming Added noise of different levels Clock bias comparison across different noise power Clock drift comparison across different noise power 22

36 MRPIAVT: Robust to Meaconing weak meaconing (1:1 power ratio) clock bias clock drift state error cov robust to attack strong meaconing (100:1 power ratio) clock bias clock drift state error cov attack detected 23

37 MRPIAVT: Detects Data Spoofing Attacked af 0 in Subframe 1 of Ephemerides satellite clock biases shifted by 4s clock bias clock drift state error cov attack detected 24

38 Outline Motivation Coop Nav, Joint Signal Tracking Our Approach Multi-Receiver Vector Tracking Implementation Hardware, Python SDR Experimental Validation Summary

39 Summary Proposed Multi-Receiver Vector Tracking (MRVT) Cooperative navigation Joint signal tracking Designed MRVT Architecture Implemented in Python SDR Conducted MRVT Experiments Validated Performance Improvements MRVT : Demonstrated increased accuracy in horizontal heading, altitudes, baselines, speeds, timing MRPIAVT : Demonstrated improved timing accuracy and precision, robustness against timing attacks 25

40 From all of Thank you!