Field experience with future GNSS ranging signals (a review). A.Simsky, J.-M. Sleewaegen, W. De Wilde Septentrio, Belgium

Transcription

1 Field experience with future GNSS ranging signals (a review). A.Simsky, J.-M. Sleewaegen, W. De Wilde Septentrio, Belgium Technical University of Munich June

2 Contents Septentrio: company profile Future: GPS + GLONASS + Galileo + Compass Summary table of new signals Experimental satellites: GIOVE-A/B, Compass-M1 Multipath performance of new signals BOC, MBOC, AltBOC L5 signal of SVN 49 June 8,

3 Septentrio: production + research 2000: Founded in Leuven, Belgium 2007: Gaselle prize, highest growth rate in Beligium Production Multifrequency GPS/GLONASS/Galileo receivers Mostly OEM-cards (RTK, surveying, machine control) GETR: scientific receivers for GIOVE-A/B Contract with ESA: Galileo TUR (Test User Receiver) Attention to GUI and support issues Attitude determination single-board systems Research Receivers for all the new signals Study the characteristics of new signals Multipath mitigation Use of multi-frequency signals in RTK GPS/INS integration Long baseline RTK June 8,

4 Frequency plan of GNSS signals June 8,

5 Spectra of GNSS signals June 8,

6 Table of all signals, noise high->low modulation GPS GLONASS Galileo Compass Eff. chip length, m Noise σ, m BPSK(0.5) L1-CA L2-CA BPSK (1) L1-CA L2C BOC(1,1) L1-BC (>150) 0.9 BPSK(2) E1, E5B MBOC L1-MBOC (B1-BOC) (< 150) 0.7 BPSK(5) P1, P2 E6BC BPSK(10) P1, P2, L E5a, E5b E BOC(10.5,1) (M-code) E6A (B2-BOC) (30) 0.5 BOC (15.5,1) (M-code) L1A (B2-BOC) (30) 0.4 AltBOC E5AltBOC? (10) 0.25 June 8,

7 Galileo signals GIOVE A: L1 + E5a + E5b or L1 + E6; GIOVE-B: L1 + E5a + E5b + E6 GIOVE-B: 2 options for L1BC: BOC(1,1) and MBOC June 8,

8 Multipath (theory) June 8,

9 Experimental Galileo satellites: GIOVE A/B GIOVE-A (launched ) GSTB-V2 / A GSTB-V2 / B L1+E5ab or L1+E6 GIOVE-B (launched ) L1(BOC(1,1) or MBOC) + E5ab + (E6) Lift-off mass 600 kg Power demand 700 W Stowed Dimensions: 1.3 m x 1.8 m x 1.65 m Lift-off mass 495 kg Power demand 760 W Stowed Dimensions: 1.0 m x 1.0 m x 2.4 m Receivers: GPS + Galileo/GIOVE : Аntenna Space Engineering GETR, AsteRx1, Asterx2/PolaRx3G 9

10 Multipath noise, Galileo signal Leuven -1 Leuven -2 La Plata Wuhan (6 days) (2 days) (5 days) (4 days) > 10º < 10º > 10º < 10º > 10º < 10º > 10º < 10º L1BC E5a E5b E6BC E6A L1A E5AltBOC June 8,

11 Multipath noise of Galileo, Leuven 2006 June 8,

12 Multipath noise of Galileo, La-Plata 2007 June 8,

13 Multipath noise E5 Alt-BOC June 8,

14 Multipath noise of Galileo, Leuven June 8,

15 Multipath noise of Galileo, Leuven June 8,

16 Multipath noise of Galileo, car test June 8,

17 Multipath noise of Galileo, car test Signal Rural Urban Static Movement Static Movement GPS-CA L1BC E5a E5b E6BC E5AltBOC June 8,

18 BOC(1,1) vs MBOC (theory) MBOC = 0.9*BOC(1,1)+0.1*BOC(6,1) Two options of MBOC: CBOC and TMBOC CBOC = BOC(1,1) + BOC(6,1) (superposition) CBOC shall be used for Galileo L1BC TMBOC shall be used for GPS L1C MBOC has one correlation peak June 8,

19 BOC(1,1) vs MBOC (results) M i = P i Φ i + 2λ 2 i Φ λ j 2 j Φ λ 2 i i June 8,

20 Comparison of two Galileo antennas Red: Space Engineering, Galileo Ground Segment Reference wideband, helicoidal Blue: geodetic-grade choke-ring antenna for reference stations L1BC multipath E5a multipath June 8,

21 Glonass signals Band: L1 L2 Code CA P CA P Old GLONASS modulation BPSK(0.5) BPSK(5) Nav. Message Bits/sec No signal BPSK(5) no data Frame, sec GLONASS- M (22 sats) modulation BPSK(0.5) BPSK(5) BPSK(0.5) BPSK(5) Nav. Message Bits/sec Frame, sec June 8,

22 ВPSK(5): Galileo Е6ВС vs GLONASS L2-Р June 8,

23 Compass: what is known Open Service: B1, B1-C, B2, B2a/b Authorized Service: B3, B3-A Phase II: 2012 (B1, B2, B3, regional) Phase III: 2020 (B1-C, B2a/b, B3-(A), global) 27 MEO, 3 IGSO, 5 GEO 4 satellites already launched 1 MEO, 3 GEO Constellation: 3 orbital planes, inclination 55 deg, alt UTC Signals decoded: CNES+UoStanford First receiver: Septentrio, (W. De Wilde et al, Inside GNSS, July/August 2007) June 8,

24 Complete table of Compass signals June 8,

25 Signals of the Compass M1 satellite Band (literature) E2 E5B (E6) GPS-L1CA Band (P. R. China) B1-I B2-I B Frequency, Mhz Modulation BPSK(2) BPSK(2) BPSK(10) BPSK(1) Code rate, bit/sec Code length 2046=1ms 2046=1ms 10230=1ms 1023=1ms Characteristics of the navigation message Frequency, bit/sec Frame 30 sec 30 sec??? 30 sec Sub-frame 6 sec 6 sec??? 6 sec Period 12 min 12 min??? 12.5 min June 8,

26 Compass multipath June 8,

27 Compass multipath - time series June 8,

28 Compass-M1 Problem Spikes on Carrier Frequency Detected April 2010 by Septentrio & DLR B1 & B2 2-3 AsteRx3 receiver June 8,

29 GPS L5 (PolaRx 3G L1/L5) June 8,

30 GPS L5 multipath (PolaRx 3G L1/L5) June 8,

31 FAQs BOC vs BPSK Wide band E5AltBOC signal Role of multipath noise, new signals More signals or more satellites? Future receivers: all signals or minimum?? June 8,

32 Thank you for your attention! website: June 8, 2010 Septentrio 32 COMMERCIAL IN CONFIDENCE