ESA UNCLASSIFIED - For Official Use

GNSS Raw Measurements experience from app competitions

2nd ESA Galileo App Competition 2018/2019

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 2

Applications

12 proposalsreceived 12 November 2018

8 selected to proceed to Step 2

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 3

Final Competition• Final event took place on 18/04/2019 at ESTEC

• 5 teams selected for the Final:

• GADIP3 by O’ThiSaVRoS

• Inari by Inari Team

• NavGate by Team GNSS Tonic

• Step with GNSS by Space Walkers Team

• POINTapp by University of Nottingham

• Prior to the Final the apps were extensively tested by ESA at ESTEC

• Results from the tests of the 5 apps have been compared with the results of

Google analysis app and ESA PPP s/w.

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 4

Competition Apps Outline

757+

GADIP3 NavGate Step with GNSS INARI PointApp

PPP & iono GeoReferencedmessages & AR

Gamification & Raw meas database

AGC & spoofing detection

Carrier Smoothing

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 5

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 6

… and the winners

1. GADIP3 by O’ThiSaVRoS

2. NavGate by Team GNSS Tonic

3. Step with GNSS by Space Walkers Team

• Innovation price of GSA

and Winner of Public Vote: Inari by Inari Team

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 7

GalileoPVT: ESA reference Android app

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 8

GalileoPVT - Augmented Reality View

GalileoPVT

Compatible with any phone with Android 7 (2500+ downloads)

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 9

Retrieval of Satellite and Clock Orbits

SLP – SUPL Location Platform (server)

http://www.ppp-wizard.net/caster.html

NTRIP CASTER(CNES, ESOC)

Broadcast real-time corrections for precise orbits and clock

SSL data connection

Android GnssNavigationMessageCallback

Broadcast ephemerids (near real-time)

Broadcast ephemerids (real-time)

Navigation message broadcast on L-Band

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 10

SUPL SSL server connection and Navigation Data view of the Galileo PVT app

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 11

Velocity computation

From https://www.onosokki.co.jp/English/hp_e/products/keisoku/automotive/lc8_principle.htm

Estimation based on:• satellites’

Doppler shifts or• time differenced

carrier phase

provided through Android API (PseudorangeRatemetersperSecond)

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 12

Doppler based Velocity estimation in Galileo PVT

Cruise control 80 km/h

Galileo PVT estimates~78 km/h

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 13

Loosely Coupled GNSS + INS

Correct inertial sensors

Attitude update

Gravity update

Velocity update

Position update

Measurement update

GNSSReceiver

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 14

Loosely Coupled GNSS + INS with and without INS calibration

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 15

Matlab Toolbox

• Common Log File for:

•Raw measurements (GNSSLogger format)

•GPS and Galileo Ephemerids (from SUPL & live broadcast)

•Ionospheric model parameters

•INS measurements (acceleration + gyro) log at 10 Hz

•Common time scale between INS and GNSS meas

• Post-processing tool for fast prototype of new GNSS algorithms

• Loosely Coupled EKF with GNSS + INS

• Converter from Raw measurements to RINEX (raw measurements

screening, pseudo-range ms ambiguity resolution, multi-frequency, half/quarter

cycle phase bias resolution)

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 16

Offline real-time PPP processing

GalileoPVTlog with Android

GNSS Raw Meas.

ESA RINEX Converter

MSP3PPP with ambiguity resolution

Broadcast Navigation Message

NTRIP Corrections

SP3, CLK, SINEX BIASFiles

Precise position

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 17

MSP3 and Android GNSS raw measurements

Inputs: CNES PPP Wizard

MSP3 (NSL) processing tool (result of ESA TRP act.):

• Multi-GNSS, multi freq

• PPP-like (fix ambig.) approach

• Sequential Extended Kalman Filter (EKF)

• uncombined observations

• iono-weighted model

• RAIM

• It can be fed with raw measurements coming either from professional RX +

prof. grade antenna or from the smartphone

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 18

Accuracy context during the pedestrian test…

Write the two words ESA and

Galileo on the football pitch

Level 1: ESA with a font

height of 15 m

Level 2: GALILEO with a

font height of 7 m

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 19

GNSS Analysis App @ g.co/gnsstools

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 20

GPS+Galileo, Raw PR and Carrier Smoothed PRFrom GNSS Analysis App

Dual frequency

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 21

GPS+Galileo, L1 only and L1/E1+L5/E5a (smooth)From GNSS Analysis App

Single Frequency Dual Frequency

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 22

GNSS is better with E5

E5a/L5 measurements

boost PVT performances!

PR smooth GPS+GAL

L1/L5

PR smooth GPS+GALL1 only

From GNSS Analysis App

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 23

Horizontal position error gain with second frequency(raw pr)

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 24

Results with MSP3 + GalileoPVT logs

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 25

MSP3 single vs dual frequency

GPS+GALL1 only

GPS+GALL1/L5

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 26

PPP with single and dual frequency measurements

HorizontalError [m]

MSP3 GAL+GPS E1/L1

MSP3 GAL+GPS E1/E5a+ L1/L5

Std. dev 1.82 m 0.89 m

50 % 3.01 m 1.80 m

68 % 3.78 m 2.44 m

95 % 6.19 m 3.85 m

Availability 98.6%

E5a/L5 measurements

boost PPP performance!

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 27

What’s in the near future?

New chips and smartphones with dual frequency GNSS (Xiaomi, Samsung,

Lenovo, Huawei)

Third frequency?

Better antennas?

Support to new constellations: BDS-3, NAVIC

Android apps with PPP (Gadip3, Galileo P3VT, …)

ESA UNCLASSIFIED - For Official Use Paolo Crosta | 26/06/2019 | Slide 28

Thank you!