GNSS devices: validations state of play, perspective …ies-webarchive-ext.jrc.it/mars/mars/content/download/2632/13387/...GNSS devices: validations state of play, perspective studies

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GNSS devices: validations state of play,

perspective studies

Cozmin LUCAU

GeoCAP, JRC Ispra

1. GNSS devices validated/certified• by member states (MS)

• by reference laboratories (RL)

• by NAVCERT

2. GNSS devices available for 2012 control campaign

3. Discussions• Use of GNSS devices validated by another MS ?

• Continuous and/or vertex ?

• Measurements in difficult conditions (forest) ?

4. Perspectives

Outline

2



• by NAVCERT





4. Perspectives

Outline

1. GNSS devices validated/certified

Member States (MS)- Statistical analysis carried out by MS (and verified by

JRC)- Statistical analysis carried out by JRC

Reference Laboratory (RL)

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1. GNSS devices validated/certified

Member States (MS)- Statistical analysis carried out by MS (and verified by

JRC)- Statistical analysis carried out by JRC

Reference Laboratory (RL)

NAVCERTthe certifying company commits its responsibility for any measurement done with a certified instrument



• by NAVCERT





4. Perspectives

Outline

4

1. GNSS devices validated - MS

http://marswiki.jrc.ec.europa.eu/wikicap/index.php/GNSS_receivers_validated#GNSS_devices_validated_by_Member_States

56 devices/modes/methods were validated since 2007 !!!

Number of validated GNSS devices per year

Ongoinganalyses

1. GNSS devices validated - MSFor 2 devices/modes/methods, the calculated R is too

high (> 1.5m) and can not be used for area measurement

Holux GM270 – standalone (FR)Magellan Mobile Mapper – standalone (LT)

* Only 2007-2011data : n = 53

Number of validated GNSS devices per tolerance class

5

1. GNSS devices validated - MSFor 34 devices /modes/methods out of 51 (67 %

from validated devices) the tolerance is lower than 0.75 m !!

* Only 2007-2011 data, with R<1.5m; n = 51


1. GNSS devices validated - MS32 devices/modes/methods out of 51 (63 % from

validated devices) uses differential corrections (EGNOS, DGPS real time or post-processing)

The use of differential corrections, increase the accuracy of

absolute position !!


Number of validated GNSS devices per measurement mode

6

1. GNSS devices validated - MSThe continuous measurement method is more frequently used: 33 devices out of 51 validates

(65%)


Continuous measurement method can

be faster BUT have to pay

attention when are

measuring the corners

!!Number of validated GNSS devices per measurement method



• by NAVCERT





4. Perspectives

Outline

7

1. GNSS devices validated - RL

http://marswiki.jrc.ec.europa.eu/wikicap/index.php/GNSS_receivers_validated#GNSS_devices_validated_by_Reference_Laboratories

21 devices /modes/methods validates since 2010

• Leica Geosystems AG, Heerbrugg, Switzerland

• Scientific Stanislaw Staszic Association, Cracow, Poland

• University of Warmia and Mazury, Olsztyn, Poland

Number of validated GNSS devices per year

1. GNSS devices validated - RLFor 1 device, the calculated R is too high (> 1.5m)

and can not be used for area measurements

ASUS P527 with GPS receiver Haicom HI-408 BT


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1. GNSS devices validated - RLFor 10 devices /modes/methods out of 20 (50%

from validated devices) the tolerance is lower than 0.75 m !!

* Only data with R<1.5m; n = 20


1. GNSS devices validated - RL12 devices /modes/methods out of 20 (60 % from

validated devices) uses differential corrections (EGNOS, DGPS real time or post-processing)


Number of validated GNSS devices per measurement mode

9

1. GNSS devices validated - RLThe continuous measurement method is more frequently used: 16 devices out of 20 validates

(80%)


Number of validated GNSS devices per measurement method



• by NAVCERT





4. Perspectives

Outline

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1. GNSS devices certified

http://www.tuev-sued.de/navcert/en/certification_marks/ppp_80010/references

4 devices /modes/methods have in present a valid certificate

• TOPCON GMS-2 (B class – 0,8m)• TOPCON GRS-1 (A class – 0,1m)• StarFire iTC (A class – 0,3m)• GEOmeterMX (B class – 0,5m)

For 7 devices the certificates are expired - legal issue (certificate valid if no technical change)

- no renewal from manufacturer - to check with NAVCERT !!!



• by NAVCERT





4. Perspectives

Outline

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Thank you for the questionnaire !!!

Your answers allow us to have an overall view about

the number of used device, the measurement

mode and method, the specific uses of the

receivers ………………….

and to try to clarify some points….


> 6200 receivers !!!!

The statistics calculated in the next slides of this presentation are preliminaries and take in account only partially data due to:- For the 1000 receivers used in Poland

there are not yet complete information

- Some data were filled yesterday evening and today impossible to update all graphics

- Some clarifications needed for specific cases

General trends are presented !!!

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3139 receivers /modes/methods out of 4833 (65 %from analyzed sample) uses differential corrections

(EGNOS, DGPS real time or post-processing)

Number of available GNSS receivers per measurement mode

Similar value with value calculated for all

validated/certified device: 47 out of 75 (63%)

Number of validated/certified GNSS devicesper measurement mode


3381 receivers /modes/methods out of 5126 (66 %from analyzed sample) are used in vertex AND

continuous method (“combined”)

The use of GNSS devices in both

measurement methods, vertex and continuous, seems to be used very often on the field !!!!

Number of available GNSS receivers per measurement method

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* the same receiver can be used for different applications

The majority of existing receivers are used for area measurements (n=5087*)

• During the Audit C.E.• Used for RD controls (2nd pillar)• Some Cross - compliance feature capture• Verification of good orthorectification for current year imagery used for RS• Other uses different measurements (location, orientation, ...etc)• LPIS QA rapid field visits. Point capture for photographs

Other applications

Number of available

GNSS receivers

per application

type


The majority of used receivers (n=3111) are validated by MS (69% from considered sample of 4494)

Number of available GNSS receivers validated - certified

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• by NAVCERT





4. Perspectives

Outline

3. DiscussionsUse of GNSS devices validated by a reference laboratory or another MS ……..

Leica Zeno 10Validated in Slovakia in 2011ContinuousR = 0,5

Leica Zeno 10Validated in Italy in 2011ContinuousR = 0,75 m

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Leica Zeno 10Validated in Slovakia in 2011ContinuousR = 0,5


0.5 m ???? 0.75 m ????

????Which R value to be eventually used, for another MS (PL for

example)

??????


0.5 m ???? 0.75 m ????

Leica Zeno 10Validated in Slovakia in 2011ContinuousR = 0,5with SKPOS correction in real time


No SKPOS in Poland !!!

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Leica Zeno 10Validated in Slovakia in 2011ContinuousR = 0,5 with SKPOS correction in real time

Leica Zeno 10Validated in Italy in 2011ContinuousR = 0,75 mwith EGNOS corrections

0.5 m ???? 0.75 m ????

EGNOS estimated error:

- 2.4 -3.5 m in Italy- 3.6 – 7.3 m in

Poland

No SKPOS in Poland !!!


0.5 m ???? 0.75 m ????

You can have an idea about the performances of this receiver

BUT …….

NEW VALIDATION NEDEED !!!!

Leica Zeno 10Validated in Slovakia in 2011ContinuousR = 0,5 with SKPOS correction in real time

Leica Zeno 10Validated in Italy in 2011ContinuousR = 0,75 mwith EGNOS corrections

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47 devices (modes/methods) from 75 validated/certified (MS+RL+NAVCERT) uses corrections (EGNOS, DGPS real time or post-processing) - 63%

We recommend to organize validation tests taking in account specific conditions for

each MS (region) !!!

????!!!!THE SAME- Software- Firmware- Settings- Measurement method- …….

Ex. GeoXT, continuous- FR – Arpent GIS v 4,7- PL – Terrasync v 2.53- LV – Terrasync v 2.31

Total number of validated/certified GNSS devicesper measurement mode

2 days with 3 operators + 1 day for organization/results



• by NAVCERT





4. Perspectives

Outline

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3. DiscussionsContinuous and/or vertex ?

The “combined” measurements (vertex + continuous) are very often used during on the field controls !!!!

Validated/certified devices(7 out of 75)

Survey preliminary result(29 out of 71)

3. DiscussionsContinuous and/or vertex ?

Survey preliminary result

Number of used devices (modes/methods)

Number of used receivers

The device have to be validated for the both

measurement methods, vertex and

continuous !!!!!

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3. DiscussionsContinuous and/or vertex ?For vertex measurement method, intermediary vertices measured

between corners, even if there are straight lines, are helpful ?

L = 300 m

* Scale not respected !!!!!

x* = 3 m due to border recognition

Real area (RA) = 90000 sqmReal perimeter = 1200 m

Ex. Only border interpretation error, without taking in account GNSS errors

Measured area ± 89360 sqm

R=1.0 m tolerance ± 1190 sqm

R=0.5 m tolerance ± 595 sqm

Between 2 and 4 minutes more needed to measure intermediates

vertices for this field !!!!!!

????????

Measured perimeter ±1190 m

Error = ± 640 sqm > 595 sqm

3. DiscussionsContinuous and/or vertex ? 1 sec/vertex

Ex. Only GNSS errors, without

taking in account border

interpretation error*.

* - depending of the field, the

border interpretation errors can

be more much higher than GNSS

errors

Temporal dependency

Standard deviation

Distance between vertices (m)

Five square fields- 100 m- 200 m- 300 m- 500 m- 1000 m

GeoXTstandalone GeoXT with

EGNOS corections

The impact of intermediate vertices f.

of parcel area, temporal dependency,

number of measurements/vertex

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3. DiscussionsContinuous and/or vertex ? 5 sec/vertexTemporal

dependency

Distance between vertices (m)

Five square fields- 100 m- 200 m- 300 m- 500 m- 1000 m

GeoXTstandalone GeoXT with

EGNOS corections

Ex. Only GNSS errors, without

taking in account border

interpretation error*.

* - depending of the field, the

border interpretation errors can

be more much higher than GNSS

errors

Standard deviation

The impact of intermediate vertices f.

of parcel area, temporal dependency,

number of measurements/vertex



• by NAVCERT





4. Perspectives

Outline

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3. DiscussionsMeasurements in difficult conditions (forest) ?

Number of used receivers

Measurements in

difficult conditions

(forest) ……..

(continuous/vertex,

UAV, laser, …. ??)

Linear feature

measurements …

(positioning of

the feature !!)

LPIS update …

(absolute

accuracy of GNSS

device !!)



• by NAVCERT





4. Perspectives

Outline

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4. Perspectives- > 6200 receivers !!!!

- validation/certification ongoing process: new receivers, complementary

methods (vertex AND continuous), improvement of EGNOS corrections

(coverage and accuracy), etc..

- due to the high quality of new GNSS receivers, the independent errors (use of

device, border interpretation) are higher

4. Perspectives- > 6000 receivers !!!!

- validation/certification ongoing process: new receivers, complementary

methods (vertex AND continuous), improvement of EGNOS corrections

(coverage and accuracy), etc..

- due to the high quality of new GNSS receivers, the independent errors (use of

device, border interpretation) are higher

- detailed and complete instructions for trained inspectors

- new studies concerning

- EGNOS impact

- measurements in forest

- …….

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Thank you for your attention!

Documents

GNSS devices: validations state of play, perspective …ies-webarchive-ext.jrc.it/mars/mars/content/download/2632/13387/...GNSS devices: validations state of play, perspective studies