Commission Delegated Regulation (EU) 2017/79Show full title

2. Test methods

2.1. Test conditions

2.1.1. The test object is the eCall, which includes a GNSS receiver and a GNSS antenna, specifying navigation characteristics and features of the tested system.

2.1.2. The number of the eCall test samples shall be at least 3 pieces and can be tested in parallel.

2.1.3. The eCall is provided for the test with the installed SIM-card, operation manual and the software (provided on electronic media).

2.1.4. The attached documents shall contain the following data:

• device serial number;

• hardware version;

• software version;

• device provider identification number;

• relevant technical documentation to perform the tests.

2.1.5. Tests are carried out in normal climatic conditions in accordance with standard ISO 16750-1:2006:

• air temperature 23 (± 5) °C;

• relative air humidity of 25 % to 75 %.

2.1.6. Tests of the eCall in respect of its GNSS receiver shall be performed with the test and auxiliary equipment specified in Table 1.

Table 1

Recommended list of measurement instruments, test and auxiliary equipment

Note: it is allowed to apply other similar types of equipment providing determination of characteristics with the required accuracy.
Equipment name	Required technical characteristics of test equipment
	Scale range	Scale accuracy
Global navigation satellite system simulator of Galileo and GPS signals	Number of simulated signals: at least 12	Mean square deviation of random accuracy component of pseudo-range to Galileo and GPS satellites not more than: stadiometric code phase: 0,1 metres; communication carrier phase: 0,001 metres; pseudovelocity: 0,005 metres/second.
Digital stopwatch	Maximum count volume: 9 hours 59 minutes 59,99 seconds	Daily variation at 25 (± 5) °С not more than 1,0 seconds. Time discreteness 0,01 seconds.
Vector network analyser	Frequency range: 300 kHz .. 4 000 kHz Dynamic range: (minus 85 .. 40) dB	Accuracy F = ± 1·10– 6 kHz Accuracy D = (0,1 .. 0,5) dB
Low-noise amplifier	Frequency range: 1 200 .. 1 700 MHz Noise coefficient: not more 2,0 dB Amplifier gain coefficient: 24 dB
Attenuator 1	Dynamic range: (0 .. 11) dB	Accuracy ± 0,5 dB
Attenuator 2	Dynamic range: (0 .. 110) dB	Accuracy ± 0,5 dB
Power source	Range of direct current voltage setting: from 0,1 to 30 volts	Accuracy V = ± 3 %
	Current intensity of output voltage: at least 3 amperes	Accuracy A = ± 1 %

2.1.7. Unless otherwise specified, GNSS signal simulation shall follow ‘Open sky’ pattern as shown in Figure 1.

Figure 1

Open sky definition

Zone	Elevation range (degrees)	Azimuth range (degrees)
A	0 – 5	0 – 360
Background	Area out of Zone A

2.1.8. Open Sky plot — Attenuation:

	0 dB
A	– 100 dB or signal is switched off

2.2. Test procedures

2.2.1. NMEA-0183 messages output test.

2.2.1.1. Make connections according to Figure 2.

Figure 2

Diagram of test stand

2.2.1.2. Prepare and turn on the eCall. By means of operation manual and developer software, set up the GNSS receiver for receiving signals from Galileo, GPS and SBAS. Set up the GNSS receiver to output NMEA-0183 messages (messages RMC, GGA, VTG, GSA and GSV).

2.2.1.3. Set up the simulator according to the simulator user guide. Initialize simulator script with the parameters, given in Table 2 for Galileo, GPS and SBAS signals.

Table 2

Main parameters of simulation script for static scenario

Simulated parameter	Value
Test duration, hh:mm:ss	01:00:00
Output frequency	1 hertz
eCall location	Any specified land point between latitude range 80°N and 80°S in coordinate system WGS-84
Troposphere:	Standard predefined model by the GNSS simulator
Ionosphere:	Standard predefined model by the GNSS simulator
PDOP value in the test interval	2,0 ≤ PDOP ≤ 2,5
Simulated signals	Galileo (E1 frequency band OS); GPS (L1 frequency band C/A code); combined Galileo/GPS/SBAS.
Signal strength:
— GNSS Galileo;	minus 135 dBm;
— GNSS GPS.	minus 138,5 dBm.
Number of simulated satellites:	at least 6 Galileo satellites; at least 6 GPS satellites; at least 2 SBAS satellites

2.2.1.4. By means of corresponding serial interface, set the connection between the eCall and PC. Control the possibility of receiving navigation information via NMEA-0183 protocol. The value of field 6 in the GGA messages is set to ‘2’.

2.2.1.5. Test results are considered successful if navigation information via NMEA-0183 protocol is received in all the eCall samples.

2.2.1.6. The test of NMEA-0183 messages output and the assessment of the positioning accuracy in autonomous static mode can be combined.

2.2.2. Assessment of positioning accuracy in autonomous static mode.

2.2.2.1. Make connections according to Figure 2.

2.2.2.2. Prepare and turn on the eCall. By means of developer software, make sure that the GNSS receiver is set up for receiving Galileo, GPS and SBAS combined signals. Set up the GNSS receiver to output messages according to the NMEA-0183 protocol (GGA, RMC, VTG, GSA and GSV messages).

2.2.2.3. Set up the simulator in accordance with its operational manual. Start simulation of combined Galileo, GPS and SBAS signals script with the set parameters given in Table 2.

2.2.2.4. Set up the recording of NMEA-0183 messages after receiving the navigation solution. Up to the moment the simulation script is complete, the NMEA-0183 messages are output by the GNSS receiver to a file.

2.2.2.5. Upon receiving the navigation solution set up recording of NMEA-0183 messages output by the GNSS receiver to a file, up to the moment the simulation script is complete.

2.2.2.6. Extract coordinates: latitude (B) and longitude (L) contained in GGA (RMC) messages.

2.2.2.7. Calculate the systematic inaccuracy of coordinate's determination on stationary intervals according to formulas (1), (2), for example for latitude coordinate (B):

(1)	ΔB(j) = B(j) – Btruej ,
(2)	,

• B_truej is the actual value of B coordinate in j time moment, in arc-seconds.

• B(j) is the determined value of B coordinate in j time moment by the GNSS receiver, in arc-seconds.

• N is the amount of GGA (RMC) messages, received during the test of GNSS receiver.

2.2.2.8. Similarly calculate the systematic inaccuracy of L (longitude) coordinate.

2.2.2.9. Calculate standard deviation (SD) value according to formula (3) for B coordinate:

(3)

,

2.2.2.10. Similarly calculate the SD value for L (longitude) coordinate.

2.2.2.11. Convert calculated coordinates and SD values of latitude and longitude determination from arc-seconds to meters according to formulas (4) – (5).

2.2.2.12. For latitude:

(4-1)	,
(4-2)	,

2.2.2.13. For longitude:

(5-1)	,
(5-2)	,

— а

—

Semi-major axis of ellipsoid, metres

— e

—

first eccentricity, [0 – 1]

— φ

—

determined value of latitude, radians.

2.2.2.14. Calculate horizontal position error according to formula (6):

(6)

,

2.2.2.15. Repeat test procedures according to 2.2.2.3 – 2.2.2.14 for GNSS Galileo signals with simulation parameters, given in Table 2.

2.2.2.16. Repeat test procedures according to 2.2.2.3 – 2.2.2.14 only for GPS GNSS signals with simulation parameters, given in Table 2.

2.2.2.17. Repeat test procedures according to 2.2.2.3 – 2.2.2.16 with other eCall samples, provided for the test.

2.2.2.18. Determine average values according to (6) obtained for all tested eCall samples.

2.2.2.19. Tests results are considered satisfactory if horizontal position errors as defined by formula (6) obtained with all eCall samples do not exceed 15 metres under open sky conditions at confidence level 0,95 probability for all simulation scripts.

2.2.3. Assessment of positioning accuracy in autonomous dynamic mode.

2.2.3.1. Repeat test procedures described in section 2.2.2, but 2.2.2.15 – 2.2.2.16 with simulation script for manoeuvring movement, given in Table 3.

Table 3

Main parameters of simulation script for manoeuvring movement

Simulated parameter	Value
Test duration, hh:mm:ss	01:00:00
Output frequency	1 hertz
eCall location	Any specified land point between latitude range 80°N and 80°S in coordinate system WGS-84
Model of movement:	Manoeuvring movement
— speed, km/h;	140
— turning radius, metres;	500
— turning acceleration, metres/second2.	0,2
Troposphere:	Standard predefined model by the GNSS simulator
Ionosphere:	Standard predefined model by the GNSS simulator
PDOP value in the test time interval	2,0 ≤ PDOP ≤ 2,5
Simulated signals	Combined Galileo/GPS/SBAS
Signal strength:
— GNSS Galileo;	minus 135 dBm;
— GNSS GPS.	minus 138,5 dBm.
Number of simulated satellites:	at least 6 Galileo satellites; at least 6 GPS satellites; at least 2 SBAS satellites

2.2.3.2. Determine average values according to (6) obtained for all tested eCall samples.

2.2.3.3. Tests results are considered satisfactory if horizontal position errors obtained with all eCall samples do not exceed 15 metres under open sky conditions at confidence level 0,95 probability.

2.2.4. Movement in shadow areas, areas of intermittent reception of navigation signals and urban canyons.

2.2.4.1. Repeat test procedures described in section 2.2.3 for simulation script for movement in shadow areas and areas of intermittent reception of navigation signals (given in Table 4) with an urban canyon signal pattern described in Figure 3.

Table 4

Main parameters of movement in shadow areas and areas of intermittent reception of navigation signals

Simulated parameter	Value
Test duration, hh:mm:ss	01:00:00
Output frequency	1 hertz
eCall location	Any specified land point between latitude range 80°N and 80°S in coordinate system WGS-84
Model of movement:	Manoeuvring movement
— speed, km/h;	140
— turning radius, metres;	500
— turning acceleration, metres/second2.	0,2
Satellite visibility:
— signal visibility intervals, seconds;	300
— signal absence intervals, seconds.	600
Troposphere:	Standard predefined model by the GNSS simulator
Ionosphere:	Standard predefined model by the GNSS simulator
PDOP value in the test time interval	3,5 ≤ PDOP ≤ 4,0
Simulated signals	Combined Galileo/GPS/SBAS
Signal strength:
— GNSS Galileo;	minus 135 dBm;
— GNSS GPS.	minus 138,5 dBm.
Number of simulated satellites:	at least 6 Galileo satellites; at least 6 GPS satellites; at least 2 SBAS satellites

Figure 3

Urban canyon definition

Zone	Elevation range (degrees)	Azimuth range (degrees)
A	0 – 5	0 – 360
B	5 – 30	210 – 330
C	5 – 30	30 – 150
Background	Area out of Zone A, B, C

2.2.4.2. Urban canyon plot- Attenuation:

	0 dB
B	– 40 dB
C	– 40 dB
A	– 100 dB or signal is switched off

2.2.4.3. Tests results are considered satisfactory if horizontal position errors obtained with all eCall samples do not exceed 40 metres in urban canyon conditions at confidence level 0,95 probability.

2.2.5. Cold start time to first fix test.

2.2.5.1. Prepare and turn on the eCall. By means of developer software, make sure that GNSS module is set to receive Galileo and GPS signals.

2.2.5.2. Delete all position, velocity, time, almanac and ephemeris data from the GNSS receiver.

2.2.5.3. Set up the simulator according to the simulator user guide. Initialize simulator script with the parameters, given in Table 2 for Galileo and GPS signals with signal level minus 130 dBm.

2.2.5.4. By means of a stopwatch, measure time interval between signal simulation start and the first navigation solution result.

2.2.5.5. Conduct test procedures according to 2.2.5.2 – 2.2.5.4 at least 10 times.

2.2.5.6. Calculate average time to first fix in cold start mode based on measurements for all eCall samples, provided for the test.

2.2.5.7. The test result is considered to be positive, if average values of time to first fix calculated as described in 2.2.5.6, do not exceed 60 seconds for signal level down to minus 130 dBm for all the simulated signals.

2.2.5.8. Repeat test procedure according to 2.2.5.1 – 2.2.5.5 with signal level minus 140 dBm.

2.2.5.9. The test result according to 2.2.5.8 is considered to be positive, if average values of time to first fix, calculated as described in 2.2.5.6 do not exceed 300 seconds for signal level down to minus 140 dBm for all the simulated signals.

2.2.6. Test of re-acquisition time of tracking signals after block out of 60 seconds.

2.2.6.1. Prepare and turn on the eCall according to operational manual. By means of the developer software, make sure that GNSS receiver is set up to receive Galileo and GPS signals.

2.2.6.2. Set up the simulator according to the simulator user guide. Initialize simulator script with the parameters, given in Table 2 for Galileo and GPS signals with signal level minus 130 dBm.

2.2.6.3. Wait for 15 minutes and make sure the GNSS receiver has calculated eCall position.

2.2.6.4. Disconnect the GNSS antenna cable from the eCall and connect it again after time interval of 60 seconds. By means of stopwatch, determine time interval between cable connection moment and restoration of satellites tracking and calculation of the navigation solution.

2.2.6.5. Repeat test procedure according to 2.2.6.4 at least 10 times.

2.2.6.6. Calculate average value of re-acquisition time of satellite tracking signals by the eCall for all performed measurements and all eCall samples provided for the test.

2.2.6.7. The test result is considered to be positive, if average values of re-acquisition time after block out of 60 seconds measured as described in 2.2.6.6, do not exceed 20 seconds.

2.2.7. Test of GNSS receiver sensitivity in cold start mode, tracking mode, and re-acquisition scenario.

2.2.7.1. Turn on the vector network analyser. Calibrate the vector network analyser according to its operational manual.

2.2.7.2. Set up the diagram according to Figure 4.

Figure 4

Diagram of path calibration

2.2.7.3. Set zero signal path attenuation on attenuators. Measure the frequency response for a given signal path in the E1/L1 band of Galileo/GPS, respectively. Record the average path transmission factor in [dB] in this frequency band.

2.2.7.4. Assemble the circuit shown in Figure 5.

Figure 5

Arrangement for evaluation of GNSS module sensitivity

2.2.7.5. Prepare and turn on eCall according to operational manual. By means of developer software make sure that GNSS receiver is set to receive Galileo and GPS signals. Clear the GNSS receiver RAM such that the ‘cold’ start mode of the GNSS receiver of the eCall is achieved. Check that the position, velocity and time information is reset.

2.2.7.6. Prepare GNSS signals simulator according to its operation manual. Start Galileo and GPS signals simulation script, with parameters given in Table 2. Set output power level of the simulator to minus 144 dBm.

2.2.7.7. By means of a stopwatch, measure time interval between signal simulation start and the first navigation solution result.

2.2.7.8. Set the signal path attenuation on attenuators such that the signal on eCall antenna input is equal to minus 155 dBm.

2.2.7.9. By means of a stopwatch, verify that the eCall still provides navigation solution for at least 600 seconds.

2.2.7.10. Set the signal path attenuation on attenuators such that the signal on eCall antenna input is equal to minus 150 dBm.

2.2.7.11. Disconnect the GNSS antenna cable from the eCall and connect it again after time interval of 20 seconds.

2.2.7.12. By means of stopwatch, determine time interval between cable connection moment and restoration of satellites tracking and calculation of the navigation solution.

2.2.7.13. The test result is considered to be positive in case:

• the value of time to first fix in ‘cold’ start mode, as measured in 2.2.7.7, do not exceed 3 600 seconds at signal level on the antenna input of the eCall of minus 144 dBm in all the eCall samples;

• the GNSS navigation solution is available for at least 600 seconds at signal level on the antenna input of the eCall of minus 155 dBm as measured in 2.2.7.9 in all the eCall samples;

• and re-acquisition of GNSS signals and calculation of the navigation solution at signal level on the antenna input of the eCall of minus 150 dBm is possible and time interval measured in 2.2.7.12 does not exceed 60 seconds in all the eCall samples.