Resolution
MSC.233(82)
ADOPTION OF THE PERFORMANCE STANDARDS FOR SHIPBORNE GALILEO RECEIVER EQUIPMENT
(adopted on 5 December 2006)
THE
MARITIME SAFETY COMMITTEE,
RECALLING
Article 28(b) of the Convention on the International Maritime Organization concerning
the functions of the Committee,
RECALLING
ALSO resolution A.886(21), by which the Assembly resolved that the function of
adopting performance standards and technical specifications, as well as
amendments thereto shall be performed by the Maritime Safety Committee and/or
the Marine Environment Protection Committee, as appropriate, on behalf of the
Organization,
RECALLING
FURTHER that, in accordance with resolution A.815(19) by which the Assembly
adopted the IMO policy for the recognition and acceptance of suitable
radionavigation systems intended for international use to provide ships with
navigational position-fixing throughout their voyages, the GALILEO satellite
system may be recognized as a possible component of the world-wide
radionavigation system,
NOTING
that shipborne receiving equipment for the world-wide radionavigation system
should be designed to satisfy the detailed requirements of the particular
system concerned,
RECOGNIZING
the need to develop performance standards for shipborne GALILEO receiver
equipment in order to ensure the operational reliability of such equipment and
taking into account the technological progress and experience gained,
HAVING
CONSIDERED the recommendation made by the Sub-Committee on Safety of
Navigation, at its fifty-second session,
1.
ADOPTS the Performance standards for Shipborne GALILEO receiver equipment, set
out in the Annex to the present resolution;
2.
RECOMMENDS Governments ensure that GALILEO receiver equipment installed on or
after 1 January 2009 conform to performance standards not inferior to those
specified in the Annex to the present resolution.
Annex.
PERFORMANCE STANDARDS FOR SHIPBORNE GALILEO RECEIVER EQUIPMENT
1.1
Galileo is the European satellite navigation system. Galileo is designed as a
wholly civil system, operated under public control. Galileo comprises 30 medium
earth orbit (MEO) satellites in 3 circular orbits. Each orbit has an
inclination of 56°and contains 9 operational satellites plus one operational
spare. This geometry ensures that a minimum of 6 satellites are in view to
users world-wide with a position dilution of precision (PDOP) ≤ 3.5.
1.2
Galileo transmits 10 navigation signals and 1 search and rescue (SAR) signal.
The SAR signal is broadcast in one of the frequency bands reserved for the
emergency services (1544-1545 MHz) whereas the 10 navigation signals are
provided in the radio-navigation satellite service (RNSS) allocated bands:
4 signals occupy
the frequency range 1164-1215 MHz (E5a-E5b).
3 signals occupy
the frequency range 1260-1300 MHz (E6).
3 signals occupy
the frequency range 1559-1591 MHz (E2, L1, E1).
Each
frequency carries two signals; the first is a tracking signal – the so-called
pilot signal – that contains no data but increases the tracking robustness at
the receiver whereas the other carries a navigation data message.
Galileo
provides two different services of use for the maritime community.
1.3
The Galileo Open Service provides positioning, navigation and timing services,
free of direct user charges. The Open Service can be used on one (L1), two (L1
and E5a or L1 and E5b) or three (L1, E5a and E5b) frequencies.
1.4
The Galileo Safety of Life Service can be used on one (L1 or E5b) or two (L1
and E5b) frequencies1. Each of the L1 and E5b frequencies carries a
navigation data message that includes integrity information. The E5a frequency
does not include integrity data.
1.5
Galileo receiver equipment intended for navigation purposes on ships of speeds
not exceeding 70 knots, in addition to the general requirements specified in
resolution A.694(17)2, should comply with the following minimum
performance requirements.
______________
1 The integrity parameters
broadcast by the Galileo Safety of Life service will be unencrypted and
therefore fully accessible. Service Guarantees and Authentication services can
be made available, at a charge, through contractual means if desired.
2 Refer to publication IEC
60945.
1.6
These standards cover the basic requirements of position fixing, determination
of course over ground (COG), speed over ground (SOG) and timing, either for
navigation purposes or as input to other functions. The standards do not cover
the other computational facilities which may be in the equipment nor cover the
requirements for any other systems that may take input from the Galileo
receiver.
2.1
The words "Galileo receiver equipment" as used in these performance
standards include all the components and units necessary for the system
properly to perform its intended functions. The Galileo receiver equipment
should include the following minimum facilities:
.1 antenna
capable of receiving Galileo signals;
.2 Galileo
receiver and processor;
.3 means of
accessing the computed latitude/longitude position;
.4 data control
and interface; and
.5 position
display and, if required, other forms of output.
Note:
If Galileo forms
part of an approved Integrated Navigation System, requirements of 2.1.3, 2.1.4,
2.1.5 may be provided within the INS.
2.2
The antenna design should be suitable for fitting at a position on the ship
which ensures a clear view of the satellite constellation, taking into
consideration any obstructions that might exist on the ship.
3. PERFORMANCE
STANDARDS FOR GALILEO RECEIVER EQUIPMENT
The
Galileo receiver equipment should:
.1 be capable of
receiving and processing the Galileo positioning and velocity, and timing
signals on:
i) for a single
frequency receiver, the L1 frequency alone. The receiver should use the
ionospheric model broadcast to the receiver by the constellation to generate
ionospheric corrections;
ii) for a dual
frequency receiver, either the L1 and E5b frequencies or the L1 and E5a
frequencies. The receiver should use dual frequency processing to generate
ionospheric corrections;
.2 provide
position information in latitude and longitude in degrees, minutes and
thousandths of minutes3;
_______________
3 Galileo uses Galileo
Terrestrial Frame System (GTRF) datum which is a realization of the
International Terrestrial Frame Reference (ITRF) system and differs from WGS 84
by less than 5 cm worldwide.
.3 provide time
referenced to universal time coordinated UTC (BIPM)*;
________________
* Bureau International des
poids et measures.
.4 be provided
with at least two outputs from which position information, UTC, course over
ground (COG), speed over ground (SOG) and alarms can be supplied to other equipment.
The output of position information should be based on the WGS84 datum and
should be in accordance with international standards4. The output of
UTC, course over ground (COG), speed over ground (SOG) and alarms should be
consistent with the requirements of 3.16 and 3.18;
.5 have static
accuracy such that the position of the antenna is determined to within:
i) 15 m
horizontal (95%) and 35 m vertical (95%) for single frequency operations on the
L1 frequency;
ii) 10 m
horizontal (95%) and 10 m vertical (95%) for dual frequency operations on L1
and E5a or L1 and E5b frequencies5;
.6 have dynamic
accuracy equivalent to the static accuracy specified in .5 above under the sea
states and motion experienced in ships6;
______________
4 Publication IEC 61162.
5 The minimum accuracy
requirements specified for dual frequency processing are based on the
performance requirements established by the Organization in resolution
A.915(22) and resolution A.953(23) for navigation in harbour entrances, harbour
approaches and coastal waters.
The Galileo satellite
navigation system will be able to provide better accuracy (4 m horizontal 95%
and 8 m vertical 95%).
6 Refer to resolution
A.694(17), publications IEC 6721-3-6 and IEC 60945.
.7 have position
resolution equal or better than 0.001 minutes of latitude and longitude;
.8 have timing
accuracy such that time is determined within 50ns of UTC;
.9 be capable of
selecting automatically the appropriate satellite-transmitted signals to
determine the ship’s position and velocity, and time with the required accuracy
and update rate;
.10 be capable
of acquiring satellite signals with input signals having carrier levels in the
range of –128dBm to –118dBm. Once the satellite signals have been acquired, the
equipment should continue to operate satisfactorily with satellite signals
having carrier levels down to –131dBm;
.11 be capable
of operating satisfactorily under normal interference conditions consistent
with the requirements of resolution A.694(17);
.12 be capable
of acquiring position, velocity and time to the required accuracy within 5 min
when there is no valid almanac data (cold start);
.13 be capable
of acquiring position, velocity and time to the required accuracy within 1 min
when there is valid almanac data (warm start);
.14 be capable
of re-acquiring position, velocity and time to the required accuracy within 1
minute when there has been a service interruption of 60 s or less;
.15 generate and
output to a display and digital interface7 a new position solution
at least once every 1 s for conventional craft and at least once every 0.5 s
for high-speed craft;
.16 provide the
COG, SOG and UTC outputs, with a validity mark aligned with that on the
position output. The accuracy requirements for COG and SOG should not be inferior
to the relevant performance standards for heading8 and speed and
distance measuring equipment (SDME)9 and the accuracy should be
obtained under the various dynamic conditions that could be experienced onboard
ships;