RESOLUTION
MSC.379(93)
(adopted on 16 May 2014)
PERFORMANCE
STANDARDS FOR SHIPBORNE BEIDOU SATELLITE NAVIGATION SYSTEM (BDS) RECEIVER
EQUIPMENT
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.1046(27), containing the IMO
policy for the recognition and acceptance of suitable radionavigation systems
intended for international use, the "Revised Report on the Study of a
Worldwide Radionavigation System", the BDS satellite navigation system may
be recognized as a possible component of the world-wide radionavigation system,
NOTING that shipborne receiving equipment for the worldwide
radionavigation system should be designed to satisfy the detailed requirements
of the particular system concerned,
RECOGNIZING the need to develop performance standards for
shipborne BDS 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-ninth session,
1 ADOPTS the
performance standards for shipborne BDS receiver equipment, set out in the
annex to the present resolution;
2 RECOMMENDS Governments
to ensure that BDS receiver equipment installed on or after 1 July 2016 conform
to performance standards not inferior to those specified in the annex to the
present resolution.
ANNEX
PERFORMANCE
STANDARDS FOR SHIPBORNE BEIDOU SATELLITE NAVIGATION SYSTEM (BDS) RECEIVER
EQUIPMENT
1 Introduction
1.1 As a global
navigation satellite system compatible with other navigation satellite systems
worldwide, the BDS is a system independently developed and operated by China
and is comprised of three major components: space constellation, ground control
segment and user terminals. The space constellation consists of five
geosynchronous earth orbit (GEO) satellites and 27 medium-earth orbit (MEO)
satellites and three inclined geosynchronous satellite orbit (IGSO) satellites.
The GEO satellites are positioned at longitudes of 058.75° E, 080° E, 110.5° E,
140° E and 160° E, respectively. The MEO satellites are operating in an orbit
with an altitude of 21,500 km and an inclination of 55°, which are evenly distributed
in three orbital planes. The IGSO satellites are operating in an orbit with an
altitude of 36,000 km and an inclination of 55°, which are evenly distributed
in three inclined geosynchronous orbital planes. The subsatellite track for the
three IGSO satellites are coincided while the longitude of the intersection
point is at 118° E. This geometry ensures that a minimum of four satellites are
visible to users worldwide with a position dilution of precision (PDOP) ≤
6. Each satellite transmits open service signal B1I on "L" bands with
carrier frequency as 1561.098 MHz. B1I signal includes ranging code which could
provide the open service. A navigation data message is superimposed on this
code. BDS satellites are identified by Code Division Multiple Access (CDMA).
1.2 The BDS Open
Service (OS) provides positioning, navigation and timing services, free of
direct user charges. The BDS receiver equipment should be capable of receiving
and processing the open service signal.
1.3 BDS receiver
equipment intended for navigational purposes on ships with a speed not
exceeding 70 knots, in addition to the general requirements specified in
resolution A.694(17)1,
should comply with the following minimum performance requirements.
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1Refer to publication IEC 60945
1.4 The 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 other computational
facilities which may be in the equipment nor cover the requirements for other
systems that may take input from the BDS receiver.
2 BDS receiver
equipment
2.1 The term "BDS receiver equipment" as used in the
performance standards includes all the components and units necessary for the
system to properly perform its intended functions. The BDS receiver equipment
should include the following minimum facilities:
.1 antenna
capable of receiving BDS signals;
.2 BDS
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.
If BDS forms part of an approved Integrated Navigation System
(INS), 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 BDS receiver equipment
The BDS receiver equipment should:
.1 be capable of receiving and processing
the BDS positioning and velocity, and timing signals, and should use the
ionospheric model broadcast to the receiver by the constellation to generate
ionospheric corrections;
.2 provide position information in latitude
and longitude in degrees, minutes and thousandths of minutes2;
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2BeiDou
uses China Geodetic Coordinate System (CGCS) 2000 which is a realization of the
International Terrestrial Reference Frame (ITRF) system and differs from WGS 84
by less than 5 cm worldwide. Conversion to WGS 84 is not needed for maritime
navigation.
.3 provide time referenced to universal
time coordinated UTC (NTSC)3;
_____________________
3China
National Time Service Centre.
.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 WGS 84 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 3.15 and 3.17;
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4Publication
IEC 61162.
.5 have static accuracy such that the
position of the antenna is determined to be within 25 m horizontally (95%) and
30 m vertically (95%);
.6 have dynamic accuracy equivalent to the
static accuracy specified in .5 above under the normal sea states and motion
experienced in ships5;
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5Refer
to resolution A.694(17),
publications IEC 6721-3-6 and IEC 60945.
.7 have position information in latitude
and longitude in degrees, minutes and thousandths of minutes with a position
resolution equal to or better than 0.001 min of latitude and longitude;
.8 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;
.9 be capable of acquiring satellite
signals with input signals having carrier levels in the range of -130dBm to
-120dBm. Once the satellite signals have been acquired, the equipment should
continue to operate satisfactorily with satellite signals having carrier levels
down to -133dBm;
.10 be capable of operating satisfactorily
under normal interference conditions consistent with the requirements of
resolution A.694(17);
.11 be capable of acquiring position, velocity
and time to the required accuracy within 12 min where there is no valid almanac
data;
.12 be capable of acquiring position, velocity
and time to the required accuracy within 1 min where there is valid almanac
data;
.13 be capable of reacquiring position,
velocity and time to the required accuracy within 1 min when there has been a
service interruption of 60 s or less;
.14 generate and output to a display and
digital interface6 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;
_____________________
6Publication
IEC 61162.
.15 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 heading7 and speed and distance measuring equipment
(SDME)8 and the accuracy should be obtained under the various
dynamic conditions that could be experienced on board ships;
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7Resolution
A.424(XI) for
conventional craft and resolution A.821(19) for high-speed craft.
8Resolution
A.824(19), as
amended by resolution MSC.96(72).
.16 provide at least one normally closed
contact, which should indicate failure of the BDS receiver equipment;
.17 have a bidirectional interface to
facilitate communication so that alarms can be transferred to external systems
and so that audible alarms from the BDS receiver can be acknowledged from
external systems; the interface should comply with the relevant international
standards9; and
_____________________
9Publication
IEC 61162.
.18 have the facilities to process
differential BDS (DBDS) data fed to it in accordance with the standards of
ITU-R10 and the appropriate RTCM standard and provide indication of
the reception of DBDS signals and whether they are being applied to the ship's
position. When a BDS receiver is equipped with a differential receiver,
performance standards for static and dynamic accuracies (paragraphs 3.5 and 3.6
above) should be 10 m (95%).
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10ITU-R
Recommendation M.823.
4 Integrity
checking, failure warnings and status indications
4.1 The BDS receiver
equipment should also indicate whether the performance of BDS is outside the
bounds of requirements for general navigation in the ocean, coastal, port
approach and restricted waters, and inland waterway phases of the voyage as
specified in either resolution A.1046(27) or appendix 2 to resolution A.915(22) and any
subsequent amendments, as appropriate.
4.2 The BDS receiver equipment should, as a
minimum:
.1 provide a warning within 5 s of loss of
position or if a new position based on the information provided by the BDS
constellation has not been calculated for more than 1 s for conventional craft
and 0.5 s for high-speed craft. Under such conditions the last known position
and the time of last valid fix, with the explicit indication of the state
allowing for no ambiguity, should be output until normal operation is resumed;