GB/T 39268-2020 in English

《GB/T 39268-2020低轨星载GNSS导航型接收机通用规范》由TC544（全国北斗卫星导航标准化技术委员会）归口，主管部门为中央军委装备发展部。

ChinaStandards.net is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative.

This standard is developed in accordance with the rules given in GB/T 1.1-2009.

This standard was proposed by the Equipment Development Department of Central Military Commission.

This standard is under the jurisdiction of the National Technical Committee on BeiDou Satellite Navigation System of Standardization Administration of China(SAC/TC 544).


General specification for GNSS navigation receivers onboard low earth orbit satellite

1 Scope

This standard specifies the technical requirements, test methods, inspection rules, as well as labeling, packaging, Transport and storage of GNSS navigation receivers onboard low earth orbit satellite.

This standard is applicable to the development, production, testing, application and inspection of GNSS navigation receivers onboard low earth orbit satellite. Other GNSS navigation receivers for low earth orbit (LEO) spacecraft may also be used for reference.

2 Normative references

The following referenced documents are indispensable for the application of this standard. For dated references, only the edition cited applies. For undated reference, the latest edition of the referenced documents (including any amendments) applies.

GB/T 9969 General principles for preparation of instructions for use of industrial products
GB/T 32304 Electrostatic discharge protection requirements for aerospace electronic products
GB/T 39267 Terminology for BeiDou navigation satellite system (BDS)
QJ 1417-1988 Reliability parts derating criteria
QJ 1729 Test methods for aerospace antenna
QJ 1947 Definitions of terms for antennas
QJ 2172-1991 Guide to satellite reliability design
GJ 2266 Electromagnetic compatibility requirements for space systems
QJ 2438 Technological requirements for packaging spacecraft
QJ 2630.1 Space environment test methods for spacecraft modules—Part 1: Thermal vacuum test
QJ 2630.2 Space environment test method for satellite units—Thermal Balance test
QJ 2630.3 Space environment test methods for spacecraft modules—Part 3: Vacuum discharge test
QJ 20073 Requirements and test methods of satellite electromagnetic compatibility
QJ 20422.6 Environment test methods for spacecraft unit—Part 6: Acceleration test
QJ 20422.7 Environment test methods for spacecraft unit—Part 7: Vibration test
QJ 20422.9 Environment test methods for spacecraft unit—Part 7: Impact test

3 Terms and definitions, Abbreviations

3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in GB/T 39267 and QJ 1947 and the following apply.

3.1.1
acquisition sensitivity
required lowest signal level when a receiver captures navigation signals and conducts normal positioning after being started up in a time when approximate position, approximate time, ephemeris and almanac are unknown

3.1.2
antenna gain
ratio of radiation intensity of an omni-directional antenna in the case that radiation intensity of the antenna in a given direction is the same as input power

Note 1: If the direction is not given, it refers to the direction of the maximum radiation intensity of the given antenna.

Note 2: If the antenna has no loss, it means that the absolute gain of the antenna in a given direction is the same as its directivity coefficient in numerical value.

Note 3: Usually expressed in decibels.

3.1.3
axial ratio
ratio of long axis to short axis of elliptically polarized wave

3.1.4
GNSS signal simulator
equipment for simulating the generation of GNSS satellite signals, which usually is used for testing, inspecting and calibrating receivers

Note: It is usually used for testing, inspection and calibration of the receiver. Generally, it includes data simulation and ratio frequency (RF) signal simulation.

3.1.5
orbital elements
a set of parameters describing the running status of a satellite in its orbit

Note: It includes orbital semi-major axis, orbital eccentricity ratio, orbital inclination, right ascension of ascending node, perigee argument, and mean anomaly.

3.1.6
technical specification
relevant technical requirements documents issued by a satellite developer to a receiver developer

Note: It generally includes satellite design and construction specifications, interface data sheets, environmental test specifications.

3.1.7
single event latch-up
state in which low resistance and high current is formed after single high-energy particle triggers and turns on a parasitic thyristor in a device

3.1.8
test scenario
series of configurations of test signals to complete specific functions and performance tests

Note: These configurations include navigation constellation and signal configuration, signal propagation environment configuration and receiver dynamic configuration.

3.1.9
time to first fix (TTFF)
time required for the receiver to acquire the correct fixing for the first time

3.1.10
total dose radiation hardness
sum of the maximum radiation dose that a material or device can bear

3.1.11
tracking sensitivity
required lowest signal level for maintaining navigation signal tracking and normal fixing after the receiver conducts normal fixing

3.2 Abbreviations

For the purposes of this standard, the following abbreviations apply.

1PPS: 1 pulse per second

BDCS: BeiDou coordinate system

BDS: Beidou Navigation Satellite System

CVCM: collected volatile condensable material
Galileo: Galileo navigation satellite system

GLONASS: GLObal navigation satellite system

GNSS: global navigation satellite system

GPS: global positioning system

PDOP: position diligence of precision

RMS: root mean square

TML: total mass loss

WGS-84: world geodetic system 1984

4 Requirements

4.1 Composition

GNSS navigation receivers onboard low earth orbit satellite (hereinafter referred to as "the receiver") shall include the following components:

a) GNSS antenna, including antenna body, antenna housing (optional) and antenna stand (optional);

b) Complete receiver machine or receiver board (hereinafter referred to as GNSS host);

c) Accessories (including cables, connector protection sockets).

4.2 Structure and appearance

The receiver structure and appearance requirements are as follows:

a) The surface of GNSS antenna generally requires spraying thermal control coating or complying with regulations of technical specification;

b) There is no trace of thermal control coating treatment on the inner wall of antenna mounting hole, and there shall not be thermal control coating on the mounting surface;

c) GNSS host shall be equipped with sufficient rigidity and mechanical strength;

d) The board shall be treated with moisture-proof, mould-proof and salt mist proof;

e) The external surface of each component shall be free from such defects as dents, scratches, cracks or deformations.

f) The coating (plating) shall not be blistered, cracked or fall off;

g) Metal parts shall not be corroded or has other mechanical damages.

h) The fasteners shall be free of looseness.

4.3 Labeling

The labeling requirements of the receiver are as follows:

a) Words, symbols and marks shall be clear.

b) Product code and batch number shall be on the product.

Foreword i
1 Scope
2 Normative references
3 Terms and definitions, Abbreviations
3.1 Terms and definitions
3.2 Abbreviations
4 Requirements
4.1 Composition
4.2 Structure and appearance
4.3 Labeling
4.4 Components and raw materials
4.5 Mechanical, electrical and thermal interfaces
4.6 Function requirements
4.7 Performance requirements
4.8 Requirements for environmental adaptability
4.9 Reliability
4.10 Safety
4.11 Electromagnetic compatibility
5 Test methods
5.1 Test environment conditions
5.2 Test equipment
5.3 Composition inspection
5.4 Structure and appearance inspection
5.5 Labelling inspection
5.6 Inspection of components and raw materials
5.7 Inspection of mechanical, electrical and thermal interfaces
5.8 Function test
5.9 Performance test
5.10 Environmental adaptability test
5.11 Reliability inspection
5.12 Safety inspection
5.13 EMC test
6 Inspection rules
6.1 Inspection classification
6.2 Appraisal inspection
6.3 Acceptance inspection
6.4 Inspection items and sequence
6.5 Judgment rules
7 Labeling, packaging, transport and storage
7.1 Labeling
7.2 Packaging
7.3 Transport and storage
8 Instructions for use
8.1 Preparation of instruction for use
8.2 Verification method of instructions for use
Annex A (Informative) GNSS signal frequency point and bandwidth
Annex B (Informative) Setting method of typical LEO dynamic test scenario
Annex C (Informative) Typical test conditions of environmental adaptability