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China has introduced a new recommended technical standard (GB/T 45086.1-2024) for automotive GNSS receivers. OEMs and Tier 1 suppliers focused on the Chinese market may be required to demonstrate conformance with the standard, and should have test equipment and scenarios ready for that eventuality.
The new standard, Technical requirements and test methods for on-board positioning system—Part 1: Satellite positioning, has been developed by the Government of China. It sets out minimum requirements for an in-vehicle GNSS positioning, navigation and timing (PNT) system in terms of functionality, performance and robustness.
The standard is likely to underpin future safety legislation requiring Accident and Emergency Calling Systems (AECS) to be included in new vehicles for the Chinese market, similar to Europe’s eCall and Russia’s ERA-GLONASS initiatives. In addition to the benefit of assuring PNT performance for customers, early adopters of this recommendation could secure a competitive advantage when AECS becomes mandatory.
GNSS receiver functional requirements
Three areas are addressed by the new standard: functionality, performance and robustness of the GNSS receiver. In terms of functionality, to ensure continuity and accuracy, the receiver should be capable of receiving signals from all four global navigation satellite systems: GPS, GLONASS, Galileo and BeiDou. For BeiDou it should support dual or multiple frequency bands, either B1+B2, B1+B3, B2+B3, or B1+B2+B3.
As well as operating on a multi-GNSS, multi-frequency basis, it should also be capable of operating in BeiDou Independence mode (with BeiDou signals only), in BeiDou Priority mode (where BeiDou signals are acquired first), and in BeiDou Only mode (when only BeiDou signals are in view). Output should be in NMEA-0183 protocol format, and the hardware update rate should be minimum 1Hz.
GNSS receiver performance requirements
The automotive positioning GB/T standard defines receiver performance in four areas: accuracy, acquisition time, sensitivity and timing. Receivers will be required to demonstrate positioning accuracy in static and dynamic scenarios as well as at high velocity. Time to first fix (TTFF) will need to be measured at hot start (with previous position data already known) and cold start (with no previous position data known).
For sensitivity, receivers will need to meet specified standards for signal acquisition, signal tracking and reacquisition of the signal after loss of lock. The ability to acquire, track and reacquire signals at low power will also be measured. Timing relates to the receiver’s ability to accurately receive and output precise timing data from GNSS—for example to timestamp events leading up to an accident and the timing of the accident itself.
GNSS receiver robustness requirements
In terms of robustness, OEMs and Tier 1s will need to demonstrate that receivers are protected against malicious and unintentional interference that could impair their ability to calculate an accurate position. The standard emulates the European Union Radio Equipment Directive (RED) standard for robustness to in-band and adjacent-band interference from other electronic equipment. Evidence of robustness to jamming interference may also be required, as well as evidence of receiver resilience—the ability to recover from a disruption incident and return to normal operation.
Automotive positioning GB/T conformance testing using Spirent equipment
All of China’s leading automotive test houses are ready to conduct conformance tests on automotive vehicles and components. Test houses including China Automotive Engineering Research Institute (CAERI), National Automobile Quality Supervision and Test Center (NAST), Tianjin Automobile Testing Center (TATC) will use Spirent simulators and test scenarios to qualify positioning capabilities. Developers using Spirent simulation systems and bespoke GB/T test scenarios can be sure that testing in development and validation mirrors the later certification process, enabling them to be confident of passing independent third-party tests.
Suitable equipment and tools for conformance testing with the new automotive positioning GB/T standard include:
A multi-constellation, multi-frequency GNSS signal simulator with support for all four global constellations, such as the Spirent GSS7000 GNSS Simulator. Spirent supports testing of receivers moving at high speeds and with high acceleration, giving manufacturers confidence that receivers can comply with positioning accuracy standards in highly dynamic scenarios.
A scenario test set identical to the scenarios used by the leading automotive test labs in China. This can be obtained from Spirent for a faster start to conformance testing.
An (optional) test automation tool to accelerate testing and free up time and resources in the test lab.
Zoned chamber for OTA testing: Over-the-air testing of the antenna portion of the GNSS receiver can be conducted in a Spirent-patented ‘zoned chamber’ setup, in which satellite signals are broadcasted over-the-air. The patented zoned element of the chamber design means realistic satellite motion is mirrored, making testing more representative and extending scenario duration. Spirent can design and set up a zoned chamber for ultra-realistic OTA testing in repeatable lab conditions.
Accelerate the journey to safe autonomous driving
Few automotive GNSS-related standards exist today, but as the industry moves closer to hands-free driving, standards like automotive positioning GB/T 45086.1-2024 will become part of a much stricter regulatory environment around vehicle positioning systems. In the future we’re likely to see the introduction of aviation-grade safety standards, like RTCA DO-229, to support progression to SAE Level 3 vehicle autonomy and above.
Getting ahead of those standards now will allow OEMs, Tier 1s and chipset and module providers to capitalize earlier on demand for highly automated and autonomous driving. If you’d like to talk to Spirent about any aspect of testing conformance with new automotive positioning standards, please do get in touch.
