Hunan Weidao was awarded the First Prize in Basic Science and Technology Progress Award by the Chinese Society of Metrology and Testing

The joint application of Hunan Weidao Information Technology Co., Ltd. and Beijing Institute of Metrology and Testing for "Research on Key Technologies for High Precision Application of GNSS in Complex Environments" won the first prize in the basic category of the 2021 China Society of Metrology and Testing Science and Technology Progress Award.
The first domestically and internationally developed high-precision GNSS simulation testing system for complex environments is the main technical research achievement of this project, and the measurement results are highly consistent with real scenes. This system can not only simulate complex multipath and signal occlusion scenes such as urban canyons, but also simulate special scenes such as Mount Everest, space, and cities.

The key technologies studied in the development of high-precision GNSS simulators in complex environments include:
Establishment of a Digital Model for Simulating Complex Scenes

• Establish a 15 order spherical function high fidelity meteorological parameter transmission model. Train the model using historical data from 200 global observation stations released by IGS over the past 10 years.
• Measure and establish a model unit library for the geometric shape and material reflection characteristics of surface objects. Ray tracing and error particle Evolutionary algorithm are used to build reflection and occlusion models of complex environment signals.
• Hardware Design and Development of GNSS Simulation System
• The parallel operation technology of shift register and phase accumulator and GPU acceleration technology are used to realize the Hardware acceleration of complex model operation and ensure the real-time output of high-precision signals.
• We have designed a high-resolution sub millisecond multi-level delay precise control circuit, dynamically configured components and software, and achieved high-speed synchronous synthesis of 64 multipath signals.
• Propose a dual channel mixing autocorrelation phase shift method to transfer the measurement of the simulator output signal from the time domain to the frequency domain, and improve the measurement accuracy from cm to 0.3mm.

Application in key fields:

1. Provide calibration for the GNSS receiver used for the 2020 Everest measurement.
2. Establish simulation testing scenarios for the Yangtze River, Lancang River, and their estuaries for the major demonstration project of Beidou application.
3. Application in the civilian field:
4. Provide metrological testing for the Guizhou high-speed railway track monitoring system, with a positioning error of no more than 1mm for 2km.
5. Provide metrological testing for the millimeter level high-precision positioning receiver of China Mobile's 5G high-precision service network.
6. Provide metrological testing for the millimeter level high-precision positioning receiver of China Unicom's 5G high-precision service network.
7. Carry out distance and time measurement test for Didi, Shouqi, Caocao, Yidao, Shenzhou and other major Ridesharing company platform companies.
8. We conducted metrological testing on intelligent positioning terminals and electronic fence algorithms for shared bike companies such as Mobike, Qingju, ofo, and Meituan.
9. Provide metrological testing for smart agricultural machinery of the Chinese Academy of Agricultural Sciences and Hezhong Sizhuang Company in Xinjiang, Heilongjiang, and other places.
10. Tested the digital engineering system and unmanned engineering vehicles for Hubei Wuhan International Logistics Airport.
11. Helped smartphone lane level navigation, intelligent agricultural machinery, and other similar GPS products to overtake on curves, leading the world.