Multi-GNSS precise point positioning for precision agriculture

Jing Guo,Maorong Ge,David Fairbairn,Zhenhong Li,Xingxing Li,Leyin Hu,David Watson,Chunjiang Zhao,Guijun Yang

doi:10.1007/s11119-018-9563-8

Abstract

The main objective of this research was to examine the feasibility of Multi-GNSS precise point positioning (PPP) in precision agriculture (PA) through a series of experiments with different working modes (i.e. stationary and moving) under different observation conditions (e.g. open sky, with buildings or with canopy). For the stationary test carried out in open space in the UK, the positioning accuracy achieved was 13.9 mm in one dimension by a PPP approach, and the repeatability of positioning results was improved from 19.0 to 6.0 mm by using Multi-GNSS with respect to GPS only. For the moving test carried out in similar location in the UK, almost the same performance was achieved by GPS-only and by Multi-GNSS PPP. However, for a moving experiment carried out in China with obstruction conditions, Multi-GNSS improved the accuracy of baseline length from 126.0 to 35.0 mm and the repeatability from 110.0 mm to 49.0 mm, The results suggested that the addition of the BeiDou, Galileo and GLONASS systems to the standard GPS-only processing improved the positioning repeatability, while a positioning accuracy was achieved at about 20 mm level in the horizontal direction with an improvement against the GPS-only PPP results. In space-constrained and harsh environments (e.g. farms surrounded with dense trees), the availability and reliability of precise positioning decreased dramatically for the GPS-only PPP results, but limited impacts were observed for Multi-GNSS PPP. In addition, compared to real time kinematic (RTK) GNSS, which is currently most commonly used for high precision PA applications, similar accuracy has been achieved by PPP. In contrast to RTK GNSS, PPP can provide high accuracy positioning with higher flexibility and potentially lower capital and running costs. Hence, PPP might be a great opportunity for agriculture to meet the high accuracy requirements of PA in the near future.

Highlights

Emerging in the mid-1980s, precision agriculture (PA) is a farming management concept based on observing, measuring and responding to the spatio-temporal variability in weather, soil and agricultural production
In PA, it is well recognized that Global Navigation Satellite Systems (GNSS) are the major enabler of ‘precision’ (Larsen et al 1994; Krüger et al 1994)
The space segment of Beidou Navigation Satellite System (BeiDou) will consist of 5 Geostationary Orbit (GEO), 3 Inclined Geosynchronous Orbit (IGSO), and 27 Medium Earth Orbit (MEO) satellites (CSNO 2013)

Summary

Introduction

Emerging in the mid-1980s, precision agriculture (PA) is a farming management concept based on observing, measuring and responding to the spatio-temporal variability in weather, soil and agricultural production. GNSS represents a constellation of satellites providing signals from space, transmitting positioning and timing data with global coverage. The new and emerging BeiDou and Galileo systems provide potential for more precise and reliable GNSS applications and services around the world, or in certain regions. BeiDou, declared to be operational to provide regional PNT services in December 2012, consisted of 5 Geostationary Orbit (GEO), 5 Inclined Geosynchronous Orbit (IGSO), and 4 Medium Earth Orbit (MEO) satellites. With the launch of new generation BeiDou IGSO and MEO satellites in 2015 and 2016, the system is starting to become a global navigation satellite system, and this phase will be completed in 2020. The initial services started on 15 December 2016, and the full operation of the Galileo constellation will be accomplished with 30 satellites in three orbital planes in 2020 (EU 2016). Increasing the number of operational systems is expected to improve the observation geometry, which in turn will benefit the positioning accuracy, availability, integrity and continuity

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Conclusion