Compared with GPS, the dual micro RTK basically flies in a straight line with small curvature
What are the problems with using dual micro RTK technology?
The base station setting and operating radius directly affect the measurement accuracy and operating speed of dual micro RTK. The reference station shall be set at a high place as far as possible, away from strong electromagnetic interference sources and large-area signal reflectors. The dual micro RTK technology itself depends on GPS satellite positioning. Its use requires phase observation and tracking of more than four satellites and necessary geometry. If the GPS signal received by the positioning itself is poor, the dual micro RTK is useless. In addition, there are places where large-area signal reflectors cannot be located, such as dense forests near high-rise buildings; Strong electric and magnetic sources can also interfere with signals, such as near high-voltage power lines, near substations and when clouds are thick.
The route coordinates obtained by the aircraft during operation are not a straight line, but a wide area. If GPS positioning is used for route operation, the area width is within 0 ~ 10m. In this case, the actual flight trajectory of the aircraft will be a curved curve, and the curve of each flight is inconsistent.
When using dual micro RTK, the route will be a 0-10 cm wide area. Compared with GPS, the dual micro RTK basically flies in a straight line with small curvature, so the effect will be more uniform and controllable. Working principle of dual micro RTK measurement: one receiver is placed at the reference station, and another or more receivers are placed on the carrier (called mobile station). The base station and mobile station simultaneously transmit and receive signals from the same GPS satellite. The observation value obtained by the base station is compared with the known position information to obtain the GPS differential correction value. Then, the corrected value is transmitted to the common view satellite mobile station through the radio data link station in time, and the GPS observation value is refined, so that the real-time position of the mobile station after differential correction is more accurate.
At present, the mainstream dual micro RTK Positioning Accuracy plane can reach 8mm + 1ppm, and the elevation angle can reach 15mm + 1ppm. There are mainly two communication modes between the base station and the mobile station: Radio and network. The radio signal is stable and the network signal is transmitted far. Each has its own advantages. In some field operations with large row spacing, such as large offset, secondary hazards such as leakage of most crops, spraying and land pollution may even occur. In short, the dual micro RTK improves the positioning accuracy and expands the application scenario of GPS positioning technology. In the future, there will be more places for double micro RTK to work. It will be integrated into all stages of crop growth to help us obtain real-time space-time information of any position in the field, and then match the corresponding equipment to realize the timely, fixed-point and quantitative release of pesticides and fertilizers, and achieve economic and environmental benefits. In addition to plant protection, high-precision real-time positioning can also assist in rural land survey and land ownership confirmation, and provide high-precision navigation and data services for unmanned automatic equipment in other farmland.