Decryption of Hexinxingtong's multi-antenna positioning measurement to help Beidou system

Unicore Navigation is one of the earliest companies in my country to enter the research and development of navigation chips. It is engaged in high-integration chip design and high-performance GNSS core algorithm research and development, and has released the first SoC chip that supports the "full Beidou" (RNSS+RDSS) working mode, providing strong support for my country's Beidou satellite navigation system in high-precision measurement, mapping, navigation and other aspects.

The Global Navigation Satellite System (GNSS) can be widely used in various fields. For example, carrier phase measurements can be used for real-time positioning and attitude measurement. Compared with conventional methods, it has obvious advantages such as high accuracy and no error accumulation over time. It can play an important role in attitude measurement and control, precision machinery control, target three-dimensional measurement, agricultural plant protection and other related fields.

In order to improve the accuracy and reliability of positioning measurement, Unicore Starlink Co., Ltd. applied for an invention patent entitled "A method and device for positioning and attitude measurement of GNSS multi-antenna receivers" on April 1, 2019 (application number: 201910257329.9), and the applicant was Unicore Starlink Technology (Beijing) Co., Ltd.

Figure 1 Flowchart of a method for positioning and attitude measurement using a GNSS multi-antenna receiver

FIG1 is a positioning measurement method provided by the present invention, which can be applied to a user receiver with multiple antennas. First, the satellite observation data and coordinate information of the antennas on the user receiver and the base station are obtained (101). As shown in FIG2, the receiver includes a main antenna A1 and a slave antenna A2. Then, for the data received on the base station and the user receiver antenna, a double difference observation equation is established, and the first baseline vector between the base station and the antenna and the second baseline vectors B0A1, B0A2, A1A2 between the two antennas are solved (102, 103). Finally, according to the above baseline vectors, the positioning attitude information, such as antenna coordinates, carrier position, etc., is determined (104).

Figure 2 Example of positioning application scenario

When multiple distributed signal antennas are fixed on the carrier, higher-precision attitude measurement can be achieved. A baseline composed of two antennas can obtain two attitude angles, and two coplanar, non-parallel baselines composed of three antennas can obtain three-dimensional attitude angles (yaw angle, pitch angle, roll angle). When there are more and relatively fixed antenna arrays, more available prior information and geometric conditions can be provided, thereby improving the accuracy and robustness of positioning and attitude measurement.

Figure 3 GNSS multi-antenna receiver positioning and attitude measurement device

Referring to FIG3 , the present invention provides a device for positioning and measuring attitude of a multi-antenna receiver, including a measurement information acquisition module 501, an antenna positioning module 502, an antenna orientation module 503, and a positioning and measuring attitude module 504. The measurement information acquisition module 501 can obtain satellite observation data of the antenna on the user receiver, satellite observation data and coordinate information of the reference station; the antenna positioning module 502 establishes a double difference observation equation for the satellite observation data of the reference station and the antenna, and solves and obtains a first baseline vector; similarly, the antenna orientation module 503 can obtain a second baseline vector between antennas; the positioning and measuring attitude module 504 determines the positioning and measuring attitude information according to the fixation of the first baseline vector and the second baseline vector.

The above is the introduction of Unicore Starlink’s high-precision positioning measurement method for GNSS multi-antenna receivers. This invention obtains satellite observation data and coordinate information on each antenna of the user receiver, establishes a double-difference observation equation, solves the baseline vector, and then obtains positioning measurement information.

Through years of innovative research and development in the navigation field, Unicore Navigation Technology has continuously filled domestic gaps and gradually improved the chip shortage situation in domestic infrastructure construction.