The key and difficult to detect in the antenna attitude parameter is the azimuth angle.
At present, the azimuth angle of the antenna is mainly obtained by using the electronic compass and measurement to obtain the geomagnetic azimuth angle, and then the antenna azimuth angle is obtained through the local magnetic declination compensation. The main defect is the fear of interference from surrounding magnetic objects, and the tower pole itself is the source of interference, resulting in low monitoring accuracy, difficulty in repeated monitoring, and difficulty in adapting to the requirements of network optimization.
There is also orientation through GPS carrier phase differential. The reference carrier phase differential technology, also known as RTK (Real Time Kinematic) technology, is a differential method for real-time processing of the carrier phase observations of two stations. That is, the carrier phase collected by the base station is sent to the user receiver, and the difference is calculated to calculate the coordinates. Carrier phase difference enables positioning accuracy to the centimeter level. It is widely used in fields that require high-precision positions dynamically.
The main problems: 1. The GPS that can provide the original carrier phase is expensive; 2. At the same time, due to the requirement of the baseline length, the device is generally relatively long and cannot be easily installed above various antennas;
We adopted a high-precision sunlight-based azimuth detection method, whose detection principle is as follows: the rotation of the earth and the revolution of the earth around the sun cause the motion of the sun's position relative to the stationary object on the ground" This change is periodic and can be predicted". Therefore, the sun azimuth a z can be calculated according to the geographical location and time of the measurement site, combined with astronomical knowledge, and the final azimuth formula is as follows:
Suppose the azimuth angle of the antenna is φ, α is the pitch angle, γ is the roll angle, e l is the sun altitude angle, az is the sun azimuth angle, and β is the incident angle of the solar sensor;
Then the pitch angle and roll angle can be calculated by the acceleration sensor and the gyroscope sensor, and the incident angle of the solar sensor can be obtained by the solar sensor.
Welcome to contact us for AISG RET Control Cables: https://www.pcm-cable.com/aisg-cables/
