Method for measuring antenna downtilt angle based on deep instance segmentation network
A method for measuring an antenna downtilt angle based on a deep instance segmentation network is disclosed, including: shooting an omni-directional antenna video using a drone; and transmitting the antenna video to a server in real time, and the server measuring an antenna downtilt angle in real time using a deep learning algorithm, the deep learning algorithm includes: a feature extraction network module for acquiring an antenna feature image; an instance segmentation module for binary segmentation of an antenna image and the background to distinguish antenna image pixels from background pixels; an antenna candidate box module for identifying and detecting the antenna image, acquiring an antenna candidate box and determining an antenna calibration box therefrom; and an antenna downtilt angle measuring module for measuring an antenna downtilt angle.
1. A method for measuring an antenna downtilt angle based on a deep instance segmentation network, comprising:
shooting an omni-directional antenna video using a drone; and
transmitting the antenna video to a server in real time, and the server measuring an antenna downtilt angle in real time using a deep learning algorithm,
wherein the deep learning algorithm comprises: a feature extraction network module for acquiring an antenna feature image; an instance segmentation module for binary segmentation of an antenna image and the background to distinguish antenna image pixels from background pixels; an antenna candidate box module for identifying and detecting the antenna image, acquiring an antenna candidate box and determining an antenna calibration box therefrom; and an antenna downtilt angle measuring module for measuring an antenna downtilt angle; and
the instance segmentation module comprises: directly mapping a region of interest to a feature map; segmenting a candidate region into k*k cells, determining, for each cell, four fixed coordinate positions of the center point of the cell, and calculating values of the four fixed coordinate positions using bilinear interpolation; and performing max-pooling and implementing back propagation.
2. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 1 , wherein the shooting an omni-directional antenna video using a drone comprises: controlling the drone to fly around in a circle with an antenna as the origin and a radius of r meters from the antenna at a height of h meters from the antenna, and shooting a 360-degree omni-directional antenna video.
3. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 2 , wherein the feature extraction network module comprises a residual network for solving gradient problems and network performance degradation problems and a feature pyramid network for solving multi-scale detection problems.
4. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 1 , wherein the back propagation formula of the instance segmentation module is
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wherein x i represents a pixel point on the feature map before max-pooling; y rj represents the j th point in the r th candidate region after max-pooling; i*(r, j) represents coordinates of the pixel point before max-pooling corresponding to a pixel value of the point y rj ; x i *(r, f) represents coordinates of sampling points calculated during back propagation, d(⋅) denotes a distance between two points, and Δh and Δw denote differences of horizontal and vertical coordinates of x i and x i *(r, j).
5. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 1 , wherein the antenna candidate box module is a candidate box selection module using a faster RCNN network structure.
6. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 5 , wherein the antenna candidate box module's target loss function is
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wherein L cls is a classification loss function, and its expression is:
L cls ( p i ,p i *)=−log[ p i *p i +(1− p i *)(1− p i )];
L reg is a regression loss function, and its expression is: L reg (t i ,t i *)=R(t i −t i *); and
an R function is defined as
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7. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 1 , wherein the antenna downtilt angle measuring module obtains a region with a minimum relative proportion by comparing a relative proportion between the antenna calibration box and a region represented by the antenna image pixels.
8. The method for measuring an antenna downtilt angle based on a deep instance segmentation network according to claim 7 , wherein the antenna downtilt angle measuring module measures the antenna downtilt angle based on the following formula:
0
=
arctan
x
y
,
where x is the width of the calibration box, and y is the length of the calibration box.