公开(公告)号：US20190095730A1

公开(公告)日：2019-03-28

申请号：US16136128

申请日：2018-09-19

Applicant: Beijing University of Posts and Telecommunications

Inventor： Huiyuan FU ,  Huadong MA ,  Yifan ZHANG ,  Yu CAO ,  Dengkui ZHANG

IPC: G06K9/00 ,  G06K9/46 ,  G06T3/40 ,  G06N3/08

Abstract: Embodiments of the present invention provide an end-to-end lightweight method and apparatus for license plate recognition. The method comprises: obtaining an image to be recognized; obtaining a number of a license plate in the image to be recognized and position coordinates of the license plate in the image to be recognized on the basis of the image to be recognized and a pre-trained target license plate recognition model, wherein the target license plate recognition model comprises a target feature extraction network, a target region candidate localization network, a target super-resolution generation network and a target recurrent neural network. Because in this solution, once an image to be recognized is input into the target license plate recognition model, the target license plate recognition model can output the license plate number and position coordinates of the license plate in the image to be recognized, one realizes an end-to-end model. The model has relatively strong robustness, and it can detect and recognize pictures taken under different camera angles. Moreover, computation variables such as image features can be reused without repeated computations, the model takes up less RAM and the speed of license plate recognition is greatly improved.

公开(公告)号：US20240039590A1

公开(公告)日：2024-02-01

申请号：US18026433

申请日：2021-12-27

Applicant: Beijing University Of Posts and Telecommunications

Inventor： Qixun ZHANG ,  Zhiyong FENG ,  Huan SUN ,  Ping ZHANG ,  Zhiqing WEI ,  Sai HUANG ,  Yifan ZHANG

IPC: H04B7/06 ,  H04B7/08

CPC classification number: H04B7/0617 ,  H04B7/086

Abstract: A broadband millimeter wave beam tracking method based on vehicle movement trajectory recognition, which relates to the field of wireless communication. First, a rough estimate of the beam angle is obtained according to the position and attitude of two vehicles in a communication scenario at an initial moment, and a state of the vehicle is judged according to the sudden change rate of the transmitting beam angle starting from a next moment; if it is in the sudden change mode, the observation value ŷk of the received signal is calculated; if it is in the smooth change mode, the observation value I is calculated; the observation values in different modes are input into an improved particle filter algorithm for fine beam estimation, to obtain optimal values xk and uk; and the beam optimal values at the current moment are used to re-estimate a pair of the forming vector of the transmitting beam and the forming vector of the receiving beam to adjust the vehicle and the pilot signal at the next moment is transmitted; by continuously adjusting the beam forming vector at each moment, a beam tracking within an error range is obtained. The present application improves the accuracy and reliability of beam tracking in case of sudden angle change.