公开(公告)号：US11719784B2

公开(公告)日：2023-08-08

申请号：US17481872

申请日：2021-09-22

申请人： Zhejiang University

发明人： Huifang Chen ,  Lei Xie ,  Feng Liu ,  Chenglei Lv ,  Wen Xu

IPC分类号： G01S5/26

CPC分类号： G01S5/26

摘要： A method for positioning an underwater glider based on a virtual TDOA of a single beacon is provided. In the method, a positioning beacon periodically sends positioning messages, where the positioning message includes longitude, latitude and depth information of the positioning beacon; the underwater glider receives the positioning messages and records TOAs at which the positioning messages arrive at an acoustic positioning signal receiving module; and the underwater glider parses the positioning messages and stores positioning message data, creates virtual beacons based on beacon information and attitude information of the underwater glider, corrects the TOAs, and calculates a position of the underwater glider according to a TDOA algorithm. According to the method, the underwater glider passively listens to and receives the positioning messages without sending a positioning request to the positioning beacon, making the entire positioning process energy-saving with a certain degree of concealment.

公开(公告)号：US20220128647A1

公开(公告)日：2022-04-28

申请号：US17481872

申请日：2021-09-22

申请人： Zhejiang University

发明人： Huifang Chen ,  Lei Xie ,  Feng Liu ,  Chenglei Lv ,  Wen Xu

IPC分类号： G01S5/26

摘要： A method for positioning an underwater glider based on a virtual TDOA of a single beacon is provided. In the method, a positioning beacon periodically sends positioning messages, where the positioning message includes longitude, latitude and depth information of the positioning beacon; the underwater glider receives the positioning messages and records TOAs at which the positioning messages arrive at an acoustic positioning signal receiving module; and the underwater glider parses the positioning messages and stores positioning message data, creates virtual beacons based on beacon information and attitude information of the underwater glider, corrects the TOAs, and calculates a position of the underwater glider according to a TDOA algorithm. According to the method, the underwater glider passively listens to and receives the positioning messages without sending a positioning request to the positioning beacon, making the entire positioning process energy-saving with a certain degree of concealment.

公开(公告)号：US11469777B2

公开(公告)日：2022-10-11

申请号：US17336717

申请日：2021-06-02

申请人： Zhejiang University

发明人： Lei Xie ,  Huifang Chen ,  Hongda Duan

IPC分类号： H03M13/11 ,  H03M13/00 ,  H04B11/00 ,  H04B13/02

摘要： The present disclosure provides a method for optimizing a protograph-based LDPC code over an underwater acoustic (UAW) channel. The traditional protograph-based LDPC code over an UAW channel does not consider performance in an error floor region. The method first determines parameters such as a protograph-based LDPC code length, a basic protograph, a target decoding threshold, a threshold adjustment factor, and an ACE check parameter. The protograph is optimized, and the method constructs a parity check matrix by using a UAW channel-based PEG/ACE hybrid algorithm, performs ACE check on the parity check matrix, and calculates a decoding threshold for the matrix passing the check. If the decoding threshold is within a range of an iterative decoding threshold, the parity check matrix is a final optimized matrix. Otherwise, the method continues to optimize the protograph until a parity check matrix passing the check is obtained.