公开(公告)号：US11663920B2

公开(公告)日：2023-05-30

申请号：US17023813

申请日：2020-09-17

Applicant: Beijing University of Posts and Telecommunications

Inventor： Wenjun Xu ,  Chang Deng ,  Ping Zhang ,  Zhi Zhang ,  Hui Gao ,  Zhiyong Feng

IPC: G08G5/00 ,  G06N20/10 ,  B64C39/02 ,  G01C21/34 ,  H04L12/18 ,  G06F18/23213

CPC classification number: G08G5/0013 ,  B64C39/024 ,  G01C21/3469 ,  G06F18/23213 ,  G06N20/10 ,  G08G5/0034 ,  G08G5/0069 ,  H04L12/185 ,  B64U2201/20

Abstract: Disclosed is a method of path optimization for an unmanned aerial vehicle (UAV). In the method, users and the positions of the users are obtained; the users are divided into K wireless multicast user groups; K initial hovering positions corresponding to the K wireless multicast user groups are determined; and a first shortest flying path connecting the K initial hovering positions is determined; and the initial hovering positions of the UAV are optimized to obtain K final hovering positions and a final flying path. The present disclosure also discloses a device of path optimization for a UAV and a computer readable storage medium.

公开(公告)号：US12088438B2

公开(公告)日：2024-09-10

申请号：US17679911

申请日：2022-02-24

Applicant: Beijing University of Posts and Telecommunications

Inventor： Wenjun Xu ,  Tingting Zou ,  Hui Gao ,  Zhisong Bie ,  Ping Zhang ,  Fengyu Wang ,  Jiaru Lin

IPC: H04W24/02 ,  H04L25/03

CPC classification number: H04L25/03878 ,  H04W24/02

Abstract: Disclosed is a low-complexity linear equalization method for an Orthogonal Time Frequency Space (OTFS) system. The method may include: receiving a time domain signal passing through a linear time-varying (LTV) channel; sampling the time domain signal to obtain a sampled signal; demodulating the sampled signal to obtain a demodulated signal; performing a Symplectic Finite Fourier Transform (SFFT) on the demodulated signal to obtain a sampled delay-Doppler domain signal; determining an effective channel matrix in a delay-Doppler domain under a restriction of a rectangular window according to a time domain channel matrix; determining a linear equalization matrix according to the effective channel matrix; and equalizing the sampled delay-Doppler domain signal in a low-complexity way according to the linear equalization matrix. The disclosure also discloses a linear equalization device of an OTFS system for realizing the linear equalization method and a computer-readable storage medium.

公开(公告)号：US11283495B2

公开(公告)日：2022-03-22

申请号：US17393068

申请日：2021-08-03

Applicant: Beijing University of Posts and Telecommunications

Inventor： Wenjun Xu ,  Jinglin Zhang ,  Hui Gao ,  Zhiyong Feng ,  Zhi Zhang ,  Jiaru Lin

IPC: H04B7/0426 ,  H04B7/0456 ,  H04B7/06 ,  H04W4/02 ,  H04W4/40

Abstract: Disclosed are methods for beam tracking. In the methods, a transmitting unmanned aerial vehicle (UAV) receives motion state information (MSI) of a receiving UAV and determines a first beam angle from the transmitting UAV to the receiving UAV according to the MSI of the receiving UAV. Then the transmitting UAV selects a codeword from a codebook according to the first beam angle. Finally, the transmitting UAV determines an activated sub-array and a beam-forming vector of the CCA according to the size of the activated sub-array corresponding to the sub-codebook to which the codeword belongs, a second beam angle corresponding to the codeword and a location of a central antenna element of an activated sub-array corresponding to the codeword and transmits information using the beam-forming vector. One or more examples of the present disclosure also provide a method for beam tracking implemented by the receiving UAV, methods for generating a codebook.