Beam tracking method, apparatus, and system

A beam tracking method comprising:

• obtaining, by a communications device, a channel relevance coefficient, and determining a first radio-frequency weighted matrix of the communications device in an (n+1)th timeslot according to the channel relevance coefficient, wherein n is an integer, and n≥1;
• receiving, by the communications device, a first known signal sent by a peer device, and determining an equivalent channel matrix in the (n+1)th timeslot according to the received first known signal, wherein the first known signal is sent by the peer device to the communications device according to a second radio-frequency weighted matrix of the peer device in the (n+1)th timeslot and the first radio-frequency weighted matrix of the communications device in the (n+1)th timeslot;
• and
• determining, by the communications device, a digital weighted matrix of the communications device in the (n+1)th timeslot according to the equivalent channel matrix, so as to match a real-time channel and transmit data by using the real-time channel;
• wherein the obtaining, by the communications device, the channel relevance coefficient, and determining the first radio-frequency weighted matrix of the communications device in the (n+1)th timeslot according to the channel relevance coefficient comprises:
• obtaining, by the communications device, the channel relevance coefficient;
• generating, by the communications device, a basic codebook matrix set according to a criterion for minimizing maximum relevance between codebooks;
• determining, by the communications device, an update codebook matrix set according to the channel relevance coefficient and the basic codebook matrix set, wherein the update codebook matrix set is used to update weighting coefficients of all column vectors in a first radio-frequency weighted matrix of the communications device in an nth timeslot;
• updating, by the communications device, the weighting coefficients of all the column vectors in the first radio-frequency weighted matrix in the nth timeslot according to the update codebook matrix set, and obtaining a candidate codebook matrix set of the first radio-frequency weighted matrix of the communications device in the (n+1)th timeslot;
• and
• determining, by the communications device, the first radio-frequency weighted matrix of the communications device in the (n+1)th timeslot from the candidate codebook matrix set according to a preset criterion.