A phase adjustment method, a related device, and a system, the method comprising obtaining phases and amplitudes of M symbols adjusting a phase of each of the M symbols to an adjusted phase, wherein the adjusting the phase of each of the M symbols to the adjusted phase includes performing at least one of setting the adjusted phase of the first symbol to the phase of the respective symbol, or setting the adjusted phase of a symbol greater than the first symbol according to the phase of the respective symbol and further according to a sum of phases of all symbols whose amplitudes are greater than an amplitude threshold in a group of one or more symbols from a first symbol to an (i−1)th symbol.