The disclosure provides satellite communication methods and related devices. One example method includes generating a random access preamble sequence which includes a cyclic prefix, a sequence part, and a guard interval. The sequence part includes a subsequence A and a subsequence B, or the sequence part includes a subsequence C, and the subsequence C is a time domain superimposed sequence of a subsequence A and a subsequence B. The subsequence A includes at least one preamble symbol, the subsequence B includes at least one preamble symbol, and the subsequence A and the subsequence B are respectively generated by using ZC sequences of different root indexes, a quantity of subsequences A is m, a quantity of subsequences B is m or m−1, and m is a positive integer. The method further includes outputting the random access preamble sequence.