Abstract: A communication method and communication system using two-dimensional primary synchronization signals are provided. The communication system includes a base station and a user equipment. The communication method includes: providing a two-dimensional synchronization array collection having a zero correlation zone; generating plural primary synchronization signals (PSSs) in accordance with the two-dimensional synchronization array collection; generating a synchronization signal block (SSB) in accordance with the primary synchronization signals, in which the synchronization signal block is adapted for new radio (NR) technology, and each one of the primary synchronization signals corresponds to plural orthogonal frequency division multiplexing (OFDM) symbols and plural subcarrier signals; and performing a communication operation by using the synchronization signal block.

Abstract: A spatial modulation system and a method for generating training sequences are provided. The method for generating training sequences includes: obtaining a cross Z-complementary set (CZCS); and obtaining a training sequence matrix according to cross Z-complementary sequences in the CZCS. Therefore, a larger zero correlation zone (ZCZ) width can be constructed, and the constructed sequence set has flexible lengths.