本論文將針對循環字首正交分頻多工(Cyclic Prefix-OFDM)與補零正交分頻多工(Zero Padding-OFDM)系統,在時序同步(Time Synchronization)下的問題探討;由於時序偏移將造成符元間干擾(ISI),影響系統效能;我們將選用4種演算法估測時序偏移量,並針對CP-OFDM與ZP-OFDM的效能來比較。 The thesis takes a discussion on timing synchronization in cyclic-prefix Orthogonal Frequency Division Multiple (CP-OFDM) and Zero-padding Orthogonal Frequency Division Multiple(ZP-OFDM) systems.Time offset causes initer symbol interference(ISI) such that performance of the system attenuates.We will estimate time offset by using four different algorithms and comparison the performance of CP-OFDM and ZP-OFDM.