Communication channels (information theory) Error analysis Maximum likelihood estimation Synchronization Cyclic prefix (CP) Frequency synchronization Time variant multipath channel Orthogonal frequency division multiplexing
Issue Date:
2006
Publisher:
23rd Biennial Symposium on Communications
Citation:
Volume: 2006, Page : 198-203
Abstract:
Symbol timing and carrier frequency synchronization are crucial to OFDM systems. One of the
blind synchronization methods is the cyclic prefix (CP) based maximum likelihood (ML) symbol timing and
carrier frequency synchronization which correlates the cyclic prefix and the last part of the OFDM symbol.
However, the performance of this method is seriously reduced in the time-variant multipath channel. In this
paper, we propose a new CP which has two parts. One part is a copy of the head of the last symbol and the
other part is a copy of the tail of that symbol. Both parts have the length of half of the CP. As a result of this
new CP, the starting time of one OFDM symbol is allowed to fall into its effective period (the absolute value
of the symbol timing error should be smaller than CP/2). The performance of OFDM systems is improved
significantly with this new CP. ?? 2006 IEEE.
