There are many key technologies about the single-user detection, such as synchronization between receiver and transmitter, channel estimation and diversity.
单用户检测中的关键技术很多，主要有接收端和发送端的同步，信道估计和分集等。
2
The synchronization word re occurs once again after the last channel has been received.
当最后一个话路的码字收到之后，同步码又再次出现。
3
Synchronization and channel estimation are two key techniques for OFDM systems to ensure its good performance.