公开(公告)号：US20040240376A1

公开(公告)日：2004-12-02

申请号：US10449992

申请日：2003-05-30

申请人： Agency For Science, Technology and Research

发明人： Zhongjun Wang ,  Lee Guek Yeo ,  Xiaodan Gan

IPC分类号： H04J009/00

CPC分类号： H04L25/022 ,  H04L25/0228 ,  H04L27/265 ,  H04L2025/03414

摘要： A method for channel response estimation for an OFDM communication system based on a certain normal training symbols plus one virtual training symbol begins with receiving at least one preamble symbol of a transmitted data frame. A first channel state information is estimated from the at least one preamble symbol. At least one signalling symbol is then received and equalized and a rate factor and a length factor are extracted from the at least one signalling symbol. A virtual training symbol is formed from the rate factor and the length factor. A second channel state information is estimated from the at least one preamble symbol and the virtual training symbol. The data symbols are equalized by performing channel correction on data symbols with the second channel estimation and pilot sub-carriers in each of the plurality of data symbols.

摘要翻译： 基于某些正常训练符号加上一个虚拟训练符号的OFDM通信系统的信道响应估计方法开始于接收发射数据帧的至少一个前导符号。 从至少一个前导符号估计第一信道状态信息。 然后接收和均衡至少一个信令符号，并且从至少一个信令符号提取速率因子和长度因子。 虚拟训练符号由速率因子和长度因子形成。 从至少一个前导符号和虚拟训练符号估计第二信道状态信息。 通过对数据符号进行信道校正，通过在多个数据符号中的每一个中的第二信道估计和导频子载波来均衡数据符号。

公开(公告)号：US20040202234A1

公开(公告)日：2004-10-14

申请号：US10411211

申请日：2003-04-11

申请人： AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH

发明人： Zhongjun Wang

IPC分类号： H04B001/707

CPC分类号： H04L27/266 ,  H04L27/2659 ,  H04L27/2675

摘要： A receiver is to be synchronized to a transmitter. Two short symbols are sampled in a signal received from the transmitter. The correlation between the two short symbols is determined. The coarse carrier frequency offset of the signal is estimated based on the correlation between the two short symbols. Rather than calculating the phase angle of the correlation between the short symbols, the coarse carrier frequency offset of the signal is determined by dividing the numerical interval of the phase angle of the correlation between the samples of the short symbol into certain equal portions from which their middle values are respectively chosen. Two long symbols in the signal relatively longer in time than the two short symbols are also sampled. The correlation between the two long symbols is determined. A fine carrier frequency offset of the signal is estimated based on the correlation between the two long symbols. A final carrier frequency offset of the received signal is then estimated by combining the estimated coarse and fine carrier frequency offsets prior to correcting the carrier frequency offset of the received signal. The estimated coarse and fine carrier frequency offsets are combined together by adding a multiple of the spacing between carriers forming the signal to the estimated fine carrier frequency offset. The carrier frequency offset of the received signal is corrected using the final carrier frequency offset to synchronize the receiver to the transmitter.

摘要翻译： 接收机将与发射机同步。 在从发射机接收的信号中采样两个短符号。 确定两个短符号之间的相关性。 基于两个短符号之间的相关性来估计信号的粗略载波频率偏移。 不是计算短符号之间的相关的相位角，而是通过将短符号的采样之间的相关角的相位角的数值间隔除以某些相等的部分来确定信号的粗略载波频率偏移， 分别选择中间值。 信号中的两个长符号在时间上比两个短符号相对较长也被采样。 确定两个长符号之间的相关性。 基于两个长符号之间的相关性来估计信号的精细载波频率偏移。 然后，在校正接收信号的载波频率偏移之前，通过组合估计的粗略和精细载波频率偏移来估计接收信号的最终载波频率偏移。 通过将形成信号的载波之间的间隔的倍数与估计的精细载波频率偏移相加来将估计的粗略和精细载波频率偏移组合在一起。 使用最终载波频率偏移校正接收信号的载波频率偏移，以使接收机与发射机同步。