公开(公告)号：EP1949636B1

公开(公告)日：2018-07-25

申请号：EP06839907.0

申请日：2006-11-15

申请人： QUALCOMM Incorporated

发明人： GLAZKO, Serguei A. ,  LAI, Kuei-chiang ,  PATEL, Shimman

IPC分类号： H04L27/26

CPC分类号： H04L27/2665 ,  H04L27/2678 ,  H04L27/2688 ,  H04L27/2695

摘要： Techniques for performing time tracking at a receiver are described. A first arriving path (FAP) and a last arriving path (LAP) are detected based on a channel impulse response estimate for a communication channel. The detected FAP and LAP may be correct or swapped. To resolve ambiguity in the detected FAP and LAP, a first hypothesis corresponding to the FAP and LAP being correctly detected and a second hypothesis corresponding to the FAP and LAP being incorrectly detected are evaluated. For each hypothesis, hypothesized FAP and LAP are determined based on the detected FAP and LAP, a correlation window is determined based on the hypothesized FAP and LAP, and correlation is performed using the correlation window. The correct hypothesis is determined based on correlation results for the two hypotheses. The receiver timing is updated based on the hypothesized FAP and LAP for the correct hypothesis and used for demodulation.

公开(公告)号：EP1999922A2

公开(公告)日：2008-12-10

申请号：EP06850959.5

申请日：2006-12-14

申请人： Qualcomm Incorporated

发明人： PATEL, Shimman ,  LAI, Kuei-chiang ,  GLAZKO, Serguei A.

IPC分类号： H04L27/26

CPC分类号： H04L27/2695 ,  H04L5/0048 ,  H04L25/022 ,  H04L25/0228 ,  H04L27/2613 ,  H04L27/2659 ,  H04L27/2662 ,  H04L27/3872 ,  H04L2027/0034 ,  H04L2027/0065

摘要： For frequency bin error estimation, multiple hypotheses are formed for different frequency bin errors, pilot offsets, or combinations of frequency bin error and pilot offset. For each hypothesis, received symbols are extracted from the proper subbands determined by the hypothesis. In one scheme, the extracted received symbols for each hypothesis are despread with a scrambling sequence to obtain despread symbols for that hypothesis. A metric is derived for each hypothesis based on the despread symbols, e.g., by deriving a channel impulse response estimate based on the despread symbols and then deriving the metric based on the channel impulse response estimate. In another scheme, the extracted received symbols for each hypothesis are correlated, and a metric is derived based on the correlation results. For both schemes, the frequency bin error and/or the pilot offset are determined based on the metrics for all hypotheses evaluated.

公开(公告)号：EP1949636A1

公开(公告)日：2008-07-30

申请号：EP06839907.0

申请日：2006-11-15

申请人： QUALCOMM Incorporated

发明人： GLAZKO, Serguei A. ,  LAI, Kuei-chiang ,  PATEL, Shimman

IPC分类号： H04L27/26

CPC分类号： H04L27/2665 ,  H04L27/2678 ,  H04L27/2688 ,  H04L27/2695

摘要： Techniques for performing time tracking at a receiver are described. A first arriving path (FAP) and a last arriving path (LAP) are detected based on a channel impulse response estimate for a communication channel. The detected FAP and LAP may be correct or swapped. To resolve ambiguity in the detected FAP and LAP, a first hypothesis corresponding to the FAP and LAP being correctly detected and a second hypothesis corresponding to the FAP and LAP being incorrectly detected are evaluated. For each hypothesis, hypothesized FAP and LAP are determined based on the detected FAP and LAP, a correlation window is determined based on the hypothesized FAP and LAP, and correlation is performed using the correlation window. The correct hypothesis is determined based on correlation results for the two hypotheses. The receiver timing is updated based on the hypothesized FAP and LAP for the correct hypothesis and used for demodulation.