公开(公告)号：EP1323242A2

公开(公告)日：2003-07-02

申请号：EP01986378.6

申请日：2001-09-25

申请人： Telefonaktiebolaget L M Ericsson (Publ)

发明人： CARLSSON, Torsten ,  GUSTAFSSON, Kjell ,  ATARIUS, Roozbeh ,  ERIKSSON, Haakan ,  ÖSTBERG, Christer ,  PALENIUS, Torgny

IPC分类号： H04B1/707

CPC分类号： H04B1/70758 ,  H04B1/70757 ,  H04B1/712

摘要： A method and system enable matched filters of a CDMA system to be simplified using a two stage search. A course stage and a fine stage jointly produce the locations(s) of received signal path-rays. In a first stage, an oversampled digital signal (240) is decimated, and the decimated signal (415) is applied to a matched filter (420) to eventually produce an approximate location (460). In a second stage, the oversampled signal (240) is shifted based on the determined approximate location (460) and then correlated to a generated code (440), and a more-exact location is selected from the outputs of the correlations (450). Alternatively, a shifted version of the generated code (440) is correlated to the oversampled signal (240), and the more-exact location is selected from the outputs of those correlations (450).