公开(公告)号：US5073906A

公开(公告)日：1991-12-17

申请号：US624201

申请日：1990-12-06

申请人： Susumu Otani ,  Syouji Endo

发明人： Susumu Otani ,  Syouji Endo

IPC分类号： H04L7/08 ,  H04L7/02 ,  H04L7/04

CPC分类号： H04L7/042

摘要： A synchronization (sync) word detection apparatus which, on receiving a signal in which a sync word having a predetermined length (N) is inserted beforehand, detects the sync word out of a demodulated and soft-decided sequence of the received signal. A cross correlator (4) calculates a cross correlation value of the soft-decided and demodulated sequence fed thereto and the sync word. A threshold generating section (1, 2, 3) determines a means power of the demodulated and soft-decided sequence and generates a threshold value on the basis of the mean power. A comparing circuit (5) produces a detection signal when the cross correlation exceeds the threshold value. The apparatus reduces the false detection probability and misdetection prbability even when the receive field intensity sharply changes on a transmission path.