发明名称 |
Carrier and symbol synchronisation for 8-DPSK signals |
摘要 |
<p>A radio receiver (10) processes a carrier signal having a Doppler shifted frequency and carrying a coded signal having variable phase and amplitude. The coded signal is divided into a preamble portion and a message portion. A memory (23) stores samples of the coded signal representing at least some of the predetermined symbols of the preamble. A logic unit (16) divides the stored samples into a plurality of sample groups and identifies one sample group having the minimum variation of envelope amplitude. That sample group is used to provide additional samples by which the Doppler shift of the carrier frequency is estimated (70). The coded signal is delayed by a delay operation (100) and has its Doppler shift reduced. The Doppler reduced coded signal is processed by a filter operation (120) and a demodulator (130). <IMAGE></p> |
申请公布号 |
EP1128621(A2) |
申请公布日期 |
2001.08.29 |
申请号 |
EP20010102125 |
申请日期 |
2001.01.31 |
申请人 |
NORTHROP GRUMMAN CORPORATION |
发明人 |
MYERS, MICHAEL H. |
分类号 |
H04L27/00;H04L27/233;(IPC1-7):H04L27/233;H04L7/04 |
主分类号 |
H04L27/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|