发明名称 |
Mitigation of co-channel interference in synchronization bursts in a multi-beam communication system |
摘要 |
<p>In a cellular satellite system such as Astrolink, where same frequency, same polarization (same "color") signals are used in multiple ground cells, there exists the possibility of interference and false reception of uplink Synchronization Bursts (SB) in systems employing TDMA access of the frequency in question. In such systems, a SB transmitted from one terminal may be received in more than one satellite beam. The reception of the signal from a terminal in an undesired beam (330) is erroneous and may adversely impact the time synchronization (360) of the desired terminal. For example, a system may employ Maximal Length (ML) Pseudo-Noise (PN) sequences (410) for its SBs wherein every beam may use the same sequence. To minimize false reception, the ML PN sequences (410) of each SB may be cyclicly shifted a different amount for each beam to generate sequences (410, 420) having low corsscorrelation with each other. By choosing ML PN codes having low crosscorrelation (410, 420) for the different beams, the interference from undesired beams may be minimized (530).</p> |
申请公布号 |
EP1059738(A2) |
申请公布日期 |
2000.12.13 |
申请号 |
EP20000111814 |
申请日期 |
2000.06.06 |
申请人 |
NORTHROP GRUMMAN CORPORATION |
发明人 |
LINSKY, STUART, T.;CASO, GREGORY, S.;WRIGHT, DAVID, A. |
分类号 |
H04L27/20;H04B7/185;H04B7/212;H04J3/00;H04L7/00;H04L27/36;(IPC1-7):H04B7/185 |
主分类号 |
H04L27/20 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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