发明名称 |
Arrangement for synchronizing access points in WLAN using direct-sequence spread spectrum signaling |
摘要 |
An arrangement for providing synchronization between a number of overlapping area access points within a wireless LAN utilizes a Power over Ethernet (PoE) cable connection to transmit synchronization signals from a centralized hub/switch to each of the access points connected to the cable. The synchronization signal takes the form of a direct sequence spread spectrum (DS-SS) signal that is coupled onto the twisted pair used to provide the low voltage PoE signal to various powered devices. At each access point, a filter is used to remove the synchronization signal from the PoE transport, allowing for the group of access points to share a common beacon signal and allow for frequency re-use among the access points. The DS-SS signal is preferable created by a combination of a baseband signal and a set of separate pseudo noise (PN) sequences defining a precision phase ("pilot tone") signal, a time mark (superframe/beacon) signal, and a time-of-day (real-time clock) signal. |
申请公布号 |
US7656855(B2) |
申请公布日期 |
2010.02.02 |
申请号 |
US20060505553 |
申请日期 |
2006.08.16 |
申请人 |
AT&T INTELLECTUAL PROPERTY II, LP |
发明人 |
GHASSEMZADEH SAEED S.;MILLER, II ROBERT RAYMOND;MURRAY JOHN F. |
分类号 |
H04J3/06 |
主分类号 |
H04J3/06 |
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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