发明授权
- 专利标题: High-data-rate wireless local-area network
- 专利标题(中): 高数据速率无线局域网
-
申请号: US09487395申请日: 2000-01-18
-
公开(公告)号: US06473449B1公开(公告)日: 2002-10-29
- 发明人: John H. Cafarella , Jeffrey H. Fischer
- 申请人: John H. Cafarella , Jeffrey H. Fischer
- 主分类号: H04L2730
- IPC分类号: H04L2730
摘要:
An apparatus and method for communicating data between at least two data devices, suitable for use as a wireless local-area network, that provides robust data communication via a radio communications channel corrupted by multipath interference, particularly at high data rates. A preferred embodiment of the invention represents data as a sequence of Walsh-function waveforms encoded by pseudo-noise direct-sequence spread-spectrum modulation. Walsh-function-encoding of the data provides a long symbol duration, thereby allowing the spread-spectrum modulation to provide processing gain sufficient to substantially overcome multipath interference, while providing a high data rate. In another preferred embodiment, Walsh-function modulation is supplemented with various forms of phase modulation, such as coherent PSK for bi-orthogonal signalling, and DPSK between orthogonal symbols for noncoherent bi-orthogonal signalling, thereby further increasing data rate without reducing processing gain. In another preferred embodiment, Walsh-function modulation is supplemented with spectral shaping to allow increased bandwidth occupancy, thereby further increasing the processing gain without sacrificing data rate.
信息查询