| 摘要 |
Method and apparatus for improving the channel estimate of a communication channel between a first station and a second station, while reducing the amount of reserved bandwidth for pilot tones. Hierarchical modulation is used to augment pilot density without sacrificing throughput. At the first station, a digital information stream may be split into a base stream and an enhancement stream, wherein the base stream and the enhancement stream combined form a hierarchical signal. At the second station, the base stream may be first recovered, and recovered base stream serves as a pilot for the enhancement stream. Thus the base stream, which is a subset of the total transmitted information, may be made to perform the channel-sounding function for the enhancement stream. |
