摘要(英) |
Orthogonal frequency division multiplex, by dividing the bandwidth into multiple orthogonal carriers, is one of the carrier modulation techniques now commonly used in communication system. The orthogonality, however, is impaired by the unsynchronization of the frequency between transmitter and the receiver, which will decrease the efficiency of the system.
The thesis at first introduces the unsynchronization effect in orthogonal frequency division multiplex and how to estimate as well as how to compensate the sampling clock offset. We use the phase errors in automatic gain and carrier recovery to estimate the sampling clock offset resulting in the phase rotation. In the circuit design section, due to the combination of the time domain equalizer and the interpolator circuit, the idle circuit of TEQ can be used as the interpolator circuit to increase the efficiency of the circuit system. |
參考文獻 |
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