发明名称 |
METHOD AND CIRCUIT ARRANGEMENT FOR IMPROVING CARRIER SEPARATION FOR THE TRANSMISSION OF OFDM SIGNALS |
摘要 |
In the OFDM methods, a plurality of modulated carriers are transmitted by frequency multiplexing, which results in an almost rectangular spectrum owing to the high number of carriers. In order to separate the carriers from one another again in the receiver, a fast Fourier transform is carried out such that each carrier can be cleanly separated from the others when the carriers are exactly orthogonal relative to one another. However, the orthogonality of the carriers can be disturbed by various causes. Furthermore, in the receiver the useful signal has to be separated from the undesired neighbouring channel signals by analog or digital filtration. In order to improve carrier and channel separation, the selectivity of FFT filtration can be increased by increasing the number of FFT components. However, this normally leads to an undesirably high increase in computing steps. The claimed configuration of the time window used within the context of the FTT and oversampling before the FFT render the calculation of some of the coefficients superfluous.
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申请公布号 |
WO9641458(A1) |
申请公布日期 |
1996.12.19 |
申请号 |
WO1996EP02209 |
申请日期 |
1996.05.23 |
申请人 |
DEUTSCHE THOMSON-BRANDT GMBH;MUSCHALLIK, CLAUS;ARMBRUSTER, VEIT |
发明人 |
MUSCHALLIK, CLAUS;ARMBRUSTER, VEIT |
分类号 |
H04J11/00;H04L27/26;(IPC1-7):H04L27/26;H04L5/06 |
主分类号 |
H04J11/00 |
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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