发明名称 |
Verfahren und System zur Übertragung und zum Empfang eines digitalen Fernsehsignals mit Verwendung von Mehrträgermodulation |
摘要 |
A method and apparatus for modulating and demodulating an MCM television signal is described which is particularly useful in proposed "simulcast" HDTV terrestrial broadcasting. The MCM spectrum of the television signal is shaped using weighting coefficients which are derived from either an idealized NTSC signal or an actual NTSC co-channel signal. These coefficients are used to shape the respective MCM carriers to provide an energy distribution in the MCM signal which provides greater degree of robustness with a minimum degree of co-channel interference to and from an NTSC co-channel signal. The instant invention further takes advantage of the interference characteristics of composite television signals described above, to position the placement of the MCM carriers in frequency, to minimize interference with an NTSC co-channel signal. Several methods of deriving the weighting coefficients are described including an adaptive approach whereby the characteristics of the interfering NTSC transmission are received and the instantaneous NTSC spectrum calculated therefrom and weighting coefficients assigned accordingly. These coefficients can be transmitted to a receiver to update its coefficient table. |
申请公布号 |
DE69325126(T2) |
申请公布日期 |
1999.11.18 |
申请号 |
DE1993625126T |
申请日期 |
1993.03.11 |
申请人 |
KONINKLIJKE PHILIPS ELECTRONICS N.V., EINDHOVEN |
发明人 |
HULYALKAR, SAMIR N.;BRYAN, DAVID ALAN;BASILE, CARLO |
分类号 |
H04N7/015;H04J11/00;H04L27/26;H04N5/21;H04N5/44;H04N7/08;H04N7/081;H04N7/24;H04N7/26;H04N11/02;H04N11/24;H04N21/2383;H04N21/438;(IPC1-7):H04N7/00 |
主分类号 |
H04N7/015 |
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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