Television – Television transmitter circuitry
Patent
1992-03-20
1994-03-01
Powell, Mark R.
Television
Television transmitter circuitry
375 39, 375 42, 348469, 348473, H04N 540, H04N 706, H04L 512, H04L 2302
Patent
active
052912892
ABSTRACT:
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.
REFERENCES:
patent: 4780884 (1988-10-01), Karabinis
patent: 5022053 (1991-06-01), Chung et al.
patent: 5056117 (1991-10-01), Gitlin et al.
patent: 5057786 (1991-10-01), Yoshikawa
patent: 5113142 (1992-05-01), Yoshikawa
patent: 5113412 (1992-05-01), Goldstein
patent: 5127021 (1992-06-01), Schreiber
patent: 5134464 (1992-07-01), Basile et al.
"A Bandwidth Allocation Strategy For A FDM Multicarrier Modem", R. L. Cupo, IEEE Trans-Commun., vol. 39, No. 5, May 91, pp. 644-646.
Basile Carlo
Bryan David A.
Hulyalkar Samir N.
Marion Michael E.
Miller John W.
North American Philips Corporation
Powell Mark R.
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