David Bryan

US Patent:

52820190, Jan 25, 1994

Filed:

Apr 29, 1992

Appl. No.:

7/875491

Inventors:

Carlo Basile - Ossining NY
Aldo G. Cugnini - Tarrytown NY
Alan P. Cavallerano - Ossining NY
David A. Bryan - Danbury CT
Faramarz Azadegan - Brookfield CT
Mikhail Tsinberg - Riverdale NY

International Classification:

H04N 1112
H04N 706

US Classification:

358 12

Abstract:

A method and apparatus for encoding a television source signal having a first bandwidth, into a frequency multiplexed signal having a narrower bandwidth and comprising a plurality of subcarriers modulated with digital information. Each of said subcarriers has an amplitude, bandwidth and coding characteristic which reflects the relative importance of the digital information provided thereby. The frequency multiplexed signal is suitable for use in a broadcasting environment wherein a conventional television signal is also used and wherein said subcarriers are disposed in frequency, in positions which are least likely to result in interference to or from said conventional signal. The invention also includes a receiver for decoding the frequency multiplexed signal and for providing a high definition display.

US Patent:

52912892, Mar 1, 1994

Filed:

Mar 20, 1992

Appl. No.:

7/854177

Inventors:

Samir N. Hulyalkar - Ossining NY
David A. Bryan - Danbury CT
Carlo Basile - Ossining NY

Assignee:

North American Philips Corporation - New York NY

International Classification:

H04N 540
H04N 706
H04L 512
H04L 2302

US Classification:

348723

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.

US Patent:

51344645, Jul 28, 1992

Filed:

Jan 29, 1991

Appl. No.:

7/647383

Inventors:

Carlo Basile - Ossining NY
Aldo G. Cugnini - Tarrytown NY
Alan P. Cavallerano - Ossining NY
David A. Bryan - Danbury CT
Faramarz Azadegan - Brookfield CT
Mikhail Tsinberg - Riverdale NY

Assignee:

North American Philips Corporation - New York NY

International Classification:

H04N 1112
H04N 706

US Classification:

358 12

Abstract:

A method and apparatus for encoding a television source signal having a first bandwidth, into a frequency multiplexed signal having a narrower bandwidth and comprising a plurality of subcarriers modulated with digital information. Each of said subcarriers has an amplitude, bandwidth and coding characteristic which reflects the relative importance of the digital information provided thereby. The frequency multiplexed signal is suitable for use in a broadcasting environment wherein a conventional television signal is also used and wherein said subcarriers are disposed in frequency, in positions which are least likely to result in interference to or from said conventional signal. The invention also includes a receiver for decoding the frequency multiplexed signal and for providing a high definition display.