Pulse or digital communications – Systems using alternating or pulsating current
Reexamination Certificate
2005-05-24
2005-05-24
Liu, Shuwang (Department: 2634)
Pulse or digital communications
Systems using alternating or pulsating current
C375S265000, C375S260000, C375S295000, C375S316000
Reexamination Certificate
active
06898249
ABSTRACT:
A method of in-band on-channel (IBOC) digital audio broadcasting (DAB) comprises the steps of providing an analog modulated carrier signal in a central frequency band of an AM radio channel, providing a first plurality of subcarriers in an upper sideband of the AM radio channel, providing a second plurality of subcarriers in a lower sideband of the AM radio channel, providing a third plurality of subcarriers in the central frequency band of the AM radio channel, modulating the first, second and third plurality of subcarriers with one or more digitally encoded signals, and transmitting the analog modulated signal and the first, second and third plurality of subcarriers, wherein the subcarriers in the third plurality of subcarriers that are positioned closest to the center of the channel are transmitted at higher power spectral densities than the subcarriers in the third plurality of subcarriers that are positioned farther from the center of the channel. The power spectral densities of a first group of the subcarriers in the third plurality of subcarriers can decrease linearly with frequency separation from the center of the channel. Transmitters and receivers that utilize the composite IBOC DAB signal are also included.
REFERENCES:
patent: 5588022 (1996-12-01), Dapper et al.
patent: 5606576 (1997-02-01), Dapper et al.
patent: 5859876 (1999-01-01), Dapper et al.
patent: 5898732 (1999-04-01), Dapper et al.
patent: 5930687 (1999-07-01), Dapper et al.
patent: 6005894 (1999-12-01), Kumar
patent: 6178317 (2001-01-01), Kroeger et al.
patent: 6243424 (2001-06-01), Kroeger et al.
patent: 6292511 (2001-09-01), Goldston et al.
patent: 6295317 (2001-09-01), Hartup et al.
patent: 6351500 (2002-02-01), Kumar
patent: 6400758 (2002-06-01), Goldston et al.
patent: 6445750 (2002-09-01), Chen et al.
patent: 6452977 (2002-09-01), Goldston et al.
patent: 6487256 (2002-11-01), Kroeger et al.
patent: 6549544 (2003-04-01), Kroeger et al.
patent: 20010024475 (2001-09-01), Kumar
patent: 20040022229 (2004-02-01), Vanness
“System for Digital Sound Broadcasting in the Broadcasting Bands Below 30 MHz,” Draft New Recommendation ITU-R BS, International Telecommunication Union, Radiocommunication Study Groups, Oct. 25, 2000, pp. 1-30.
IBOC AM Transmission Specification, Nov. 2001, pp. 1-28.
Johnson Steven Andrew
Kroeger Brian William
iBiquity Digital Corporation
Lenart, Esq. Robert P.
Liu Shuwang
Pietragallo Bosick & Gordon
Zheng Eva
LandOfFree
Method and apparatus for AM digital audio broadcasting with... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for AM digital audio broadcasting with..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for AM digital audio broadcasting with... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3405140