Method and apparatus for combating co-channel NTSC interference for digital TV transmission

Patent 5512957 Issued on April 30, 1996. Estimated Expiration Date:

April 20, 2014. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3652992

Coded modulation system using interleaving for decision-feedback equalization
Patent #: 4833693
Issued on: 05/23/1989
Inventor: Eyuboglu

Multi-rate voice encoding method and device
Patent #: 4965789
Issued on: 10/23/1990
Inventor: Bottau, et al.

Co-channel interference reduction system for digital high definition television
Patent #: 5086340
Issued on: 02/04/1992
Inventor: Citta, et al.

VSB HDTV transmission system with reduced NTSC co-channel interference
Patent #: 5087975
Issued on: 02/11/1992
Inventor: Citta, et al.

HDTV transmission system with reduced NTSC CO-channel interference
Patent #: 5121203
Issued on: 06/09/1992
Inventor: Citta

Television signal transmission system with carrier offset compensation
Patent #: 5181112
Issued on: 01/19/1993
Inventor: Citta, et al.

Apparatus for NTSC signal interference cancellation through the use of digital recursive notch filters
Patent #: 5325188
Issued on: 06/28/1994
Inventor: Scarpa

Generalized viterbi algorithm with tail-biting Patent #: 5349589
Issued on: 09/20/1994
Inventor: Chennakeshu, et al.

Inventor

Hulyalkar, Samir N.

Application

No. 230360 filed on 04/20/1994

US Classes:

348/607, Noise or undesired signal reduction348/21, PLURAL TRANSMITTER SYSTEM CONSIDERATIONS (E.G., INTERFERENCE REDUCTION)375/350, By filtering (e.g., digital)455/296Noise or interference elimination

Examiners

Primary: Groody, James J.
Assistant: Murrell, Jeffrey S.

Attorney, Agent or Firm

Marion; Michael E.

International Class

H04N 005/455

Abstract

An ATV receiver having a decoder which is designed to process a subset limited trellis pre-coded television signal. The decoder processes co-channel interference so as to produce at the filter output of a rejection filter, a residual interference spectrum which is as flat as possible. The filter exploits the fact that only the picture and the sound carriers need to be sufficiently attenuated and cancels NTSC co-channel interference with only a small degradation in performance when AWGN is also present.

Other References

Eyuboglu et al., "Trellis Precoding: Combined Coding, Precoding and Shaping for Intersymbol Interference Channels", IEEE Trans. on Info. Theory, vol. 38, No. 3, Mar. 1992, pp. 301-314
Forney, "Trellis Shaping", IEEE Trans. on Info. Theory, vol. 38, No. 2, Mar. 1992, pp. 281-300
Heegard et al., "Practical Coding for QAM Transmission of HDTV", IEEE Journal on Selected Areas in Comm., vol. 11, No. 1, Jan. 1993, pp. 111-118
Ungerboeck, "Channel Coding with Multilevel/Phase Signals", IEEE Trans. on Info. Theory, vol. IT-28, No. 1, Jan. 1982, pp. 55-67
Wei, "Precoding Technique for Partial-Response Channels with Applicaiotns to HDTV Transmission", IEEE Journal on Selected Areas in Comm., vol. 11, No. 1, Jan. 1993, pp. 127-135
Eyuboglu, "Detection of Coded Modulation Signals on Linear, Severly Distorted Channels Using Decision-Feedback Noise Prediction with Interleaving", IEEE Trans. on Comm., vol. 36, No. 4, Apr. 1988, pp. 401-409
Tomlinson, "New Automatic Equaliser Employing Modulo Arithmetic", Electronics Letters, Mar. 25, 1971, vol. 7, Nos. 5/6, pp. 138-139
Harashima et al., "Matched-Transmission Technique for Channels With Inter-symbol Interference", IEEE Trans. on Comm., vol. COM-20, No. 4, Aug. 1972, pp. 774-779
"Advanced Digital Television: System Description", Jan. 20, 1992, Philips Laboratories
"VSB Transmission System Zenith Electronics Corporation", Dec. 17, 1993, Technical Details
"Technical Details--Digital Spectrum Compatible", Zenith, Sep. 23, 1991
"Summary Description of Terrestrial and Cable Bakeoff Systems", General Instruments, Jan. 17, 1994
"Digicipher HDTV System Description", General Instrument Corporation, Aug. 22, 1991
"Channel Compatible Digicipher HDTV System", Massachusetts Institute of Technology, Apr. 3, 199