Rca Thomson Licensing Corp.

Rca Inc.

Rca Licensing Corporation

Edward R Campbell, Iii

Donald J Sauer

William E Rodda

Henry G Lewis, Jr

Michael Anthony Isnardi

Joshua Lawrence Koslov

Robert E Flory

Francis Dell'Ova

Tzy-Hong S Chao

Phase lock loop with idle mode of operation during vertical blanking

Oscillator with switched reactive elements

Phase lock loop with error consistency detector

Phase lock loop with error measurement and correction in alternate

A television signal ghost cancellation system is described in which a microprocessor is used to develop a mathematical model of the transmission channel which produced a ghosted video signal. The microprocessor determines the coefficient values and delay values for a digital IIR filter from this model. The system uses the IIR filter to cancel ghost signals from the ghosted video signal. The IIR filter includes circuitry for interpolating between successively delayed sample values to cancel ghost signals which are delayed by a non-integer number of sample periods.

Adaptive television ghost cancellation system including filter circuitry

A system is disclosed for partially decoding an encoded widescreen, extended definition television signal into a signal that is compatible with existing consumer video cassette recorders (VCRs) and video monitors. The encoded signal is compatible with existing television standards to produce a video image having a conventional 4:3 aspect ratio. Signals representing side panel information, to be appended onto either side of the 4:3 center panel, are encoded in the signal and are not visible in the image produced by a conventional receiver. The disclosed system includes decoding circuitry which recovers the side panel signals, appends them to the center panel signal and changes the time correspondence of the total signal so that it represents an image having a 5:3 aspect ratio. Luminance and chrominance components of the decoded video signal are provided as output signals of the decoder and to input ports of a conventional video cassette recorder (VCR) such as an S-VHS or ED-Beta machine. The signal recorded on the VCR may be replayed on a widescreen monitor. The decoder includes an optional vertical interpolator to compress the widescreen picture vertically to generate a signal which produces a properly proportioned widescreen image when displayed on a conventional display device.

Widescreen television reception and recording system utilizing

A television receiver which includes an automatic deghosting system synchronously demodulates IF television signals to generate baseband signals representing the in-phase and quadrature phase modulation components of the IF signals. A signal representing the phase difference between the carrier of the signal as broadcast and the carrier of the received signal, which may include ghosts, is generated from the in-phase and quadrature signals. This signal is applied to circuitry which develops signals proportional to the sine and cosine of the phase angle separating the broadcast carrier phase and the received carrier phase. The demodulated in-phase and quadrature phase baseband signals are multiplied by the sine and cosine signals in a complex multiplier to correct distortion resulting from the synchronous demodulation using the carrier of the received signal.

Demodulation phase error compensation circuitry as for an automatic

An automatic deghosting system synchronously demodulates IF television signals to generate baseband composite video signals. A strong RF ghost signal having a carrier phase that differs from that of the desired signal may cause demodulation phase errors, causing quadrature distortion in the baseband video signals. The circuitry shown in this disclosure synchronously demodulates the quadrature component of the IF television signals and develops a signal proportional to the difference between the values of the baseband quadrature signal immediately before and immediately after the leading edge of the vertical sync pulse. This signal, which is proportional to the demodulation phase error, is used to control a phase locked loop that regenerates the in-phase and quadrature carrier signals used by the synchronous demodulators to substantially eliminate any demodulation phase error.

Circuitry for reducing demodulation phase error as for an automatic

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Tabernacle, NJ, United States of America

Edward R Campbell, Iii