公开(公告)号：FR2599574B1

公开(公告)日：1990-08-31

申请号：FR8707518

申请日：1987-05-27

Applicant: RCA CORP

Inventor： CAMPBELL EDWARD RICHARD III ,  LEWIS HENRY GARTON JR

IPC: H03D3/00 ,  H04N5/21 ,  H04N5/455

Abstract: In a television receiver including an automatic deghosting system 24, Fig. 1 (634, Fig. 6) means 18, 22 are provided for synchronously demodulating IF television signals to generate baseband signals representing the in phase (I) and quadrature phase (Q) modulation components of the IF signals. A carrier signal extractor circuit 14 extracts the received carrier signal from the radio frequency television signal. A phase locked loop 16 coupled to the carrier signal extracting circuit generates a phase difference signal representing the difference in phase between the oscillatory and the extracted carrier signals. A demodulation phase error detector 26, (630) coupled to the synchronous demodulation means generates a phase control signal proportional to the difference in phase between the direct carrier signal as broadcast and the received carrier signal which may include ghosts. A phase correction circuit 312, 316, 318, Fig. 3 or a ROM (632, Fig. 6) responds to the phase control signal and modifies the phase difference signal (or the first baseband signal) to generate a modified first baseband signal with substantially reduced crosstalk distortion components.

公开(公告)号：FR2599574A1

公开(公告)日：1987-12-04

申请号：FR8707518

申请日：1987-05-27

Applicant: RCA CORP

Inventor： CAMPBELL EDWARD RICHARD III ,  LEWIS HENRY GARTON JR

IPC: H03D3/00 ,  H04N5/21 ,  H04N5/455

Abstract: In a television receiver including an automatic deghosting system 24, Fig. 1 (634, Fig. 6) means 18, 22 are provided for synchronously demodulating IF television signals to generate baseband signals representing the in phase (I) and quadrature phase (Q) modulation components of the IF signals. A carrier signal extractor circuit 14 extracts the received carrier signal from the radio frequency television signal. A phase locked loop 16 coupled to the carrier signal extracting circuit generates a phase difference signal representing the difference in phase between the oscillatory and the extracted carrier signals. A demodulation phase error detector 26, (630) coupled to the synchronous demodulation means generates a phase control signal proportional to the difference in phase between the direct carrier signal as broadcast and the received carrier signal which may include ghosts. A phase correction circuit 312, 316, 318, Fig. 3 or a ROM (632, Fig. 6) responds to the phase control signal and modifies the phase difference signal (or the first baseband signal) to generate a modified first baseband signal with substantially reduced crosstalk distortion components.