公开(公告)号：DK110491A

公开(公告)日：1991-06-11

申请号：DK110491

申请日：1991-06-11

Applicant: MOTOROLA INC

Inventor： BORTH DAVID E ,  KEPLER JAMES FRANK M

IPC: H03L7/095 ,  H03J7/02 ,  H03L7/08 ,  H03L7/087

Abstract: There is provided a method of and apparatus for Automatice Frequency Control (AFC) of pure sine waves (PSW). It is characterized by discriminating to detect frequency differences between a received pure sine wave and a reference frequency (20), integrating (30) the frequency differences to average the differences, and adjusting (40) the reference frequency (80) to eliminate the frequency difference. It is further characterized by digitizing, in quadrature, the received pure sine wave (70), mixing (50) the received pure sine wave with a complex sinusoid to translate the pure sine wave to baseband, quadrature filtering (60) the mixed sine wave, cross-product discrimination (20) to detect frequency differences between a received pure sine wave and a reference frequency, integration (30) the frequency differences to average the differences, selectively (100/110) calculating the mean/variance (90) between the pure sine wave and the reference frequency, and adjusting (40) the reference frequency of a Voltage Controlled Oscillator 80 to eliminate the frequency difference.

公开(公告)号：DK110491D0

公开(公告)日：1991-06-11

申请号：DK110491

申请日：1991-06-11

Applicant: MOTOROLA INC

Inventor： BORTH DAVID E ,  KEPLER JAMES FRANK M

IPC: H03L7/095 ,  H03J7/02 ,  H03L7/08 ,  H03L7/087

Abstract: There is provided a method of and apparatus for Automatice Frequency Control (AFC) of pure sine waves (PSW). It is characterized by discriminating to detect frequency differences between a received pure sine wave and a reference frequency (20), integrating (30) the frequency differences to average the differences, and adjusting (40) the reference frequency (80) to eliminate the frequency difference. It is further characterized by digitizing, in quadrature, the received pure sine wave (70), mixing (50) the received pure sine wave with a complex sinusoid to translate the pure sine wave to baseband, quadrature filtering (60) the mixed sine wave, cross-product discrimination (20) to detect frequency differences between a received pure sine wave and a reference frequency, integration (30) the frequency differences to average the differences, selectively (100/110) calculating the mean/variance (90) between the pure sine wave and the reference frequency, and adjusting (40) the reference frequency of a Voltage Controlled Oscillator 80 to eliminate the frequency difference.