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：NO905055A

公开(公告)日：1990-11-22

申请号：NO905055

申请日：1990-11-22

Applicant: MOTOROLA INC

Inventor： BORTH DAVID E ,  KEPLER JAMES F

IPC: H04L27/38 ,  H03J7/02 ,  H03L20060101 ,  H03L7/00 ,  H03L7/087 ,  H04B7/26 ,  H04L27/00 ,  H04L27/227

CPC classification number: H03J7/02 ,  H03L7/087 ,  H04B7/2643 ,  H04L27/2273 ,  H04L2027/0057 ,  H04L2027/0065

公开(公告)号：AU5161190A

公开(公告)日：1990-11-05

申请号：AU5161190

申请日：1990-02-20

Applicant: MOTOROLA INC

Inventor： BORTH DAVID E ,  KEPLER JAMES F

IPC: H04L27/38 ,  H03J7/02 ,  H03L20060101 ,  H03L7/00 ,  H03L7/087 ,  H04B7/26 ,  H04L27/00 ,  H04L27/227

Abstract: A frequency control apparatus for a burst-mode radio communications system (TDMA) employing a frequency correction signal transmitted as a burst to enable correction of frequency differences between the frequency of the radio carrier of a subsequent communication burst and the frequency of reception by a radio receiver, the frequency control apparatus including a variable frequency oscillator (115), for receiving a frequency correction signal burst and a digital signal processor (111) for processing a communication burst having a frequency difference between said variable frequency oscillator and the radio carrier frequency of said communication burst and for generating a singular control signal value and for applying said singular control signal value to said variable frequency oscillator (115), via an A/D converter, to correct said frequency difference.

公开(公告)号：CA1264356A

公开(公告)日：1990-01-09

申请号：CA533558

申请日：1987-04-01

Applicant: MOTOROLA INC

Inventor： BORTH DAVID E ,  GERSON IRA A ,  VILMUR RICHARD J

IPC: H04B1/40

Abstract: of the Invention An improved hands-free user-interactive control and dialing system is disclosed for use with a speech communications device. The control system (400) includes a dynamic noise suppressor (410), a speech recognizer (420) for implementing voice-control, a device controller (430) responsive to the speech recognizer for controlling operating parameters of the speech communications device (450) and for producing status information representing the operating status of the device, and a speech synthesizer (440) for providing reply information to the user as to the speech communications device operating status. In a mobile radiotelephone application, the spectral subtraction noise suppressor (414) is configured to improve the performance of the speech recognizer (424), the voice quality of the transmitted audio (417), and the audio switching operation of the vehicular speakerphone (460). The combination of noise processing, speech recognition, and speech synthesis provides a substantial improvement to prior art control systems.