公开(公告)号：CA1165840A

公开(公告)日：1984-04-17

申请号：CA391489

申请日：1981-12-04

Applicant: MOTOROLA INC

Inventor： JASPER STEVEN C ,  JANC ROBERT V ,  ROBINS DAVID S ,  RETZER MICHAEL H

IPC: H04B1/10 ,  C30B29/62 ,  G01R23/02 ,  G01S1/24 ,  G01S5/10 ,  G01R23/00

Abstract: An apparatus and method for determining the period and frequency of a signal interfering with a desired Loran C signal are provided. A sample of the interfering signal is generated at a time corresponding to the peak of the autocorrelation function of the interfering signal with respect to the predetermined pulse tracking reference point of the Loran C signal. Indicia of the period and frequency of the interferer is obtained from the timing of the sample generated at the autocorrelation function peak.

公开(公告)号：CA1165841A

公开(公告)日：1984-04-17

申请号：CA391505

申请日：1981-12-04

Applicant: MOTOROLA INC

Inventor： JASPER STEVEN C ,  JANC ROBERT V ,  ROBINS DAVID S ,  RETZER MICHAEL H

IPC: H04B1/10 ,  G01S1/24 ,  G01S5/10 ,  H04B1/12

Abstract: A method and apparatus for attenuating an interfering signal corrupting a desired Loran C signal is provided. An interfering signal sample is determined which occurs at the peak of the autocorrelation function of the interfering signal such that the period of the interferer is known. The sample occurring at the peak of the autocorrelation function is added to or subtracted from the desired Loran C signal sample taken at a predetermined reference point during the pulses thereof such that the interfering signal is cancelled or substantially attenuated.

公开(公告)号：CA1126865A

公开(公告)日：1982-06-29

申请号：CA332985

申请日：1979-08-01

Applicant: MOTOROLA INC

Inventor： BACKOF CHARLES A JR ,  ROBINS DAVID S

IPC: H04L27/14 ,  G01R23/167 ,  G01R25/00 ,  H03H17/00 ,  H03K9/04 ,  H04L27/00 ,  H04L27/26 ,  H04Q1/457 ,  H04Q9/10

Abstract: PROGRAMMABLE DIGITAL TONE DETECTOR A plurality of up/down counters are controlled by a programmed digital reference signal. The combination of a high select signal and a high input signal causes any one of the counters to increment (up) by one count while a combination of a high select signal and a low input signal causes any one of the counters to decrement (down) one count. A threshold detector signals an output when a specific combination of the counters reaches a predetermined combination count signifying correlation of the programmed reference with the input tone over a predetermined number of cycles. The phase of the input may be determined by noting which of the counters reaches the predetermined threshold.