Noise cancelling method and apparatus

Abstract

In a noise canceling method and an apparatus therefor which notices the colored noise looked macroscopically, positively cancels the dominant noise component in the low frequency band, shifts the S/N value to plus, and can extract the reception signal buried in the low frequency band and having a comparatively high level, a signal in which a time axis, an amplitude, and a phase are specified or a zero-point signal is inserted into a transmission signal by an inserter, a noise component is interpolated by using the specified signal or the zero-point signal by a noise canceler, and an originally transmitted signal is regenerated by subtracting the noise component from the reception signal.

1 . A noise canceling method comprising the steps of: 
 periodically inserting a zero-point into a transmission signal,    establishing synchronization based on a received signal,    extracting the zero-point based on the established synchronization and interpolating a noise component of the received signal by using the zero-point, and    subtracting the noise component from the received signal.    
   
   
       2 . The noise canceling method as claimed in  claim 1 , wherein one or more zero-points are inserted at intervals of an integer number of samples.  
   
   
       3 . The noise canceling method as claimed in  claim 2 , wherein an inserted number of the zero-points is determined by deciding a signal quality on the reception side to be notified to the transmission side.  
   
   
       4 . The noise canceling method as claimed in  claim 1  wherein a transmission line of the received signal includes a transparent transmission line.  
   
   
       5 . The noise canceling method as claimed in  claim 4 , wherein the transparent transmission line includes a Nyquist transmission line.  
   
   
       6 . The noise canceling method as claimed in  claim 1  wherein an automatic equalizing process is further performed so as to remove an intersymbol interference at a former or latter stage of a noise cancellation.  
   
   
       7 . A noise canceling apparatus comprising: 
 means periodically inserting a zero-point into a transmission signal,    means establishing synchronization based on a received signal,    means extracting the zero-point based on the established synchronization and interpolating a noise component of the received signal by using the zero-point, and    means subtracting the noise component from the received signal.    
   
   
       8 . The noise canceling apparatus as claimed in  claim 7 , wherein one or more zero-points are inserted at intervals of an integer number of samples.  
   
   
       9 . The noise canceling apparatus as claimed in  claim 8 , wherein an inserted number of the zero-points is determined by deciding a signal quality on the reception side to be notified to the transmission side.  
   
   
       10 . The noise canceling apparatus as claimed in  claim 7  wherein a transmission line of the received signal includes a transparent transmission line.  
   
   
       11 . The noise canceling apparatus as claimed in  claim 10 , wherein the transparent transmission line includes a Nyquist transmission line.  
   
   
       12 . The noise canceling apparatus as claimed in  claim 7  wherein an automatic equalizer is further provided for removing an intersymbol interference at a former or latter stage of a noise cancellation.  
   
   
       13 . A noise canceling method comprising the steps of: 
 receiving a signal periodically including a zero-point,    establishing synchronization based on a received signal,    extracting the zero-point based on the established synchronization,    interpolating a noise component of the received signal by using the zero-point, and    subtracting the noise component from the received signal.    
   
   
       14 . A noise canceling apparatus comprising: 
 means receiving a signal periodically including a zero-point,    means establishing synchronization based on a received signal,    means extracting the zero-point based on the established synchronization,    means interpolating a noise component of the received signal by using the zero-point, and    means subtracting the noise component from the received signal.