Digital broadcast receiving apparatus

Abstract

A digital broadcast receiving apparatus receives a digital broadcast signal, which consists of layers each obtained by dividing a transmission bandwidth into a plurality of segments and combining some of the segments, and outputs images and/or sound from one of the layers constituting the received digital signal. This apparatus is characterized by comprising broadcasting format retention means (channel to broadcasting format correspondence table database) for retaining the broadcasting format, for each layer, of each broadcast station and switching means (layer switching means) for switching the output layer based on the broadcasting format, for each layer, of each broadcast station retained in the broadcasting retention means. Thus, this apparatus can output images and sound without interruption.

What is claimed is:  
     
         1 . A digital broadcast receiving apparatus in which a digital broadcast signal comprising layers each obtained by dividing a transmission bandwidth into a plurality of segments and combining some of the segments is received and images and/or sound are output from one of the layers constituting the received digital signal, said digital broadcast receiving apparatus comprising: 
 broadcasting format retention means for retaining data on a broadcasting format, for each layer, of each broadcast station; and    switching means for switching the output layer based on the broadcasting format, for each layer, of each broadcast station retained by the broadcasting format retention means.    
     
     
         2 . A digital broadcast receiving apparatus according to  claim 1 , further comprising: 
 field strength detection means for detecting a field strength of the received digital broadcast signal and/or reproduction condition detection means for detecting a reproduction condition of each layer of the received digital broadcast signal; and    layer decision means for determining which layer to output based on the detected field strength and/or the reproduction condition.    
     
     
         3 . A digital broadcast receiving apparatus according to  claim 1  or  2  wherein data on a broadcasting format, for each layer, of each broadcast station is obtained through a broadcast or a non-broadcast communication medium.  
     
     
         4 . A digital broadcast receiving apparatus according to  claim 1  or  3 , further comprising history retention means for retaining layer switching records; and 
 communication means;  
 wherein the records retained in the history retention means are transmitted to a digital broadcast fee accounting center via the communication means.  
 
     
     
         5 . A digital broadcast receiving apparatus in which a digital broadcast signal comprising layers each obtained by dividing a transmission bandwidth into a plurality of segments and combining some of the segments is received and at least images are output from one of the layers constituting the received digital signal, said digital broadcast receiving apparatus comprising: 
 broadcasting format retention means for retaining data on a broadcasting format, for each layer, of each broadcast station;    switching means for switching an output layer based on the broadcasting format, for each layer, of each broadcast station retained by the broadcasting format retention means;    field strength detection means for detecting a field strength of the received digital broadcast signal and/or reproduction condition detection means for detecting a reproduction condition of each layer of the received digital broadcast signal;    layer decision means for determining which layer to output based on the detected field strength and/or the reproduction condition; and    setting screen supply means for providing a screen for determining whether the output layer is to be selected based on the detected field strength, the detected reproduction condition, or both the detected field strength and the reproduction condition.    
     
     
         6 . A digital broadcast receiving apparatus according to  claim 5 , further comprising layer information display means for displaying information about the currently output layer in a screen.  
     
     
         7 . A digital broadcast receiving apparatus according to  claim 1  or  6  which is mounted on a movable body.  
     
     
         8 . A digital broadcast receiving method in which a digital broadcast signal comprising layers each obtained by dividing a transmission bandwidth into a plurality of segments and combining some of the segments is received and images and/or sound are output from one of the layers constituting the received digital signal, said digital broadcast receiving method comprising the steps of: 
 detecting a field strength and/or detecting a reproduction condition of each layer of the received digital broadcast signal;    determining which layer to output based on the detected field strength and/or the detected reproduction condition; and    switching the output layer to the determined layer based on a broadcasting format, for each layer, of each broadcast station.    
     
     
         9 . A digital broadcast receiving method according to  claim 8 , further comprising the step of getting the broadcasting format, for each layer, of each broadcast station via a broadcast or a non-broadcast communication medium.