Signal processing apparatus and signal processing method

A signal processing apparatus for converting a first digital broadcast having a prescribed transmission frequency on a first network, to a second digital broadcast signal having a prescribed frequency on a second network, characterized by comprising:

• first frequency-converting means for converting the frequency of the first digital broadcast signal, thereby to generate a first digital modulated signal;
• demodulating means for demodulating the first digital modulated signal supplied from the first frequency-converting means, thereby to generate digital broadcast data;
• table-detecting means for detecting a network information table which is physical information about a transmission path, from the digital broadcast data supplied from the demodulating means;
• analyzing means for analyzing information about the first network, on the basis of the network information table detected by the table-detecting means;
• comparing means for comparing the information about the first network analyzed by the analyzing means, with the previous information about the first network;
• table-changing means for changing the network information table of the first network to one that complies with the second network, on the basis of the information about the first network, which has been generated as results of comparison accomplished by the comparing means;
• table-replacing means for replacing the network information table supplied from the demodulating means, with the network information table supplied from the table-changing means;
• modulating means for modulating the digital broadcast data whose network information table has been replaced by the table-replacing means, thereby to generate a second digital modulated signal;
• and
• second frequency-converting means for converting the frequency of the second digital broadcast signal, thereby to generate the second digital broadcast signal.

A signal processing method for converting a first digital broadcast having a prescribed transmission frequency on a first network, to a second digital broadcast signal having a prescribed frequency on a second network, characterized by comprising:

• a first frequency-converting step of converting the frequency of the first digital broadcast signal, thereby to generate a first digital modulated signal;
• a demodulating step of demodulating the first digital modulated signal generated in the first frequency-converting step, thereby to generate digital broadcast data;
• a table-detecting step of detecting a network information table which is physical information about a transmission path, from the digital broadcast data generated in the demodulating step;
• analyzing step of analyzing information about the first network, on the basis of the network information table detected in the table-detecting step;
• comparing step of comparing the information about the first network analyzed by in the analyzing step, with the previous information about the first network;
• table-changing step of changing the network information table of the first network to one that complies with the second network, on the basis of the information about the first network, which has been generated as results of comparison accomplished in the comparing step;
• table-replacing step of replacing the network information table generated in the demodulating step, with the network information table generated in the table-changing step;
• modulating step of modulating the digital broadcast data whose network information table has been replaced in the table-replacing step, thereby to generate a second digital modulated signal;
• and
• second frequency-converting step for converting the frequency of the second digital broadcast signal, thereby to generate the second digital broadcast signal.