Signal processing apparatus, signal processing method, and reception system

A signal processing method comprising the steps of:

• performing a carrier shift amount detection process, using a signal processing apparatus, for detecting a carrier shift amount constituting a carrier error used for demodulating an orthogonal frequency division multiplexing signal known as the OFDM signal;
• and
• correcting said OFDM signal, using said signal processing apparatus, in accordance with said carrier shift amount;
• wherein
• said OFDM signal includes
• a first preamble signal including subcarriers, and
• a second preamble signal including subcarriers of which the spacing is narrower than the spacing of the subcarriers included in said first preamble signal;
• said second preamble signal includes pilot signals which are known signals located at intervals of a predetermined number of subcarriers;
• and
• said carrier shift amount detection process detects said carrier shift amount using a correlation of said subcarriers included in one such second preamble signal.

A reception system comprising:

• a transmission channel decode processing block configured to perform a transmission channel decoding process on a signal acquired via a transmission channel, said transmission channel decoding process including at least the process of correcting errors having occurred on said transmission channel;
• and
• an information source decode processing block configured to perform an information source decoding process on the signal having undergone said transmission channel decoding process, said information source decoding process including at least the process of expanding compressed information back to the original information;
• wherein
• said signal acquired via said transmission channel is an orthogonal frequency division multiplexing signal known as an OFDM signal obtained by performing at least compression coding for information compression and error correcting coding for correcting the errors having occurred on said transmission channel;
• said transmission channel decode processing block includes
• processing means for performing a carrier shift amount detection process for detecting a carrier shift amount constituting a carrier error used for demodulating said OFDM signal, and
• correction means for correcting said OFDM signal in accordance with said carrier shift amount;
• said OFDM signal includes
• a first preamble signal including subcarriers, and
• a second preamble signal including subcarriers of which the spacing is narrower than the spacing of the subcarriers included in said first preamble signal:
• said second preamble signal includes pilot signals which are known signals located at intervals of a predetermined number of subcarriers;
• and
• said processing means detects said carrier shift amount using a correlation of said subcarriers included in one such second preamble signal.

A reception system comprising:

• a transmission channel decode processing block configured to perform a transmission channel decoding process on a signal acquired via a transmission channel, said transmission channel decoding process including at least the process of correcting errors having occurred on said transmission channel;
• and
• an output block configured to output images and sounds based on the signal having undergone said transmission channel decoding process;
• wherein
• said signal acquired via said transmission channel is an orthogonal frequency division multiplexing signal known as an OFDM signal obtained by performing at least error correcting coding for correcting the errors having occurred on said transmission channel;
• said transmission channel decode processing block includes
• processing means for performing a carrier shift amount detection process for detecting a carrier shift amount constituting a carrier error used for demodulating said OFDM signal, and
• correction means for correcting said OFDM signal in accordance with said carrier shift amount;
• said OFDM signal includes
• a first preamble signal including subcarriers, and
• a second preamble signal including subcarriers of which the spacing is narrower than the spacing of the subcarriers included in said first preamble signal;
• said second preamble signal includes pilot signals which are known signals located at intervals of a predetermined number of subcarriers;
• and
• said processing means detects said carrier shift amount using a correlation of said subcarriers included in one such second preamble signal.

A reception system comprising:

• a transmission channel decode processing block configured to perform a transmission channel decoding process on a signal acquired via a transmission channel, said transmission channel decoding process including at least the process of correcting errors having occurred on said transmission channel;
• and
• a recording block configured to record the signal having undergone said transmission channel decoding process;
• wherein
• said signal acquired via said transmission channel is an orthogonal frequency division multiplexing signal known as an OFDM signal obtained by performing at least error correcting coding for correcting the errors having occurred on said transmission channel;
• said transmission channel decode processing block includes
• processing means for performing a carrier shift amount detection process for detecting a carrier shift amount constituting a carrier error used for demodulating said OFDM signal, and
• correction means for correcting said OFDM signal in accordance with said carrier shift amount;
• said OFDM signal includes
• a first preamble signal including subcarriers, and
• a second preamble signal including subcarriers of which the spacing is narrower than the spacing of the subcarriers included in said first preamble signal;
• said second preamble signal includes pilot signals which are known signals located at intervals of a predetermined number of subcarriers;
• and
• said processing means detects said carrier shift amount using it correlation of said subcarriers included in one such second preamble signal.

A reception system comprising:

• acquisition means for acquiring a signal via a transmission channel;
• and
• a transmission channel decode processing block configured to perform a transmission channel decoding process on the signal acquired via said transmission channel, said transmission channel decoding process including at least the process of correcting errors having occurred on said transmission channel;
• wherein
• said signal acquired via said transmission channel is an orthogonal frequency division multiplexing signal known as an OFDM signal obtained by performing at least error correcting coding for correcting the errors having occurred on said transmission channel;
• said transmission channel decode processing block includes
• processing means for performing a carrier shift amount detection process for detecting a carrier shift amount constituting a carrier error used for demodulating said OFDM signal, and
• correction means for correcting said OFDM signal in accordance with said carrier shift amount;
• said OFDM signal includes
• a first preamble signal including subcarriers, and
• a second preamble signal including subcarriers of which the spacing is narrower than the spacing of the subcarriers included in said first preamble signal;
• said second preamble signal includes pilot signals which are known signals located at intervals of a predetermined number of subcarriers;
• and
• said processing means detects said carrier shift amount using a correlation of said subcarriers included in one such second preamble signal.

A signal processing apparatus comprising:

• a processing block configured to perform a carrier shift amount detection process for detecting a carrier shift amount constituting a carrier error used for demodulating an orthogonal frequency division multiplexing signal known as an OFDM signal;
• and
• a correction block configured to correct said OFDM signal in accordance with said carrier shift amount;
• wherein
• said OFDM signal includes
• a first preamble signal including subcarriers, and
• a second preamble signal including subcarriers of which the spacing is narrower than the spacing of the subcarriers included in said first preamble signal;
• said second preamble signal includes pilot signals which are known signals located at intervals of a predetermined number of subcarriers;
• and
• said processing block detects said carrier shift amount using a correlation of said subcarriers included in one such second preamble signal.