Transmission device, reception device and radio communication method

A receiving apparatus comprising:

• a reception section that receives a multiplex signal wherein a first modulated signal in which an information signal is digitally modulated and a second modulated signal in which a preset signal sequence is digitally modulated are multiplexed in a same frequency band;
• a synchronization section that acquires time synchronization with a transmitting apparatus using said second modulated signal;
• and
• a demodulation section that demodulates said first modulated signal from said multiplex signal using synchronization information obtained by said synchronization section.

A transmitting apparatus comprising:

• a first modulation section that digitally modulates an information signal and obtains a first modulated signal;
• a second modulation section that digitally modulates an information signal by means of a spread spectrum system and obtains a second modulated signal;
• a multiplexing section that multiplexes said first modulated signal and second modulated signal in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which a first modulated signal in which an information signal is digitally modulated and a second modulated signal in which an information signal is spread spectrum modulated are multiplexed in a same frequency band;
• a spread spectrum demodulation section that obtains a second modulated signal demodulated signal from said multiplex signal by despreading said second modulated signal;
• a spread spectrum modulated signal regeneration section that forms a replica signal of said second modulated signal by executing spreading processing on a signal obtained by said spread spectrum demodulation section;
• a signal elimination section that extracts said first modulated signal by eliminating said second modulated signal replica signal from said multiplex signal;
• and
• a demodulation section that demodulates extracted said first modulated signal.

A transmitting apparatus comprising:

• a modulation section that digitally modulates an information signal and obtains a modulated signal;
• a selection section that selects a signal corresponding to an information signal from a plurality of specific modulated signals;
• a multiplexing section that multiplexes said modulated signal and said specific modulated signal selected by said selection section in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which a modulated signal in which an information signal is digitally modulated and a specific modulated signal selected as corresponding to said information signal are multiplexed in a same frequency band;
• a specific modulated signal estimation section that estimates a specific modulated signal contained in said multiplex signal and outputs an information signal corresponding to that specific modulated signal;
• a signal elimination section that extracts said modulated signal within said multiplex signal by eliminating said estimated specific modulated signal from said multiplex signal;
• and
• a demodulation section that demodulates extracted said modulated signal.

A transmitting apparatus comprising:

• a first modulation section that digitally modulates an information signal and obtains a first modulated signal;
• a second modulation section that modulates an information signal using a spread spectrum system and obtains a second modulated signal;
• a multiplexing section that multiplexes said first modulated signal and second modulated signal in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal;
• wherein said first and second modulation sections perform modulation processing so that signal points of said first modulated signal and said second modulated signal are arranged at different positions in an in-phase-quadrature plane.

A transmitting apparatus comprising:

• a first modulation section that digitally modulates an information signal and obtains a first modulated signal;
• a second modulation section that modulates an information signal using a spread spectrum system and obtains a second modulated signal:
• a multiplexing section that multiplexes said first modulated signal and second modulated signal in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal;
• wherein:
• said second modulation section forms a plurality of spread information signals as said second modulated signals by performing spreading processing on signals subject to spreading using different spreading codes;
• and
• said multiplexing section multiplexes multiplex frame information and/or spreading code information together with said multiplex signal.

A transmitting apparatus comprising:

• a first modulation section that digitally modulates an information signal and obtains a first modulated signal;
• a second modulation section that forms a plurality of specific modulated signals modulated in a specific known arrangement decided beforehand with a receiving side;
• a selection section that selects a signal corresponding to said information signal from among said plurality of specific modulated signals;
• a multiplexing section that multiplexes said first modulated signal and a specific modulated signal selected by said selection section in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal;
• wherein said first and second modulation sections perform modulation processing so that signal points of said first modulated signal and said specific modulated signal are arranged at different positions in an in-phase-quadrature plane.

A transmitting apparatus comprising:

• an OFDM modulation section that executes orthogonal frequency division multiplexing processing on an information signal and obtains an OFDM modulated signal;
• an OFDM-spreading modulation section that executes spreading processing and orthogonal frequency division multiplexing processing on an information signal and obtains an OFDM-spreading modulated signal;
• a multiplexing section that multiplexes said OFDM modulated signal and said OFDM-spreading modulated signal in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which a first modulated signal in which an information signal is digitally modulated and a second modulated signal in which an information signal is modulated using a spread spectrum system and whose signal points are arranged at different positions from those of said first modulated signal in an in-phase-quadrature plane are multiplexed in a same frequency band;
• a despreading and demodulation section that despreads a received multiplex signal and also demodulates said second modulated signal taking account of a signal point arrangement at the time of modulation;
• a regeneration section that regenerates a second modulated signal from a demodulated signal and forms a replica signal of said second modulated signal;
• a signal elimination section that extracts said first modulated signal by eliminating said replica signal from said received multiplex signal;
• and
• a demodulation section that demodulates extracted said first modulated signal taking account of signal point arrangement at the time of modulation.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which a first modulated signal in which an information signal is digitally modulated and a second modulated signal formed by performing spreading processing on information signals subject to spreading using different spreading codes are multiplexed in a same frequency band, and multiplex frame information and/or spreading code information;
• a despreading and demodulation section that despreads a received multiplex signal using different spreading codes and demodulates each spread information signal;
• a regeneration section that forms a replica signal of a second modulated signal by regenerating a second modulated signal from each demodulated information signal;
• a signal elimination section that extracts said first modulated signal by eliminating said second modulated signal replica signal from said received multiplex signal at predetermined timing;
• and
• a demodulation section that demodulates extracted said first modulated signal;
• wherein said despreading and demodulation section and/or said signal elimination section performs despreading and demodulation processing and/or signal elimination processing based on received said multiplex frame information and/or spreading code information.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which an OFDM modulated signal resulting from execution of OFDM modulation processing on an information signal and an OFDM-spreading modulated signal resulting from execution of OFDM-spreading modulation processing on an information signal are multiplexed in a same frequency band;
• a first demodulation section that demodulates an OFDM-spreading modulated signal within said multiplex signal;
• a regeneration section that forms a replica signal of an OFDM-spreading modulated signal by regenerating an OFDM-spreading modulated signal from a demodulated signal;
• a signal elimination section that extracts said OFDM modulated signal by eliminating said OFDM-spreading modulated signal replica signal from said received multiplex signal;
• and
• a second demodulation section that demodulates extracted said OFDM modulated signal.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which an OFDM modulated signal resulting from execution of OFDM modulation processing on an information signal and an OFDM-spreading modulated signal resulting from execution of OFDM-spreading modulation processing on an information signal are multiplexed in a same frequency band, and information of a spreading code used when performing OFDM-spreading modulation processing;
• a first demodulation section that demodulates an OFDM-spreading modulated signal within said multiplex signal based on said spreading code information;
• a regeneration section that forms a replica signal of an OFDM-spreading modulated signal by regenerating an OFDM-spreading modulated signal from a demodulated signal;
• a signal elimination section that extracts said OFDM modulated signal by eliminating said OFDM-spreading modulated signal replica signal from a received multiplex signal;
• and
• a second demodulation section that demodulates extracted said OFDM modulated signal.

A transmitting apparatus comprising:

• a first spreading section that obtains a first spread signal by spreading an information signal using a first spreading code that has a first spreading ratio;
• a second spreading section that obtains a second spread signal by spreading an information signal using a second spreading code that has a second spreading ratio different from said first spreading ratio;
• a multiplexing section that obtains a multiplex signal by multiplexing said first spread signal and said second spread signal in a same frequency band;
• and
• a transmission section that transmits said multiplex signal.

A transmitting apparatus comprising:

• a first OFDM-spreading modulation section that obtains a first OFDM-spreading modulated signal by performing spreading processing using a first spreading code that has a first spreading ratio and orthogonal frequency division multiplexing processing on an information signal;
• a second OFDM-spreading modulation section that obtains a second OFDM-spreading modulated signal by performing spreading processing using a second spreading code that has a second spreading ratio different from said first spreading ratio and orthogonal frequency division multiplexing processing on an information signal;
• a multiplexing section that obtains a multiplex signal by multiplexing said first OFDM-spreading modulated signal and said second OFDM-spreading modulated signal in a same frequency band;
• and
• a transmission section that transmits said multiplex signal.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which first and second spread spectrum signals formed using spreading codes with different spreading ratios on an information signal are multiplexed in a same frequency band;
• a first demodulation section that separates and demodulates said first spread spectrum signal from a received multiplex signal using a spreading code corresponding to said first spread spectrum signal;
• a regeneration section that forms a replica signal of a first spread spectrum signal by regenerating a first spread spectrum signal from a demodulated signal;
• a signal elimination section that extracts said second spread spectrum signal by eliminating said first spread spectrum signal replica signal from a received multiplex signal;
• and
• a second demodulation section that demodulates extracted said second spread spectrum signal.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which first and second OFDM-spreading modulated signals formed using spreading codes with different spreading ratios on an information signal and executing orthogonal frequency division multiplexing on signals after spreading are multiplexed in a same frequency band;
• a first demodulation section that separates and demodulates said first OFDM-spreading modulated signal from a received multiplex signal using a spreading code corresponding to said first OFDM-spreading modulated signal;
• a regeneration section that forms a replica signal of a first OFDM-spreading modulated signal by regenerating a first OFDM-spreading modulated signal from a demodulated signal;
• a signal elimination section that extracts said second OFDM-spreading modulated signal by eliminating said first OFDM-spreading modulated signal replica signal from a received multiplex signal;
• and
• a second demodulation section that demodulates extracted said second OFDM-spreading modulated signal.

A transmitting apparatus comprising:

• a first modulation section that obtains a spread signal by modulating an information signal using a spread spectrum system;
• a second modulation section that obtains a non-spread signal by modulating an information signal not using a spread spectrum system;
• a modulation selection section that, based on a propagation path environment of a transmission target station, selects said first modulation section and has spreading processing performed on an information signal directed to that transmission target station when said propagation path environment is poor, and selects said second modulation section and does not have spreading processing performed on an information signal directed to that transmission target station when said propagation environment is good;
• a multiplexing section that multiplexes a plurality of modulated signals that have undergone modulation processing by means of a selected modulation system in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal.

A transmitting apparatus comprising:

• an OFDM modulation section that executes orthogonal frequency division multiplexing processing on an information signal and obtains an OFDM modulated signal;
• an OFDM-spreading modulation section that executes spreading processing and orthogonal frequency division multiplexing processing on an information signal and obtains an OFDM-spreading modulated signal;
• a modulation selection section that, based on a propagation path environment of a transmission target station, selects said OFDM-spreading modulation section and has spreading processing and orthogonal frequency division multiplexing processing executed on an information signal directed to that transmission target station when said propagation path environment is poor, and selects said OFDM modulation section and has orthogonal frequency division multiplexing executed on an information signal directed to that transmission target station when said propagation environment is good;
• a multiplexing section that multiplexes a plurality of modulated signals that have undergone modulation processing by means of said selected modulation system in a same frequency band and obtains a multiplex signal;
• and
• a transmission section that transmits said multiplex signal.

A transmitting apparatus comprising:

• a first modulation section that obtains a spread signal by modulating an information signal using a spread spectrum system;
• and
• a second modulation section that obtains a non-spread signal by modulating an information signal not using a spread spectrum system;
• wherein by executing processing by said first and second modulation sections on a same information signal, a spread signal and non-spread signal are obtained for said same information signal, and that spread signal and non-spread signal are transmitted multiplexed in a same frequency band.

A transmitting apparatus comprising:

• an OFDM modulation section that obtains an OFDM modulated signal by executing orthogonal frequency division multiplexing processing on an information signal;
• and
• an OFDM-spreading modulation section that obtains an OFDM-spreading modulated signal by executing spreading processing and orthogonal frequency division multiplexing processing on an information signal;
• wherein by executing processing by said OFDM modulation section and OFDM-spreading modulation section on a same information signal, an OFDM modulated signal and OFDM-spreading modulated signal are obtained for said same information signal, and that OFDM modulated signal and OFDM-spreading modulated signal are transmitted multiplexed in a same frequency band.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which a spread signal and non-spread signal for a same information signal are multiplexed in a same frequency band;
• a despreading and demodulation section that demodulates a spread signal in a multiplex signal by despreading a received multiplex signal;
• a regeneration section that regenerates a spread signal from a demodulated signal and forms a replica signal of said spread signal;
• a signal elimination section that extracts said non-spread signal by eliminating said replica signal from said received multiplex signal;
• a demodulation section that demodulates extracted said non-spread signal;
• a radio wave propagation environment estimation section that estimates a radio wave propagation environment between said receiving apparatus and a transmitting station;
• and
• a selection section that selects either a demodulated spread signal or a demodulated non-spread signal based on an estimated radio wave propagation environment.

A receiving apparatus comprising:

• a reception section that receives a multiplex signal in which an OFDM modulated signal and an OFDM-spreading modulated signal for a same information signal are multiplexed in a same frequency band;
• a first demodulation section that demodulates an OFDM-spreading modulated signal in a received multiplex signal;
• a regeneration section that regenerates an OFDM-spreading modulated signal from a demodulated OFDM-spreading modulated signal and forms a replica signal of said OFDM-spreading modulated signal;
• a signal elimination section that extracts said OFDM modulated signal by eliminating said replica signal from said received multiplex signal;
• a second demodulation section that demodulates extracted said OFDM modulated signal;
• a radio wave propagation environment estimation section that estimates a radio wave propagation environment between said receiving apparatus and a transmitting station;
• and
• a selection section that selects either a demodulated OFDM modulated signal or a demodulated OFDM-spreading modulated signal based on an estimated radio wave propagation environment.