US 6,959,052 B2Granted

Receiving apparatus, receiving method, program and information recording medium

AssigneesNational Institute of Information and Communications Technology, Incorporated Administrative Agency, Denso Corporation

InventorsHiroshi Harada, Masayuki Fujise, Ryuuhei Funada, Manabu Sawada, Kunihiko Sasaki

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Abstract

A channel evaluator acquires a change predicted value from a known symbol, and a compensator compensates for a first symbol using the change predicted value. A demodulator restores a portion corresponding to this symbol with another subcarrier. A replica generator acquires a transmission replica of the restored symbol. The channel evaluator performs complex division on the replica with the symbol to acquire an amplitude phase ratio. A detector compares the amplitude phase ratio with an amplitude phase ratio acquired immediately previously. In case where an elimination condition is satisfied, the detector disregards the amplitude phase ratio acquired currently and uses an immediately previous value instead, an averaging unit averages amplitude phase ratios to acquire a next change predicted value, and the compensator compensates for a next symbol using the change predicted value. Hereinafter, the sequence of processes is repeated.

Claims26

Dependent claims

A receiving apparatus comprising:

a reception section that receives a result of transmitting a transmission signal obtained by modulating a known signal and a data signal and outputs said result as a reception signal;
a prediction section that predicts a transmission characteristic;
a compensation section that compensates that portion of said reception signal which corresponds to said data signal and which has not been compensated yet, using a predicted portion of said transmission characteristic, and outputs said compensated portion as a compensated data signal;
a demodulation section that demodulates said compensated data signal and outputs said demodulated signal as a demodulated data signal;
and
a modulation section that modulates said demodulated data signal and outputs said modulated signal as a modulated data signal,
whereby said prediction section
(a) compares that portion of said reception signal which corresponds to said known signal with a result of modulating said known signal and compares that portion of said reception signal which corresponds to said data signal with that portion of said modulated data signal which corresponds to said data signal to acquire a time series of comparison results,
(b) replaces a value in said time series of comparison results which satisfies a predetermined exclusion condition with an old value of said time series of comparison results,
(c) averages a time series of comparison results resulting from that replacement, and
(d) lets a result of that averaging be a predicted transmission characteristic.

8 more elements

A receiving apparatus comprising:

a reception section that receives a result of transmitting a transmission signal obtained by modulating a known signal and a data signal and outputs said result as a reception signal by a multi-carrier transmission system using carrier frequencies orthogonal to each other;
a separation section that separates said reception signal to reception signals for respective carrier frequencies by serial-parallel conversion and fast Fourier transform and outputs said separated reception signals as separated signals;
a prediction section that predicts a transmission characteristic for each of said carrier frequencies;
a compensation section that compensates that portion of each of said reception signals which corresponds to said data signal and which has not been compensated yet, using a predicted portion of said transmission characteristic, and outputs those compensated portions as compensated data signals;
a restoration section that performs serial-parallel conversion on said compensated data signals and outputs resultant signals as a restored data signal;
and
a modulation section that modulates said restored data signal and outputs said modulated signal as a modulated data signal,
whereby for that separated signal which is included in said separated signals and corresponds to each of said carrier frequencies, said prediction section
(a) compares that portion of said separated signal which corresponds to said known signal with a result of modulating said known signal and compares that portion of said separated signal which corresponds to said data signal with that portion of said modulated data signal which corresponds to said data signal to acquire a time series of comparison results,
(b) replaces a value in said time series of comparison results which satisfies a predetermined exclusion condition with an old value of said time series of comparison results,
(c) averages a time series of comparison results resulting from that replacement, and
(d) lets a result of that averaging be a predicted transmission characteristic.

9 more elements

A receiving method comprising:

a reception step that receives a result of transmitting a transmission signal obtained by modulating a known signal and a data signal and outputs said result as a reception signal;
a prediction step that predicts a transmission characteristic;
a compensation step that compensates that portion of said reception signal which corresponds to said data signal and which has not been compensated yet, using a predicted portion of said transmission characteristic, and outputs said compensated portion as a compensated data signal;
a demodulation step that demodulates said compensated data signal and outputs said demodulated signal as a demodulated data signal;
and
a modulation step that modulates said demodulated data signal and outputs said modulated signal as a modulated data signal,
whereby said prediction step
(a) compares that portion of said reception signal which corresponds to said known signal with a result of modulating said known signal and compares that portion of said reception signal which corresponds to said data signal with that portion of said modulated data signal which corresponds to said data signal to acquire a time series of comparison results,
(b) replaces a value in said time series of comparison results which satisfies a predetermined exclusion condition with an old value of said time series of comparison results,
(c) averages a time series of comparison results resulting from that replacement, and
(d) lets a result of that averaging be a predicted transmission characteristic.

8 more elements

A receiving method comprising:

a reception step that receives a result of transmitting a transmission signal obtained by modulating a known signal and a data signal and outputs said result as a reception signal by a multi-carrier transmission system using carrier frequencies orthogonal to each other;
a separation step that separates said reception signal to reception signals for respective carrier frequencies by serial-parallel conversion and fast Fourier transform and outputs said separated reception signals as separated signals;
a prediction step that predicts a transmission characteristic for each of said carrier frequencies;
a compensation step that compensates that portion of each of said reception signals which corresponds to said data signal and which has not been compensated yet, using a predicted portion of said transmission characteristic, and outputs those compensated portions as compensated data signals;
a restoration step that performs serial-parallel conversion on said compensated data signals and outputs resultant signals as a restored data signal;
and
a modulation step that modulates said restored data signal and outputs said modulated signal as a modulated data signal,
whereby for that separated signal which is included in said separated signals and corresponds to each of said carrier frequencies, said prediction step
(a) compares that portion of said separated signal which corresponds to said known signal with a result of modulating said known signal and compares that portion of said separated signal which corresponds to said data signal with that portion of said modulated data signal which corresponds to said data signal to acquire a time series of comparison results,
(b) replaces a value in said time series of comparison results which satisfies a predetermined exclusion condition with an old value of said time series of comparison results,
(c) averages a time series of comparison results resulting from that replacement, and
(d) lets a result of that averaging be a predicted transmission characteristic.

9 more elements

Dependencies are inferred from the claim text.