Receiver device, communication system and receiving method

1. A receiver device that receives a signal supplied to one or a plurality of ports as one or a plurality of received signals, comprising:

one or a plurality of processors that comprises a timing detector that performs timing detection by detecting a signal position of a received signal allocated beforehand from among said one or plurality of received signals in order to form a signal waveform of said received signals allocated beforehand, a frequency offset compensating unit that compensates a frequency offset of the received signal that is timing-detected by said timing detector, a serial-to-parallel converter that subjects the received signal compensated by said frequency offset compensating unit to a serial-to-parallel conversion, a Fourier transform unit that performs a Fourier transform of the received signal subjected to the serial-to-parallel conversion by said serial-to-parallel converter, an equalizer that equalizes the received signal subjected to the Fourier transform by said Fourier transform unit to each frequency component, an inverse Fourier transform unit that subjects the received signal equalized by said equalizer to an inverse Fourier transform, and a parallel-to-serial converter that subjects the received signal subjected to the inverse Fourier transform by said inverse Fourier transform unit to a parallel-to-serial conversion;

a signal synthesizer that synthesizes the signal waveform formed by said one or plurality of said processors;

a demodulator that demodulates the signal waveform synthesized by said signal synthesizer;

a phase offset estimating unit arranged on a received signal conversion path that runs from said timing detector to said demodulator to estimate a phase offset of the received signal on the basis of a unique word of each signal block contained in said received signal; and

a phase offset compensating unit arranged on said received signal conversion path to compensate the phase offset of the received signal on said received signal conversion path on the basis of the phase offset estimated by said phase offset estimating unit.

2. The receiver device according to claim 1 , wherein:

said phase offset estimating unit is arranged downstream of said parallel-to-serial converter to estimate said phase offset of the received signal on the basis of the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter;

said phase offset compensating unit is arranged downstream of said phase offset estimating unit to compensate the phase of the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal whose phase is compensated by said phase offset compensating unit.

3. The receiver device according to claim 1 , wherein:

said phase offset estimating unit is arranged downstream of said parallel-to-serial converter to estimate said phase offset on the basis of the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter;

said phase offset compensating unit is arranged downstream of said frequency offset compensating unit to compensate the phase of the received signal compensated by said frequency offset compensating unit on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal whose phase is compensated by said phase offset compensating unit.

4. The receiver device according to claim 1 , wherein:

said phase offset estimating unit is arranged downstream of said signal synthesizer to estimate said phase offset of the received signal on the basis of the received signal synthesized by said signal synthesizer;

said phase offset compensating unit is arranged downstream of said phase offset estimating unit to compensate the phase of the received signal synthesized by said signal synthesizer on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter.

5. The receiver device according to claim 1 , wherein:

said phase offset estimating unit is arranged downstream of said signal synthesizer to estimate said phase offset of the received signal on the basis of the received signal synthesized by said signal synthesizer;

said phase offset compensating unit is arranged downstream of said frequency offset estimating unit to compensate the phase of the received signal compensated by said frequency offset compensating unit on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter.

6. The receiver device according to claim 1 , wherein:

each signal block of said received signal contains a preamble signal and a plurality of said unique words; and

said frequency offset compensating unit comprises

a first frequency offset estimating unit that uses the preamble signal contained in the received signal timing-detected by said timing detector to calculate a first frequency offset estimated value,

a first frequency offset compensating unit that uses the first frequency offset estimated value calculated by said first frequency offset estimating unit to compensate the frequency offset of the received signal timing-detected by said timing detector,

a second frequency offset estimating unit that uses the plurality of the unique words contained in the received signal whose frequency offset is compensated by said first frequency offset compensating unit to calculate a second frequency offset estimated value, and

a second frequency offset compensating unit that uses the second frequency offset estimated value calculated by said second frequency offset estimating unit to compensate the frequency offset of the received signal whose frequency offset is compensated by said first frequency offset compensating unit.

7. The receiver device according to claim 1 , further comprising a signal distributor that distributes said one or plurality of received signals, the received signals allocated beforehand from among the received signals distributed by said signal distributor being supplied to said one or plurality of processors.

8. The receiver device according to claim 1 , wherein said phase offset estimating unit estimates said phase offset θ(q) of said received signal according to the following general equation:

θ

⁡

(

q

)

=

arg

⁢

{

∑

m

=

1

M

⁢

y

⁡

(

m

,

q

)

⁢

x

⁡

(

m

)

*

}

where y(m,q) is the received signal in the q-th signal block, x(m) is a unique word sequence, parameter m is an identification variable for sequentially identifying each unique word block of M blocks, * denotes a complex conjugate, and arg is a function for determining an angle.

9. A communication system comprising:

a transmitter device that transmits a signal in which a unique word is added to each signal block thereof; and

a receiver device that receives a signal supplied to one or a plurality of ports as one or a plurality of received signals;

the receiver device comprising:

one or a plurality of processors that comprises a timing detector that performs timing detection by detecting a signal position of a received signal allocated beforehand from among said one or plurality of received signals in order to form a signal waveform of said received signals allocated beforehand, a frequency offset compensating unit that compensates a frequency offset of the received signal that is timing-detected by said timing detector, a serial-to-parallel converter that subjects the received signal compensated by said frequency offset compensating unit to a serial-to-parallel conversion, a Fourier transform unit that performs a Fourier transform of the received signal subjected to the serial-to-parallel conversion by said serial-to-parallel converter, an equalizer that equalizes the received signal subjected to the Fourier transform by said Fourier transform unit to each frequency component, an inverse Fourier transform unit that subjects the received signal equalized by said equalizer to an inverse Fourier transform, and a parallel-to-serial converter that subjects the received signal subjected to the inverse Fourier transform by said inverse Fourier transform unit to a parallel-to-serial conversion;

a signal synthesizer that synthesizes the signal waveform formed by said one or plurality of said processors;

a demodulator that demodulates the signal waveform synthesized by said signal synthesizer;

a phase offset estimating unit arranged on a received signal conversion path that runs from said timing detector to said demodulator to estimate a phase offset of the received signal on the basis of a unique word of each signal block contained in said received signal; and

a phase offset compensating unit arranged on said received signal conversion path to compensate the phase offset of the received signal on said received signal conversion path on the basis of the phase offset estimated by said phase offset estimating unit.

10. The communication system according to claim 9 , wherein:

said phase offset estimating unit is arranged downstream of said parallel-to-serial converter to estimate said phase offset of the received signal on the basis of the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter;

said phase offset compensating unit is arranged downstream of said phase offset estimating unit to compensate the phase of the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal whose phase is compensated by said phase offset compensating unit.

11. The communication system according to claim 9 , wherein:

said phase offset estimating unit is arranged downstream of said parallel-to-serial converter to estimate said phase offset of the received signal on the basis of the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter;

said phase offset compensating unit is arranged downstream of said frequency offset compensating unit to compensate the phase of the received signal compensated by said frequency offset compensating unit on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal whose phase is compensated by said phase offset compensating unit.

12. The communication system according to claim 9 , wherein:

said phase offset estimating unit is arranged downstream of said signal synthesizer to estimate said phase offset of the received signal on the basis of the received signal synthesized by said signal synthesizer;

said phase offset compensating unit is arranged downstream of said phase offset estimating unit to compensate the phase of the received signal synthesized by said signal synthesizer on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter.

13. The communication system according to claim 9 , wherein:

said phase offset estimating unit is arranged downstream of said signal synthesizer to estimates said phase offset of the received signal on the basis of the received signal synthesized by said signal synthesizer;

said phase offset compensating unit is arranged downstream of said frequency offset estimating unit to compensate the phase of the received signal compensated by said frequency offset compensating unit on the basis of the phase offset of each signal block estimated by said phase offset estimating unit; and

said signal synthesizer synthesizes the received signal subjected to the parallel-to-serial conversion by said parallel-to-serial converter.

14. The communication system according to claim 9 , wherein:

each signal block of said received signal contains a preamble signal and a plurality of said unique words; and

said frequency offset compensating unit comprises

a first frequency offset estimating unit that uses the preamble signal contained in the received signal timing-detected by said timing detector to calculate a first frequency offset estimated value,

a first frequency offset compensating unit that uses the first frequency offset estimated value calculated by said first frequency offset estimating unit to compensate the frequency offset of the received signal timing-detected by said timing detector,

a second frequency offset estimating unit that uses the plurality of the unique words contained in the received signal whose frequency offset is compensated by said first frequency offset compensating unit to calculate a second frequency offset estimated value, and

a second frequency offset compensating unit that uses the second frequency offset estimated value calculated by said second frequency offset estimating unit to compensate the frequency offset of the received signal whose frequency offset is compensated by said first frequency offset compensating unit.

15. The communication system according to claim 9 , further comprising a signal distributor that distributes said one or plurality of received signals, the received signals allocated beforehand from among the received signals distributed by said signal distributor being supplied to said one or plurality of processors.

16. The communication system according to claim 9 , wherein said phase offset estimating unit estimates said phase offset θ(q) of said received signal according to the following general equation:

θ

⁡

(

q

)

=

arg

⁢

{

∑

m

=

1

M

⁢

y

⁡

(

m

,

q

)

⁢

x

⁡

(

m

)

*

}

where y(m,q) is the received signal in the q-th signal block, x(m) is a unique word sequence, parameter m is an identification variable for sequentially identifying each unique word block of M blocks, * denotes a complex conjugate, and arg is a function for determining an angle.

17. A receiving method used in a receiver device that receives a signal supplied to one or a plurality of ports as one or a plurality of received signals, the method comprising:

a processing step comprising a timing-detection step of performing timing detection with respect to said one or plurality of received signals by detecting a signal position of a received signal allocated beforehand from among said one or plurality of received signals, a frequency offset compensation step of compensating a frequency offset of the received signal that is timing-detected in said timing detection step, a serial-to-parallel conversion step of subjecting the received signal compensated in said frequency offset compensation step to a serial-to-parallel conversion, a Fourier transform step of performing a Fourier transform of the received signal subjected to the serial-to-parallel conversion in said serial-to-parallel conversion step, an equalization step of equalizing the received signal subjected to the Fourier transform in said Fourier transform step to each frequency component, an inverse Fourier transform step of subjecting the received signal equalized in said equalization step to an inverse Fourier transform, and a parallel-to-serial conversion step of subjecting the received signal subjected to an inverse Fourier transform in said inverse Fourier transform step to a parallel-to-serial conversion;

a signal synthesis step of synthesizing the signal waveform formed in said processing step;

a demodulation step of demodulating the signal waveform synthesized in said signal synthesis step;

a phase offset estimation step of estimating a phase offset of the received signal that runs from said timing-detection step to said demodulation step on the basis of a unique word of each signal block contained in said received signal; and

a phase offset compensation step of compensating the phase offset of the received signal on the basis of the phase offset estimated in said phase offset estimation step.

18. The receiving method according to claim 17 , wherein:

said phase offset estimation step is performed subsequent to said parallel-to-serial conversion step to estimate said phase offset on the basis of the received signal subjected to the parallel-to-serial conversion in said parallel-to-serial conversion step;

said phase offset compensation step is performed subsequent to said phase offset estimation step to compensate the phase of the received signal subjected to the parallel-to-serial conversion in said parallel-to-serial conversion step on the basis of the phase offset of each signal block estimated by said phase offset estimation step; and

said signal synthesis step synthesizes the received signal whose phase is compensated in said phase offset compensation step.

19. The receiving method according to claim 17 , wherein:

said phase offset estimation step is performed subsequent to said parallel-to-serial conversion step to estimate said phase offset on the basis of the received signal subjected to the parallel-to-serial conversion in said parallel-to-serial conversion step;

said phase offset compensation step is performed subsequent to said frequency offset compensation step to compensate the phase of the received signal compensated in said frequency offset compensation step on the basis of the phase offset of each signal block estimated by said phase offset estimation step; and

said signal synthesis step synthesizes the received signal whose phase is compensated in said phase offset compensation steps.

20. The receiving method according to claim 17 , wherein:

said phase offset estimation step is performed subsequent to said signal synthesis step to estimate said phase offset on the basis of the received signal synthesized in said signal synthesis step;

said phase offset compensation step is performed subsequent to said phase offset estimation step to compensate the phase of the received signal synthesized in said signal synthesis step on the basis of the phase offset of each signal block estimated in said phase offset estimation step; and

said signal synthesis step synthesizes the received signal subjected to the parallel-to-serial conversion in said parallel-to-serial conversion step.

21. The receiving method according to claim 17 , wherein:

said phase offset estimation step is performed subsequent to said signal synthesis step to estimate said phase offset on the basis of the received signal synthesized in said signal synthesis step;

said phase offset compensation step is performed subsequent to said frequency offset estimation step to compensate the phase of the received signal compensated in said frequency offset compensation step on the basis of the phase offset of each signal block estimated in said phase offset estimation step; and

said signal synthesis step synthesizes the received signal subjected to the parallel-to-serial conversion in said parallel-to-serial conversion step.

22. The receiving method according to claim 17 , wherein:

each signal block of said received signal contains a preamble signal and a plurality of said unique words; and

said frequency offset compensation step comprises

a first frequency offset estimation step of using the preamble signal contained in the received signal timing-detected in said timing-detection step to calculate a first frequency offset estimated value,

a first frequency offset compensation step of using the first frequency offset estimated value calculated in said first frequency offset estimation step to compensate the frequency offset of the received signal timing-detected in said timing-detection step,

a second frequency offset estimation step of using the plurality of the unique words contained in the received signal whose frequency offset is compensated in said first frequency offset compensation step to calculate a second frequency offset estimated value, and

a second frequency offset compensation step of using the second frequency offset estimated value calculated in said second frequency offset estimation step to compensate the frequency offset of the received signal whose frequency offset is compensated in said first frequency offset compensation step.

23. The receiving method according to claim 17 , further comprising:

a signal distribution step of distributing said one or plurality of received signals; and

a supply step of supplying the received signal allocated beforehand from among the received signals distributed in said signal distribution step, to said processing step.

24. The receiving method according to claim 17 , wherein said phase offset estimation step estimates said phase offset θ(q) of said received signal according to the following general equation:

θ

⁡

(

q

)

=

arg

⁢

{

∑

m

=

1

M

⁢

y

⁡

(

m

,

q

)

⁢

x

⁡

(

m

)

*

}

where y(m,q) is the received signal in the q-th signal block, x(m) is a unique word sequence, parameter m is an identification variable for sequentially identifying each unique word block of M blocks, * denotes a complex conjugate, and arg is a function for determining an angle.