MULTICARRIER MODULATION SCHEME AS WELL AS TRANSMISSION APPARATUS AND RECEPTION APPARATUS USING THE SCHEME

• US 20090268837A1
• Filed: 12/18/2006
• Published: 10/29/2009
• Est. Priority Date: 01/10/2006
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Mori, Kenichi, Kimura, Tomohiro, Omoto, Yukihiro
• Granted Patent: US 8,179,986 B2
• Time in Patent Office: Days
• US Class Current: 375/267
• CPC Class Codes: H04L 2025/03414 Multicarrier
• CPC Class Codes: H04L 25/022 of frequency response
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 25/0228 with direct estimation from sounding signals
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/2698 double density OFDM/OQAM system, e.g. OFDM/OQAM-IOTA system
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver

Abstract

An object is to generate a pilot signal for estimating transmission characteristic of a transmission channel which is suitable for the OFDM/OQAM multicarrier modulation. A phase reference pilot symbol of which a modulation amplitude is suppressed to zero, and an amplitude reference pilot signal obtained through modulation performed by using an amplitude known to a reception end are transmitted from a transmission end, and the transmission characteristic of the transmission channel is estimated and compensated by using the phase reference pilot signal and the amplitude reference pilot signal at the reception end. Thus, it is possible to simplify frame generation process performed at the transmission end, and reduce transmission power for the phase reference pilot signal.

Claims

1. A multicarrier modulation scheme in which ν

τ

=½

is satisfied when τ

represents a symbol transmission interval, and ν

represents frequency intervals of a plurality of carriers,

wherein a multicarrier modulated signal generated by performing a modulation in the multicarrier modulation scheme includes a phase reference pilot signal, and

wherein the phase reference pilot signal is a null signal (a signal obtained through a modulation performed by using an amplitude value which is zero).

2. The multicarrier modulation scheme according to claim 1, wherein a plurality of the phase reference pilot signals are located in a plurality of symbols, respectively, which are continuous in a time direction on a predetermined carrier.

7. A transmission apparatus for performing the modulation in the multicarrier modulation scheme according to claim 1 so as to generate the multicarrier modulated signal, and transmitting the multicarrier modulated signal.

10. A reception apparatus

wherein the multicarrier modulated signal generated in the multicarrier modulation scheme according to claim 1 is received, and

wherein a shift of a phase of the multicarrier modulated signal is estimated by using the phase reference pilot signal included in the multicarrier modulated signal, so as to compensate the phase.

3. A multicarrier modulation scheme in which ν

τ

=½

is satisfied when τ

represents a symbol transmission interval, and ν

represents frequency intervals of a plurality of carriers,

wherein a multicarrier modulated signal generated by performing a modulation in the multicarrier modulation scheme includes a phase reference pilot signal and an amplitude reference pilot signal, and

wherein the phase reference pilot signal is a null signal (a signal obtained through a modulation performed by using an amplitude value which is zero), and the amplitude reference pilot signal is a signal obtained through a modulation performed by using an amplitude value known to a reception end.

4. The multicarrier modulation scheme according to claim 3, wherein the phase reference pilot signal and the amplitude reference pilot signal are located alternately every other symbol over a plurality of symbols which are continuous in a time direction on a predetermined carrier.

5. The multicarrier modulation scheme according to claim 3, wherein the phase reference pilot signal and the amplitude reference pilot signal are located alternately every other carrier over a plurality of carriers which are continuous in a frequency direction in a predetermined symbol.

6. The multicarrier modulation scheme according to claim 3, wherein the phase reference pilot signal and the amplitude reference pilot signal are located alternately every other carrier in a frequency direction, and are located alternately every other symbol in a time direction.

11. A reception apparatus,

wherein the multicarrier modulated signal generated in the multicarrier modulation scheme according to claim 3 is received,

wherein a shift of a phase of the multicarrier modulated signal is estimated by using the phase reference pilot signal included in the multicarrier modulated signal, so as to compensate the phase, and

wherein a difference of an amplitude of the multicarrier modulated signal is estimated by using the amplitude reference pilot signal included in the multicarrier modulated signal, so as to compensate the amplitude.

8. A transmission apparatus for generating a multicarrier modulated signal in a multicarrier modulation scheme in which ν

τ

=½

is satisfied when τ

represents a symbol transmission interval, and ν

represents frequency intervals of a plurality of carriers, and transmitting the multicarrier modulated signal, the transmission apparatus comprising;

frame generation means for receiving transmission data, and generating a frame signal including an amplitude value for generating a data transmission signal based on the transmission data, and an amplitude value of zero for generating a phase reference pilot signal; and

multicarrier modulation means for generating the multicarrier modulated signal, using amplitude value information included in the frame signal, in the multicarrier modulation scheme.

9. A transmission apparatus for generating a multicarrier modulated signal in a multicarrier modulation scheme in which ν

τ

=½

is satisfied when τ

represents a symbol transmission interval, and ν

represents frequency intervals of a plurality of carriers, and transmitting the multicarrier modulated signal, the transmission apparatus comprising;

frame generation means for receiving transmission data, and generating a frame signal including an amplitude value for generating a data transmission signal based on the transmission data, an amplitude value of zero for generating a phase reference pilot signal, and an amplitude value, known to a reception end, for generating an amplitude reference pilot signal; and

multicarrier modulation means for generating the multicarrier modulated signal, using amplitude value information included in the frame signal, in the multicarrier modulation scheme.

12. A reception apparatus for receiving and demodulating a multicarrier modulated signal generated in a multicarrier modulation scheme in which ν

τ

=½

is satisfied when τ

represents a symbol transmission interval, and ν

represents frequency intervals of a plurality of carriers,

wherein the multicarrier modulated signal includes a phase reference pilot signal which is a null signal (a signal obtained through a modulation performed by using an amplitude value which is zero), the reception apparatus comprising

multicarrier demodulation means for demodulating the received multicarrier modulated signal so as to generate a demodulation vector, and outputting the demodulation vector, and

equalization means for receiving the demodulation vector, and estimating a shift of a phase of the demodulation vector in accordance with the phase reference pilot signal, so as to compensate the phase.

13. The reception apparatus according to claim 12, wherein

the equalization means includes

phase estimation means for extracting the phase reference pilot signal included in the demodulation vector, and estimating the shift of the phase of the demodulation vector, and

phase compensation means for compensating the phase of the demodulation vector in accordance with the shift of the phase estimated by the phase estimation means.

14. A reception apparatus for receiving and demodulating a multicarrier modulated signal obtained through a modulation performed in a multicarrier modulation scheme in which ν

τ

=½

is satisfied when τ

represents a symbol transmission interval, and ν

represents frequency intervals of a plurality of carriers,

wherein the multicarrier modulated signal includes a phase reference pilot signal which is a null signal (a signal obtained through a modulation performed by using an amplitude value which is zero), and an amplitude reference pilot signal obtained through a modulation performed by using an amplitude known to a reception end, the reception apparatus comprising

multicarrier demodulation means for demodulating the received multicarrier modulated signal so as to generate a demodulation vector, and outputting the demodulation vector, and

equalization means for receiving the demodulation vector, and estimating a shift of a phase of the demodulation vector by using the phase reference pilot signal so as to compensate the phase, and estimating a difference of an amplitude of the demodulation vector by using the amplitude reference pilot signal so as to compensate the amplitude.

15. The reception apparatus according to claim 14, wherein

the equalization means includes:

phase estimation means for extracting the phase reference pilot signal included in the demodulation vector, and estimating the shift of the phase of the demodulation vector;

phase compensation means for compensating the phase of the demodulation vector in accordance with the shift of the phase estimated by the phase estimation means;

amplitude estimation means for extracting the amplitude reference pilot signal included in the demodulation vector which is phase-compensated and is outputted by the phase compensation means, and estimating a difference of an amplitude of the phase-compensated demodulation vector; and

amplitude compensation means for compensating, in accordance with the difference of the amplitude estimated by the amplitude estimation means, the amplitude of the demodulation vector which is phase-compensated and is outputted by the phase compensation means.

16. The reception apparatus according to claim 14, wherein

the equalization means includes:

phase estimation means for extracting the phase reference pilot signal included in the demodulation vector, and estimating the shift of the phase of the demodulation vector;

phase compensation means for compensating the phase of the demodulation vector in accordance with the shift of the phase estimated by the phase estimation means;

amplitude estimation means for extracting the amplitude reference pilot signal included in the demodulation vector which is phase-compensated and is outputted by the phase compensation means, and estimating a difference of an amplitude of the phase-compensated demodulation vector; and

compensation means for compensating, in accordance with the shift of the phase estimated by the phase estimation means and the difference of the amplitude estimated by the amplitude estimation means, the phase and an amplitude of the demodulation vector.