Transmission method, transmission device, reception method, and reception device
Provided is a transmission method that improves data reception quality in radio transmission using a single-carrier scheme and/or a multi-carrier scheme. The transmission method includes: generating a plurality of first modulated signals and a plurality of second modulated signals from transmission data, the plurality of first modulated signals being signals generated using a 16QAM modulation scheme, and the plurality of second modulated signals being signals generated using uniform constellation 64QAM modulation; generating, from the plurality of first modulated signals and the plurality of second modulated signals, a plurality of first signal-processed signals and a plurality of second signal-processed signals which satisfy a predetermined equation; and changing the predetermined equation when a 64QAM modulation used to generate the plurality of second modulated signals is switched from the uniform constellation 64QAM modulation to a non-uniform constellation 64QAM modulation.
1. A transmission method, comprising:
generating modulated 16-quadrature amplitude modulation (QAM) points s1(i) by using bits of a first stream and generating modulated quadrature phase shift keying (QPSK) points s2(i) by using bits of a second stream, where i is an integer greater than or equal to 0;
converting the modulated 16-QAM points s1(i) to first converted points z1(i) and converting the modulated QPSK points s2(i) to second converted points z2(i), wherein converting the modulated 16-QAM points s1(i) to the first converted points z1(i) and converting the modulated QPSK points s2(i) to the second converted points z2(i) includes multiplying
(
s
1
(
i
)
s
2
(
i
)
)
by
(
4
/
3
0
0
2
/
3
)
;
(
i
)
generating one or more signals that include the first converted points z1(i) and the second converted points z2(i); and
transmitting the one or more signals.
2. The transmission method of claim 1 , wherein the first converted points z1(i) and the second converted points z2(i) are defined as:
(
z
1
(
i
)
z
2
(
i
)
)
=
(
1
0
0
y
(
i
)
)
1
2
(
1
1
1
-
1
)
(
4
/
3
0
0
2
/
3
)
(
s
1
(
i
)
s
2
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i
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)
,
where y(i) is a function represented by e jδ(i) where δ(i) is a real value incremented by a constant value for every i.
3. The transmission method of claim 2 , wherein the constant value is 2π/N.
4. The transmission method of claim 2 , wherein the one or more signals comprise one or more orthogonal frequency division multiplexing (OFDM) symbols.
5. The transmission method of claim 2 , wherein the transmission method is to be performed by a base station.
6. The transmission method of claim 2 , further comprising:
receiving a control signal;
selecting a precoding matrix from a plurality of precoding matrixes based on the control signal; and
performing a precoding based on the precoding matrix.
7. The transmission method of claim 2 , further comprising:
generating the first converted points z1(i) or the second converted points z2(i) based on one or more phase change values.
8. The transmission method of claim 2 , wherein a value of y(i) periodically varies with a period of N, where N is 8.
9. A device comprising:
a mapper to generate modulated 16-quadrature amplitude modulation (QAM) points s1(i) by using bits of a first stream, and to generate modulated quadrature phase shift keying (QPSK) points s2(i) by using bits of a second stream, where i is an integer greater than or equal to 0;
a signal processor to convert the modulated 16-QAM points s1(i) to first converted points z1(i) and to convert the modulated QPSK points s2(i) to second converted points z2(i), wherein to convert the modulated 16-QAM points s1(i) to the first converted points z1(i) and to convert the modulated QPSK points s2(i) to the second converted points z2(i), the signal processor is to multiply
(
s
1
(
i
)
s
2
(
i
)
)
by
(
4
/
3
0
0
2
/
3
)
;
(
i
)
and
a generator to generate one or more signals that include the first converted points z1(i) and the second converted points z2(i).
10. The device of claim 9 , wherein the first converted points z1(i) and the second converted points z2(i) are defined as:
(
z
1
(
i
)
z
2
(
i
)
)
=
(
1
0
0
y
(
i
)
)
1
2
(
1
1
1
-
1
)
(
4
/
3
0
0
2
/
3
)
(
s
1
(
i
)
s
2
(
i
)
)
,
where y(i) is a function represented by e jδ(i) and δ(i) is a real value incremented by a constant value for every i.
11. The device of claim 10 , wherein the constant value is 27π/ N.
12. The device of claim 10 , further comprising:
a transmitter to transmit the one or more signals.
13. The device of claim 12 , wherein the transmitter is to transmit the one or more signals via a plurality of antennas.
14. The device of claim 10 , wherein the device comprises a base station.
15. The device of claim 10 , wherein the signal processor is further configured to:
receive a control signal;
select a precoding matrix from a plurality of precoding matrixes based on the control signal; and
perform a precoding based on the precoding matrix.
16. The device of claim 10 , wherein the signal processor is further configured to:
generate the first converted points z1(i) or the second converted points z2(i) based on one or more phase change values.
17. The device of claim 10 , wherein a value of y(i) periodically varies with a period of N, where N is 8.
18. A reception method, comprising:
obtaining one or more reception signals that include a first converted signal z1(i) and a second converted signal z2(i), where i is an integer greater than or equal to 0,
wherein the first converted signal z1(i) and the second converted signal z2(i) are generated by multiplying
(
s
1
(
i
)
s
2
(
i
)
)
by
(
4
/
3
0
0
2
/
3
)
,
(
i
)
where s1(i) is modulated 16-quadrature amplitude modulation (QAM) points and s2(i) is modulated quadrature phase shift keying (QPSK) points; and
demodulating the first converted signal z1(i) according to a conversion applied to the modulated 16-QAM points s1(i) and demodulating the second converted signal z2(i) according to a conversion applied to the modulated QPSK points s2(i).
19. The reception method of claim 18 , wherein the first converted signal z1(i) and the second converted signal z2(i) are defined as:
(
z
1
(
i
)
z
2
(
i
)
)
=
(
1
0
0
y
(
i
)
)
1
2
(
1
1
1
-
1
)
(
4
/
3
0
0
2
/
3
)
(
s
1
(
i
)
s
2
(
i
)
)
,
where y(i) is a function represented by e jδ(i) and δ(i) is a real value incremented by a constant value for every i.
20. The reception method of claim 19 , wherein the constant value is 2π/N.
21. The reception method of claim 19 , wherein the one more reception signals comprise orthogonal frequency division multiplexing (OFDM) symbols.
22. The reception method of claim 19 , wherein a value of y(i) periodically varies with a period of N, where N is 8.
23. A reception device, comprising:
a receiver to receive one or more reception signals that include a first converted signal z1(i) and a second converted signal z2(i), where i is an integer greater than or equal to 0,
wherein the first converted signal z1(i) and the second converted signal z2(i) are generated by multiplying
(
s
1
(
i
)
s
2
(
i
)
)
by
(
4
/
3
0
0
2
/
3
)
,
(
i
)
where s1(i) are modulated 16-quadrature amplitude modulation (QAM) points and s2(i) are modulated quadrature phase shift keying (QPSK) points; and
a demodulator to demodulate the first converted signal z1(i) according to a conversion applied to the modulated 16-QAM points s1(i) and demodulate the second converted signal z2(i) according to a conversion applied to the modulated QPSK points s2(i).
24. The reception device of claim 23 , wherein the first converted signal z1(i) and the second converted signal z2(i) are defined as:
(
z
1
(
i
)
z
2
(
i
)
)
=
(
1
0
0
y
(
i
)
)
1
2
(
1
1
1
-
1
)
(
4
/
3
0
0
2
/
3
)
(
s
1
(
i
)
s
2
(
i
)
)
,
where y(i) is a function represented by e jδ(i) where δ(i) is a real value incremented by a constant value for every i.
25. The reception device of claim 24 , wherein the constant value is 2π/N.
26. The reception device of claim 24 , wherein the one or more reception signals comprise orthogonal frequency divisional multiplexing (OFDM) symbols.
27. The reception device of claim 24 , wherein a value of y(i) periodically varies with a period of N, where N is 8.