Precoding method, transmitting device, and receiving device
A transmission scheme for transmitting a first modulated signal and a second modulated signal in the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a precoding weight by a baseband signal after a first mapping and a baseband signal after a second mapping and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.
1. An integrated circuit comprising:
circuitry, which, in operation, controls generating a control signal indicating whether or not to perform a precoding process on a first signal s 1 ( t ) and a second signal s 2 ( t ); and
transmitting the control signal and a plurality of transmission signals generated from the first signal s 1 ( t ) and the second signal s 2 ( t ),
wherein
in case the precoding process is performed, a first transmission signal z 1 ( t ) and a second transmission signal z 2 ( t ) of the plurality of transmission signals are generated by precoding the first signal s 1 ( t ) and the second signal s 2 ( t ) in accordance with Equation 1,
(
z
1
(
t
)
z
2
(
t
)
)
=
1
2
(
e
j
0
e
j
0
e
j
θ
21
(
i
)
e
j
(
θ
21
(
i
)
+
π
)
)
(
s
1
(
t
)
s
2
(
t
)
)
θ
21
(
0
)
=
0
,
θ
21
(
1
)
=
π
2
(
Equation
1
)
where i varies according to t, and θ 21 (i) is a function with i that is a set of 0 and 1.
2. An integrated circuit comprising:
circuitry, which, in operation, controls
receiving a control signal and a plurality of transmission signals generated from a first signal s 1 ( t ) and a second signal s 2 ( t ), the control signal indicating whether or not a precoding process is applied on the first signal s 1 ( t ) and the second signal s 2 ( t ); and
decoding the plurality of transmission signals based on the control signal,
wherein
in case the precoding process is performed, a first transmission signal z 1 ( t ) and a second transmission signal z 2 ( t ) of the plurality of transmission signals are generated by precoding the first signal s 1 ( t ) and the second signal s 2 ( t ) in accordance with Equation 1,
(
z
1
(
t
)
z
2
(
t
)
)
=
1
2
(
e
j
0
e
j
0
e
j
θ
21
(
i
)
e
j
(
θ
21
(
i
)
+
π
)
)
(
s
1
(
t
)
s
2
(
t
)
)
θ
21
(
0
)
=
0
,
θ
21
(
1
)
=
π
2
(
Equation
1
)
where i varies according to t, and θ 21 (i) is a function with i that is a set of 0 and 1.