Receiving method and receiving apparatus
All data symbols used in data transmission of a modulated signal are precoded by switching between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol along the frequency axis and the time axis all differ. A modulated signal with such data symbols arranged therein is transmitted.
1 . An integrated circuit comprising:
generation circuitry, which in operation, controls a generation of first precoded symbols z 1 ( t ) and second precoded symbols z 2 ( t ), the first precoded symbols z 1 ( t ) and the second precoded symbols z 2 ( t ) being generated by performing a precoding process on the first modulated symbols s 1 ( t ) and the second modulated symbols s 2 ( t ), t being an integer starting from 0 and incrementing in steps of 1; and
transmission circuitry, which in operation, controls a transmission of the first precoded symbols z 1 ( t ) and the second precoded symbols z 2 ( t ) from different antennas,
wherein the precoding process is expressed by the following Equation 1:
[
z
1
(
t
)
z
2
(
t
)
]
=
1
a
2
+
1
[
e
j
*
0
α
*
e
j
*
0
α
*
e
j
*
θ
e
j
*
(
θ
+
λ
)
]
[
s
1
(
t
)
s
2
(
t
)
]
(
Equation
1
)
θ changes in turn according to t within a period N, θ is a value expressed in radians, λ is a value expressed in radians, and α is a value which is less than 1.
2 . The integrated circuit according to claim 1 , wherein reference signals used for first precoded symbols z 1 ( t ) and the second precoded symbols z 2 are transmitted in a specific frequency.
3 . A integrated circuit comprising:
generation circuitry, which in operation, controls a generation of first precoded symbols z 1 ( t ) and second precoded symbols z 2 ( t ), the first precoded symbols z 1 ( t ) and the second precoded symbols z 2 ( t ) being generated by performing a precoding process on the first modulated symbols s 1 ( t ) and the second modulated symbols s 2 ( t ), t being an integer starting from 0 and incrementing in steps of 1; and
transmission circuitry, which in operation, controls a transmission of the first precoded symbols z 1 ( t ) and the second precoded symbols z 2 ( t ) from different antennas,
wherein the precoding process is expressed by the following Equation 1:
[
z
1
(
t
)
z
2
(
t
)
]
=
1
a
2
+
1
[
1
a
α
*
e
j
*
θ
e
j
*
(
θ
+
λ
)
]
[
s
1
(
t
)
s
2
(
t
)
]
(
Equation
1
)
θ changes in turn according to t within a period N, θ is a value expressed in radians, λ is a value expressed in radians, and α is a value which is less than 1.
4 . The integrated circuit according to claim 3 , wherein reference signals used for first precoded symbols z 1 ( t ) and the second precoded symbols z 2 are transmitted in a specific frequency.