Precoding method, precoding device
View Patent ↗Disclosed is a precoding method for generating, from a plurality of baseband signals, a plurality of precoded signals that are transmitted in the same frequency bandwidth at the same time. According to the precoding method, one matrix is selected from among matrices defining a precoding process that is performed on the plurality of baseband signals by hopping between the matrices. A first baseband signal and a second baseband signal relating to a first coded block and a second coded block generated by using a predetermined error correction block coding scheme satisfy a given condition.
1. A transmission method for generating a plurality of transmission signals and transmitting the plurality of transmission signals from a plurality of antennas in the same frequency at the same time, the transmission method comprising, in the generation of the plurality of transmission signals, the steps of:
selecting one matrix from among N matrices F[i] by hopping between the matrices, for each of a plurality of slots, where i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater, the N matrices F[i] each defining a precoding process that is performed on a plurality of baseband signals;
generating a first coded block and a second coded block from transmission data by using a predetermined error correction block coding scheme;
performing a precoding process that corresponds to the selected matrix on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in the first coded block, thereby generating a first precoded signal z 1 and a second precoded signal z 2 ; and
performing a precoding process that corresponds to the selected matrix on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in the second coded block, thereby generating a first precoded signal z 1 and a second precoded signal z 2 , wherein
the first precoded signals z 1 and the second precoded signals z 2 satisfy (z 1 , z 2 ) T =F[i] (s 1 , s 2 ) T ,
the N matrices F[i] satisfy:
F
[
i
]
=
1
α
2
+
1
(
ⅇ
jθ
11
(
i
)
α
×
ⅇ
j
(
θ
11
(
i
)
+
λ
)
α
×
ⅇ
jθ
21
(
i
)
ⅇ
j
(
θ
21
(
i
)
+
λ
+
π
)
)
where λ represents an arbitrary angle, α represents a positive real number other than 1, θ 11 (i) and θ 21 (i) satisfy:
e j(θ 11 (x)−θ 21 (x)) ≠e j(θ 11 (y)−θ 21 (y))
where x and y are any integers no less than 0 and no more than N−1 satisfying x≠y, and
a matrix selected for the first slot in the first coded block is the same as a matrix selected for the first slot in the second coded block.
2. A transmission apparatus for generating a plurality of transmission signals and transmitting the plurality of transmission signals from a plurality of antennas in the same frequency at the same time, the transmission apparatus comprising:
a weighting information generating unit configured to select one matrix from among N matrices F[i] by hopping between the matrices, for each of a plurality of slots, where i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater, the N matrices F[i] each defining a precoding process that is performed on a plurality of baseband signals;
an error correction coding unit configured to generate a first coded block and a second coded block from transmission data by using a predetermined error correction block coding scheme; and
a weighting unit configured to
perform a precoding process that corresponds to the selected matrix on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in the first coded block, thereby generating a first precoded signal z 1 and a second precoded signal z 2 ; and
perform a precoding process that corresponds to the selected matrix on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in the second coded block, thereby generating a first precoded signal z 1 and a second precoded signal z 2 , wherein
the first precoded signals z 1 and the second precoded signals z 2 satisfy (z 1 , z 2 ) T =F[i] (s 1 , s 2 ) T ,
the N matrices F[i] satisfy:
F
[
i
]
=
1
α
2
+
1
(
ⅇ
jθ
11
(
i
)
α
×
ⅇ
j
(
θ
11
(
i
)
+
λ
)
α
×
ⅇ
jθ
21
(
i
)
ⅇ
j
(
θ
21
(
i
)
+
λ
+
π
)
)
where λ represents an arbitrary angle, α represents a positive real number other than 1, θ 11 (i) and θ 21 (i) satisfy:
e j(θ 11 (x)−θ 21 (x)) ≠e j(θ 11 (y)−θ 21 (y))
where x and y are any integers no less than 0 and no more than N−1 satisfying x≠y, and
a matrix selected for the first slot in the first coded block is the same as a matrix selected for the first slot in the second coded block.
3. A reception method comprising the step of:
acquiring a received signal obtained by receiving a plurality of signals transmitted from a plurality of antennas in the same frequency at the same time, wherein
the plurality of signals include:
a signal being transmitted based on a first precoded signal z 1 and a second precoded signal z 2 that are generated by performing a precoding process that uses one matrix selected from among N matrices F[i] by hopping between the matrices, for each of a plurality of slots, on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in a first coded block, where i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater; and
a signal being transmitted based on a first precoded signal z 1 and a second precoded signal z 2 that are generated by performing a precoding process that uses one matrix selected from among the N matrices F[i] by hopping between the matrices, for each of a plurality of slots, on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in a second coded block, where i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater,
the first coded block and the second coded block are generated from transmission data by using a predetermined error correction block coding scheme,
the first precoded signals z 1 and the second precoded signals z 2 satisfy (z 1 , z 2 ) T =F[i] (s 1 , s 2 ) T ,
the N matrices F[i] satisfy:
F
[
i
]
=
1
α
2
+
1
(
ⅇ
jθ
11
(
i
)
α
×
ⅇ
j
(
θ
11
(
i
)
+
λ
)
α
×
ⅇ
jθ
21
(
i
)
ⅇ
j
(
θ
21
(
i
)
+
λ
+
π
)
)
where λ represents an arbitrary angle, α represents a positive real number other than 1, θ 11 (i) and θ 21 (i) satisfy:
e j(θ 11 (x)−θ 21 (x)) ≠e j(θ 11 (y)−θ 21 (y))
where x and y are any integers no less than 0 and no more than N−1 satisfying x≠y, and
a matrix selected for the first slot in the first coded block is the same as a matrix selected for the first slot in the second coded block.
4. A reception apparatus comprising:
a received signal acquisition unit configured to acquire a received signal obtained by receiving a plurality of signals transmitted from a plurality of antennas in the same frequency at the same time, wherein
the plurality of signals include:
a signal being transmitted based on a first precoded signal z 1 and a second precoded signal z 2 that are generated by performing a precoding process that uses one matrix selected from among N matrices F[i] by hopping between the matrices, for each of a plurality of slots, on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in a first coded block, where i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater; and
a signal being transmitted based on a first precoded signal z 1 and a second precoded signal z 2 that are generated by performing a precoding process that uses one matrix selected from among the N matrices F[i] by hopping between the matrices, for each of a plurality of slots, on a first baseband signal s 1 and a second baseband signal s 2 generated from a plurality of bits included in a second coded block, where i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater,
the first coded block and the second coded block are generated from transmission data by using a predetermined error correction block coding scheme,
the first precoded signals z 1 and the second precoded signals z 2 satisfy (z 1 , z 2 ) T =F[i] (s 1 , s 2 ) T ,
the N matrices F[i] satisfy:
F
[
i
]
=
1
α
2
+
1
(
ⅇ
jθ
11
(
i
)
α
×
ⅇ
j
(
θ
11
(
i
)
+
λ
)
α
×
ⅇ
jθ
21
(
i
)
ⅇ
j
(
θ
21
(
i
)
+
λ
+
π
)
)
where λ represents an arbitrary angle, α represents a positive real number other than 1, θ 11 (i) and θ 21 (i) satisfy:
e j(θ 11 (x)−θ 21 (x)) ≠e j(θ 11 (y)−θ 21 (y))
where x and y are any integers no less than 0 and no more than N−1 satisfying x≠y, and
a matrix selected for the first slot in the first coded block is the same as a matrix selected for the first slot in the second coded block.