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US 9,843,368 B2Granted
Pre-coding method and transmitter
AssigneeSun Patent Trust
InventorsYutaka Murakami, Tomohiro Kimura, Mikihiro Ouchi
Life of this patent
Estimating the term…
Abstract
Disclosed is a transmission scheme for transmitting a first modulated signal and a second modulated signal over the same frequency at the same time. According to the transmission scheme, a precoding weight multiplying unit multiplies a baseband signal after a first mapping and a baseband signal after a second mapping by a precoding weight and outputs the first modulated signal and the second modulated signal. In the precoding weight multiplying unit, precoding weights are regularly hopped.
Claims6
A transmission method, comprising:
- selecting whether to perform a precoding process;
- selecting one matrix from among N matrices F[i], wherein i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater, by hopping between the matrices over each of a plurality of slots, the N matrices F[i] defining the precoding process that is performed on a plurality of baseband signals when the precoding process is performed;
- generating a first precoded signal z1 and a second precoded signal z2 by performing the precoding process, which corresponds to the matrix selected from among the N matrices F[i], over each of the plurality of slots on a first baseband signal s1 included in the plurality of baseband signals, a second baseband signal s2 included in the plurality of baseband signals and a result of the selecting whether to perform the precoding;
- and
- transmitting the first precoded signal z1, and the second precoded signal z2 being transmitted from a first transmission antenna and a second transmission antenna respectively in the same frequency at the same time when the precoding process is performed, wherein
- the first precoded signal z1 and the second precoded signal z2 satisfying (z1, z2)T=F[i] (s1, s2)T,
- the N matrices F[i] being expressed as:
- 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
- )
- )
- λ representing an arbitrary angle, α representing a positive real number, θ11(i) and θ21(i) satisfying:
- ej(θ11(x)−θ21(x))≠ej(θ11(y)−θ21(y))
- x and y are any integers no less than 0 and no more than N−1 satisfying x≠y,
- each of the N matrices being selected at least once in a determined number of slots.
68 more elements
A transmission apparatus comprising:
- selection circuitry, which in operation, selects whether to perform a precoding process;
- weighting information generation circuitry, which in operation, selects one matrix from among N matrices F[i], wherein i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater, by hopping between the matrices over each of a plurality of slots, the N matrices F[i] defining the precoding process that is performed on a plurality of baseband signals when the precoding process is performed;
- weighting circuitry, which in operation, generates a first precoded signal z1 and a second precoded signal z2 by performing the precoding process, which corresponds to the matrix selected from among the N matrices F[i], over said each of the plurality of slots on a first baseband signal s1 included in the plurality of baseband signals, a second baseband signal s2 included in the plurality of baseband signals and a result of the selecting whether to perform the precoding;
- and
- transmission circuitry, which in operation, transmits the first precoded signal z1, and the second precoded signal z2 from a first transmission antenna and a second transmission antenna respectively in the same frequency at the same time, wherein
- the first precoded signal z1 and the second precoded signal z2 satisfying (z1, z2)T=F[i] (s1, s2)T,
- the N matrices F[i] being expressed as:
- 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
- )
- )
- λ representing an arbitrary angle, α representing a positive real number, θ11(i) and θ21(i) satisfying:
- ej(θ11(x)−θ21(x))≠ej(θ11(y)−θ21(y))
- wherein x and y are any integers no less than 0 and no more than N−1 satisfying x≠y,
- each of the N matrices being selected at least once in a determined number of slots.
68 more elements
A reception method comprising:
- receiving a plurality of signals transmitted from a plurality of transmission antennas in the same frequency at the same time;
- acquiring a received signal and a result of the selecting whether to perform the precoding obtained from the plurality of signals;
- and
- generating reception data by demodulating the received signal based on the selecting whether to perform the precoding, wherein
- the plurality of signals being transmitted based on a first precoded signal z1 and a second precoded signal z2 that are generated from a first baseband signal s1 and a second baseband signal s2 respectively, the first baseband signal s1 and the second baseband signal s2 being precoded over each of a plurality of slots by a precoding process that corresponds to a matrix selected from among N matrices F[i] by hopping between the matrices over each of the plurality of slots, wherein i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater, the first precoded signal z1 and the second precoded signal z2 satisfying (z1, z2)T=F[i] (s1, s2)T, the N matrices F[i] being expressed as:
- 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
- )
- )
- λ representing an arbitrary angle, α representing a positive real number, θ11(i) and θ21(i) satisfying:
- ej(θ11(x)−θ21(x))≠ej(θ11(y)−θ21(y))
- x and y are any integers no less than 0 and no more than N−1 satisfying x≠y,
- each of the N matrices being selected at least once in a determined number of slots.
66 more elements
A reception apparatus comprising:
- reception circuitry, which in operation, receives a plurality of signals transmitted from a plurality of transmission antennas in the same frequency at the same time;
- received signal acquisition circuitry, which in operation, acquires a received signal and a result of the selecting whether to perform the precoding obtained from the plurality of signals;
- signal processing circuitry, which in operation, generates reception data by demodulating the received signal based on the selecting whether to perform the precoding, wherein
- the plurality of signals being transmitted based on a first precoded signal z1 and a second precoded signal z2 that are generated from a first baseband signal s1 and a second baseband signal s2 respectively, the first baseband signal s1 and the second baseband signal s2 being precoded over each of a plurality of slots by a precoding process that corresponds to a matrix selected from among N matrices F[i] by hopping between the matrices over each of the plurality of slots, wherein i is an integer no less than 0 and no more than N−1, and N is an integer 3 or greater, the first precoded signal z1 and the second precoded signal z2 satisfying (z1, z2)T=F[i] (s1, s2)T, the N matrices F[i] being expressed as:
- 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
- )
- )
- λ representing an arbitrary angle, α representing a positive real number, θ11(i) and θ21(i) satisfying:
- ej(θ11(x)−θ21(x))≠ej(θ11(y)−θ21(y))
- wherein x and y are any integers no less than 0 and no more than N−1 satisfying x≠y,
- each of the N matrices being selected at least once in a determined number of slots.
65 more elements
Dependencies are inferred from the claim text.