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US 9,362,996 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.
Claims4
A method for generating a plurality of signals and transmitting the plurality of signals from a plurality of antennas in the same frequency at the same time, generation of the plurality of signals comprising:
- 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 a precoding process that is performed on a plurality of baseband signals;
- and
- generating a first precoded signal z1 and a second precoded signal z2 by performing a 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 generated from a first set of bits and a second baseband signal s2 generated from a second set of bits,
- 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 predetermined number of slots, the first precoded signal z1 and the second precoded signal z2 being transmitted from a first antenna and a second antenna respectively in the same frequency at the same time, and the first set of bits and the second set of bits used in one slot not being used in another slot.
66 more elements
An apparatus for generating a plurality of signals and transmitting the plurality of 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], 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 a precoding process that is performed on a plurality of baseband signals;
- and
- a weighting unit configured to generate a first precoded signal z1 and a second precoded signal z2 by performing a 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 generated from a first set of bits and a second baseband signal s2 generated from a second set of bits,
- 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 predetermined number of slots, the first precoded signal z1 and the second precoded signal z2 being transmitted from a first antenna and a second antenna respectively in the same frequency at the same time, and the first set of bits and the second set of bits used in one slot not being used in another slot.
66 more elements
A method comprising:
- 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,
- 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 generated from a first set of bits and a second baseband signal s2 generated from a second set of bits, 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 predetermined number of slots, the first precoded signal z1 and the second precoded signal z2 being transmitted from a first antenna and a second antenna respectively in the same frequency at the same time, and the first set of bits and the second set of bits used in one slot not being used in another slot,
- the method further comprising:
- generating reception data by demodulating the received signal based on the selected matrix at each slot.
65 more elements
An 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,
- 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 generated from a first set of bits and a second baseband signal s2 generated from a second set of bits, 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 predetermined number of slots, the first precoded signal z1 and the second precoded signal z2 being transmitted from a first antenna and a second antenna respectively in the same frequency at the same time, and the first set of bits and the second set of bits used in one slot not being used in another slot,
- the apparatus further comprising:
- a signal processing unit configured to generate reception data by demodulating the received signal based on the selected matrix at each slot.
65 more elements
Dependencies are inferred from the claim text.