Base station apparatus and resource allocation method

• US 9,462,588 B2
• Filed: 09/22/2015
• Issued: 10/04/2016
• Est. Priority Date: 11/14/2008
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Sun Patent Trust
• Inventors: Takaoka, Shinsuke, Nakao, Seigo, Imamura, Daichi, Hoshino, Masayuki
• Primary Examiner(s): Kassim, Khaled
• Assistant Examiner(s): ALI, SYED
• Application Number:
  US14/861,860
• Publication Number:
  US 20160014783A1
• Time in Patent Office: 378 Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04J 13/0059 CAZAC [constant-amplitude and zero auto-correlation]
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453
• CPC Class Codes: H04L 27/2636 with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0021 in which codes are applied as a frequency-domain sequences, e.g. MC-CDMA
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0041 Frequency-non-contiguous
• CPC Class Codes: H04L 5/0046 Determination of how many bits are transmitted on different sub-channels
• CPC Class Codes: H04L 5/006 Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A wireless communication terminal apparatus wherein even when a SC-FDMA signal is divided into a plurality of clusters and the plurality of clusters are then mapped to respective discontinuous frequency bands (when C-SC-FDMA is used), the improvement effect of system throughput can be maintained, while the user throughput can be improved. In the apparatus, a DFT unit (210) subjects a symbol sequence of time domain to a DFT process, thereby generating signals of frequency domain. A setting unit (211) divides the signals input from the DFT unit (210) into a plurality of clusters according to a cluster pattern that is in accordance with an MCS set, an encoding size, or the number of Ranks occurring during MIMO transmissions, which is indicated in those signals input, and then maps the plurality of clusters to the respective ones of a plurality of discontinuous frequency resources, thereby setting a constellation of the plurality of clusters in the frequency domain.

Claims

1. A communication apparatus comprising:

a discrete Fourier transformer which, in operation, performs Fourier transformations (DFTs) on a plurality of symbol sequences, each symbol sequence corresponding to one of a plurality of layers, wherein the plurality of symbol sequences comprise different code words from each other and a number of the plurality of layers is at least as large as a number of the different code words;

a precoder which, in operation, generates a plurality of precoded symbol sequences based on the plurality of DFT performed symbol sequences and a precoding matrix; and

a mapper which, in operation, maps each of the plurality of precoded symbol sequences on a same set of discontinuous frequency resources, each frequency resource being located on a separate position from other frequency resources on a frequency axis, wherein the same set of discontinuous frequency resources means that a first set of discontinuous frequency resources, to which a first precoded symbol sequence is mapped, and a second set of discontinuous frequency resources, to which a second precoded symbol sequence is mapped, share at least one of a number of clusters, cluster sizes, and a frequency position of each of the clusters in common, a cluster size being a frequency bandwidth of the discontinuous frequency resource.

2. The communication apparatus according to claim 1 wherein the cluster size is defined according to a minimum cluster size.

3. The communication apparatus according to claim 1, wherein a rank indicator identifying a number of the plurality of layers is equal to or less than a number of antennas provided at the communication apparatus.

4. The communication apparatus according to claim 1 wherein when a plurality of code words are used, the plurality of precoded symbol sequences derives from a plurality of first symbol sequences corresponding to a first code word and a plurality of second symbol sequences corresponding to a second code word which is different from the first code word.

5. The communication apparatus of claim 1 wherein the first set of discontinuous frequency resources comprises a first cluster having a first cluster size and a second cluster having a second cluster size.

6. A communication method, performed by a communication apparatus, the method comprising:

performing discrete Fourier transformations (DFT) on a plurality of symbol sequences, each symbol sequence corresponding to one of a plurality of layers, wherein the plurality of symbol sequences comprise different code words from each other and a number of the plurality of layers is at least as large as a number of the different code words;

generating a plurality of precoded symbol sequences based on the plurality of DFT performed symbol sequences and a precoding matrix; and

mapping each of the plurality of precoded symbol sequences on a same set of discontinuous frequency resources, each frequency resource being located on a separate position from other frequency resources on a frequency axis, wherein the same set of discontinuous frequency resources means that a first set of discontinuous frequency resources, to which a first precoded symbol sequence is mapped, and a second set of discontinuous frequency resources, to which a second precoded symbol sequence is mapped, share at least one of a number of clusters, cluster sizes, and a frequency position of each of the clusters in common, a cluster size being a frequency bandwidth of the discontinuous frequency resource.

7. The communication method according to claim 6 wherein the cluster size is defined according to a minimum cluster size.

8. The communication method according to claim 6, wherein a rank indicator identifying a number of the plurality of layers is equal to or less than a number of antennas provided at the terminal apparatus.

9. A communication apparatus comprising:

a discrete Fourier transformer which, in operation, performs Fourier transformations (DFTs) on a plurality of symbol sequences, each symbol sequence corresponding to one of a plurality of layers, wherein the plurality of symbol sequences comprise different code words from each other and a number of the plurality of layers is at least as large as a number of the different code words;

a precoder which, in operation, generates a plurality of precoded symbol sequences based on a plurality of DFT performed symbol sequences and a precoding matrix; and

a mapper which, in operation, maps each of the plurality of precoded symbol sequences to a plurality of frequency resources, each of the plurality of frequency resources being located on a separate position from other frequency resources on a frequency axis, wherein a first plurality of frequency resources to which a first precoded symbol sequence is mapped, and a second plurality of frequency resources to which a second precoded symbol sequence is mapped share;

a number of frequency resources used to map each precoded symbol sequence;

a size; and

a frequency position of each of the frequency resources, the size being a frequency resource bandwidth.

10. The communication apparatus according to claim 9, wherein

when a number of code words is smaller than a number of the layers, the plurality of precoded symbol sequences derives from a plurality of symbol sequences corresponding to a same code word.

11. The communication apparatus according to claim 9, wherein

when a plurality of code words are used, the plurality of precoded symbol sequences derives from a plurality of first symbol sequences corresponding to a first code word and a plurality of second symbol sequences corresponding to a second code word which is different from the first code word.

12. The communication apparatus according to claim 11, wherein

a number of layers corresponding to the first codeword is equal to a number of layers corresponding to the second codeword.

13. A communication method performed by a communication apparatus, the method comprising:

performing discrete Fourier transformations (DFT) on a plurality of symbol sequences, each symbol sequence corresponding to one of a plurality of layers, wherein the plurality of symbol sequences comprise different code words from each other and a number of the plurality of layers is at least as large as a number of the different code words;

generating a plurality of precoded symbol sequences based on the plurality of DFT performed symbol sequences and a precoding matrix; and

mapping each of the plurality of precoded symbol sequences to a plurality of frequency resources, each of the plurality of frequency resources being located on a separate position from other frequency resources on a frequency axis, wherein a first plurality of frequency resources to which a first precoded symbol sequence is mapped, and a second plurality of frequency resources to which a second precoded symbol sequence is mapped share;

a number of frequency resources used to map each precoded symbol sequence;

a size; and

a frequency position of each of the frequency resources, the size being a frequency resource bandwidth.

14. The communication method according to claim 13, wherein

when a number of code words is smaller than a number of the layers, the plurality of precoded symbol sequences derives from a plurality of symbol sequences corresponding to a same code word.

15. The communication method according to claim 13, wherein

when a plurality of code words are used, the plurality of precoded symbol sequences derives from a plurality of first symbol sequences corresponding to a first code word and a plurality of second symbol sequences corresponding to a second code word which is different from the first code word.

16. The communication method according to claim 13, wherein

a number of layers corresponding to the first code word is equal to a number of layers corresponding to the second code word.