TERMINAL STATION APPARATUS, BASE STATION APPARATUS, TRANSMISSION METHOD AND CONTROL METHOD

• US 20120170444A1
• Filed: 09/30/2010
• Published: 07/05/2012
• Est. Priority Date: 10/01/2009
• Status: Active Grant

• Current Assignee: Sun Patent Trust
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Ogawa, Yoshihiko, Nishio, Akihiko, Iwai, Takashi, Nakao, Seigo, Imamura, Daichi, Sumasu, Atsushi
• Granted Patent: US 8,917,587 B2
• Time in Patent Office: Days
• US Class Current: 370/209
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04J 11/003 at the transmitter transmission to multiple receive units in multiple input multiple output [MIMO] H04B7/0452; transmit antenna weighting H04B7/0615
• CPC Class Codes: H04J 13/0048 Walsh
• CPC Class Codes: H04J 13/18 Allocation of orthogonal codes
• CPC Class Codes: H04L 5/005 of common pilots, i.e. pilots destined for multiple users or terminals
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/54 based on quality criteria
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A terminal apparatus is disclosed wherein even in a case of applying SU-MIMO and MU-MIMO at the same time, the inter-sequence interference in a plurality of pilot signals used by the same terminal can be suppressed to a low value, while the inter-sequence interference in pilot signal between terminals can be reduced. In this terminal apparatus (200): a pilot information deciding unit (204) decides, based on allocation control information, Walsh sequences of the respective ones of first and second stream groups at least one of which includes a plurality of streams; and a pilot signal generating unit (205) forms a transport signal by using the decided Walsh sequences to spread the streams included in the first and second stream groups. During this, Walsh sequences orthogonal to each other are established in the first and second stream groups, and users are allocated on a stream group-by-stream group basis.

Claims

1. A terminal station apparatus comprising:

a reception section that receives assignment control information reported with downlink resources;

a determining section that determines Walsh sequences of first and second stream groups at least one of which includes a plurality of streams based on the assignment control information;

a formation section that forms a transmission signal by spreading each stream included in the first and second stream groups using the determined Walsh sequences; and

a transmission section that transmits the formed transmission signal, wherein mutually orthogonal Walsh sequences are set in the first and second stream groups respectively and users are assigned in the stream group units.

2. The terminal station apparatus according to claim 1, wherein:

the apparatus comprises a multiuser MIMO mode and a single user MIMO mode;

in the multiuser MIMO, the first and second stream groups are assigned to different users respectively; and

in the single user MIMO, the first and second stream groups are assigned to a single user.

3. The terminal station apparatus according to claim 1, wherein a stream number indicating order in which data signals are assigned is associated with the stream and the stream numbers of the plurality of streams included in the first or second stream group are continuous.

4. The terminal station apparatus according to claim 1, wherein the formation section comprises:

a first spreading section that spreads streams included in the first and second stream groups using any one of a plurality of cyclic shift sequences which are mutually separable according to different cyclic shift amounts; and

a second spreading section that spread the streams spread with the cyclic shift sequences using the Walsh sequences,

wherein the determining section determines the cyclic shift sequences and the Walsh sequences, based on first instruction information instructing the cyclic shift amount included in the assignment control information and an operating sequence identification table storing pairs of the cyclic shift amount and the Walsh sequence.

5. The terminal station apparatus according to claim 4, wherein:

the operating sequence identification table stores candidates for pairs of the cyclic shift amount and the Walsh sequence;

the determining section switches between the pairs of the cyclic shift amount and the Walsh sequence, based on second instruction information instructing candidates for the pair included in the assignment control information; and

a reception cycle of the second instruction information is longer than a reception cycle of the first instruction information.

6. The terminal station apparatus according to claim 4, wherein of the pairs of the cyclic shift amount and the Walsh sequence included in the operating sequence identification table, pairs of first Walsh sequences whose all elements are composed of “

1”

s are fewer than pairs other than pairs of the first Walsh sequences.

7. The terminal station apparatus according to claim 4, wherein in the operating sequence identification table, the Walsh sequences paired with the neighboring cyclic shift amounts are different.

8. The terminal station apparatus according to claim 4, wherein in the operating sequence identification table, with respect to a pair of a first cyclic shift amount and a second cyclic shift amount corresponding to a maximum cyclic shift amount interval, a Walsh sequence associated with the first cyclic shift amount is the same as a Walsh sequence associated with the second cyclic shift amount.

9. The terminal station apparatus according to claim 4, wherein in the operating sequence identification table, with respect to a pair of a first cyclic shift amount and a second cyclic shift amount corresponding to a maximum cyclic shift amount interval, a Walsh sequence associated with the first cyclic shift amount is different from a Walsh sequence associated with the second cyclic shift amount.

10. The terminal station apparatus according to claim 4, wherein in the operating sequence identification table, in a plurality of cyclic shift amount groups made up of cyclic shift amounts whose a cyclic shift amount interval is ½

of a maximum value of the cyclic shift amount interval, the Walsh sequence associated with a cyclic shift amount included in a first cyclic shift amount group is a first Walsh sequence, a Walsh sequence associated with a cyclic shift amount included in a second cyclic shift amount group is a second Walsh sequence and Walsh sequences associated with a cyclic shift amount included in a third cyclic shift amount group are the first and second Walsh sequences.

11. A base station apparatus comprising:

a control section that sets mutually orthogonal Walsh sequences in first and second stream groups at least one of which includes a plurality of streams and assigns users in the stream group units; and

a transmission section that transmits assignment control information indicating the Walsh sequence set in the first or second stream group.

12. The base station apparatus according to claim 11, wherein a multiuser MIMO mode and a single user MIMO mode are mixed in uplink resources,

wherein the control section assigns the first and second stream groups to different users respectively in the multiuser MIMO, and

assigns the first and second stream groups to a single user in the single user MIMO.

13. The base station apparatus according to claim 11, wherein stream numbers indicating order in which data signals are assigned are associated with the streams and the stream numbers of the plurality of streams included in the first or second stream group are continuous.

14. A transmission method comprising:

a reception step of receiving assignment control information transmitted with downlink resources;

a determining step of determining Walsh sequences of first and second stream groups at least one of which includes a plurality of streams based on the assignment control information;

a forming step of forming a transmission signal by spreading streams included in the first or second stream group using the determined Walsh sequences; and

a transmission step of transmitting the formed transmission signal,

wherein mutually orthogonal Walsh sequences are set in the first and second stream groups respectively and users are assigned in the stream group units.

15. A control method comprising:

a control step of setting mutually orthogonal Walsh sequences in first and second stream groups at least one of which includes a plurality of streams and assigning users in the stream group units; and

a transmission step of transmitting assignment control information indicating the Walsh sequences set in the first or second stream group.