RADIO TRANSMITTING APPARATUS, RADIO RECEIVING APPARATUS AND RADIO TRANSMITTING METHOD

• US 20090093265A1
• Filed: 05/25/2006
• Published: 04/09/2009
• Est. Priority Date: 05/25/2005
• Status: Abandoned Application

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Imai, Tomohiro, Kimura, Ryohei, Miyoshi, Kenichi, Yuda, Yasuaki, Hoshino, Masayuki
• Application Number:
  US11/915,375
• Publication Number:
  US 20090093265A1
• Time in Patent Office: Days
• US Class Current: 455/500
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/043 using best eigenmode, e.g. beam forming or beam steering
• CPC Class Codes: H04B 7/0434 using multiple eigenmodes
• CPC Class Codes: H04B 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0632 Channel quality parameters, e.g. channel quality indicator [CQI]
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0015 characterised by the adaptation strategy
• CPC Class Codes: H04L 1/0016 involving special memory structures, e.g. look-up tables
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end

Abstract

A radio transmitting apparatus, a radio receiving apparatus and a radio transmitting method wherein the accuracy of detecting streams in D-TxAA is improved. There is included a transmission mode switching part (102) that switches output destinations of first and second input streams (1865,1866) in accordance with the propagation environments of first and second MIMO channel beams (1831,1832). The transmission mode switching part (102) switches from a D-TxAA mode transmission to a first or second unique mode transmission in accordance with the propagation environments.

Claims

1. A radio transmitting apparatus comprising:

a plurality of transmitting antennas;

a transmission mode determining section that determines one transmission mode of an eigen mode transmission using the plurality of transmitting antennas and a double transmit antenna array mode transmission, based on information fed back from a communicating party; and

a transmitting section that transmits streams by switching to the determined transmission mode.

2. The radio transmitting apparatus according to claim 1, wherein, based on channel environment information of streams comprising the fed back information, the transmission mode determining section determines the double transmit antenna array mode transmission when a quality difference between streams transmitted from subgroup antennas is less than a predetermined threshold value and determines eigen mode transmission using subgroup antennas having high quality when the quality difference is equal to or greater than the predetermined threshold value.

3. The radio transmitting apparatus according to claim 1, wherein the channel environment information comprises one of a multi-input multi-output channel matrix, a received signal to interference and noise ratio, and an eigenvalue.

4. The radio transmitting apparatus according to claim 1, wherein the transmission mode determining section determines a transmission mode according to a transmission mode comprising the fed back information.

5. The radio transmitting apparatus according to claim 4, wherein the transmission mode comprising the fed back information is one of a first eigen mode transmission using a first eigenvalue, a second eigen mode transmission using the second eigenvalue and the double transmit antenna array mode transmission, the first eigenvalue and a second eigenvalue being calculated from the multi-input multi-output channel matrix.

6. The radio transmitting apparatus according to claim 1, wherein the transmission mode determining section determines a transmission mode different from a previous transmission mode per retransmission.

7. A radio receiving apparatus comprising:

a transmission mode determining section that determines one transmission mode of an eigen mode transmission using a plurality of transmitting antennas and a double transmit antenna array mode transmission, based on a propagation environment; and

a feedback section that feeds back the determined transmission mode to a communicating party.

8. A radio transmission method comprising:

a transmission mode determining step of determining one transmission mode of an eigen mode transmission using a plurality of transmitting antennas and a double transmit antenna array mode transmission, based on information fed back from a communicating party; and

a transmitting step of transmitting streams by switching to the determined transmission mode.