Closed Loop Mimo Systems And Methods

Patent metadata

Field	Value
Publication number	US-2016134339-A1
Application number	US-201615000542-A
Country	US
Kind code	A1
Filing date	Jan 19, 2016
Priority date	Jun 22, 2004
Publication date	May 12, 2016
Grant date	—

Abstract

Systems and methods for closed loop MIMO (multiple input and multiple output) wireless communication are provided. Various transmit formats including spatial multiplexing and STTD are defined in which vector or matrix weighting is employed using information fed back from receivers. The feedback information may include channel matrix or SVD-based feedback.

First claim

1 - 24 . (canceled)

25 . A multiple input multiple output (MIMO) system comprising:
a receiver having at least one receive antenna, wherein the receiver is configured to:
analyze one or more channel conditions of a communication with a transmitter having a plurality of transmit antennas;
based on the one or more channel conditions, select a spatial-multiplexing (SM) format for transmission in the communication and one or more transmission layers for use in the transmission, wherein the SM format is a selection of one of the defined subset of available formats; and
generate, for transmission to the transmitter, feedback information specifying the selected SM format and the number of selected transmission layers.

26 . The system of claim 25 , wherein the receiver is configured to:
based on one or more channel conditions, select a space time transmit diversity (STTD) format for the transmission and a grouping of the plurality of antennas for use in the transmission; and generate, for transmission to the transmitter, feedback information specifying the selected STTD format and the grouping of the plurality of antennas.

27 . The system of claim 25 , wherein the transmitter comprises four antennas.

28 . The system of claim 25 , wherein the transmission layers are layer based water-filling.

29 . The system of claim 25 , wherein a first pair of the transmitter antennas are assigned to a first stream, and a second pair of the transmitter antennas are assigned to a second stream, at least one of the transmission layers is transmitted on either the first pair or the second pair of antennas.

30 . The system of claim 25 , wherein the feedback information specifies beam-forming information usable by the transmitter.

31 . The system of claim 25 , wherein more power is transmitted to the transmission layer having better channel conditions.

32 . A method for transmitting via a receiver, comprising:
analyzing one or more channel conditions of a communication with a transmitter having a plurality of transmit antennas; based on the one or more channel conditions, selecting a spatial-multiplexing (SM) format for transmission in the communication and one or more transmission layers for use in the transmission, wherein the SM format is a selection of one of the defined subset of available formats; and generating, for transmission to the transmitter, feedback information specifying the selected SM format and the number of selected transmission layers.

33 . The method of claim 32 , wherein,
based on one or more channel conditions, selecting a space time transmit diversity (STTD) format for the transmission and a grouping of the plurality of antennas for use in the transmission; and generating, for transmission to the transmitter, feedback information specifying the selected STTD format and the grouping of the plurality of antennas.

34 . The method of claim 32 , wherein the transmission layers are layer based water-filling.

35 . The method of claim 32 , wherein the transmitter comprises four antennas.

36 . The method of claim 32 , wherein a first pair of the transmitter antennas are assigned to a first stream, and a second pair of the transmitter antennas are assigned to a second stream, at least one of the transmission layers is transmitted on either the first pair or the second pair of antennas.

37 . The method of claim 32 , wherein the feedback information specifies beam-forming information usable by the transmitter.

38 . The method of claim 32 , wherein more power is transmitted to the transmission layer having better channel conditions.

39 . A non-transitory computer-readable storage medium with an executable program stored thereon, wherein the program instructs a processor to perform operations comprising:
analyzing one or more channel conditions of a communication with a transmitter having a plurality of transmit antennas; based on the one or more channel conditions, selecting a spatial-multiplexing (SM) format for transmission in the communication and one or more transmission layers for use in the transmission, wherein the SM format is a selection of one of the defined subset of available formats; and generating, for transmission to the transmitter, feedback information specifying the selected SM format and the number of selected transmission layers.

40 . The non-transitory computer-readable storage medium of claim 39 , wherein the operations further comprise:
based on one or more channel conditions, selecting a space time transmit diversity (STTD) format for the transmission and a grouping of the plurality of antennas for use in the transmission; and generating, for transmission to the transmitter, feedback information specifying the selected STTD format and the grouping of the plurality of antennas.

41 . The non-transitory computer-readable storage medium of claim 39 , wherein the transmission layers are layer based water-filling

42 . The non-transitory computer-readable storage medium of claim 39 , wherein the transmitter comprises four antennas.

43 . The non-transitory computer-readable storage medium of claim 39 , wherein a first pair of the transmitter antennas are assigned to a first stream, and a second pair of the transmitter antennas are assigned to a second stream, at least one of the transmission layers is transmitted on either the first pair or the second pair of antennas.

44 . The non-transitory computer-readable storage medium of claim 39 , wherein the feedback information specifies beam-forming information usable by the transmitter.

Assignees

• Apple Inc

Inventors

• Tong Wen
• Jia Ming
• Ma Jianglei
• Zhu Peiying
• Xu Hua
• Yu Dong-Sheng
• Zhang Hang
• Fong Mo-Han

Classifications

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W72/54

  based on quality criteria · CPC title

• H04L5/005

  of common pilots, i.e. pilots destined for multiple users or terminals · CPC title

• H04W48/08

  Access restriction or access information delivery, e.g. discovery data delivery (signalling during connection H04W76/00) · CPC title

• H04L27/2601

  Multicarrier modulation systems · CPC title