Method for differentially quantizing channel information in multi-antenna wireless systems and system adopting the same

Patent metadata

Field	Value
Publication number	US-9397734-B2
Application number	US-201113639845-A
Country	US
Kind code	B2
Filing date	Apr 6, 2011
Priority date	Apr 6, 2010
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

A method of signal transmission based on differentially quantized channel information in a multi-antenna wireless communication system which can transmit signal to multiple mobile stations simultaneously through multiple transmit antennas includes a main codebook reporting step of each mobile station for quantizing channel correlation information (CCI) using a main-codebook and reporting an index of the main codebook, which corresponds to the quantized CCI, to a base station. A sub-codebook reporting step of each mobile station for quantizing the change of the CCI between the quantization interval using a sub-codebook and reporting an index of the sub-codebook, which corresponds to the quantized CCI change, to a base station. A multi-user eigen-beam transmission step of the base station for generating multiple eigen-beams using the index of the main-codebook or sub-codebook reported from mobile stations and transmitting them to multiple users simultaneously.

First claim

The invention claimed is:

1. A method of signal transmission based on differentially quantized channel information in a multi-antenna wireless communication system which can transmit signal to multiple mobile stations simultaneously through multiple transmit antennas, comprising:
a main codebook reporting step of each mobile station for quantizing channel correlation information (CCI) using a main-codebook and reporting an index of the main codebook, which corresponds to the quantized CCI, to a base station;
a sub-codebook reporting step of each mobile station reducing an amount of information used to report Channel State Information (CSI) to the base station through an uplink by i) quantizing the change of the CCI between the quantization interval using a sub-codebook and ii) reporting an index of the sub-codebook, which corresponds to the quantized CCI change, to the base station; and
a multi-user eigen-beam transmission step of the base station for generating multiple eigen-beams using the index of the main-codebook or sub-codebook reported from mobile stations, and transmitting them, using the multiple transmit antennas of the base station, to multiple users simultaneously,
wherein the sub-codebook reporting step is configured such that the sub-codebook is generated in consideration of the maximum change in the CCI, being calculated by the following Equation 10:
Δρ l,max =ρ l,max ( t )−ρ l ( t−Δt )  [Equation 10]

where Δt denotes the CSI reporting (or quantization) interval, Δτ l,max denotes a range in which the CCI of mobile station l can maximally vary during the CSI reporting (or quantization) period Δt, ρ l (t−Δt) denotes the channel correlation coefficient of mobile station l at the previous quantization time t−Δt, and ρ l,max (t) is calculated by the following Equation 9:

ρ

l
,

m
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⁢
a
⁢

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x

⁡

(
t
)

=

J
0

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(

2
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π
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d
/
λ

)

+

2
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∑

i
=
1

∞

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J

2
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i

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(

2
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π
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d
/
λ

)

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cos
⁡

(

2
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i
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(

Ao
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D
k

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(

t
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Δ
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t

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+

Δ

Ao
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Assignees

• Lee Yong Hwan
• Cho Hee-Nam
• Lee Jin-Woo
• Snu R&Db Foundation

Inventors

• Lee Yong Hwan
• Cho Hee-Nam
• Lee Jin-Woo

Classifications

• H04B7/0481

  using subset selection of codebooks · CPC title

• H04W24/10

  Scheduling measurement reports {; Arrangements for measurement reports} · CPC title

• H04B7/0641

  Differential feedback · CPC title

• H04B7/0647

  Variable feedback rate · CPC title

• H04B7/0434

  using multiple eigenmodes · CPC title