講演抄録/キーワード |
講演名 |
2013-05-17 10:10
Benefits of Channel Diagonal Dominance to Cooperative MIMO Systems ○Oussama Souihli・Yasuyuki Hatakawa・Satoshi Konishi(KDDI R&D Labs) RCS2013-31 |
抄録 |
(和) |
In cooperative multiple-input multiple-output (MIMO) cellular systems, a primary base station (BS), typically serving the cell to which the mobile station (MS) identifies, cooperates with K 1 secondary BSs, typically
serving neighboring cells, to efficiently transmit data to a given cell-edge MS. Because achieving the capacity of a general MIMO channel is contingent upon the availability of channel state information (CSI) at the transmitter(s), cooperative MIMO schemes in the literature require K + 1 CSI feedback transmissions from the receiver (one to each of the K + 1 BSs), a signaling overhead that has been argued to be too costly to be worthwhile . Contrarily in this work, we propose the first capacity-approaching cooperative MIMO scheme where the CSI feedback cost is as little as in a point-to-point scenario: Only 1 CSI feedback (that to the primary BS). The proposed scheme is motivated by the fact that if the MIMO channel matrix is diagonally-dominant, CSI-blind uniform-power transmission and receive-side zero-forcing are optimal [Ginis & Cioffi, 2002]. Precisely, in the proposed scheme all K secondary BSs send the
intended signal vector without precoding, whereas only the primary BS applies closed-loop MIMO precoding (such as beamforming) based on CSI (be it full or quantized (codebook-based)) fed back from the MS. Then, the primary BS applies a scaling factor to the precoded vector prior to transmission. This scalar is carefully designed such that the equivalent channel matrix at the receiver?s side is diagonally dominant with probability arbitrarily close to 1, irrespective of the instantaneous realizations of the channels relative to the secondary BSs. Owing to this diagonal dominance, it is shown that simple zero forcing at the receiver?s side suffices to achieve near-optimal signal detection. Even better, depending on the SNR regime, diagonal dominance need not be guaranteed all the time. The proposed cooperative MIMO scheme may find application in the 3GPP LTE-Advanced standard as a Coordinated Multi-Point (CoMP) transmission method. |
(英) |
In cooperative multiple-input multiple-output (MIMO) cellular systems, a primary base station (BS), typically serving the cell to which the mobile station (MS) identifies, cooperates with K 1 secondary BSs, typically
serving neighboring cells, to efficiently transmit data to a given cell-edge MS. Because achieving the capacity of a general MIMO channel is contingent upon the availability of channel state information (CSI) at the transmitter(s), cooperative MIMO schemes in the literature require K + 1 CSI feedback transmissions from the receiver (one to each of the K + 1 BSs), a signaling overhead that has been argued to be too costly to be worthwhile . Contrarily in this work, we propose the first capacity-approaching cooperative MIMO scheme where the CSI feedback cost is as little as in a point-to-point scenario: Only 1 CSI feedback (that to the primary BS). The proposed scheme is motivated by the fact that if the MIMO channel matrix is diagonally-dominant, CSI-blind uniform-power transmission and receive-side zero-forcing are optimal [Ginis & Cioffi, 2002]. Precisely, in the proposed scheme all K secondary BSs send the
intended signal vector without precoding, whereas only the primary BS applies closed-loop MIMO precoding (such as beamforming) based on CSI (be it full or quantized (codebook-based)) fed back from the MS. Then, the primary BS applies a scaling factor to the precoded vector prior to transmission. This scalar is carefully designed such that the equivalent channel matrix at the receiver?s side is diagonally dominant with probability arbitrarily close to 1, irrespective of the instantaneous realizations of the channels relative to the secondary BSs. Owing to this diagonal dominance, it is shown that simple zero forcing at the receiver?s side suffices to achieve near-optimal signal detection. Even better, depending on the SNR regime, diagonal dominance need not be guaranteed all the time. The proposed cooperative MIMO scheme may find application in the 3GPP LTE-Advanced standard as a Coordinated Multi-Point (CoMP) transmission method. |
キーワード |
(和) |
Wireless Communications / MIMO / Cooperative MIMO / CSI Feedback / Coordinated Multi-Point (CoMP) / / / |
(英) |
Wireless Communications / MIMO / Cooperative MIMO / CSI Feedback / Coordinated Multi-Point (CoMP) / / / |
文献情報 |
信学技報, vol. 113, no. 37, RCS2013-31, pp. 49-54, 2013年5月. |
資料番号 |
RCS2013-31 |
発行日 |
2013-05-09 (RCS) |
ISSN |
Print edition: ISSN 0913-5685 Online edition: ISSN 2432-6380 |
著作権に ついて |
技術研究報告に掲載された論文の著作権は電子情報通信学会に帰属します.(許諾番号:10GA0019/12GB0052/13GB0056/17GB0034/18GB0034) |
PDFダウンロード |
RCS2013-31 |
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