Distributed Space-Time Interference Alignment with Moderately-Delayed CSIT
SCOPUS
- Title
- Distributed Space-Time Interference Alignment with Moderately-Delayed CSIT
- Authors
- LEE, NAMYOON; Tandon, Ravi; Heath, RW
- Date Issued
- 2015-02
- Publisher
- IEEE
- Abstract
- This paper proposes an interference alignment method with distributed and delayed channel state information at the transmitter (CSIT) for a class of interference networks. The core idea of the proposed method is to align interference signals over time at the unintended receivers in a distributed manner. With the proposed method, achievable tradeoffs between the sum of degrees of freedom (sum-DoF) and feedback delay of CSI are characterized in both the X-channel and three-user interference channel to reveal the impact on how the CSI feedback delay affects the sum-DoF of the interference networks. A major implication of derived results is that distributed and moderately delayed CSIT is useful to strictly improve the sum-DoF over the case of no CSI at the transmitter in a certain class of interference networks. For a class of X-channels, the results show how to optimally use distributed and moderately delayed CSIT to yield the same sum-DoF as instantaneous and global CSIT. Furthermore, leveraging the proposed transmission method and the known outer bound results, the sum-capacity of the two-user X-channel with a particular set of channel coefficients is characterized within a constant number of bits.
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/37763
- DOI
- 10.1109/TWC.2014.2363475
- ISSN
- 1536-1276
- Article Type
- Article
- Citation
- IEEE Transactions on Wireless Communications, vol. 14, no. 2, page. 1048 - 1059, 2015-02
- Files in This Item:
- There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.