Conference Paper

Cross-Layer Interference Mitigation for Cognitive Radio MIMO Systems

Joint Res. Inst. for Signal & Image Process., Heriot-Watt Univ., Edinburgh, UK
DOI: 10.1109/icc.2011.5962698 Conference: Communications (ICC), 2011 IEEE International Conference on
Source: DBLP


In this paper, we investigate the interference mitigation from a cross-layer perspective for a cognitive radio (CR) multiple-input multiple-output (MIMO) network coexisting with a primary time-division-duplexing (TDD) system. The channel allocation in the media access control (MAC) layer and a subspace-based precoding scheme in the physical layer of the CR network are jointly considered to minimise the interference to the primary user and maximise the CR throughput. Two distributed cross-layer algorithms, namely, joint iterative channel allocation and precoding (JICAP) and non-iterative channel allocation and precoding (NICAP), are proposed for the cases with and without channel information among CR nodes, respectively. Moreover, a channel estimation scheme is also proposed to enable the NICAP. The effectiveness of the proposed algorithms over non-cross-layer counterpart is demonstrated via simulations.

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Available from: Cheng-Xiang Wang, Oct 02, 2015
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