On the Throughput of MIMO-Empowered Multi-hop Cognitive Radio Networks
Abstract
Cognitive radio (CR) and multiple-input multiple-output (MIMO) are two independent physical layer technologies that have made significant impact on wireless networking. CR operates on the channel/band level to exploit white space across spectrum dimension while MIMO operates within the same channel to improve spectral efficiency within the same band. In this paper, we explore MIMO-empowered CR network, which we call CRN(MIMO), to achieve the ultimate flexibility and efficiency in dynamic spectrum access and spectrum utilization. Given that CR and MIMO handle interference at different levels (across channels vs. within a channel), we are interested in how to jointly optimize both so as to maximize user throughput in a multi-hop network. To answer this question, we develop a tractable mathematical model for CRN(MIMO), which captures the essence of channel assignment (for CR) and degree-of-freedom (DoF) allocation (for MIMO) within a channel. Based on this mathematical model, we use numerical results to show how channel assignment in CRN and DoF allocation in MIMO can be jointly optimized to maximize throughput. More important, for a CRNMIMO with AMIMO antennas at each node, we show that joint optimization of CR and MIMO offers more than AMIMO-fold throughput increase than a CRN (without MIMO).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2010
- Accession Number
- ADA536109
Entities
People
- Cunhao Gao
- Sastry Kompella
- Yantian Hou
- Yi Shi
Organizations
- United States Naval Research Laboratory