Abstract
In this paper, we present a low-complexity method to generate a transmit beamforming vector for multiple-input-multiple-output (MIMO) systems. We begin by introducing new definitions regarding orthogonality between two complexvalued vectors and then present new expressions of complex rotation matrices for the complex vector orthogonalization. The rotation matrices are utilized to derive the weight vector for the maximum-norm combining (MNC) process of two complex vectors, which provides a constructive basis for a new beamforming method. The proposed transmit beamforming method uses successive column combining of MIMO channel matrices based on MNC, and as a result, an approximate solution to the optimum beamforming vector is obtained. The proposed method offers a good tradeoff between complexity and performance. Simulation results demonstrate that the proposed beamforming method achieves the near-optimal performance with much reduced computational complexity, compared to the optimal beamforming scheme using singular-value decomposition (SVD) of the channel matrix.
| Original language | English |
|---|---|
| Article number | 4907470 |
| Pages (from-to) | 2067-2075 |
| Number of pages | 9 |
| Journal | IEEE Transactions on Wireless Communications |
| Volume | 8 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - 2009 Apr |
Bibliographical note
Funding Information:This paper was presented in part at the IEEE International Conference on Communications, Glasgow, Scotland, June 2007. This research was supported by the Ministry of Knowledge Economy, Korea, under the Information Technology Research Center support program supervised by the Institute for Information Technology Advancement (IITA-2008-C1090-0801-0013).
Keywords
- Complex rotation matrix
- Maximum-norm combining (MNC)
- Multiple-input-multiple-output (MIMO) systems
- Transmit-beamforming technique
ASJC Scopus subject areas
- Computer Science Applications
- Electrical and Electronic Engineering
- Applied Mathematics