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Joint source and relay optimization for interference MIMO relay networks
Muhammad R A Khandaker1, Kai-Kit Wong1
1Department of Electronic and Electrical Engineering, University College London, Torrington Place, London, WC1E 7JE UK.
EURASIP Journal on Advances in Signal Processing
|April 1, 2020
Summary
This study minimizes maximal mean-square error in multi-cellular MIMO relay systems using amplify-and-forward. Proposed alternating optimization and SDP solutions offer effective performance under power constraints.
Area of Science:
- Wireless communication systems
- Signal processing
- Information theory
Background:
- Multi-cellular systems face interference challenges.
- Severe attenuation necessitates relay nodes for communication.
- Multiple-Input Multiple-Output (MIMO) enhances spectral efficiency.
Purpose of the Study:
- To minimize the maximal mean-square error (MSE) in multi-cellular MIMO relay systems.
- To optimize source, relay, and receiver matrices under power constraints.
- To develop efficient solutions for amplify-and-forward (AF) relaying.
Main Methods:
- Alternating optimization of system matrices.
- Development of a simplified semidefinite programming (SDP) solution.
- Error covariance matrix decomposition technique.
Main Results:
- Proposed alternating optimization effectively reduces MSE.
- The SDP-based approach provides a computationally efficient solution.
- Both one-way and two-way AF relaying mechanisms were analyzed.
Conclusions:
- The proposed methods are effective for mitigating MSE in complex relay networks.
- SDP offers a practical alternative to complex iterative optimization.
- The research contributes to robust MIMO relay communication design.
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