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Joint Source and Relay Optimization for Parallel MIMO Relays Using MMSE-DFE Receiver. Apriana Toding , Muhammad R. A. Khandaker and Yue Rong. Department of Electrical & Computer Engineering. Outline. MIMO Relay Communication System Model Proposed Approach Numerical Results Conclusions.
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Joint Source and Relay Optimization for Parallel MIMO Relays Using MMSE-DFE Receiver AprianaToding, Muhammad R. A. Khandaker and YueRong Department of Electrical & Computer Engineering
Outline • MIMO Relay Communication • System Model • Proposed Approach • Numerical Results • Conclusions
Introduction MIMO Relay Wireless Communication Figure 1. MIMO relay channel
Introduction • The MIMO relay network system can increase: • Efficiency • Reliability • Capacity • Coverage • Diversity • Main issue in MIMO relay wireless communication system is how to build the communication link when there are some obstacles between the transmitter and the receiver. • How to solve the issue: Provide more relay nodes between the transmitter and the receiver.
System Model Figure 2. Parallel MIMO relay channel
System Model Figure 3. Blok diagram of parallel MIMO relay channel stream 1 W1 Decode stream 1 stream 2 Subtract stream 1 Decode stream 2 W2 stream 3 yNd Decode stream 3 Subtract stream 1,2 W3 . . . . . . . . . stream Nd Subtract stream 1,2,… Nd-1 W Nd Decode stream Nd Figure 4. Blok diagram of the non-linear receiver
Proposed Approach • The received signal vector at the destination is • By introducing
Proposed Approach • By introducing the following QR decomposition • The MSE matrix is
The power constraints are • The optimal problem can be written as s.t. • The solution to the problem are given by
Simulation Environment • General parameter for all cases: • Constellation : BPSK • Transmit 1000 randomly generated bits in each channel realizations • Averaged through 200 channel realizations • Study cases • Case I:3 Relay nodes • Case II: 2,3 and 5 Relay nodes • Compare with existing algorithm of • NAF • MMSE Algorithm [9]
Results • Case I:BER versus SNRs with K=3
Results • Case II: BER versus SNRs with varying K
Summary We have- - demonstrated the advantages of using parallel relay diversity in MIMO relay communication system. - used a nonlinear MMSE-DFE receiver is used at the destination node. - have derived the optimal structure of the source precoding matrix and the relay amplifying matrices.
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