A practical multiuser cooperative transmission scheme denoted as
Virtual Maximum Ratio Transmission
(VMRT) for multiple-input multiple-output-orthogonal frequency division multiple access ...(MIMO-OFDMA) relay-based networks is proposed and evaluated in the presence of a realistic channel estimation algorithm and using low-density parity-check (LDPC) codes. It is shown that this scheme is robust against channel estimation errors. It offers diversity and array gain, keeping the complexity low with a multiuser and multiantenna channel estimation algorithm that is simple and efficient. In addition, the combination with LDPC codes provides improved gains; diversity gains larger than 6 dB can be easily obtained with a reduced number of relays. Thus, this scheme can be used to extend coverage or increase system throughput by using simple cooperative OFDMA-based relays.
Uplink Channel Estimation for Multi-user OFDM-based Systems Ribeiro, Carlos; Fernández-Getino Garcia, M. Julia; Gil Jiménez, Víctor P. ...
Wireless personal communications,
10/2008, Letnik:
47, Številka:
1
Journal Article, Conference Proceeding
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Virtual Maximum Ratio Transmission
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