In TD-SCDMA, due to single-stream beam-forming, there is a limit in peak data rate and the spatial multiplexing is not possible. In LTE-A or B3G, the requirements for the peak data rate and the cell throughput is very...In TD-SCDMA, due to single-stream beam-forming, there is a limit in peak data rate and the spatial multiplexing is not possible. In LTE-A or B3G, the requirements for the peak data rate and the cell throughput is very high, multi-streams beam-forming and spatial division multiple access (SDMA) are effective measures to meet these requirements. In this paper, enhancement of beam-forming technique is presented to support the multi-streams beam-forming and the SDMA.展开更多
Two reduced-complexity decoding algorithms for unitary space-time codes based on tree-structured constellation are presented. In this letter original unitary space-time constellation is divided into several groups. Ea...Two reduced-complexity decoding algorithms for unitary space-time codes based on tree-structured constellation are presented. In this letter original unitary space-time constellation is divided into several groups. Each one is treated as the leaf nodes set of a subtree. Choosing the unitary signals that represent each group as the roots of these subtrees generates a tree-structured constellation. The proposed tree search decoder decides to which sub tree the receive signal belongs by searching in the set of subtree roots. The final decision is made after a local search in the leaf nodes set of the se-lected sub tree. The adjacent subtree joint decoder performs joint search in the selected sub tree and its “surrounding” subtrees,which improves the Bit Error Rate (BER) performance of purely tree search method. The exhaustively search in the whole constellation is avoided in our proposed decoding al-gorithms,a lower complexity is obtained compared to that of Maximum Likelihood (ML) decoding. Simulation results have also been provided to demonstrate the feasibility of these new methods.展开更多
文摘In TD-SCDMA, due to single-stream beam-forming, there is a limit in peak data rate and the spatial multiplexing is not possible. In LTE-A or B3G, the requirements for the peak data rate and the cell throughput is very high, multi-streams beam-forming and spatial division multiple access (SDMA) are effective measures to meet these requirements. In this paper, enhancement of beam-forming technique is presented to support the multi-streams beam-forming and the SDMA.
基金Supported by the National Natural Science Foundation of China (No.60572148).
文摘Two reduced-complexity decoding algorithms for unitary space-time codes based on tree-structured constellation are presented. In this letter original unitary space-time constellation is divided into several groups. Each one is treated as the leaf nodes set of a subtree. Choosing the unitary signals that represent each group as the roots of these subtrees generates a tree-structured constellation. The proposed tree search decoder decides to which sub tree the receive signal belongs by searching in the set of subtree roots. The final decision is made after a local search in the leaf nodes set of the se-lected sub tree. The adjacent subtree joint decoder performs joint search in the selected sub tree and its “surrounding” subtrees,which improves the Bit Error Rate (BER) performance of purely tree search method. The exhaustively search in the whole constellation is avoided in our proposed decoding al-gorithms,a lower complexity is obtained compared to that of Maximum Likelihood (ML) decoding. Simulation results have also been provided to demonstrate the feasibility of these new methods.
