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A broadcasting network with heterogeneous users, where the single-antenna (weak) users cooperate in groups to receive the high-rate data broadcasted from the base station.
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... this paper, we propose to improve the QoS of multiple single-antenna users in a MIMO broadcasting network through various user cooperation strategies. The considered network is shown in Fig. 1, where there is one multiantenna BS broadcasting the multimedia service and several multiantenna (strong) users and single-antenna (weak) users receiving the service. The considered network presents two distinct features. First, it reflects a real network comprised of heterogeneous users equipped possibly with different numbers of ...
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... shown previously in Fig. 1, the considered broadcasting network is comprised of a multiantenna BS and several multiantenna and single-antenna users ("heterogeneous users"). While the multiantenna users can exploit a wealth of existing SM techniques to achieve reliable high-rate communication, the lack of sufficient number of antennas presents a challenge to ...
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... scheme and then the DF scheme. Note that the CSI acquisition and cooperation overhead are not accounted for in this comparison. In fact, the AF scheme has the largest CSI acquisition and cooperation overhead while the DF scheme has the minimum. This suggests that there exists a tradeoff between the cooperation overhead and the system performance. Fig. 10 compares the SER performance of AF cooperation schemes by taking into account the channel estimation errors. In the simulation, for N P = 4, the pilot matrix P is chosen as a 4 × 4 DFT matrix, which is an orthogonal matrix with a constant ...
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... N P = 8 and N P = 16, the 4 × 4 DFT matrix is concatenated two and four times, respectively, to form the pilot matrix. As seen in can significantly improve the performance (e.g., N P = 4 with one iteration outperforms N P = 16 with no iteration). Fig. 11 shows the mean squared error (MSE) of the proposed channel estimation. It is seen that the proposed iterative mechanism significantly reduces the MSE and converges after only 2-3 iterations. This verifies that the proposed iterative algorithm can provide accurate overall channel estimates for AF cooperation systems with the aid of very ...
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Citations
according to Internet of vehicles alliance division strategy, aiming at Cooperative communication [1] among Road Side Unit (RSU)[2]in the one-way road environment cannot explore the ability to share information of moving vehicle in opposite direction, which reduces the limitation of cooperative communication data transmission capacity. This paper proposes a kind of shared relay vehicle selection strategy to realize the cooperative information transmission among road side units on the one-way road, this strategy though the vehicle to the rear to share information and use geometric coverage theory to select shared relay vehicle, which can effectively reduce the number of repeat forward shared information and data redundancy in the network and improve the capabilities to share information of road side unit. Through a large number of experiments verify the rationality and effectiveness of the strategy.
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