| On current trends, Device-to-Device (D2D) communication underlaying the cellular networks has been included into standard process of IMT-Advanced system. As a significant proximity communication technology, D2D communication is able to provide a more convenient and flexible network access, and can effectively improve the network capacity and resource utilization. In the meanwhile, D2D communication is able to meet mobile and broadband multimedia application.In the hybrid networks, the pair of D2D users are often close to each other, and has high link quality. Therefore, the characteristics of D2D communication include shorter time delay, lower power consumption, and higher data transmission rate. However, D2D communication underlaying cellular network can cause serious interference between cellular users and D2D users by sharing spectrum resource. To solve the interference problem between cellular users and D2D users, there have been many D2D interference coordination researches, and some of them have got some achievements of improving the performance of D2D system. However, there are still some problems that have not been solved. In this dissertation, we investigate the interference coordination schemes for three scenarios, including D2D unicast, D2D multicast in the hybrid network and a heterogeneous D2D network underlaying cellular network respectively. The main contribution of this dissertation can be summarized as follows:1) To solve the interference problem between cellular users and D2D users for D2D unicast in the hybrid network, we proposed an interference coordination scheme which D2D communication reuses uplink resource of cellular network under the base station assisted network. Firstly, by setting the threshold of the D2D receiver’s SINR, and then determined the transmission mode for the D2D users. Secondly, according to the Hungarian algorithm and the proposed suboptimization algorithm, we allocated the cellular users’spectrum for the D2D users in a period of response time. Finally, the dynamic power control algorithm based on the use location is proposed and D2D transmission power can be set. We concreted realization of the process and the theoretical derivation of the three algorithms, the simulation results showed that the proposed algorithm can reach the same level with the optimal algorithm for the uplink cellular users, and reaction time and the complexity can be reduced.2) To solve the interference problem between cellular users and D2D multicast users in the hybrid network, we proposed an interference coordination scheme for the D2D multicast communication underlaying the cellular network. To increase the overall capacity and improve resource utilization, a novel interference coordination scheme is proposed. The proposed scheme includes three steps. Firstly, a multicast concept for D2D communication underlaying a cellular infrastructure was investigated, and the process of D2D multicast had been established.in order to mitigate the interference from D2D multicast transmission to cellular networks, a dynamic power control scheme is proposed that can determine the upper bound of D2D transmitter power based on the location of Base Station and areas of adjacent cells from the coverage area of D2D multicast group. Secondly, an interference limited area control scheme that reduces the interference from cellular network to each D2D multicast receiver is proposed. The proposed scheme does not allow cellular users located in the interference limited area to reuse the same resources as the D2D multicast group. Finally, two resource block allocation rules are proposed to select the appropriate resource block s from a candidate resource block set for D2D multicast group. From the simulation results, it is confirmed that the proposed schemes improve the performance of the hybrid system compared to the conventional ways. 3) To solve the interference problem among cellular users, Femto users and D2D users for heterogeneous D2D network, we proposed an interference coordination scheme which cellular base station and the HeNB (Home NodeB) had joint control for D2D communication. Firstly, based on the characteristics of D2D communication and the increasing need of indoor multi-media business, we studied the cases of D2D sharing the uplink resource under cellular network and femtocell reusing the spectrum resource. Secondly, we analyzed the D2D interference model of heterogeneous D2D network, and determined the process of selection and establishment of D2D communication under the joint control of cellular base station and HeNB for the heterogenedus D2D network. Finally, through the optimization of capacity and energy, and minimizing interference, we proposed three kinds of interference coordination schemes. On the premise of guaranteeing the cellular and Femtocell network qualities, the simulation results show that the capacity of heterogeneous D2D network can be improved by using proposed schemes. |
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