With this aim, this paper addresses the use of short-range device-to-device (D2D) communications as enabling technology to efficiently manage the radio spectrum and to reduce the energy consumption of MTC devices. Therefore, novel solutions are needed to efficiently exploit the radio resources for MTC, considering, among others, the need to optimize transmissions for small data packets. The main reason for this new trend is the fact that 5G wireless systems will need to enable the coexistence between MTC and human-type communications (HTC). This could maximize the sum throughput and hence, guarantees the reliability of both the D2D and cellular connections.Ĭurrent and future releases of 3GPP standards will include enhancements in LTE-Advanced for machine-type communications (MTC). Based on the subjective and objective analysis of the work available to date, it is also envisaged that adopting a multi–antenna beamforming mechanism with power control such that the transmit power is maximized towards the direction of the intended D2D receiver node and limited in all other directions will minimize the interference in the network.

This work presents a comprehensive review of the existing interference mitigation schemes present in the open literature.

Efficient interference mitigation schemes are a principal requirement in order to optimize the system performance. D2D transmission radiates in all directions, generating undesirable interference to primary cellular users and other D2D users sharing the same radio resources resulting in severe performance degradation. Containment of the interference among D2D nodes and cellular users is one of the major problems. However, integration of D2D communication in cellular systems at the same time introduces new technical challenges that need to be addressed. It results in several transmission gains, such as improved throughput, energy gain, hop gain, reuse gain, etc. D2D provides the opportunity for users located in close proximity of each other to communicate directly, without traversing data traffic through the eNB. To respond to this challenge, Device–to–Device (D2D) communication in cellular networks is viewed as a promising solution, which is expected to operate, either within the coverage area of the existing eNB and under the same cellular spectrum (in-band) or separate spectrum (outband). It is driving the telecommunication industry as well as the research community to come up with new paradigms that will support such high data rate requirements within the existing wireless access network, in an efficient and effective manner. The mobile data traffic has risen exponentially in recent days due to the emergence of data intensive applications such as online gaming, video sharing etc. Simulation results show that the proposed algorithm can effectively improve the system performance.

Finally, we use the Kuhn–Munkres (KM) algorithm to achieve the optimal matching between D2D clusters and cellular channel to maximize the total capacity of D2D users. Then, D2D users in the same cluster are modeled as a non-cooperative game, the expressions of D2D users’ transmission power and energy harvesting time are derived by using the Karush–Kuhn–Tucker (KKT) condition, and the optimal transmission power and energy harvesting time are allocated to D2D users by the joint iteration optimization method. This algorithm firstly uses a heuristic dynamic clustering method to cluster D2D users and those in the same cluster can share the same channel. This paper assumes that multiple device-to-device (D2D) users can reuse the same uplink channel and base station (BS) supplies power to D2D transmitters by means of wireless energy transmission the optimization problem aims at maximizing the total capacity of D2D users, and proposes a power control and channel allocation algorithm for the energy harvesting D2D communications underlaying the cellular network.

Bandwidth in communication