Full duplex device-to-device communication in cellular networks

Abstract

To address the problem of radio spectrum congestion due to increasing demand for wireless communications services, cellular communication systems are going towards small cells with small transmit powers. At the same time, in-band full-duplex (FD) radio design has gained considerable attention due to achievements in signal processing that can make design of full-duplex radios possible for systems with small transmit power. In theory full-duplex radios can double the spectral efficiency of the system. However existing radios still do not provide enough self-interference (SI) cancelation to be used in large transmit power systems. Meanwhile device-to-device communication (D2D) is seen as a promising idea to increase the performance of wireless networks. In D2D, users in vicinity communicate directly without going through base station. So far, very limited work has been carried out to study the applicability of available full-duplex radios in D2D. In this thesis, we investigate full-duplex D2D and amount of self-interference cancelation required in D2D in cellular systems. While D2D users share the same radio resources with cellular users, both cellular and D2D pair will receive interference. Resource allocation and interference management become crucial in D2D communication. Both uplink and downlink resource sharing are considered. In uplink resource sharing, to handle the interference on the base station power control is used in D2D transmitter. To deal with the interference at D2D receivers from cellular user's uplink transmission, interference-limited-area (ILA) method is used to select users with negligible interference on them. When D2D pair is using downlink resources of cellular users, users receive interference from D2D transmissions. Limiting this interference is also done using ILA method. On the other hand, for the purpose of resource sharing , the user with smallest downlink transmit power is selected to minimize the interference on D2D receivers. Half-duplex (HD) and full-duplex D2D scenarios are considered in both uplink and downlink resource sharing. Simulations show that how much of self-interference cancelation is required in different scenarios. Effects of the numbers of the selected users for resource sharing, distance between D2D users and also inter-cell interference is studied. It can be concluded that using available full-duplex radios in D2D communication can almost reach the theoretical doubling of throughput in full-duplex mode compared to half-duplex mode.

CORE: A Clustering Optimization Algorithm for Resource Efficiency in LTE-A Networks

“…As stated in Lemma 1, the gain achieved by clustering equals the aggregation of the individual gains. Therefore, Lemma 2 can be directly derived from (15).…”

“…In a first step of the algorithm, clusters in which CHs have H i = ∅ are created (lines [3][4][5][6][7][8][9][10][11][12][13][14]. Subsequently, in a second phase (lines [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29], conflicting situations between UEs that could be either simple CMs or CHs are resolved. Specifically, the most beneficial association in terms of resources' usage is investigated for these UEs.…”

LTE Advanced Networks- Secure Data Sharing Strategy for D2D Communication technique

“…However, most of them have focused on resource allocation and interference management or mode selection [6]- [10] while only very few efforts have been made on security issues [11]- [13]. Specifically, instead of interference mitigation and avoidance, the authors in [12] exploit interference against eavesdropping, which is an effective way to enhance information-theoretic secrecy capacity.…”

Active and Passive Self-Interference Cancellation Techniques for Full-Duplex Systems in the Next Generation (5G) of Mobile Communication Networks

“…D2D permits user equipment such as mobile phone or any devices to communicate with other devices in short distances on requiring that low power consumption without routing to traditional base station [BS]. The traffic routing in D2D communication should be offloaded from macro base station [21][22][23]. Based on predicted higher data rate that will be offered or applicable as a result of evolution sequences, we should introduce this newest type of communication.…”