A Two-Way Cooperative D2D Communication Framework for a Heterogeneous Cellular Network

Abstract

This paper analyzes the performance of two-way OFDMA based cooperative device-to-device communication (C-D2D) framework in a heterogeneous cellular network. In the proposed work, a heterogeneous network (HetNet) is considered where the base station (BS) of the macro cell is interested in communicating with the BS of smaller cells such as micro, pico or femto cell, nested inside the macro cell. Each macro cell also consists of the number of cellular users which when given an opportunity, would like to communicate directly via D2D link. The cellular users which communicate through D2D link is defined as D2D users. Due to infrastructure failure, if no direct communication link is available between two BSs then HetNet adopts a time-slotted two-phase C-D2D protocol. Macro cell BS selects a D2D user as an amplify-and-forward (AF) two-way relay to facilitate communication between two BSs. In Phase I, both the BSs send their data over N subcarriers to the D2D transmitter (DT). Subsequently, in Phase II, DT amplifies the received signal and forward it to the BSs over D subcarriers. The remaining $$N-D$$ subcarriers are used by DT for D2D communication. Results show that the proposed analysis facilitates D2D communication in HetNet, and also improves the quality-of-service (QoS) of the BSs as compared to conventional AF protocol.