通信工程文献翻译——摘要

设备间(D2D)通信可以由蜂窝基础设施支撑来提高资源利用率、提高用户的吞吐量和节约电池能量。在这样的网络中,功率分配和模式选择是至关重要的问题。在非理想CSI下解决功率的联合优化和模式选择,我们提出一个最优的、能量感知的联合功率分配和模式选择(JPAMS)计划。首先,我们在满足不同服务质量(QoS)约束的同时，推导出D2D和手机连接功率最小化的封闭解。第二，基于派生功率分配，我们在非理想CSI中解决模式选择问题。此外,我们需要理论分析和仿真结果来评估D2D通信的方案。

关键词：功率分配 模式选择；D2D通信；非理想CSI；能量感知

1.引言

我们强烈期望由蜂窝基础设施支持的设备到设备（D2D）通信来提高能量效率和网络吞吐量[1]。功率分配和模式选择对D2D通信有很多关注[2–8]。在文献[2]中，作者提出了限制蜂窝链路的SINR变小的功率控制方案。一个功率分配的启发式贪心算法在文献[2]中被提出。在[3]中开发了用于功率分配的启发式贪婪算法。在文献[4]中，提出了模式选择算法以在满足蜂窝用户的SINR约束的同时实现最大速率。文献[5]的作者得出一个军事算法,其目的是在最大化整体能力的同时选择最优传输方式。在文献[6]中，作者设计一个D2D和蜂窝链路的传输模式选择和功率分配启发式算法。在文献[7]和[8]中，在具有一个D2D链路和一个蜂窝链路的单个小区中研究联合功率分配和模式选择。

然而,所有上述文献假设在基站（BS）和D2D终端两者处的理想CSI。由于信道波动,有限反馈,信道估计和量化误差,理想的CSI不可能得到[9]。因此我们很难在非理想CSI的实际信道中应用结果。

为了在非理想的CSI中解决功率的联合优化和模式选择，我们得到一个D2D通信的最优、能量感知的联合功率分配和模式选择(JPAMS)方案。这个方案先获得优化问题的封闭解,其目标是最小化发送功率,同时满足D2D和蜂窝链路的不同服务质量(QoS)约束。基于解决方案的封闭特性,我们在非理想CSI中开发一个模式选择策略。

本文的其余部分组织如下。在第二部分介绍了系统和信道模型，在第三部分介绍了功率分配的联合优化和模式选择方案，在文章的第四章和第五章分别给出了仿真结果和结论部分。定理的推导在附录中给出。

2.系统模型

2.1场景描述

我们考虑由一个蜂窝用户（CUE）C和多个D2D对......

Abstract: Device-to-device (D2D) communications can be underlaid with a cellular infrastructure to increase resource utilization, improve user throughput and save battery energy. In such networks, power allocation and mode selection are crucial problems. To address the joint optimization of power and mode selection under imperfect CSI, we propose an optimal, energy-aware joint power llocation and mode selection (JPAMS) scheme. 

First, we derive the closed-form solution for the power minimization for both D2D and cellular links while satisfying different quality of service (QoS) constraints. Second, we address the mode selection problem in presence of imperfect CSI, based on the derived power allocation. Moreover, the theoretical analysis and simulation results are presented to evaluate the proposed scheme for the D2D communications.

Keywords: power allocation; mode selection; D2D communications; imperfect CSI; energy-aware

I. INTRODUCTION

Device-to-device (D2D) communications supported by a cellular infrastructure are strongly expected to improve energy efficiency and network throughput[1]. Power allocation and mode selection have attached much attentions for D2D communications[2–8]. In[2], the authors propose a power control scheme that constrains the signal to interference plus noise ratio (SINR) degradation of the cellular link. A heuristic greedy algorithm for power allocation is developed in [3]. In[4], a mode selection algorithm is proposed to achieve the maximum sum-rate while satisfying the signal-to-interference plus noise ratio (SINR) constraints of the cellular users. The authors in[5] derive a distance-dependent algorithm, which aims at selecting the optimal transmission mode while aximizing the overall capacity. In[6], the authors design a heuristic algorithm for transmission mode selection and power allocation for both D2D and cellular links. In[7] and[8], the joint power allocation......