标题： 分布式线性预编码优化和基站选择用于上行异构网络 显示英文标题

标题： Distributed Linear Precoder Optimization and Base Station Selection for an Uplink Heterogeneous Network

摘要： 在一个异构无线蜂窝网络中，每个用户可能会被多个接入点（如宏基站/微基站/中继基站/毫微微基站）覆盖。 在这种网络中最大化总效用（如系统吞吐量）的有效方法是联合优化用户的线性预编码器以及它们与基站的关联。 本文首先证明了这个联合优化问题是一个NP难问题，因此难以全局最优求解。 为了找到局部最优解，我们将该问题建模为一个非合作博弈，在其中用户和基站都作为参与者。 我们为参与者引入了一组新的效用函数，并证明了由此产生的博弈的每一个纳什均衡都是原始总效用最大化问题的平稳解。 此外，我们开发了一种基于最佳响应类型的算法，使参与者能够分布式地达到博弈的纳什均衡。 仿真结果表明，所提出的分布式算法可以有效缓解局部基站拥塞，并同时实现在异构网络中的高吞吐量和负载均衡。 显示英文摘要

摘要： In a heterogeneous wireless cellular network, each user may be covered by multiple access points such as macro/pico/relay/femto base stations (BS). An effective approach to maximize the sum utility (e.g., system throughput) in such a network is to jointly optimize users' linear procoders as well as their base station associations. In this paper we first show that this joint optimization problem is NP-hard and thus is difficult to solve to global optimality. To find a locally optimal solution, we formulate the problem as a noncooperative game in which the users and the BSs both act as players. We introduce a set of new utility functions for the players and show that every Nash equilibrium (NE) of the resulting game is a stationary solution of the original sum utility maximization problem. Moreover, we develop a best-response type algorithm that allows the players to distributedly reach a NE of the game. Simulation results show that the proposed distributed algorithm can effectively relieve local BS congestion and simultaneously achieve high throughput and load balancing in a heterogeneous network.