Ad hoc网络非合作博弈功率控制研究

根据Ad hoc网络的分布式特性,提出一种新的以干扰为代价的非合作功率控制博弈算法,让产生较大干扰的发送节点受到更多惩罚,验证其存在唯一的纳什均衡。仿真结果表明,该算法具有较快的收敛速度,与NPG和NPGP模型相比,可以有效抑制产生较大干扰的链路的发送功率。在保证链路接收信号质量的同时,不仅有效减小干扰以提高网络容量,而且还在一定程度上兼顾了节点之间的公平性。     

干扰系统中基于非合作博弈的功率控制

对现有干扰系统中非合作博弈功率控制问题进行了总结和分析。主要分析了四种效用函数,并研究了相应的应用策略。从中可以看出,基于互信息量的效用函数运算较复杂,目标容量确定下的效用函数与目标信干噪比确定下的效用函数在性能不影响的情况下,计算复杂度大大降低。基于效率的效用函数能有效抑制各用户对发射功率的盲目追求,提高了用户单位功率下的性能,即提高了效率。     

一种新的认知无线电非合作功率控制博弈算法

当认知无线电网络以"衬底式"(Underlay)的方式与主用户网络共享频谱时,需要对认知用户进行功率控制,以确保认知用户在不干扰主用户的前提下,公平地共享认知频谱资源。利用博弈分析的方法,设计了一个基于链路增益因子的代价函数,并据此提出了一种新的非合作功率控制博弈算法。仿真结果表明,该算法的均衡结果既改善了用户的帕累托(Pareto)性能,又提高了链路增益较差的用户的吞吐量,实现了网络资源的平等共享。     

基于非合作博弈的联合功率与速率控制算法

在多媒体CDMA网络中,需要对用户的功率进行控制,既保证每个用户的QoS要求,又不增加对其它用户的干扰,同时还要对用户的数据速率进行控制,以避免拥塞。将功率和速率控制等效为一个具有N个用户的非合作博弈,用效用函数表征用户对系统服务质量的满意程度,用代价函数描述达到通信要求所消耗的无线资源,从而将联合功率与速率控制算法描述为最大化净效用函数（效用函数和代价函数之差）的过程,最终得到系统中各用户全局最佳数据传输速率和达到服务质量所需的最小发射功率组合,并证明了纳什均衡的存在性。     

基于非合作博弈的5G异构网络功率分配机制

随着移动通信业务从4G向5G的过渡升级,现阶段移动通信网络呈现多个网络共存和相互融合的局面,5G异构网络需要解决不同业务需求和技术体制下的频谱资源的高效分配问题。首先,介绍5G异构网络资源管理的现状及其问题。然后,针对分级5G异构网络架构,提出一种基于非合作博弈模型的功率分配算法,通过建立非合作博弈模型对算法进行论证分析,证明该算法存在唯一的纳什均衡解。最后,通过仿真实验初步验证提出的功率分配算法的可行性和有效性。     

基于感知无线电非合作博弈功率控制算法的研究

本文基于Goodman提出的非合作博弈功率控制模型改进了代价函数。针对感知无线电系统（CR）中各用户的通信需求,采用多载波码分多址（MC-CDMA）感知无线电系统,解决感知用户对主用户干扰和通信中断等问题,为实现感知频谱资源的有效分配,提出了一种新的感知无线电系统功率控制博弈算法。通过仿真表明,该算法同几种经典算法相比,既满足不同种类用户SIR要求,又提高了系统吞吐量,实现了对不同用户发射功率的有效控制,且系统性能明显提高。     

基于认知无线电系统的新型合作功率控制博弈算法

以改进的空时分集OFDM-CDMA系统为基础，研究已认知频谱资源的公平分配问题，根据信道状况，吞吐量最大化和功率限制需求，提出了一种合作功率控制纳什议价博弈算法，以有效地降低认知用户（secondary users）的发射功率，提高网络吞吐量。仿真结果表明该算法满足了认知用户公平共享频谱资源的需求，在相同功率消耗情况下，网络吞吐量显著提高。     

多无人机任务集结合作博弈优化自组织协同控制

基于一致性理论的多无人机系统自组织协同作战是未来无人机应对突发任务的重要方式,任务集结是协同作战的首要行动和自组织协同控制的重要内容。为优化集结行动中系统任务状态协调过程能量最优性、协同控制动态响应性和集结行动时效性3个性能指标,采用基于快速一致性控制算法的协同控制结构,在合作博弈框架下给出多无人机系统自组织协同与优化控制问题描述,建立了优化控制输入的Pareto解集,采用Nash讨价还价方法给出基本合作博弈优化一致性控制算法。在基本算法中引入过去状态差值,并以优化目标构建适应度函数,采用遗传算法优化代价函数的加权矩阵,得到改进合作博弈优化一致性控制算法。理论分析和仿真实验验证了方法的可行性和有效性。     

无线数据网络中的非合作功率控制

为了更好地解决CDMA无线数据网络中的远近公平问题,在一种无线数据网络的基础效用函数的基础上,对用户的链路增益与发射功率作定价,提出了一种新的效用函数,并证明了这种非合作功率控制博弈中存在唯一的纳什均衡。仿真结果表明系统的远近公平问题得到了很好的改善。     

基于合作博弈的多无人机任务研究

针对多无人机合作博弈问题,对多无人机任务策略进行研究。通过考虑合作联盟的目标价值指标函数和代价指标函数,建立多无人机合作联盟博弈模型,给出一种合作博弈的求解方法,最终得到多无人机最优联盟策略。仿真结果表明,该方法具有很好的可行性和有效性。     

Non-cooperative power control game for adaptive modulation and coding

Adaptive modulation and coding (AMC) provides the flexibility to match modulation and coding scheme (MCS) to signal to interference plus noise ratio (SINR) of users. To reduce the transmission power and maintain the transmission quality, power control is normally combined with AMC. While the target SINR of power control is fixed, therefore non-cooperative power control game for AMC (NPGA) algorithm was proposed to adapt to the dynamic target SINR changes according to MCS. In NPGA, we formulate system transmission efficiency via utility, where the utility function is constructed based on the modulation and coding efficiency with non-cooperative game theory. It is demonstrated theoretically that NPGA can satisfy the conditions of the supermodular games, and its solution is optimal. The simulation results show that NPGA can improve system transmission efficiency and signal quality with low transmission power, and the convergence performance of NPGA is more fast-effectiveness compared with geometric programming algorithms.     

无线数据网络中基于斯塔克尔博格博弈的功率控制

功率控制是无线数据网络中资源管理的关键技术。为使无线数据网络中非合作博弈功率控制算法得到帕累托改进,将斯塔克尔博格博弈引入到无线数据网络功率控制算法中,使所有系统终端都工作在最佳的等信干比下,提出一个基于斯塔克尔博格博弈的分布式功率控制算法,并进行了数值仿真。仿真结果表明,该算法明显提高了系统的性能,使系统终端具有相对较高的效用和较低的发射功率,并使得无线网络资源的使用更加合理和公平,同时算法拥有较好的收敛性。     

A noncooperative power control game for multirate CDMA data networks

The authors consider a multirate code-division multiple acess system, in which all users have the same chip rate and vary their data rate by adjusting the processing gain. The receivers are assumed to be implemented using conventional matched filters, whose performance is sensitive to the received power levels. The authors' goal is to maximize the total system throughput by means of power control. A game theoretic approach is adopted. It is shown that for a certain type of pricing function, a unique Nash equilibrium solution exists and it possesses nice global properties. For example, it can be shown that for the optimal solution a high-rate connection should maintain a higher energy per bit than low-rate ones. The asymptotic spectral efficiency is also derived.     

Non-cooperative uplink power control in cellular radio systems

This paper presents uplink power control in cellular radio systems from an economic point of view. A utility function is defined for each mobile user, which reflects the user's preference regarding the carrier-to-interference ratio (CIR) and the transmitter power. We observe that, on one hand, mobile users prefer to transmit at a lower power for a fixed CIR. On the other hand, for a given transmitter power, users prefer to obtain a better CIR. Based on this observation, we make two fundamental assumptions about the utility function. We formulate the uplink power control problem as a non-cooperative N-person game. Under the two assumptions that we make about the utility function, there exists a Nash equilibrium. To show the generality of the framework, we study one special case by defining the utility as a linear function. This model encompasses many of the widely studied power control problems. A more general case is also studied by defining utility as an exponential function. This paper establishes a general economic-based framework for studying resource management in wireless networks and points out new research directions. This revised version was published online in July 2006 with corrections to the Cover Date.     

Non-cooperative uplink power control in cellular radio systems

This paper presents uplink power control in cellular radio systems from an economic point of view. A utility function is defined for each mobile user, which reflects the user's preference regarding the carrier-to-interference ratio (CIR) and the transmitter power. We observe that, on one hand, mobile users prefer to transmit at a lower power for a fixed CIR. On the other hand, for a given transmitter power, users prefer to obtain a better CIR. Based on this observation, we make two fundamental assumptions about the utility function. We formulate the uplink power control problem as a non-cooperative N-person game. Under the two assumptions that we make about the utility function, there exists a Nash equilibrium. To show the generality of the framework, we study one special case by defining the utility as a linear function. This model encompasses many of the widely studied power control problems. A more general case is also studied by defining utility as an exponential function. This paper establishes a general economic-based framework for studying resource management in wireless networks and points out new research directions.     

认知无线网络中基于Stackelberg博弈的功率控制新算法

针对认知无线网络中存在的干扰问题和功率消耗过大问题,提出了一种新的基于斯坦克尔伯格(Stackelberg)博弈的功率控制算法。建立了主次用户双层网络模型,将主用户设置为领导者,次用户设置为追随者,并对次用户产生的总干扰进行定量分析。在次用户多次博弈的过程中,动态地调整主用户单位干扰价格,在保证主用户自身正常通信前提下,尽量使得收益最大化,提高主用户的参与积极性。仿真实验表明,该算法在保证主次用户的服务质量（QoS）前提下,有效地减小了次用户的发射功率,而且能获得更高的系统容量。     

A nash game algorithm for SIR-based power control in 3G wireless CDMA networks

We propose a new algorithm for distributed power control in cellular communication systems. We define a cost for each mobile that consists of a weighted sum of power and square of signal-to-interference ratio (SIR) error and obtain the static Nash equilibrium for the resulting costs. The algorithm requires only interference power measurements and/or SIR measurements from the base station and converges even in cases where limits on available power render the target SIRs unattainable. Examples generated using realistic data demonstrate that, in demanding environments, the Nash equilibrium power provides substantial power savings as compared to the power balancing algorithm while reducing the achieved SIR only slightly. Additional simulations show that the benefit of the Nash equilibrium power control over the power balancing solution increases as the receiver noise power or number of users in the cell increases. The algorithm has the advantage that it can be implemented distributively. An additional benefit of the algorithm is that, based on their chosen cost function, mobiles may choose to "opt out", i.e., stop transmitting, if they determine that the power required to achieve their SIR objectives is more expensive to them than not transmitting at all.     

Joint random access and power control game in ad hoc networks with noncooperative users

We consider a distributed joint random access and power control scheme for interference management in wireless ad hoc networks. To derive decentralized solutions that do not require any cooperation among the users, we formulate this problem as noncooperative joint random access and power control game, in which each user minimizes its average transmission cost with a given rate constraint. Using supermodular game theory, the existence and uniqueness of Nash equilibrium are established. Furthermore, we present an asynchronous distributed algorithm to compute the solution of the game based on myopic best response updates, which converges to Nash equilibrium globally. Finally, a link admission algorithm is carried out to guarantee the reliability of the active users. Performance evaluations via simulations show that the game-theoretical based cross-layer design achieves high performance in terms of energy consumption and network stability.     

A power control game based on outage probabilities for multicell wireless data networks

We present a game-theoretic treatment of distributed power control in CDMA wireless systems using outage probabilities. We first prove that the noncooperative power control game considered admits a unique Nash equilibrium (NE) for uniformly strictly convex pricing functions and under some technical assumptions on the SIR threshold levels. We then analyze global convergence of continuous-time as well as discrete-time synchronous and asynchronous iterative power update algorithms to the unique NE of the game. Furthermore, we show that a stochastic version of the discrete-time update scheme, which models the uncertainty due to quantization and estimation errors, converges almost surely to the unique NE point. We finally investigate and demonstrate the convergence and robustness properties of these update schemes through simulation studies.