MESFET倍器的最佳设计

本文提出一种适用于优化倍频器终端，具有最大输出功率和变换增益的设计准则，这种设计技术，首先是在线性Ｓ参数基础上，推导出ＭＥＳＦＥＴ终端的计算。尽管相当简单，但这种近似法导出了期望的结果，使用该方法，获得了曾经报导过的最大输出功率变换增益的折裹法，实验与模拟结果相当吻合。     

MESFET倍频器的最佳设计

本文提出一种适用于优化倍频器终端，具有最大输出功率（Ｐ＿ｏｕｔ）和变换增益（Ｇ＿ｃ）的设计准则。这种设计技术，首先是在线性Ｓ参数基础上，推导出ＭＥＳＦＥＴ终端的计算。尽管相当简单，但这种近似法导出了期望的结果。使用该方法，获得了曾经报导过的最大输出功率变换增益的折衷法，实验与模拟结果相当吻合。     

WCDMA系统的功率控制

文章阐述了WCDMA系统无线资源管理中的功率控制,包括功率控制的准则和组成部分以及一般采用的功率控制算法。     

坚实性宽带自适应阵列处理器设计

在这篇文章中，我们提出了一种新的自适应阵列处理器的设计方法．这种方法以输出最小功率为准则，并服从幅度的或功率的等式和不等式约束．约束可以在空域进行，也可以在频域进行．通过调整约束条件，可以方便地得到各种不同的性能指标，如坚实性的宽带波束，高抗干扰性能，简化硬件结构等．     

CDMA系统中一种新的基于MMSE多用户检测的自适应功率控制算法

功率控制技术是CDMA通信系统中克服“远一近效应”，降低多址干扰、增大系统容量的一项关键技术。第三代移动通信系统对功率控制提出了新的研究课题。在本文提出CDMA系统中一种新的白适应功率控制和MMSE多用户检测的联合优化的算法，仿真结果表明，这种新的联合优化算法对提高系统容量，改善系统性能有很大的作用。     

X波段五位移相器的小功率开关HMIC的研制

介绍了一种混合微波组装工艺制造的Ｘ波段ＰＩＮ二极管五位数字移相器和小功率开关ＨＭＩＣ的电路设计和制造工艺，并分析了制造工艺对移相器的影响，提出控制这种影响的方法。用这种控制方法制造的该Ｘ波段ＰＩＮ二极管五位数字移相器和小功率开关ＨＭＩＣ：体积小，可靠性高。     

一种采用混合平衡准则的新功率控制算法

功率控制算法按准则可以分为基于功率平衡准则和基于SIR平衡准则两大主流。基于信干比平衡的功率控制算法存在正反馈问题。基于功率平衡和信干比平衡混合准则的功率控制算法可以解决正反馈问题,但复杂度较高,实现比较困难。提出了一种基于功率平衡和信干比平衡混合准则的功率控制算法。本算法在每次迭代中通过测试接收信号功率和接收信干比,只需要一次判决产生下一周期的发射功率,因此具有易于实现的优点。分析和仿真表明本算法是有效的。     

WCDMA闭环功率控制的研究

本文针对第三代移动通信系统ＷＣＤＭＡ方案,提出了功率控制中的信噪比的测量算法及修正曲线;并在Ｍ１２５多径衰落信道下,以用最低信噪比达到相同通信误码率为准则,对闭环功控中的功率调整步长进行了优化仿真。     

雷达干扰射频隐身特性及自适应功率控制方法

针对战机实施有源干扰时的射频隐身问题,分析了现有干扰功率评估准则的不足,在雷达信号检测模型和侦察截获概率模型的基础上,讨论了"有效干扰"对干扰功率的需求和射频隐身对干扰功率的限制,提出将有效干扰条件下的侦察截获概率作为干扰信号的射频隐身特性表征因子,最后提出了一种结合目标雷达类型、接收信号功率以及本机RCS起伏等因素的干扰功率自适应控制方法。通过对固定功率干扰与不同压制系数下自适应功率干扰时雷达检测概率和侦察截获概率的仿真,表明自适应功率控制能够节约干扰功率,在有效干扰的同时提高干扰的射频隐身能力。     

DOA估计算法评价准则在不同功率入射信号下的修正

针对复杂电磁环境中信号功率对入射信号波达方向（DOA）估计的影响问题进行研究,发现用于DOA估计算法性能分析的经典评价准则对不同功率入射信号存在局限性。针对该问题,首先证明了强信号功率会影响弱信号DOA估计性能,得到强信号功率增加会导致弱信号功率克拉美罗界上升,即弱信号DOA估计的均方根误差增加。然后分析了DOA估计算法的经典评价准则对分辨不同功率入射信号存在的局限性,通过蒙特卡洛实验验证了经典评价准则对分辨不同功率入射信号存在较大误判率,当弱信号信噪比低于5dB时,其误判率大于50%。最后本文提出了DOA估计算法新的评价准则,并仿真证明了新准则较经典准则更适用于分辨弱信号信噪比较低时的不同功率入射信号。所提出的评价准则可为基于空间谱估计的DOA估计算法性能分析提供参考依据。      

Forward Link Power Control Strategy and its Optimum Issue in CDMA Cellular Networks

In this paper, we propose a theoretical method in order to estimate the forward link outage probability and user capacity of a cellular system which are based on IS-95 CDMA standard, especialy impact of power control strategy and voice activity monitoring in the system under long-term fading effects, in which the light and heavy fadings are considered. According to the numerical results obtained in this paper, the power control strategy leads to approximately the threefold user capacity in contrast to the situation without power control strategy. The reults are compared with Interference-to-Signal Ratio (ISR) driven power control scheme[6][9] which can be used only for simulation of the system. The power control strategy not only improves the desired signal to the interference ratio in the reference user's receiver, but also offers uniform service to the user wherever it is located in the cell.     

有限字符输入下AF中继系统安全互信息量分析及功率控制策略

本文针对有限字符输入下多中继通信系统,推导了源和中继节点总功率受限条件下的安全互信息量。在已知理想信道状态信息的条件下,给出了一种基于对窃听节点迫零的波束赋形方案,并设计了一种提高安全互信息量的功率控制策略。针对所提功率控制策略,研究了该策略下目的节点和窃听节点的平均误符号率性能,分析表明该策略在高信噪比下存在误码平层。针对误码平层缺陷,本文提出了一种高信噪比下适当增大源节点发射功率的改进方案。改进方案虽然损失了部分安全互信息量,但换来误符号率的明显改善,消除了功率控制方案的误码平层问题。      

Automatic Uplink Resource Management in Mobile Cellular Networks: A Utility-Based Cooperative Power Control Strategy

This paper proposes a cooperative power control strategy for resource adaptation in mobile network to optimize user uplink transmission power. Our approach is based on a cooperative model using the economic concepts of utility function and the random graph theory. Based on the model, we develop a distributed power control algorithm that maximizes the utilities of all mobile users. Formulating this algorithm as a cooperative strategy, we show the uncertainty and existence of the power control approach with theory of random bipartite graph and utility function. A discussion to the existence of optimal solutions is given. Then a distributed power control scheme is proposed based on the optimal solutions. It is shown by way of simulation that by introducing utility function in the power control algorithm, there is a performance improvement in terms of the utilities that mobile users obtained. Numerical results are presented for the algorithm.     

Adaptive Water-Filling Power Control for Wireless Communications Networks

Power control is an important approach to improve capacity of wireless channels. Provided that the channel state is known at both the transmitter and the receiver, the optimal power control is a water-filling strategy which depends on the channel state. In this work, we establish some properties of the water-filling power adaptation strategy and propose an algorithm for the transmitter to automatically tune the water-filling strategy. Numerical examples are provided to show the effectiveness of the proposed algorithm.     

Open‐loop power control performance in DS‐CDMA networks with frequency selective fading and non‐stationary base stations

In this paper, we study the performance of a simple and easy‐to‐implement distributed power control strategy applicable to direct sequence code division multiple access (DS‐CDMA) networks. The scheme makes use of the received power measurements made on the forward link at individual mobile units to control the transmit powers on their reverse links. The algorithm, which effectively compensates for the slowly varying distance and shadow losses (due to their high correlation on both forward and reverse links), attempts to minimize the effect of fast multipath fading by averaging it out. We adopt a quasi‐analytic approach to estimate the reverse link capacity performance of an open‐loop power control scheme in both a single cell and a multi‐cell environment, and we do this for both a fixed base station and a moving base station scenario. Non‐stationary base stations are typical in tactical and emergency communications scenarios where the base stations could be mounted on moving platforms (e.g., tanks, jeeps, unmanned airborne vehicles). We estimate the capacity degradation, when base stations move relative to other cells, as a function of the amount of cell overlap and the standard deviation of the power control error. We also provide a comparison of the performance of the open‐loop power control strategy with that of a closed‐loop power control strategy.     

Power allocation and call admission control in multi‐class traffic DS‐CDMA systems with imperfect power control

We deal with power allocation (PA) and call admission control (CAC) under imperfect power control (IPC) in the reverse link of direct sequence‐code division multiple access systems for supporting multi‐class traffic. First, we briefly review the optimum PA scheme under perfect power control (PPC) and the CAC scheme subject to an outage constraint on the total composite received power. Then, we analyze the outage degradation due to the power control error when the optimum reference power levels under PPC are used. In order to mitigate the outage degradation, we would modify the reference power levels by incorporating a call dropping strategy and an outage‐lowering strategy into the optimum PA scheme under PPC. Also, we derive a constraint inequality to determine the reverse link capacity under IPC. Finally, through numerical analyses, we compute the modified reference power levels under IPC and evaluate the reverse link capacity under IPC. Copyright © 2006 John Wiley & Sons, Ltd.     

发射端功率控制对MQAM系统误码率性能的改善

自适应发射功率控制是无线通信领域中减小系统误码率、增加系统吞吐量的一项有效技术.对发射端功率控制下MQAM系统的误码率性能进行了研究,得到了MQAM调制时近似最优化的功率分配方案.理论曲线显示,发射端采用功率控制的系统误码率性能将得到一定程度的改善.     

Open‐loop power control performance in DS‐CDMA networks with frequency selective fading and non‐stationary base stations

In this paper, we study the performance of a simple and easy‐to‐implement distributed power control strategy applicable to direct sequence code division multiple access (DS‐CDMA) networks. The scheme makes use of the received power measurements made on the forward link at individual mobile units to control the transmit powers on their reverse links. The algorithm, which effectively compensates for the slowly varying distance and shadow losses (due to their high correlation on both forward and reverse links), attempts to minimize the effect of fast multipath fading by averaging it out. We adopt a quasi‐analytic approach to estimate the reverse link capacity performance of an open‐loop power control scheme in both a single cell and a multi‐cell environment, and we do this for both a fixed base station and a moving base station scenario. Non‐stationary base stations are typical in tactical and emergency communications scenarios where the base stations could be mounted on moving platforms (e.g., tanks, jeeps, unmanned airborne vehicles). We estimate the capacity degradation, when base stations move relative to other cells, as a function of the amount of cell overlap and the standard deviation of the power control error. We also provide a comparison of the performance of the open‐loop power control strategy with that of a closed‐loop power control strategy. This revised version was published online in July 2006 with corrections to the Cover Date.     

电能质量多目标检测策略的应用

根据多目标检测策略,研究开发了大容量的改善电能质量变流器。变流器以TMS320F28335 DSP为控制系统核心,控制算法采用了多目标检测策略。通过在大功率装置上的试验,验证了该检测策略的有效性。该多目标检测策略也大大简化了对多目标电能质量治理装置控制系统的设计,具有很强的实用性。     

采用pq瞬时功率理论的三相电压源变换器的研究

瞬时有功和无功功率理论,即Pq瞬时功率理论,得到了广泛的研究和实际应用。本文基于pq瞬时功率理论,分析了三相有源电力滤波器三种主要控制策略的工作原理,包括瞬时功率恒定策略、电流波形正弦策略、广义Fryze电流控制策略,另外简要分析了三相有源电力滤波器的另一种同步功率传输控制策略,并在三相供电电压平衡和对称的条件下,将pq瞬时功率理论应用到三相电压源PWM整流器中,采用MATLAB/SIMULINK进行较为深入的仿真分析,获得了非常满意的结果。结果表明,相比平均功率理论,采用pq瞬时功率理论,三相电压源变换器具有响应快、控制简单等优点。