QoS‐Guaranteed Multiuser Scheduling in MIMO Broadcast Channels

This paper proposes a new multiuser scheduling algorithm that can simultaneously support a variety of different quality‐of‐service (QoS) user groups while satisfying fairness among users in the same QoS group in MIMO broadcast channels. Toward this goal, the proposed algorithm consists of two parts: a QoS‐aware fair (QF) scheduling within a QoS group and an antenna trade‐off scheme between different QoS groups. The proposed QF scheduling algorithm finds a user set from a certain QoS group which can satisfy the fairness among users in terms of throughput or delay. The antenna trade‐off scheme can minimize the QoS violations of a higher priority user group by trading off the number of transmit antennas allocated to different QoS groups. Numerical results demonstrate that the proposed QF scheduling method satisfies different types of fairness among users and can adjust the degree of fairness among them. The antenna trade‐off scheme combined with QF scheduling can improve the probability of QoS‐guaranteed transmission when supporting different QoS groups.     

ASON容量的多种因素影响分析

探讨了影响ASON容量的多种因素,包括网络生存性、业务等级、网络拓扑和业务路由条件,并通过网络案例,使用ASON规划软件,对网络容量进行了量化计算和分析对比。针对在规划中如何处理这些影响因素以保证合理的网络容量规划,提出了一些建议。     

GSM网络寻呼承载能力及突发应对策略分析

着重分析了GSM网络Um接口和Abis接口的寻呼承载能力,阐述了寻呼容量对位置区承载话务量的限制,以实例说明了寻呼量突发的特点,并提出了多种应对寻呼量突发的策略。     

基于VISSIM仿真技术的小区交通开放对周边道路通行影响的探究

主要研究居民小区交通开放后对道路通行能力的影响.基于模糊理论的车辆跟驰模型,利用VISSIM仿真软件对不同类型小区周围的道路交通与交叉路口的车辆通行情况进行仿真,分析了仿真获得的数据,得出小区出口所对应路段的理论通行能力.最后根据研究的成果,向相关部门提出合理化建议.     

Reversible data hiding based on RSBEMD coding and adaptive multi-segment left and right histogram shifting

By leveraging the secret data coding using the remainder storage based exploiting modification direction (RSBEMD), and the pixel change operation recording based on multi-segment left and right histogram shifting, a novel reversible data hiding (RHD) scheme is proposed in this paper. The secret data are first encoded by some specific pixel change operations to the pixels in groups. After that, multi-segment left and right histogram shifting based on threshold manipulation is implemented for recording the pixel change operations. Furthermore, a multiple embedding policy based on chess board prediction (CBP) and threshold manipulation is put forward, and the threshold can be adjusted to achieve adaptive data hiding. Experimental results and analysis show that it is reversible and can achieve good performance in capacity and imperceptibility compared with the existing methods.     

Evaluation of the Thermal Comfort of a Thermoelectric Ceiling Cooling Panel (TE-CCP) System

This present work evaluates the cooling performance and thermal comfort of a thermoelectric ceiling cooling panel (TE-CCP) system composed of 36 TE modules. The cold side of the TE modules was fixed to an aluminum ceiling panel to cool a test chamber of 4.5 m³ volume, while a copper heat exchanger with circulating cooling water at the hot side of the TE modules was used for heat release. Thermal acceptability assessment was performed to find out whether the indoor environment met the ASHRAE Standard-55's 80% acceptability criteria. The standard was met with the TE-CCP system operating at 1 A of current flow with a corresponding cooling capacity of 201.6 W, which gives the COP of 0.82 with an average indoor temperature of 27°C and 0.8 m/s indoor air velocity.     

Capacity and SER Analysis of MIMO MRC Systems in an Interference-Limited Environment

The effect of co-channel interference (CCI) is considered in multiple-input multiple-output (MIMO) systems employing maximal ratio combining (MRC) under independent and identically distributed Rayleigh fading. Closed-form capacity and symbol error rate expressions are presented to evaluate the performance without any numerical integrations or statistical simulations. The analytical results are compared with Monte Carlo simulations and the good agreement is obtained.

智能天线非理想波束赋形对TD-SCDMA系统性能的影响

在实际的无线网络中,由于无线信道的复杂性以及DOA估计的误差,会导致智能天线系统的波束赋形出现一定程度的偏差。该文通过分析智能天线系统的原理,提出了非理想波束赋形智能天线对系统性能影响的研究方法,研究了智能天线系统的鲁棒性以及不理想波束赋形的智能天线对TD-SCDMA系统性能的影响。理论和仿真结果表明,波束赋形的准确度直接影响移动通信系统的性能,系统所能容忍的波束赋形偏差有一个固定的门限值,该门限值随着系统负载的增加而减小。     

WCDMA与GSM无线网络规划比较

首先介绍了WCDMA和GSM系统不同的技术特点并进行了比较,在此基础上,结合无线网络规划的一般流程,对这两种系统在无线网络规划方面进行了分析比较,研究了他们之间的异同。通过这种分析和比较,借鉴GSM网络比较成熟的网络规划技术和经验,对于即将开始进行的第三代移动通信网络规划具有一定的参考价值。     

基于图形理论的Ad Hoc网络容量研究

网络容量是评估无线Ad Hoc网络性能的重要参数。本文的目的是研究如何使Ad Hoc网络容量达到最大。文章从一个全新的角度考虑Ad Hoc网络的建模，核心思想是Ad Hoc网络节点间的传输具有有限资源（包括带宽、功率等），在同等条件下若能使网络传输消耗资源最小，则网络容量迭到最大。建立了资源消耗的线性规划方程，利用图论的方法对问题求解并对算法进行改进，得到相应的路由策略。由仿真试验说明修改后的算法更加高效。