通话时长模型的建立和应用

１概述在电信网管理中 ,通话时长是研究话务理论的重要参数 ,同时也是话务统计中的一个重要项目。通话时长是指从被叫用户摘机开始 (或被叫Ｍｏｄｅｍ应答开始 )直至主、被叫中任意一方挂机为止的时间。在电话网规模基本稳定之后 ,运营商的重点将从网络建设转变为向话务量要效益 ,因而充分了解通话时长的规律 ,对网络分析和决策有重要意义。根据调查 ,目前连入Ｉｎｔｅｒｎｅｔ的用户有８０%是通过电话网拨号接入的。因此 ,目前的公众电话交换网(ＰＳＴＮ)承担了两种主要的业务流 :一是普通语音通话业务 ;二是拨号上网的数据业务。其中后者…     

移动通信用户单机通话时长变化趋势研究

本文通过分析移动通信业务生命周期的不同阶段，各项因素影响力的变化，得出移动通信用户单机通话时长的变化趋势。     

对数正态概率纸的自动生成和分布参数的自动提取

采用对数正态概率纸可以直观地判断一组数据是否服从对数正态分布，而且还可以得到对数正态分布参数，即对数均值和对数标准差。介绍对数正态概率纸自动生成和分布参数自动提取的方法以及据此开发的软件。与手工使用概率纸的常规方法相比，采用所开发的软件不但使用简单、方便，而且能提高计算结果的精度。     

关于正态随机变量函数的正态性

讨论了正态随机变量函数的分布性问题，给出了若干非线性函数，使得复合随机变量仍然服从正态分布。在某些特定条件下，给出了使得复合随机变量服从正态分布的充要或充分条件，对于更一般的情况，提出了若干未解决的问题。     

对数正态分布寿命数据分析的LNLSD软件包原理及其应用

1 引言 机械产品的疲劳寿命和部分电子产品的寿命往往是服从对数正态分布的,可修复产品的维修时间也可以用对数正态分布描述。所以对数正态分布在可靠性工程中有广泛应用。其分布密度函数为     

Performance analysis of cognitive radio networks with generalized call holding time distribution of secondary user

In cognitive radio networks (CRNs), spectrum handoff probability and expected number of spectrum handoffs are important parameters in the evaluation of network performance and design. This paper presents an analytical model for spectrum handoff probability and spectrum handoff rate for CRNs under general distribution of call holding time of secondary users (SUs). The standardized analytical forms of spectrum handoff probability and handoff rate of secondary network under negotiated scenario are derived for a complete service call duration. The effect of mobility parameters: departure rate of SUs (\(\upmu )\) and departure rate of spectrum holes (\(\uplambda )\) on spectrum handoff are also reported in this paper. Extensive results for all the proposed analytical models are obtained and presented in this paper. Analytical results show that exponential and Erlangian distribution functions are not suitable for call holding time of SU in the analysis of spectrum handoff in CRNs. Moreover, the superiority of lognormal distribution function ascertains its use for call holding time of SU in spectrum handoff estimation for better CRN performances. The Monte-Carlo simulation is also performed for spectrum handoff probability to validate the analytical model.     

Modeling PCS networks under general call holding time and cellresidence time distributions

In a personal communication service (PCS) network, the call completion probability and the effective call holding times for both complete and incomplete calls are central parameters in the network cost/performance evaluation. These quantities will depend on the distributions of call holding times and cell residence times. The classical assumptions made in the past that call holding times and cell residence times are exponentially distributed are not appropriate for the emerging PCS networks. This paper presents some systematic results on the probability of call completion and the effective call holding time distributions for complete and incomplete calls with general cell residence times and call holding times distributed with various distributions such as gamma, erlang, hyperexponential, hyper-erlang, and other staged distributions. These results provide a set of alternatives for PCS network modeling, which can be chosen to accommodate the measured data from PCS field trials. The application of these results in billing rate planning is also discussed     

Soliton transmission in telecommunication networks

Erbium-doped fiber amplifiers are a major breakthrough for soliton communication. Most of the difficult problems preventing soliton communication recently were solved using erbium-doped optical fiber amplifiers (EDFAs). Progress in optical soliton communication has been very rapid, since the invention of the 1.48 μm laser diode pumped EDFA, mainly because of its great potential for high-speed communication. This article describes how optical soliton communication has been established, together with the recently developed "soliton control" technique     

Revenue optimization of telecommunication networks

The optimal routing and dimensioning of circuit-switched networks operating with call revenues is examined, and F.P. Kelly's (1988) model is extended in two directions. First, the formulation is transformed in such a way that the optimality equations are significantly easier to derive, and another interpretation of Kelly's induced costs is given. Alternative routing is introduced, the corresponding values for the induced costs and the net path revenue are given, and it is shown that the optimal routing is given by an equal-revenue rule. It is also shown that the dimensioning aspect is easily decomposed into individual link dimensioning problems if the fixed-point multipliers are known. Some results for networks operating with state protection are presented to show that the method also works quite well for networks with heterogeneous traffic     

WDM applications in broadband telecommunication networks

Network applications of multichannel wavelength-division multiplexing (WDM) techniques are considered. The photonic technologies that will be critical to future systems using WDM are reviewed. Both interoffice and subscriber loop architectures that utilize the unique properties of WDM to achieve important advantages over more traditional network designs are presented. Several experimental demonstrations that illustrate how these architectures can be realized with currently available components are described     

CDMA网络语音呼叫接续时长的专项优化及测试分析

介绍了CDMA网络语音呼叫接续时长测试的方法，分析了影响CDMA网络话音呼叫接续时长的主要原因，从无线和交换侧总结出了一些有效缩短CDMA网络语音呼叫接续时长的优化方法。     

Future trends in digital telecommunication transmission networks

New technology is needed by digital transmission networks for the increased bandwidth, performance and reliability requirements of existing and future telecommunication services, such as broadband ISDN. Increased flexibility, automation and control are also major issues being addressed. The combination of these factors has led to the development of synchronous digital hierarchy (SDH) networks to replace existing asynchronous networks during the 1990s. These issues are reviewed and further developments to bandwidth-transparent optical networks indicated for the twenty-first century     

Configuring express pipes in emerging telecommunication networks

Over the past few decades, telecommunication networks have been designed and implemented to support a wide variety of services, including the integration of a customer's voice, data and video communication requirements. Rapid advances in VLSI technology, coupled with declining costs of fiber-based transmission systems, have resulted in high speed, broadband digital networks capable of transporting hundreds of megabits per second. At the same time, a growing number of business customers have expressed the need for controlling and re-configuring their private networks themselves, to better match their business needs. In digital networks, a key component in allowing this flexibility is the establishment of intelligent Digital Cross-Connect Systems (DCS). With DCS, network re-configuration, including bandwidth allocation and topology changes, can be made on a near real time basis, or be scheduled on a reservation basis to take place once (or multiple times) in the future. In this paper, we study the application of digital cross-connect systems in packet switched networks. These systems allow the designer to configure express pipes or direct links between source—destination pairs that have high communication traffic requirements. Since express pipes are configured by borrowing channels from the underlying, leased, backbone network, establishing a direct link reduces the number of free channels available for regular switched traffic, and consequently have the potential of increasing queueing delays. We formulate the problem of judiciously selecting express pipes as a 0/1 nonlinear integer programming problem, that seeks to minimize overall network delay. An efficient Lagrangian relaxation based solution procedure is proposed. Results of computational experiments with the proposed solution technique are also reported.     

Proposed use of rearrangement in multiexchange telecommunication networks

Rearrangement of connections can eliminate blocking in switching networks in exchanges. It is proposed to apply this principle to trunks in multiexchange networks. It is shown for two simple networks that rearrangement eliminates blocking and provides a better grade of service than conventional automatic alternative routing. In more complex networks, rearrangement should enable fewer trunks to be provided.     

在电信网中传送IPTV的可行性研究

主要介绍了在电信网中传送IPTV的基本参考模型,总结概括了IPTV业务的特点,并针对其特点提出了IPTV网络解决方案.