CDMA直放站覆盖系统的优化

随着中国联通CDMA网络在全国大规模放号工作的进行,中国联通正在对网络进行扩容和优化以满足客户的要求。在这一过程中,直放站覆盖系统的优化至关重要。1 CDMA直放站覆盖系统的网络优化CDMA直放站覆盖系统的网络优化内容主要包括:直放站功能测试、直放站覆盖区域的路测、测试结果的分析、直放站系统的调整、施主小区基站参数的调整等。1.1 评估与优化的统计参数(1)无线覆盖率: 通过对系统测试,得到直放站覆盖区域内各个地理位置上主导频的Ec/Io和手机的发射功率Tx,用主导频的Ec/Io作为定义前向覆盖范围的尺度,用手机的发射功率Tx来…     

CDMA网络直放站的规划建设与优化

文章介绍了CDMA直放站在规划建设中应注意的问题,分析了直放站对PN规划、邻区规划、容量覆盖的影响,对存在直放站区域的搜索窗设置给出了具体优化建议。     

IS-95 CDMA系统基站导频的规划

前向链路设计是ＣＤＭＡ网络建设的重要环节之一，而前向链路设计的关键在于分配基站的Ｐ码偏置，本文推导了ＰＬＯＴ＿ＩＮＣ的最小取值，ＰＮ码最小的复用距离，并以实际建设的广东省ＣＤＭＡ试验网为例给出了ＰＮ码偏置的分配步骤。     

直放站在CDMA网络中的应用

在CDMA系统的建设中，使用直放站可以扩大信号的覆盖区域，改善通信质量，调配基站话务量。本文在简单介绍直放站原理的基础上，从多个角度对直放站在CDMA网络中的应用做了分析，同时结合实际情况，指出了CDMA直放站在工程建设中需要注意的事项。     

CDMA网络优化浅析

阐述CDMA网络优化需要考虑的几个问题。     

CDMA移动通信网络的优化

首先介绍了网络优化的基本知识,然后以一个边远城镇的CDMA网络为例,通过比较,确定利用光纤直放站形式对网络进行优化的方案,并对其中主要技术指标进行了分析和计算.     

CDMA无线网络的规则方法

CDMA网络无线规划要充分利用好当地的人口、经济、地理等方面的基本信息，同时要体现出当地的特色，如体现出某地经济发展不平衡的特点，体现出某地重点乡镇的发达水平、城乡差距的特点等。CDMA网络无线规划不仅要达到较好的经济效益，同时也要考虑社会效益，要在上述信息的基础上，实现经济效益和社会效益的双丰收。在网络规划前期，需要充分调查以下的信息。     

MapInfo在CDMA无线网络优化中的应用

本文介绍了MapInfo软件在CDMA无线网络优化中的应用,为CDMA无线网络优化中网络数据的后台处理与分析提供了很好的解决方案.     

无线网络优化应注意的几个问题

无线网络优化巳成为日常的工作,网络优化的技术和手段也非常先进，对网络参数的优化已做得非常全面细致，对频率的优化已有很先进的工具和更好的频率复用方式，而我们现在的无线网络优化应细致到一个基站，一个小区，但一些网优人员对基站硬件、直放站、室内分布系统，传输、天馈等了解较少，而这些原因对掉话的影响是很大的，以下对一些典型问题进行分类汇总，供网优人员和维护人员参考借鉴。     

CDMA无线网络掉话分析

掉话率是衡量CDMA无线网络质量的一项重要指标。本文从邻区的设置、PN的规划、搜索窗的设置、直放站的利用、导频污染、强导频现象等方面,分析了掉话的原因,提出解决方案,并给出优化案例。     

浅析联通CDMA网络的优化

1网络优化的重要性经过两年多的建设,中国联通CDMA网络的容量已经达到3500万户,覆盖了全国所有的县、东部和中部地区所有的乡镇、西部地区部分乡镇。随着移动用户数量的剧增,业务种类的丰富,广大用户对网络质量的要求也越来越高,高质量的网络和丰富的业务种类将成为吸引用户的主要卖点。在网络规模初步形成后,网络优化就成为降低运营成本、提高网络质量的主要手段。而网络优化是网络资源有效利用的保障,更是通信企业核心竞争能力的充分体现,所以我们应该树立全网优化的意识及应变的优化思路,通过网络优化工作提高网络运行质量,合理有效地…     

TCP-Aware Channel Allocation in CDMA Networks

This paper explores the use of rate adaptation in cellular networks to maximize throughput of long-lived TCP sessions. We focus on the problem of maximizing the throughput of TCP connections and propose a joint optimization of MAC and physical layer parameters with respect to TCP sending rate. In particular, we propose a simple TCP-aware channel scheduler that adapts the wireless channel rate to changes in the TCP sending rate and explore its performance for both single and multiple concurrent sessions. In the case of a single TCP session, we develop a fluid model of its steady-state behavior in such a system that adapts between two channel rates. Our results indicate that a two-rate scheme improves TCP throughput by 15% to 20% over a system that does not exploit rate adaptation and that little additional benefit accrues from the addition of a third channel rate. Finally, we extend the framework to scenarios where bandwidth is shared by multiple TCP sessions. We propose two channel allocation algorithms and explore their performance through simulation. Our results indicate that TCP throughput is relatively insensitive to either channel allocation algorithm and adaptive rate variation is the dominant factor in performance.     

Optimizing spectral efficiency in multiwavelength optical CDMA system

Prime codes are excellent candidates for use in multiwavelength optical code-division multiple-access (O-CDMA) systems. We show that in an O-CDMA system using two-dimensional single-pulse-per-row codes, a single choice of the number of wavelength channels can. accommodate different numbers of users with maximal spectral efficiency. The optimum single-user-detection spectral efficiency of the system can be reached using AND detection. A fixed-hardware network can readily be adapted in response to changes in the number of users and traffic load.     

CDMA网络优化流程和具体实施过程

本文主要介绍了CDMA网络的优化流程以及具体的操作方法,对优化中出现的问题做了比较详细的分析,并提出了相应的解决措施.     

Downlink Throughput Maximization in CDMA Wireless Networks

We investigate optimum rate assignment scheme maximizing network throughput on the downlink of a multirate CDMA wireless network. Systems employing orthogonal variable spreading factor (OVSF) codes as well as systems employing multiple codes have been studied. Our objective is to maximize the network throughput under constraints on total transmit power, total bandwidth and individual QoS requirements specified in terms of minimum rates. First, users are ordered based on their transmit energy per bit requirements to achieve the target received energy per bit to interference power spectral density ratio at the receivers. Based on the initial ordering, we prove that for systems employing multiple codes, greedy rate assignment yields maximum network throughput. For systems employing variable spreading codes, we show that greedy rate assignment is optimal if the minimum rate requirement of a user is larger than or equal to the minimum rate requirement of any other user with a larger transmit energy per bit requirement. Simulation results verify the superiority of the greedy algorithm under various system and channel assumptions     

Providing Real-Time Service in CDMA Wireless Networks

Medium Access Control (MAC) protocol design plays a very important role in the design of wireless networks. In this paper, we propose a new MAC protocol to provide real-time service for a CDMA wireless network. This protocol has been designed based on the distributed queuing random access protocol for CDMA wireless networks (DQRAP/CDMA). As real-time scheduling schemes have been introduced into the protocol design, the new protocol has an ability to accommodate real-time traffic in the CDMA wireless networks. A series of simulation experiments have been carried out to evaluate the performance of the proposed protocol. The results reveal that the proposed protocol can efficiently provide real-time service to the traffic composed of time constrained messages in the CDMA wireless networks.     

浅谈CDMA网络优化

网络优化的目的是改善网络的通信质量。采用快速有效的网络优化方法,改善网络的性能和服务质量是移动运营商关注的主要问题之一。由于CDMA是干扰受限系统,因此CDMA网络的优化尤为重要。本文简要概述了CDMA无线网络优化的方法及相关措施,对网络优化的准备工作、数据分析以及优化办法进行了相关探讨。     

Nonuniform Spectral Phase Encoding in Optical CDMA Networks

We utilize a nonuniform encoding scheme for spectral phase encoding in optical code-division-multiple-access networks. This method improves the orthogonality of encoded waveforms between multiple users under synchronous transmission by compensating for the nonideal spectral shape of the subpicosecond mode-locked laser pulse source. Simulation results demonstrate five orders of magnitude of bit-error-rate reduction compared with the traditional uniform encoding scheme     

通过优化预分配算法提升CDMA数据能力

提出采用优化预分配算法来提升CDMA数据能力。实施效果表明在前向平均速率、SCH话务量、空口前向流量、闲基站和忙基站服务能力、业务低速和高速比例等5个方面都得到了显著提升。