LTE网络容量优化方法研究

介绍了LTE网络无线帧结构,对LTE网络覆盖与容量优化的目的、优化参数以及优化流程进行了详细阐述。针对小区间干扰问题,使用有效的频率复用结构和合理的实时调度算法来提高整个 LTE 小区总的吞吐量。LTE网络容量优化可以有效地提高了LTE网络系统的容量以及覆盖能力。     

大唐移动LTE网络结构分析解决方案

在大唐移动与中国移动设计院以及多家省市公司开展的联合研究之中,大家形成了这样的共识:LTE网络性能是受限于其网络结构的。具体来说:一是随着负荷增加,系统内同频干扰越来越严重;二是市区话务密集区重叠覆盖严重,小区干扰严重;三是干扰分析时缺乏可度量的指标参数;四是TD-S到TD-L升级方案中需要较复杂的联合优化。以上这些问题,大唐移动在长期的研究中形成了自己的一些观点,提出了三种关于网络结构优化的解决方案,第一个是精确规划的方案,第二     

城区LTE网络质量提升优化方案

针对城区LTE网络存在的质量问题,提出对超远覆盖站点、新建站点和超近站点进行结构优化,对基础参数、互操作参数和功率调整进行参数优化,通过美化天线、天馈配置调整、天面整改,通过PCI(物理小区标识)优化和网内外干扰排查,通过告警排障、隐性故障发现和持续监控进行故障点整改等方法提升网络质量,给出提升网络质量的建议,有利于促进LTE优化工作高效开展。     

LTE高倒流小区的网络分析与解决

针对LTE(长期演进)高倒流小区,结合日常优化实践经验,系统性整理LTE高倒流小区的分析定位方法。针对参数配置不合理导致用户无法滞留LTE网络及LTE无线环境不满足用户使用两大类问题,进一步分解归类为参数不合理、故障、弱覆盖、过覆盖四项症结,并从参数优化、故障处理、覆盖提升三个层面阐述盲重定向及最小接入电平优化、异系统互操作参数优化、故障处理策略、LTE小区功率提升、新建站点及结构优化措施等实地优化方案。     

LTE与EV-DO互操作性能研究

分析了LTE与EV-DO数据业务互操作方案,非优化切换方案、流程和相关参数,并对非优化切换时延、切换成功率进行实测分析,与脱网重选时延进行对比,提出LTE数据业务互操作方案实施策略与建议,提升用户业务体验.     

LTE干扰分类和优化方法探究

本文主要对LTE网络中的干扰理论进行了探讨,并通过实例阐述了LTE干扰优化思路和方法,以提高LTE网络优化效率.     

多小区多用户MIMO系统干扰对齐的优化

多小区多用户MIMO系统中存在小区间以及小区内的干扰,传统方法提出的干扰对齐只针对2个小区或者小区内的干扰进行对齐,缺乏对小区间的干扰进行对齐处理.针对这一问题,提出了一种多小区多用户的干扰对齐优化方案,采用基于机会调制算法进行干扰对齐模式优化,不仅能够简化计算、提高量效率,而且能够消除多小区间和小区内的干扰,获得最佳的容量和多用户分集增益.     

LTE中频率复用改进算法研究

下一代蜂窝系统中通过频谱复用来克服小区间干扰已成为当前研究热点.针对LTE小区间干扰协调问题,重点讨论比较了几种频率复用方案,并提出一种自适应的部分频率复用优化方案和具体实现算法,仿真表明该算法能显著改善小区边缘用户的吞吐量性能和公平性参数.     

TD-SCDMA网优专家系统中的干扰矩阵应用

通过基于MR和扫频数据建立干扰矩阵进行频率分配方案的方法已经在无线网络频率优化工作中应用,TD-SCDMA网优专家系统将干扰矩阵中得到的小区相关性做为一种数据源应用到优化向导流程中.     

LTE小蜂窝基站系统干扰抑制技术研究及分析

LTE小蜂窝基站系统干扰抑制技术是提高网络信号质量、提升小区容量的关键技术,对网络覆盖能力和系统网络优化具有十分重要的意义。分别列举了小蜂窝基站系统和小蜂窝网络的干扰抑制技术分析,对LTE小蜂窝基站的建设提出了参考建议。     

LTE同频干扰环境下干扰抑制检测算法的研究

基于上行干扰抑制合并技术（IRC）提出了两种干扰检测算法。第一种改进方案需要预先知道目标小区和干扰小区信道状态信息,第二种改进方案在不知道目标小区和干扰小区信道状态信息的情况下,通过盲估的方法进行计算。这两种算法都能有效抵御同频干扰,并减少误码率。     

Research on uplink coordinated transmission schemes in LTE-advanced systems

The investigation of inter-cell interference mitigation techniques is a key area in wireless communications.Coordinated multiple points(CoMP) transmission/reception is a candidate technique for interference cancellation in 3GPP LTE-Advanced system.However,the coordination scheme in CoMP remains a key research problem to be solved,which will have a strong influence on the performance of CoMP.In this paper,a novel coordinated transmission scheme is proposed for the uplink LTE-Advanced system.In our scheme,several base transceiver stations(BTS) and users are selected as coordination partners which form a CoMP cluster.Joint processing is used at the receiver to mitigate interference.From the perspective of coordinated partner selection,our scheme can be divided into static and dynamic coordination which are both considered to fully exploit the throughput gain of CoMP.The proposed schemes are evaluated by system level simulation and compared with the conventional LTE system based upon single cell processing.Our simulation results demonstrate that the proposed schemes attain superior performance as opposed to the conventional system in terms of cell average and cell edge throughput.     

5G NR上行干扰问题研究

根据中国5G NR的频率使用方案,本文首先重点分析了2.6 GHz频段与4.9 GHz频段上5G NR上行面临的干扰风险,为5G NR规避相关干扰提供指导.然后通过外场干扰测试,掌握了5G NR网络性能与干扰强度间的关系,给出了全频带严重干扰时的5G NR干扰门限建议和NSA组网时的LTE锚点受扰门限建议.根据上述研究结果,本文提出了适合SA和NSA两种组网方式的5G NR干扰分析方法,为5G NR干扰分析的集中化和自动化提供指导.     

Coverage and capacity optimization in LTE network based on non-cooperative games

As to provide the optimal coverage and capacity performance,support high-data-rate service and decrease the capital expenditures and operational expenditures(OPEX)(CAPEX) for operator,the coverage and capacity optimization(CCO) is one of the key use cases in long term evolution(LTE) self-organization network(SON).In LTE system,some factors(e.g.load,traffic type,user distribution,uplink power setting,inter-cell interference,etc.) limit the coverage and capacity performance.From the view of single cell,it always pursuits maximize performance of coverage and capacity by optimizing the uplink power setting and intra-cell resource allocation,but it may result in decreasing the performance of its neighbor cells.Therefore,the benefit of every cell conflicts each other.In order to tradeoff the benefit of every cell and maximize the performance of the whole network,this paper proposes a multi-cell uplink power allocation scheme based on non-cooperative games.The scheme aims to make the performance of coverage and capacity balanced by the negotiation of the uplink power parameters among multi-cells.So the performance of every cell can reach the Nash equilibrium,making it feasible to reduce the inter-cell interference by setting an appropriate uplink power parameter.Finally,the simulation result shows the proposed algorithm can effectively enhance the performance of coverage and capacity in LTE network.     

TD-LTE与WLAN共室分系统干扰分析与研究

随着TD-LTE与WLAN系统共室内分布成为一种必然趋势,二者之间在2.4 GHz邻频组网所面临的干扰也成为焦点问题。在分析了TD-LTE与WLAN系统共室分所面临的杂散干扰、阻塞干扰和互调干扰的基础上,进行了实际的WLAN与LTE共室分干扰测试和独立部署干扰测试,并对测试结果进行分析,提出了有效的干扰规避方案,重点分析了采用合路的方案。     

Optimization and efficient detection of primary synchronization signal for multi‐beam satellite‐LTE systems

A new design of primary synchronization signal (PSS) sequences and an efficient detection algorithm for multi‐beam satellite long‐term evolution (LTE) systems are investigated in this paper. First, a transmit‐timing adjustment method is proposed to reduce the large time difference of arrival of received signals from different satellites. Then, using the particular subcarrier mapping scheme of LTE, original Zadoff–Chu sequences are generalized to obtain more candidate sequences with good correlation properties. Later on, choosing an optimal subset from these candidate sequences, new PSS sequences for seamless global coverage multi‐beam satellite‐LTE systems are obtained. Subsequently, an efficient synchronization and low complexity PSS detection algorithm using interference cancellation method is presented. Finally, simulation results verify the effectiveness of the proposed scheme. Copyright © 2015 John Wiley & Sons, Ltd.     

基于移动信道中速数据流的高健壮性二元网络传输编码调制方案研究

在第三代及第四代移动通信技术中,通信网内数据存量及流量主要以中速数据为主。但由于移动通信技术的特性,在数据传输过程中,信道干扰因素非常强烈,从而直接导致网络数据传输的可靠性大大的降低。而当前网络编码调制技术主要采用了单一的网络编码矢量量化技术,不仅忽略了信道干扰因素,而且对全部的中速数据采用等级保护模式,在移动信道中速数据传输过程误码率性能不强。对此,本文设计了基于移动信道中速数据流的高健壮性二元网络传输编码调制方案。将信道干扰因素和分级保护思想加以引入,提出了联合最佳准则ROBS-C(The Rule Of Based Source And Channel) 分级保护DLP(Divided Level of Protection)的调制方案,兼顾了量化性能和误码性能两个方面。仿真实验表明：本文方案在低信道扰码的场合下量化性能优良;且在强信道扰码情况下,比单一因素的时候误码率低,从而有效的可以面对实际的移动信道下低 /高信道扰码交替的信道状况,能够更好的适应移动通信的要求。     

LTE网络用户感知速率提升策略研究

用户感知速率是LTE网络带给用户的最直观体验,本文引入Throughput速率作为评价用户感知速率的指标。通过对低速率小区的指标分析发现,导致用户感知速率低的主要原因为覆盖不合理、小区高负荷以及高干扰。通过对以上网络问题的优化,可以明显提升用户感知速率,改善网络质量。     

Throughput and cost‐efficient interference cancelation strategies for the downlink of spectrum‐sharing Long Term Evolution heterogeneous networks

In a heterogeneous network (HetNet), small cells such as femtocells considered in this work are deployed jointly with macrocells. This new cells' layer, when added to the network, generates interference, which could hamper neighboring macro‐user equipment (MUE) and femto‐user equipment (FUE) transmissions. In fact, this interference results in degradation of the network performance. In this paper, we propose a downlink interference cancelation (DL‐IC) strategy for spectrum‐sharing Long Term Evolution (LTE) HetNet. This DL‐IC strategy aims to reduce the interference impact on users by optimizing their received signal to interference plus noise ratio (SINR) using new utility functions for both FUEs and MUEs. These utility functions allow relaxation of the cancelation ratios in order to reduce implementation complexity while maximizing SINR, QoS, and throughput. We support by different system‐level simulations that both global network performance and user experience in terms of total throughput and received SNR or link‐level throughput, respectively, are significantly enhanced. Throughput gains achievable by the new DL‐IC strategy can reach as much as 200% against a homogeneous LTE network without IC along with an extra 48% per additional femtocell base station against a basic spectrum‐sharing LTE HetNet without IC. These performance figures are shown to surpass those achieved by interference avoidance techniques using either power or frequency resource allocation. Copyright © 2014 John Wiley & Sons, Ltd.     

移动卫星系统与LTE网络间干扰共存性能的研究

The interference coexistence performance between the systems of a Long Term Evolution (LTE) network and Mobile Satellite Service (MSS) system, both of which work around the frequency of approximately 2 GHz according to the bandwidth allocation in China, is proposed in this article. The related background of an MSS system and the common terminologies are introduced. Further, the coexistence scenarios of different coverage situations shared by the two systems are discussed. The interference impact of an MSS transmission on an LTE system is evaluated using a specific Monte Carlo method. Finally, simulation results show that although no crucial issues for the coexistence of an LTE downlink and the MSS are observed, the LTE uplink suffers a considerable amount of interference from the MSS transmission. Given the insufficient isolation between LTE and MSS existing networks, and the rapid advance in the field of LTE, problems may emerge in the near future. Further, this article can be of sig-nificance in providing reference for frequency spectrum planning in the existing LTE net-works.