TD-SCDMA基站和WCDMA基站的共存分析

主要探讨了WCDMA系统与TD—SCDMA系统基站间的共存问题，并从邻频干扰的角度进行了深入的分析；采用确定性计算方法和静态仿真方法研究TD—SCDMA基站对WCDMA基站产生的邻频干扰，并分析了采用智能天线后带来的改善。     

WCDMA与TD-SCDMA系统共存时的干扰研究

WCDMA和TD-SCDMA系统如果共存时,由于邻频会产生一定的干扰,文章就这两个系统共存进行了可行性分析,并提出了解决方案。     

WCDMA与TD—SCDMA系统共存时的干扰研究

WCDMA和TD—SCDMA系统如果共存时，由于邻频会产生一定的干扰，文章就这两个系统共存进行了可行性分析，并提出了解决方案。     

基于Inmarsat-B岸船数据传输误码原因分析

Inmarsat网络是目前运行最为稳定的全球覆盖、全天候卫星通信网络。在海上船舶岸船通信中,由于特殊业务的需要,构建了一种基于Inmarsat-B系统的终端对终端多路数据复接和传输的通信系统。根据此类系统存在的经常性突发误码、建链困难等问题,从系统链路的构成、时钟同步关系和信道干扰等方面进行了机理分析,提出了更改链路结构、设置数据缓冲、采用新型终端和加强天线性能等解决方案及措施,以期提高系统可靠性和通信质量。     

5G NR FDD与WCDMA系统共存研究

为推动5G在中频段的重耕,研究了中频段NR FDD系统与WCDMA系统在相同地理区域邻频共存时的系统间干扰造成的性能损失,分析了在不同功率参数、不同拓扑结构、AAS/NON-AAS 2种天线模型下,4个干扰场景的仿真结果.最后给出NR FDD系统与WCDMA系统共存建议以及共存措施.     

WCDMA与TD-SCDMA基站之间的干扰分析研究

针对WCDMA系统与TD-SCDMA系统基站之间的共站、共存问题，从干扰的角度进行了深入的分析。在干扰分析的基础上，得出了WCDMA和TD-SCDMA基站能否共存的结论，并给出了两者共站、共存的建议。     

一种710MHzLTE天线的去耦合分析

为了提高天线的容量和发射接收速率,LTE通信系统使用了MIMO天线。由于移动终端上空间有限,多个天线间存在较大耦舍,天线的辐射效率和通信容量会降低。为了解决这一问题,从S参数的角度推导出了天线的正交辐射模式,提出了通过加入180。耦舍器来降低多个天线间耦合的方法。使用HFSS和ADS对设计好的710MHz天线进行联合仿真,结果显示加入耦舍器后,两个天线间的耦合明显减小。这种设计使得该天线可以很好地应用于LTE通信系统的移动终端。     

多制式基站探测终端设计与实现

多制式基站探测终端基于S3C2440设计而成,使用内存映射方式扩展多路串行通信接口,内置多制式通信模块。将该终端置于移动监测车辆之中,在监测车辆移动过程中,终端实时、周期性监测热点所在区域三大运营商不同制式的无线网络信号,包括GSM,CDMA,WCDMA,TD-SCDMA,并将采集获得的GPS信息、基站参数、信号强度等上传至管理软件,管理软件在线分析获取监测区域全网信号图谱。该系统的使用填补了目前无线通信全网实时同步监测的市场空白,丰富了无线网络监测手段。     

WCDMA/GSM共址时的干扰及其隔离度分析

文章首先分析了WCDMA与GSM系统共站址时的主要干扰类型，给出了各种干扰的数学计算模型，然后详细阐述了WCDMA与GSM系统相互之间的干扰情况，得出了WCDMA与GSM共址时所需的隔离度及天线隔离要求，并给出了工程中的解决方案     

PHS和NWCDMA无线网络共存研究

目前，中国电信和中国网通运营的PHS系统主要使用1900-1920MHz频段，与WCDMA规划的FDD频段：1920～1980MHz／2110-2170MHz的上行频段1920～1980MHz相邻(见图1)，因此PHS系统与WCDMA系统之间可能存在干扰。在以后的商用网络中，WCDMA系统与PHS系统共存是一个必然的趋势，因此必须解决PHS系统与WCDMA系统之间的干扰问题。     

Performance of receive diversity and LMMSE chip equalization in WCDMA HSDPA network

More advanced receiver structures than the conventional single antenna Rake can be used to improve the signal-to-noise (SNR) ratios, which is especially beneficial in order to utilize the high bit rates provided by the HSDPA concept in Wideband Code Division Multiple Access (WCDMA) network. In WCDMA system, orthogonal Walsh–Hadamard sequences are used as channelization codes. In frequency-selective fading channels the orthogonality of channelization codes disappears and intra-cell multiple access interference (MAI) arises. In order to mitigate the effect of MAI, chip-level equalization has shown to be a simple and effective solution. The effectiveness of chip equalization, however, degrades at the cell borders where the inter-cell interference dominates rather than MAI. Dual antenna reception is a straight-forward solution to mitigate that performance drop. In this paper, we present an analysis of the expected gains of advanced receivers over conventional single antenna Rake receiver in realistic situations by using a dynamic WCDMA system-level tool. Considered advanced receivers include single and dual antenna Linear Minimum Mean Squared Error (LMMSE) chip-level equalizers and dual antenna Rake receiver. The network performance with advanced receivers is studied also from a more practical point of view by assuming that the penetration of advanced HSDPA terminal receivers is gradually increased in the network.     

Simulation,implementation and performance evaluation of a diversity enabled WCDMA mobile terminal

Smart antenna array technology has been shown to greatly improve the performance of wireless communication systems. In this article, we describe the impact of smart antenna array processing at the mobile terminal for Wideband Code Division Multiple Access (WCDMA) cellular networks. Using system simulations we demonstrate the quality of service, network coverage, and network capacity improvement provided by a WCDMA dual antenna receiver and we establish a relationship between this improvement and the link level performance. We then describe a receiver architecture for a dual antenna WCDMA mobile receiver. The proposed receiver was implemented, as part of a complete mobile terminal solution, in an ASIC using a 0.18 μm, 1.8 V CMOS technology. The ASIC was integrated with RF, analog and digital components in a PCMCIA card form factor. The PCMCIA is a 3GPP compliant user equipment and has been submitted to standardized performance and conformance tests. Experimental measurements gathered with the PCMCIA card illustrate the impact of a diversity enabled mobile data terminal on the link level performance. For various propagation environments and transmission data rates, improvements in the range of 2.7 – 10 dB in the required DPCH I _c/I _or for a 1% Block Error Rate (BLER) were observed. These measurements are within 1.4 dB of the ideal link level simulations which indicates that the predicted improvement at the network level should also materialize. The results presented in this paper show the tremendous potential of smart antenna arrays in 3G WCDMA cellular networks and establish diversity as a viable solution for high-speed cellular communications.     

TD-SCDMA系统特点及发展分析

讨论了TD-SCDMA系统的优势及特点,并着重阐述了TD-SCDMA系统所应用的联合检测、智能天线、动态信道分配、上行同步技术及接力切换等关键技术.对于标准演进后的核心技术如HSDPA、HSUPA的进展也做了概括性的介绍,并对TD-SCDMA技术的发展方向作了一定的分析.最后简要讨论了TD-SCDMA与WCDMA系统的干扰和共存,回顾了TD-SCDMA发展的成绩,提出了对未来TD-SCDMA产业的展望.     

Study on coexistence between DCS1800 and TDD-LTE systems in multi-mode terminals

It's well known that the mobile stations will comprise a wide range of radio access technologies (RAT), providing user with flexible and efficient access to multi-media service and high data rate communications. Although much work has been done for coexistence analysis between different systems base stations (BS), most of them have not addressed the interference within multi-mode terminal. Hence, for filling the gap, The authors in the article present coexistence studyies of digital cellular system at 1 800 MHz (DCS1800) and time division duplex long term evolution (TDD-LTE) network in multi-mode terminal with multi-service provisioning. A new system model for coexistence was introduced and how deterministic analysis can be done within the terminal was explained. The interference evaluation model was given based on relations between reference sensitivity and signal-to-noise ratio (SNR), which is also deduced. The system simulation methodology was provided and assumption used in simulation was given. Simulation results were shown with different system parameters. Numeric results indicate that multi-mode terminal is mainly affected by local interference. The minimum antenna isolation required for a health system operation was provided.     

3G共存干扰分析

在WCDMA和CDMA2000组成的共存系统中,邻频干扰是影响系统性能的重要因素,分别从上下行链路两个方面理论分析了由CDMA2000系统引起的邻频干扰对WCDMA系统产生的影响。仿真结果表明,基站与移动台之间的距离、干扰移动台数、两系统之间的保护带宽都将不同程度地影响WCDMA基站的最小允许接收功率和WCDMA移动台的SIR,从而导致系统容量的下降。     

WCDMA室内覆盖系统规划设计方法

针对当前2G和3G共存的实际情况,讨论了WCDMA与现有2G系统共建的思路;针对2G在兼容WCDMA方面的优缺点进行了分析;讨论了WCDMA与2G共建的合路方式,馈线、天线的改造等方法;详细分析了WCDMA与其他系统同接入一套分布系统时抑制杂散、阻塞、互通干扰所需的隔离度。     

M-WiMAX与WCDMA系统共存问题及M-WiMAX系统子信道分配算法研究

论述了世界微波互用接入（M-WiMAX）系统对和宽带扩频多址接入（WCDMA）系统之间的共同存在问题。为了减少M-WiMAX系统对 WCDMA系统的干扰，我们在M-WiMAX 的基站端使用了自适应发送端波束成形（Transmit Beamforming, TxBF）技术。于此同时，我们提出了相应的邻信道干扰模型以分析TxBF技术在降低邻近信道干扰中的增益。并且，我们提出了一种新型的子信道分配方法用来提高M-WiMAX 系统的数据吞吐率。为了验证提出的算法，我们建立了系统层仿真平台并使用蒙特卡罗仿真的方法来验证本文中提出的算法。