TD-LTE基站物理层下行链路设计与实现

发布时间：2018-01-05 23:21

本文关键词：TD-LTE基站物理层下行链路设计与实现　出处：《中国科学技术大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着科技发展和人类需求不断增长,移动通信已经完成了三次变革,目前正在进行第四次变革,相比3G,第四次变革演进了无线接入技术和网络架构,它的特点是宽带和多功能集成。第四次变革以LTE(长期演进计划)为标志,LTE是2006年以来3GPP启动的最大新技术研发项目,被称作“准4G”技术,包括FDD LTE和TDD LTE两种不同模式,两者主要区别在于FDD为频分双工,而TDD为时分双工。2008年LTE Release8发布以后,各国都加紧研制和部署LTE设备,目前很多国家和地区已经部署了LTE商用网络；我国也于2013年12月颁布了TD-LTE牌照,标志着我国正式进入4G时代。作为全球性的4G标准,LTE具有广阔的市场前景。LTE无线接入网分为物理层、数据链路层和RRC层。物理层处于整个协议的最下层,是无线通信系统的基础,上层数据的正常传输和传输速率等均依赖于物理层。相比3G, LTE显著提高了频谱效率和峰值传输速率等,这主要得益于LTE物理层引入OFDM和MIMO等无线技术,所以研究LTE物理层具有重要意义。本论文主要研究TD-LTE基站物理层下行链路,包括物理层下行链路仿真平台设计、基带处理单元芯片间Serial RapidIO高速总线FPGA侧实现、物理层下行链路DSP实现和典型信令流程验证。主要研究工作和创新点包括： (1)设计并实现TD-LTE物理层下行链路matlab仿真平台。本仿真平台具备以下功能：下行各物理信道和物理信号发送、接收功能,支持各种系统带宽,支持普通CP和扩展CP模式,支持单天线接收单天线发送、发射分集和空分复用MIMO模式,最大发送接收天线数为2X2等。其中发送部分通过Agilent89600VSA验证正常,整个仿真平台发送接收功能测试正常。研究主要算法并对下行各物理信道进行性能仿真和算法改进,目前PCFICH、PDCCH接收误码率测试结果满足LTE规范要求,PBCH、PDSCH接收误码率测试结果比LTE规范差,还需进一步改进。 (2)在FPGA上实现单lane3.125Gbps的Serial RapidIO。由于LTE的多天线、高带宽特性,基带处理单元使用Hyplink和Serial RapidIO来满足其上各芯片之间的高速率数据传输要求。本论文通过研究RapidIO协议标准包括RapidIO物理层、传输层、逻辑层、GTP、链路初始化等,在FPGA上实现了单lane3.125Gbps的Serial RapidIO,经过chipscope等测试工具测试工作正常。 (3)在以TMS320C6670为核心器件的基带处理单元上实现了TD-LTE物理层下行链路并对其进行了验证。研究TMS320C6670DSP芯片并使用其内部FFTC、BCP等协处理器实现TD-LTE物理层下行链路,通过natlab仿真平台和Agilent89600VSA对下行链路DSP实现进行验证,验证结果表明各信道能够正常工作。 (4)学习LTE开机附着流程并基于下行链路进行信令流程调测,由于LTE信令流程正确执行需要各协议层配合完成,本论文提出了数据打桩技术,通过数据打桩技术在仅有物理层下行链路的情况下成功进行了UE开机附着流程前几步的验证。数据打桩技术可以加快项目开发进度,在开发TD-LTE基站设备过程中,我们采用数据打桩技术实际调测开机附着信令流程比传统串行开发调试方法节省了近一半时间。
[Abstract]:With the development of science and technology and human growing demand for mobile communications, has completed the three revolution, is currently fourth times change, compared to 3G, fourth times change the evolution of wireless access technology and network architecture, it is characterized by wide band and multi-function integration. The fourth revolution in LTE (long term evolution) as a symbol, LTE since 2006, 3GPP started the biggest new technology research and development project, known as the "4G" technology, including two different models of FDD LTE and TDD LTE, the major difference between the two is FDD for frequency division duplex, TDD.2008 LTE Release8 for TDD years after the release, all countries are stepping up the development and deployment of LTE equipment, at present a lot of countries and regions have deployed LTE commercial network; China in December 2013 issued TD-LTE licenses, marking China's formal entry into the 4G era. As a global 4G standard, LTE has a broad market prospect of.LTE Wireless access network is divided into physical layer, data link layer and the RRC layer. The underlying physical layer in the whole of the agreement, is the basis of the wireless communication system, the data of normal transmission and transmission rate are dependent on the physical layer. Compared with 3G, LTE significantly improves the spectrum efficiency and peak transmission rate, the main thanks to the introduction of OFDM and MIMO wireless technology to the LTE physical layer, so the research of LTE physical layer has important significance.
This paper mainly studies the TD-LTE base station downlink physical layer downlink simulation platform, including physical layer design, baseband processing unit chip Serial RapidIO high speed bus FPGA side, the physical layer downlink DSP and typical signaling process validation. The main research work and innovation include:
(1) the design and implementation of TD-LTE matlab physical layer downlink simulation platform. This simulation platform has the following functions: send the downlink physical channel and the physical signal receiving function, support a variety of system bandwidth, supports CP and extended CP model, support single antenna receiving single antenna transmission, transmit diversity and spatial multiplexing MIMO model, maximum sending and receiving antenna number is 2X2. The sending section verified by Agilent89600VSA normal, the simulation platform of sending and receiving function test normal. And the main algorithm of the downlink physical channel performance simulation and algorithm improvement, the PCFICH, PDCCH BER test results meet the requirements of LTE, PBCH, PDSCH BER Test Results than the LTE specification is bad, needs to be further improved.
(2) lane3.125Gbps Serial single RapidIO. due to multi antenna LTE in FPGA, high bandwidth characteristics, baseband processing unit using Hyplink and Serial RapidIO to meet the requirements of the between each chip high speed data transmission. Through the study on RapidIO protocol including RapidIO physical layer, transport layer, logic layer, GTP. Link initialization, FPGA to achieve a single lane3.125Gbps Serial RapidIO, after chipscope testing tool to test the normal work.
(3) in the TMS320C6670 as the core component of the baseband processing unit is realized on the TD-LTE physical layer downlink and verified it. Research of TMS320C6670DSP chip and its internal FFTC, BCP coprocessor to achieve the TD-LTE physical layer downlink simulation platform was verified by natlab and Agilent89600VSA on the downlink of DSP implementation, verification results show that the channel be able to work properly.
(4) the learning process and based on the LTE boot attached for downlink signaling flow test, because the LTE signaling process needs correct execution of each layer with the completion of this thesis presents data piling technology, through the data piling technology in physical layer downlink only under the condition of the success of the UE boot attached verification process of the first few steps. The piling technology can accelerate the progress of project development, in the development of TD-LTE base station equipment in the process, we use the data piling technique actually tested the signaling process than the traditional serial attached boot debug method can save nearly half the time.

【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN929.5

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