LTE上行物理层接收机算法设计
摘要
为了提高第3代移动通信技术在无线接入领域的竞争力,3GPP提出了第3代移动通信的长期演进计划(Long Term Evolution,简称LTE)。LTE旨在提高数据速率,降低系统时延,增大系统容量和覆盖范围,同时降低运营成本。LTE是国际化标准组织3GPP开展的重要项目,因而对LTE技术的研究很有意义,然而接收机算法直接影响链路的性能,特别是LTE上行接收机算法,所以对LTE上行链路物理层接收机算法研究意义重大。
本文主要针对LTE上行物理层链路接收机算法进行研究。
首先,介绍了LTE的研究背景、研究意义、研究内容及研究目的。
其次,介绍了LTE物理层上行链路的基本结构流程及关键技术,基本内容包括CRC校验、码块分割、速率匹配、Turbo编码、调制等。其关键技术主要是SC-FDMA和虚拟MIMO技术。
之后,根据LTE上行发射侧关键技术的特点以及编码调制方式,设计接收机算法,这些算法主要包括信道估计(LS信道估计、理想信道估计、LMMSE信道估计、时域相关信道估计),频偏估计以及解虚拟MIMO(ZF、LMMSE、ML)的原理和算法实现。
最后,对链路性能进行仿真验证,包括:(1)在相同的仿真条件下,不同信道估计对性能的影响,主要是理想信道估计,ML(最大似然)信道估计和时域相关信道估计;(2)接收分集中,2天线和4天线的性能对比;(3)单发射天线与虚拟MIMO的性能对比;(4)频偏估计对性能的影响。
In order to maintain the future competitiveness of the Third Gerneration (3G) in ten-year, the Third Generation Partnership Project (3GPP) organization passed the 3G long term evolution (LTE) scheme, the main purposes that LTE concerned were to increase data rates, reduce latency, improve system capacity and coverage and reduce operator cost. LTE is an important project which is processed by international standard organization. For receiver algorithm has influence on the performance of the link, so the study of LTE Uplink receiver algorithm became very valuable.
This article focused on studies of uplink receiver algorithm.
First, it listed the background, the significance, the main purpose and content of LTE physical layer uplink receiver algorithm.
In the following part, there are the main structure of LTE uplink and some main technologies, including adding CRC, code segment, rate matching, turbo coding, modulation and so on. The pivotal technologies are SC-FDMA and virtual MIMO.
Thirdly, according to the characters of transistor, we designed the receiver algorithm, including channel estimation (LS, ideal channel estimation, time-domain correlative channel estimation), frequency offset estimation and demodulation for MIMO.
At last, we simulated the performance in different conditions. (1) the influence on link performance in different channel estimation. (2) The influence rasied by 2 and 4 receiver antenna. (3) The performance played by single sending antenna and virtual MIMO. (4) The performance at different frequency offset.
本文主要针对LTE上行物理层链路接收机算法进行研究。
首先,介绍了LTE的研究背景、研究意义、研究内容及研究目的。
其次,介绍了LTE物理层上行链路的基本结构流程及关键技术,基本内容包括CRC校验、码块分割、速率匹配、Turbo编码、调制等。其关键技术主要是SC-FDMA和虚拟MIMO技术。
之后,根据LTE上行发射侧关键技术的特点以及编码调制方式,设计接收机算法,这些算法主要包括信道估计(LS信道估计、理想信道估计、LMMSE信道估计、时域相关信道估计),频偏估计以及解虚拟MIMO(ZF、LMMSE、ML)的原理和算法实现。
最后,对链路性能进行仿真验证,包括:(1)在相同的仿真条件下,不同信道估计对性能的影响,主要是理想信道估计,ML(最大似然)信道估计和时域相关信道估计;(2)接收分集中,2天线和4天线的性能对比;(3)单发射天线与虚拟MIMO的性能对比;(4)频偏估计对性能的影响。
In order to maintain the future competitiveness of the Third Gerneration (3G) in ten-year, the Third Generation Partnership Project (3GPP) organization passed the 3G long term evolution (LTE) scheme, the main purposes that LTE concerned were to increase data rates, reduce latency, improve system capacity and coverage and reduce operator cost. LTE is an important project which is processed by international standard organization. For receiver algorithm has influence on the performance of the link, so the study of LTE Uplink receiver algorithm became very valuable.
This article focused on studies of uplink receiver algorithm.
First, it listed the background, the significance, the main purpose and content of LTE physical layer uplink receiver algorithm.
In the following part, there are the main structure of LTE uplink and some main technologies, including adding CRC, code segment, rate matching, turbo coding, modulation and so on. The pivotal technologies are SC-FDMA and virtual MIMO.
Thirdly, according to the characters of transistor, we designed the receiver algorithm, including channel estimation (LS, ideal channel estimation, time-domain correlative channel estimation), frequency offset estimation and demodulation for MIMO.
At last, we simulated the performance in different conditions. (1) the influence on link performance in different channel estimation. (2) The influence rasied by 2 and 4 receiver antenna. (3) The performance played by single sending antenna and virtual MIMO. (4) The performance at different frequency offset.
引文
1王维. LTE上行接收技术的研究.北京邮电大学硕士学位论文. 2007:21~22
2 Suk Yu Hui, Kai Hau Yeung. Challenges in migration to 4G mobile systems. IEEE Comm. Mag, 2003,41(12):54~59
3 Erik Dahlman, Stefan Parkvall, Johan Skold. HSPA and LTE for Mobile Broadband
4 Evolved Universal Terrestrial Radio Access Multiplexing and channel coding. 3rd Generation Partnership Project. 2008,9
5 Evolved Universal Terrestrial Radio Access Physical Channels and Modulation. 3rd Generation Partnership Project. 2008,8
6 Physical layer aspects for evolved UTRA. 3rd Generation Partnership Project TR 25.814, 2006
7王新梅,肖国镇.纠错码原理与方法.电子工业出版社,1996,7
8 64QAM for HSDPA– Indoor Performance with/without MIMO. R1-063500. 2006
9 Multiple-Input Multiple Output in UTRA. TR25.876. 2007
10 Sub-band BW for Frequency Selective Scheduling and CQI Feedback. Samsung. 2006
11胡耀,李方伟. LTE及关键技术介绍.广东通信技术. 2006,5:9~12
12黄韬,袁超伟,杨睿哲,刘鸣. MIMO相关技术与应用.第一版,北京机械工业出版社, 2007:16~20
13罗涛,乐光新.多天线无线通信原理与应用.第一版,北京邮电大学出版社, 2005,11:10~16
14 L. E. Telator. Capacity of multi-antenna Gaussian channel. AT&TBell Labs, Teeh. Memo, 1995:1~28
15 Sergey Loyka. Channel capacity of MIMO architecture using the exponential correlation matrix. IEEE Communication Letters,2001,5(9):369~371
16宋铁成.下一代移动通信系统中的OFDM技术.移动通信,2001
17汪裕民. OFDM关键技术与应用.北京,机械工业出版社,2007:20~30
18 JianHua Zhang, ChenHuang, Guangyiliu. Comparison of the Link Levelperformance between OFDMA and SC-FDMA. IEEE, 2006
19孙山林,侯春萍. MIMO一OFDM系统的信道估计算法.信息技术2006.1
20韩冰,高西奇. OFDM系统的一种新的信道参数估计方法.应用科学学报, 2004
21徐娇月.基于导频的OFDM信道估计的研究.大连海事大学硕士论文. 2007: 9~13
22 Yao tao, Qiao Song, Yu Peng. Research on An lterative Alogrithm of Ls channel Estimation in MIMO-OFDM systems. IEEE,6th CAS symp on
23丁靖,张海滨,罗汉问. OFDM中的信道估计方法.通信技术,2002,12
24张胜利,朱近康,张力力. OFDM系统中新的信道估计方法.电子与信息学报,2007,29(1),157~160
25张晓瀛,韩湘.基于导频的OFDM信道估计.现代电子技术, 2003,21
26刘冬生.基于CAZAC码的LTE上行导频结构的研究.西安电子科技大学硕士论文. 2007:20~25
27 Die Hu, Luxi Yang and Yuhui Shi. Optimal Pilot Sequence Design for Channel Estimation in MIMO OFDM Systems. IEEE COMMUNICATIONS LETTERS, 2006,10(1):1~3
28葛启宏,陆建华.基于二维DFT的导频模式OFDM信道估计算法.清华大学学报,2004,44
29 P. H. Moose. A technique for orthogonal frequeney division multiplexing frequency Offset correction. IEEE Trans Conunun. 1994,42(10):2908~2914
30 M. Morelli and U. Mengali. An Improved frequency offset estimator for OFDM Application. IEEE Conunun.Lett. 1999,3(3):75~77
31 S. M. Kay.统计信号处理基础-估计与检测理论.电子工业出版社,2003
32张贤达.矩阵分析与应用.清华大学出版社,2004
33姜奕. MIMO信道下VBLAST接收机关键技术研究. 2006,2
34宋晓晖.基于MIMO OFDM系统的信号检测算法分析.兰州大学硕士论文. 2008:27~29
35 G..Ungerboeck. A daptive maximum-likelihood receiver for carrier modulated data-transmission system. IEEE Trans. Commun. vol, (22):624~636
36 A. Klein, G. K. Kaeh and P. W. Baier. Zero forcing and minimum mean-square-error equalization for multiuser detection in code-divisionmultiple-access channels. IEEE Trans. Vehic.vol, (45):276~287
37马俊. B3G中的MIMO检测算法与实现技术研究.电子科技大学硕士论文. 2007:42~45
38贺中堂,张力军,陈自力. MIMO OFDM系统基于QR分解的信号检测算法.计算机工程与应用. 2006,14
39 Zhiqiang Liu, YanXin, GeorgiosB.Giannakis. Space-Time-Frequency coded OFDM Over Frequeney-Selcetive Fading Channels. IEEE Trans. On Signal Proeessing. 2002,50(10):2465~2476
40 DamenM.O, Abed-Meraim K. Iterative QR detection for Blast Wireless Personal Communications. 2001,19(3):179~192
41 Simulation Methodology for EUTRA UL: IFDMA and DFT-Spread-OFDMA. Motorola. R1-051335. 2005:7~11
42 Evolved Universal Terrestrial Radio Access, Base Station radio transmission and reception. 3GPP TS 36.104. 2008,9
43 Evolved Universal Terrestrial Radio Access User Equipment radio transmission and reception. 3GPP TS 36.101. 2008,9
44 T. Pollet, M. vanBladel and M. Moeneclaey. BER sensitivity of OFDM systems to carrier frequency offset and Wiener phase noise. IEEE Trans. Commun. 1993, (43):191~193
45 Eriesson. R1-061001. LTE Channel Models and Link simulations. 2006,5
46 Spatial channel model for Multiple Input Multiple Output(MIMO) simulation. 3GPP TR25.996. 2007
2 Suk Yu Hui, Kai Hau Yeung. Challenges in migration to 4G mobile systems. IEEE Comm. Mag, 2003,41(12):54~59
3 Erik Dahlman, Stefan Parkvall, Johan Skold. HSPA and LTE for Mobile Broadband
4 Evolved Universal Terrestrial Radio Access Multiplexing and channel coding. 3rd Generation Partnership Project. 2008,9
5 Evolved Universal Terrestrial Radio Access Physical Channels and Modulation. 3rd Generation Partnership Project. 2008,8
6 Physical layer aspects for evolved UTRA. 3rd Generation Partnership Project TR 25.814, 2006
7王新梅,肖国镇.纠错码原理与方法.电子工业出版社,1996,7
8 64QAM for HSDPA– Indoor Performance with/without MIMO. R1-063500. 2006
9 Multiple-Input Multiple Output in UTRA. TR25.876. 2007
10 Sub-band BW for Frequency Selective Scheduling and CQI Feedback. Samsung. 2006
11胡耀,李方伟. LTE及关键技术介绍.广东通信技术. 2006,5:9~12
12黄韬,袁超伟,杨睿哲,刘鸣. MIMO相关技术与应用.第一版,北京机械工业出版社, 2007:16~20
13罗涛,乐光新.多天线无线通信原理与应用.第一版,北京邮电大学出版社, 2005,11:10~16
14 L. E. Telator. Capacity of multi-antenna Gaussian channel. AT&TBell Labs, Teeh. Memo, 1995:1~28
15 Sergey Loyka. Channel capacity of MIMO architecture using the exponential correlation matrix. IEEE Communication Letters,2001,5(9):369~371
16宋铁成.下一代移动通信系统中的OFDM技术.移动通信,2001
17汪裕民. OFDM关键技术与应用.北京,机械工业出版社,2007:20~30
18 JianHua Zhang, ChenHuang, Guangyiliu. Comparison of the Link Levelperformance between OFDMA and SC-FDMA. IEEE, 2006
19孙山林,侯春萍. MIMO一OFDM系统的信道估计算法.信息技术2006.1
20韩冰,高西奇. OFDM系统的一种新的信道参数估计方法.应用科学学报, 2004
21徐娇月.基于导频的OFDM信道估计的研究.大连海事大学硕士论文. 2007: 9~13
22 Yao tao, Qiao Song, Yu Peng. Research on An lterative Alogrithm of Ls channel Estimation in MIMO-OFDM systems. IEEE,6th CAS symp on
23丁靖,张海滨,罗汉问. OFDM中的信道估计方法.通信技术,2002,12
24张胜利,朱近康,张力力. OFDM系统中新的信道估计方法.电子与信息学报,2007,29(1),157~160
25张晓瀛,韩湘.基于导频的OFDM信道估计.现代电子技术, 2003,21
26刘冬生.基于CAZAC码的LTE上行导频结构的研究.西安电子科技大学硕士论文. 2007:20~25
27 Die Hu, Luxi Yang and Yuhui Shi. Optimal Pilot Sequence Design for Channel Estimation in MIMO OFDM Systems. IEEE COMMUNICATIONS LETTERS, 2006,10(1):1~3
28葛启宏,陆建华.基于二维DFT的导频模式OFDM信道估计算法.清华大学学报,2004,44
29 P. H. Moose. A technique for orthogonal frequeney division multiplexing frequency Offset correction. IEEE Trans Conunun. 1994,42(10):2908~2914
30 M. Morelli and U. Mengali. An Improved frequency offset estimator for OFDM Application. IEEE Conunun.Lett. 1999,3(3):75~77
31 S. M. Kay.统计信号处理基础-估计与检测理论.电子工业出版社,2003
32张贤达.矩阵分析与应用.清华大学出版社,2004
33姜奕. MIMO信道下VBLAST接收机关键技术研究. 2006,2
34宋晓晖.基于MIMO OFDM系统的信号检测算法分析.兰州大学硕士论文. 2008:27~29
35 G..Ungerboeck. A daptive maximum-likelihood receiver for carrier modulated data-transmission system. IEEE Trans. Commun. vol, (22):624~636
36 A. Klein, G. K. Kaeh and P. W. Baier. Zero forcing and minimum mean-square-error equalization for multiuser detection in code-divisionmultiple-access channels. IEEE Trans. Vehic.vol, (45):276~287
37马俊. B3G中的MIMO检测算法与实现技术研究.电子科技大学硕士论文. 2007:42~45
38贺中堂,张力军,陈自力. MIMO OFDM系统基于QR分解的信号检测算法.计算机工程与应用. 2006,14
39 Zhiqiang Liu, YanXin, GeorgiosB.Giannakis. Space-Time-Frequency coded OFDM Over Frequeney-Selcetive Fading Channels. IEEE Trans. On Signal Proeessing. 2002,50(10):2465~2476
40 DamenM.O, Abed-Meraim K. Iterative QR detection for Blast Wireless Personal Communications. 2001,19(3):179~192
41 Simulation Methodology for EUTRA UL: IFDMA and DFT-Spread-OFDMA. Motorola. R1-051335. 2005:7~11
42 Evolved Universal Terrestrial Radio Access, Base Station radio transmission and reception. 3GPP TS 36.104. 2008,9
43 Evolved Universal Terrestrial Radio Access User Equipment radio transmission and reception. 3GPP TS 36.101. 2008,9
44 T. Pollet, M. vanBladel and M. Moeneclaey. BER sensitivity of OFDM systems to carrier frequency offset and Wiener phase noise. IEEE Trans. Commun. 1993, (43):191~193
45 Eriesson. R1-061001. LTE Channel Models and Link simulations. 2006,5
46 Spatial channel model for Multiple Input Multiple Output(MIMO) simulation. 3GPP TR25.996. 2007