基于分段混合调制的导频辅助块传输技术研究

张磊; 焦现军; 陈江; 项海格

doi:10.3724/SP.J.1146.2006.01538

基于分段混合调制的导频辅助块传输技术研究

doi: 10.3724/SP.J.1146.2006.01538

基金项目:

国家自然科学基金(60302006, 60462002)资助课题

计量
- 文章访问数: 3309
- HTML全文浏览量: 73
- PDF下载量: 795
- 被引次数: 0
出版历程
- 收稿日期: 2006-10-10
- 修回日期: 2007-03-16
- 刊出日期: 2008-04-19

A Novel Hybrid Modulation Scheme for Pilot-assisted Block Transmission Technology

摘要

摘要: 在导频与数据时分复接的块传输系统中，无保护间隔系统具有最佳的数据传输效率，但工作在多径信道下时，该系统接收信号中导频和数据边缘混叠，接收机需要额外的干扰消除操作以精确分离二者。实际干扰消除算法都会存在一定误差，这种误差会降低信道估计算法的精度，进一步影响整个数据块的解调及解码，最后导致系统误码性能下降。该文提出一种分段混合调制方式：数据块中，可能与导频发生混叠的前后两端数据符号采用低阶调制；而中部依然采用高阶调制。仿真结果表明，在典型大延时多径信道下，分段混合调制系统误码性能明显优于传统无保护间隔的时分导频辅助块传输系统。
- 无线通信; 导频辅助块传输系统; 分段混合调制
Abstract: When PABT (Pilot-Assisted Block Transmission) signal is transmitted over severe multipath channels, consecutive pilot block and data block may partially overlap each other. If no guard interval is inserted between them, a process to cancel the mutual interference is usually adopted in the receiver. But this process, as well as channel equalization, may suffer severe performance degradation when channel estimation is not so reliable. A hybrid modulation scheme is proposed in this paper, in which the overlapped part in data block is modulated using lower order constellation, while the other part keeps using higher order constellation. Its advantage in BER performance and robustness over conventional PABT schemes is demonstrated with simulation in some multipath channels with large delay spread.

HTML全文

参考文献(1)

Tong Lang, Sadler B M, and Dong Min. Pilot-assistedwireless transmissions: general model, design criteria, andsignal processing[J].IEEE Signal Processing Magazine.2004,21(11):12-25[2]Cavers J K. An analysis of pilot symbol assisted modulationfor Rayleigh fading channels[J].IEEE Trans. on Veh. Technol.1991, 40(4):686-693[3]Group Speciale Mobile (GSM) Recommendations, GSMSeries 01-12, 1990.[4]Physical channels and mapping of transport channels ontophysical channels (FDD), WCDMA, 2001.Physical Layer Standard for CDMA2000 Spread SpectrumSystems, CDMA2000, 2001.[5]ETSI. Digital Video Broadcasting (DVB); Framing structure,channel coding and modulation for digital terrestrialtelevision. European Telecommunication Standard EN300744,2004.[6]Zheng Z W, Yang Z X, Pan C Y, and Zhu Y S. Novelsynchronization for TDS-OFDM-based digital televisionterrestrial broadcast systems[J].IEEE Trans. on Broadcast.2004, 50(2):148-153[7]IEEE. Part11: Wireless LAN Medium Access Control (MAC)and Physical Layer (PHY) Specifications: High SpeedPhysical Layer in the GHz Band. Std 802.11a/D7.0-1999.[8]IEEE. Part 11: Wireless LAN Medium Access Control (MAC)and Physical Layer (PHY) specifications Amendment 4:Further Higher Data Rate Extension in the 2.4 GHz Band.IEEE Std 802.11g-2003.[9]ETSI. Broadband Radio Access Networks (BRAN);HIPERLAN type 2 technical specification; Physical (PHY)layer. V 1.3.1, ETSI TS 101475, 2001.[10]IEEE. Part 16: Air Interface for Fixed Broadband WirelessAccess Systems. IEEE Std 802.16a-2004.[11]焦现军. 导频辅助的块传输技术. [博士论文], 北京大学, 2006.Jiao Xianjun. Pilot assisted block transmission. [Dissertation],Peking University, 2006.[12]Wang Z and Giannakis G B. Wireless multicarriercommunications: where fourier meets Shannon[J].IEEE SignalProcessing Magazine.2000, 17(3):29-48[13]Muquet B and Zhengdao W, et al.. Cyclic prefixing or zeropadding for wireless multicarrier transmissions[J].IEEE Trans.on Communications.2002, 50(12):2136-2148[14]焦现军, 张磊, 项海格. 采用PN 导频的但在频域均衡系统.北京大学学报, 2007, 43(1): 103-108.Jiao Xianjun, Zhang Lei, and Xiang Haige. PN based channelestimation in SC-FDE system. Acta Scientiarum NaturaliumUniversitais Pekinensis, 2007, 43(1): 103-108.[15]Song Bowei, Gui Lin, and Guan Yunfeng, et al.. On channelestimation and equalization in TDS-OFDM based terrestrialHDTV broadcasting system. IEEE Trans. on ConsumerElectronics, 2005, 51(3): 790-797.[16]焦现军, 张磊, 项海格. 采用频域导频的块传输[J].电子与信息学报.2007, 29(11):2616-2619浏览[17]Wang Jun and Yang Zhixing, et al.. Iterative paddingsubtraction of the PN sequence for the TDS-OFDM overbroadcast channels[J].IEEE Trans. on Consumer Electronics.2005, 51(4):1148-1152[18]Chen Rongrong, Koetter R, Madhow U, and Agrawal D.Joint noncoherent demodulation and decoding for the blockfading channel: A practical framework for approachingshannon capacity[J].IEEE Trans. on Communication.2003,51(10):1676-1689

施引文献

资源附件(0)

访问统计