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Doppler-robust high-spectrum-efficiency VCM-OFDM scheme for low Earth orbit satellites broadband data transmission 期刊论文  OAI收割
IET COMMUNICATIONS, 2018, 卷号: 12, 期号: 1, 页码: 35-43
作者:  
Li, Jionghui;  Xiong, Weiming;  Sun, Geng;  Wang, Zhugang;  Huang, Yonghui
  |  收藏  |  浏览/下载:76/0  |  提交时间:2018/03/02
OFDM baseband modulation technology based on VHDL (EI CONFERENCE) 会议论文  OAI收割
2010 IEEE International Conference on Advanced Computer Control, ICACC 2010, March 27, 2010 - March 29, 2010, 445 Hoes Lane - P.O.Box 1331, Piscataway, NJ 08855-1331, United States
Lin L.; Qiao Y.-F.; Su W.-X.
收藏  |  浏览/下载:16/0  |  提交时间:2013/03/25
In order to improve the transmission velocity in mulitipath fading wireless channel  two main advantages are obtained via discussing spectrum utilization ratio of OFDM. Then  the high speed OFDM technology receives increasing attentions in mobile communication. Modulation programs are designed with VHDL based on the principle of OFDM in the paper. First  from the results of VHDL simulation  after OFDM fundamental is introduced  the realization of baseband operations  such as interleaver  subcarrier modulation  IFFT and adding CP  are presented. Finally  implemented programs are validated on the actual implement system. Experimental results indicate that setup time corresponding to transmission velocity is only 71.05s and steady time is approximately 6 times as setup time  that is  not only achieving the high speed transmission  but also supplying adequate modulation time. 2010 IEEE.  
Estimation algorithm of mobile OFDM CFOs based on step-size (EI CONFERENCE) 会议论文  OAI收割
2009 International Conference on Information Engineering and Computer Science, ICIECS 2009, December 19, 2009 - December 20, 2009, Wuhan, China
Lin L.; Qiao Y.-F.; Su W.-X.
收藏  |  浏览/下载:27/0  |  提交时间:2013/03/25
In order to maintain orthogonality among subcarriers for mobile OFDM  a CFOs step-size estimation model is established to avoid severe performance degradation caused by ICI  and algorithmic stability  step-size parameter  the error of CFOs estimate and etc are investigated. First  after an averaging window algorithm is introduced  the mathematic model of step-size estimation algorithm is obtained through step-size parameter and time-varying CFOs. Then  based on the results of MATLAB simulation  the determination of step-size parameter  the advantages of step-size algorithm and precision are discussed. Finally  time sequence plots of added CP  interleaver and subcarrier modulation with VHDL are presented. Experimental results indicate that the maximum of CFOs errors is 0.00987 in 3 variance interval  when mobile velocity is 400 km/h  according with verdicted principle that in order for the ICI effects to be negligible  the error of CFOs estimation must be accurate within 1-2% of the subcarrier spacing  and programs can correctly implement on circuit board. 2009 IEEE.