| 1. | In the second part of this thesis , a method of time synchronization of 2d - ss system in multipath fading channels has been proposed 该算法不需要在数据序列中插入循环前缀,因而减少了系统开销,提高了带宽利用率。 |
| 2. | Based on the above investigation an improved cyclic prefix based channel equalization algorithm is proposed . simulation results show it ' s feasible 对利用循环前缀进行信道估计的方法提出改进,提高了信道估计的性能,仿真结果证明这种改进是有效的。 |
| 3. | ( 2 ) estimation and equalization of multipath fading wireless channel which was modeled as complex - taps fir have been done using cyclic prefix under i / q modulation 采用复抽头系数的fir滤波器来对无线信道进行建模,并用循环前缀作为训练序列对信道进行估计和均衡。 |
| 4. | A subspace - based blind channel estimator has been developed for space time coding orthogonal frequency division multiplexing ( stc - ofdm ) system with two transmit antennas and two receive antennas 摘要针对使用2个发射天线和2个接收天线并且采用循环前缀的空时编码正交频分复用系统( stc - ofdm ) ,提出了一种信道盲估计算法,并给出信道可被辨识的条件。 |
| 5. | In frequency synchronization , we mainly discussed two algorithms of fine frequency synchronizations , and compared them with each other . we adopted the algorithm based on cyclic prefix as the fine frequency synchronization for the system 频率同步方面主要提出了两种精频偏估计算法,并对两种算法进行比较,采用了基于循环前缀的精频偏估计算法作为系统精频偏算法。 |
| 6. | With qpsk modulation method employed in our ofdm system , there are several important parameters relating to bandwidth efficiency should be consider carefully . they are the number of subcarrier , the length of cycle prefix and the parameters of pulse shaping filer 结合qpsk调制,文中讨论了建立这样一个高带宽效率的ofdm传输系统所需要着重考虑的几个参数:子载波数目、循环前缀长度和成形滤波器的参数。 |
| 7. | Then , the system model and its simulation flow chart in matlab are introduced for mc - cdma system . and some technologies of mc - cdma and their functions in mc - cdma system are emphasized , such as frequency spread of data in frequency domain , ifft and cyclic prefix , and so on 然后在给出了mc - cdma系统模型和matlab仿真流程基础上,重点讨论了mc - cdma系统中的主要应用技术及其在整个系统中的作用,例如数据的频域扩频、 ifft变换和循环前缀等。 |
| 8. | The blind synchronization method based on cyclostationarity is firstly analyzed in the downlink . simulations of the method are carried out under different channel conditions . the performances of the method are analyzed , and then compared with the blind method based on the cyclic prefix of ofdm symbols , thus the validity of the method is proved 本文首先在下行链路中分析了基于ofdm信号的循环平稳特性的盲同步信息估计算法,并在多种信道条件下进行了计算机仿真,对基于ofdm信号循环平稳特性的估计器的性能进行了分析,并与基于ofdm信号循环前缀的ml算法的估计性能进行了比较,从而证明了提出算法的有效性。 |
| 9. | This paper concentrates on the orthogonal frequency division multiplexing ( ofdm ) technique and some techniques to resist multipath fading . eliminate isi through use of a cyclic prefix . diversity techniques . using adequate ofdm combined with channel coding ( cofdm ) can enhance the ability to lower the effect of multipath fading 本文研究了ofdm的基本原理及抗多径衰落的一些措施,如加循环前缀,利用多径进行分集接收,将ofdm与信道编码及交织结合起来,频域均衡。 |
| 10. | According to wireless and mobile communication system ' s background , this thesis study on estimation of time - varying dispersive channel from four respects : ( 1 ) aid of pilots , ( 2 ) cyclic prefix ( cp ) , ( 3 ) blind method , and ( 4 ) ofdm system with multiple transmitting antenna , in which the typical ways is decision - feedback algorithm and self - adaptive block algorithm 本文以无线和移动通信系统为背景,从四个方面对时变色散信道下的ofdm系统的信道估计和均衡问题进行了研究。第一是基于导频符号的信道估计方法,第二是基于循环前缀的信道估计方法,第三是信道的盲估计方法,第四是基于多天线ofdm系统的信道估计和均衡方法的研究。 |