查询词典 estimation

Thirdly, the maximum-likelihood CFO estimation algorithms based on null-subcarrier are investigated, and it is shown that the maximum-likelihood CFO estimation algorithm based on equispaced null-subcarriers is equivalent to the CFO estimation algorithm utilizing the correlation of repeated training sequences.

提出了两种基于时域相关峰值检测的同步估计改进算法：1）采用一个OFDM符号做为训练序列，在接收端进行差分相关以解决时间度量函数中出现的平台效应。

However, blind channel estimation is a very complex, very fargoing research topic. Because of the author's limit ability and time, only the simple subspace channel estimation method is studied. In the third part of this dissertation, the subspace channel estimation method in MIMO-OFDM systems is investigated.

信道盲估计技术因为仅仅根据接收到的序列来估计信道而特别有吸引力，盲估计方法大大提高了通信系统的吞吐量，因此，MIMO-OFDM系统中的盲信道估计技术成为一个研究热点。

Compared with the common LS channel estimation, the iterative algorithm of joint LS channel estimation and signal detection can highly promote the estimation accuracy. Moreover, the lowpass filtering in time domain reduces AWGN and intercarrier interference significantly. It enables OFDM systems to work well in mobile communications.

与一般的LS信道估计相比，基于OFDM的LS信道估计与信号检测的联合迭代算法可较大地提高估计的精度，而且通过时域低通滤波可有效地抑制AWGN和ICI的影响，可使OFDM系统在移动条件下较好地工作。

Studies the high precision estimation methods of echo frequency, proposes a simplified TLS-ESPRIT method for frequency estimation based on uniform sampling data. For moving platform, such as torpedo, proposes a time fusion algorithm for target status estimation based on multicycle data of single sensor.

c。深入研究了回波信号的高精度频率估计技术，提出了一种基于均匀采样数据的TLS-ESPRIT频率估计算法；针对运动平台，提出了一种单传感器多测量周期目标状态估计的时间融合算法；以炸点预测为例构造了相应的状态模型及算法，计算机仿真验证了融合算法的有效性。

The paper discusses moment estimation of parameters on Copulas with two kind of methods-moment estimation and approximate moment estimation, and compares two methods by simulation.

本文研究了Gumbel Copula函数的参数佑计，提出了矩估计和近似矩估计两种方法，分别得到了未知参数的估计结果，并通过模拟研究对这两种方法进行了比较，结果显示矩估计方法更为合理。

To demodulate the OFDM signals accurately, channel estimation algorithms are adopted. This paper examines the slow-fading estimation algorithms based on block pilot arrangement: LS and LMMSE algorithms, as well as the fast-fading channel estimation algorithms based on comb-type pilot arrangement: linear and transform domain interpolation algorithms.

本文分析了导频分布的两种方案：1块状导频分布，对基于块状导频分布方案的慢衰落信道估计算法：最小平方和线性最小均方误差算法进行了计算机仿真，比较了二者的估计性能，以及各自的优缺点；2梳状导频分布，对基于这种分布方案的快衰落信道估计算法进行了研究，对两类经典算法：线性插值法和基于变换域的插值法分别进行了理论分析和计算机仿真。

In addition, because motion vectors must be estimated in the process of region's motion parameters estimation, this paper discussed the theory and general methods of two-dimensional motion estimation and proposes a fast motion estimation algorithm based on the prediction of neighbour block's motion vector.

此外，由于在区域的运动参数估计过程中涉及到对运动矢量的估计，因此本文还讨论了二维运动矢量估计的原理和一般方法，并提出了一种基于邻域子块的运动矢量预测的快速运动估计算法。

In this paper, a Minimum Mean Square Error based joint multi-cell channel estimation algorithm is proposed. By including the strong interfering users of adjacent cells into the channel estimation matrix, the noise power is significantly reduced which guarantees more precise channel estimation.

该文提出基于最小均方误差准则的联合多小区信道估计算法，由于改变了信道估计矩阵的结构，将邻小区强干扰用户也作为可以检测的用户信号来处理，降低了信道估计中噪声功率。

The investigations included the following:（1） estimation of sea ice distribution by ship-based observations between Middle Weddell Sea and Prydz Bay;（2） estimation of sea ice distribution by aerial photography in the Prydz Bay;（3） direct measurements of fast ice thickness and snow cover, as well as ice core sampling in Nella Fjord;（4） estimation of melting sea ice patterns near the ZhongShan Station; and （5） observation of sea ice early freezing near the ZhongShan Station.

包括：（1）基于走航观测的威德尔海至普利茨湾之间海冰分布研究；（2）基于航空拍摄的普利茨湾海冰分布研究；（3）纳拉海峡固定冰和上浮雪厚度钻孔测量以及冰心钻取；（4）中山站附近融化冰的分布研究以及（5）中山站附近海冰早期冻结过程观测研究。

The algorithm firstly selects effective area,the extent of wet and dry,position offset as estimation factor,considering all estimation factors in order to obtain the total quality point,secondly the ultimate estimation result is obtained based on above,finally isolated block is removed by calculating the area of the remaining fingerprint.

该算法首先选取指纹图像的有效面积、干湿程度、位置偏移量作为评价因子，然后综合考虑各种评价因子求取总的质量分得到最终的评价结果；最后通过计算面积割除孤立的残留指纹。

Objective: To study the effect of polycythemia on blood oxygen saturation.

裴蕾目的：观察RBC剧增而引起的高粘血症对血氧饱和度的影响。

Based on SIMPLER algorithm in the curvilinear body-fitted coordinates, the calculations were performed for Pr=0.7, Re=10~1000 on non-orthogonal non-staggered grids which are generated by elliptic equation systems.

采用曲线坐标系下压力与速度耦合的SIMPLER算法，数值研究了周期性渐扩渐缩波纹通道内脉动流动与换热情况，流动Re数的范围为10~1000，Pr数为0.7。