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The paper investigates both block-type pilot linear minimum mean square error algorithm and IEEE802.16 OFDM channel estimation analysis. Simulation results confirm the block-type pilot structure is more suitable for IEEE802.16 system. An optimal pilot setting algorithm, based on space frequency domain, is explored and the pilot chart is presented. The proposed algorithm finds its application in MIMO-OFDM. Simulation results show the algorithm presents a good approximation to the perfect channel state information curve, with about 2dB difference in SNR. The simulation results also demonstrate the algorithm achieves fairly high stability in the environment of fast fading, performance of the proposed algorithm is better that of pilot training channel estimation.3. Taking into account the characteristics of IEEE802.16 OFDM system, OFDM system simulation platform is constructed in Matlab, exploiting simulink as a tool. OFDM modulation and demodulation simulation system are configured on LabVIEW platform. All the system signal processing is simulated, including defining system parameters, designing modulation model, and verifying all the proposed algorithms under different environments, such as white Gaussian noise, multi-path fading, with or without guard interval etc. Bit error performance is evaluated. The research provides valid theoretical basis for practical OFDM system performance evaluation.4. Taking advantage of software radio, the paper designs a hardware platform with both 256-IFFT/FFT and 512-IFFT/FFT OFDM schemes co-existing in one platform. You can predetermine one from the two schemes to carry out almost the same model function with different system performance and parameter setting.5. Referring to IEEE802.16 standard, the paper proposes a design method for generating signals and frames suitable for laboratory investigations implemented in laboratory environment.6. Based on 6701evm digital evaluation card, combined with analogy front-end, the paper designs a DSP software model to deal with baseband signal processing. An overall OFDM scheme, with modulation and demodulation function, is accomplished.

讨论分析了MIMO-OFDM中一种基于空频域的最优导频设置算法，给出了导频图案，通过仿真实验表明，该算法与理想的信道状态信息曲线非常接近，信噪比差距约在2dB左右，并且在快衰落条件下具有较好的稳定性，其性能要优于基于前导训练的信道估计方法。3、根据IEEE802.16OFDM系统特点，论文分别在Matlab中应用Simulink工具构建OFDM系统仿真平台、在LabVIEW平台上实现了OFDM调制解调仿真系统，模拟了整个系统的信号流程，进行了OFDM仿真系统参数的选择和调制模块的仿真设计、论证各算法性能，并根据各种不同的条件：例如高斯噪声、多径衰落、有无保护间隔等，对系统的误码特性进行了评估，为正确评价实际OFDM系统的性能提供了有效的理论依据。4、论文以软件无线电思想作为指导，提出了以256点IFFT／FFT为核心和以512点IFFT／FFT为核心的两种OFDM算法模式并存于同一个硬件平台、且可预选的方案，它们在参数选取和性能指标上有所差异，均实现了相似的模块和功能。5、论文参考IEEE 802.16无线网络标准的参数设置，针对本设计系统的应用环境和系统硬件的性能速率，提出了一种应用于实验室环境的信号结构、帧格式等参数设计。6、论文基于TI公司的6701evm数字评估板卡，结合模拟前端搭建数字中频平台，设计了基带处理的DSP软件模块并进行系统调试，基本实现了一套完整的OFDM调制解调方案。

Further, a vapor discharge opening and a vapor discharge valve mechanism are provided in that part of the pump channel which is between the air discharge opening and an inlet section of the pump channel. The vapor discharge valve mechanism is closed in the start of the pump, preventing negative pressure at a fuel suction opening from being reduced, and the mechanism is opened in the start of fuel pressurization, discharging fuel containing vapor to the outside of the pump channel.

另外，在上述空气排出口和泵流路的入口部之间的泵流路上设置蒸汽排出口，此外设置蒸汽排出阀机构，其在燃料泵启动时闭阀而防止燃料吸入口的负压降低，如果燃料加压开始则开阀，从而将含有蒸汽的燃料向泵流路的外部排出。

The evolvement of grain orientation for the sheets during this processing and the influence of channel clearance on it were investigated.The results indicate that the shear stress and compression stress are put on the sheet at the channel corner during equal channel angular rolling.And the shearing deformation on...

结果表明，在等径角轧制过程中，板材在模具转角处受到剪应力和压应力的作用；随通道间隙的增加，板材的变形由剪切变形演变为剪切+弯曲变形，甚至弯曲变形；由于剪应力的作用，AZ31镁合金板材的晶粒取向由普通轧制所形成的基面取向转变为等径角轧制后的非基面取向，随着剪切变形量的减小，基面沿轧制方向的偏转角度也逐渐减小。

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。

Based on the deliberate analysis of microfacies, the authors set up the gentle-gradient braided river sedimentary model and the multi-channel and low-sinuosity meandering river sedimentary model, and think that the most favorable reservoir is overriding sand bodies of channel bar and point bar and channel bed sand bodies is sub-favorable reservoir.

在深入细致的微相分析基础上，分别建立了缓坡型辫状河与多河道低弯度曲流河两种沉积模式，认为最有利的储集砂体主要为高能水道心滩和边滩叠置砂体，其次为河床滞留砂体。

Note: A given pair of channel output jacks (e.g., Channel 1 XLR OUTPUT and Channel 1 1/4 OUTPUT) are internally connected (TIP = Pin 2, RING = Pin 3, SLEEVE = Pin 1) and can simultaneously deliver the same signal to two separate loads, but if one of the jacks is unbalanced, then the other jack will be unbalanced.

注意：通道1输出接口的XLR和TRS在内部是相通的，能够同时传递信号到两个负载，但时，一个是非平衡式的，则另一个也是非平衡式的。

Since a given pair of channel input jacks (e.g., Channel 1 XLR INPUT and Channel 1 1/4 INPUT) are internally connected (TIP = Pin 2, RING = Pin 3, SLEEVE = Pin 1), if one of the jacks is unbalanced, then the other jack will be unbalanced.

因为一对输入接口在内部是相连的，如果一个是非平衡式，那么另一个也是非平衡式。

The improved non-Manhattan channel router brings forward the crosstalk model in gridded non-Manhattan channel on the basis of the traditional crosstalk model in Manhattan channel.

在传统的曼哈顿通道中的串扰模型基础上，提出了有网格的非曼哈顿通道中的串扰模型。3。

The improved non-Manhattan channel router brings forward the crosstalk model in gridded non-Manhattan channel on the basis of the traditional crosstalk model in Manhattan channel.

将改进算法得到的非曼哈顿通道布线作为初始解，保证通道的高度即轨道不变，提出了一种基于几何原理的减小串扰的优化算法，使通道中的串扰达到最小。

In addition, since the channel frequency response is usually oversampled by the pilot sub-carriers, the channel power will be concentrated to a relatively small number of samples in the effective channel impulse response vector.

这种情况下，如果在进行基于DFT的内插之前，我们不用一个窗函数对观测到的信道频率响应向量进行加窗处理，则内插后，由能量泄漏而引起的混叠现象将导致信道估计的错误平底。

He's a pretty westernised kind of guy.

他是一个非常西化的人。

National spirit is the moral kingpin for a nation to realize common ideal and goal.

一、中华民族精神的基本内涵党的十六大报告指出：在五千多年的发展中，中华民族形成了以爱国主义为核心的团结统一、爱好和平、勤劳勇敢、自强不息的伟大民族精神。