查询词典 signal noise ratio

Information of system auto and cross spectrum, auto and cross correlation. coherent function, signal to noise ratio, frequency response and impulse response was established to help the study and arrangement of the module components.

由力规及加速规两量测之时域讯号，经快速富利叶转换，计算其自频谱及互频谱，再经反富氏转换回时域之自相关及互相关函数、相通函数、讯噪比、频率响应函数、脉冲响应函数。

Based on the model, closed-form expressions for cumulative distribution function of the output signal-to-interference plus noise ratio and symbol error rate of MIMO MRC systems with equal-power and unequal-power CCI are derived respectively.

在此基础上，分别推导出具有相等功率和互不相等功率的共信道干扰下系统输出信干噪比的累积分布函数和误符号率的闭合表达式。

Actually ,signals are processed from low frequency domain to high one by modulation firstly and alternating current amplification secondly.It can also improve anti-interference抗干扰 ability of circuit and signal to noise ratio of signals.

实际中往往采用更有效的先调制而后交流放大，将信号从低频区推移到高频区，也可以提高电路的抗干扰能力和信实际中往往采用更有效的先调制而后交流放大，将信号从低频区推移到高频区，号的信噪比。

Simulation results show that the proposed algorithm has a faster convergence rate and much less computational complexity, and the output bit error rate and signal-to interference-plus noise ratio performance are superier to the PASTd blind multiuser detection algorithm and close in on the singular value decomposition group blind multiuser detection algorithm.

仿真结果表明，所提算法收敛速度快，输出信干噪比和误码率性能优于PASTd盲多用户检测，逼近奇异值分解(singular value decomposition， SVD)群盲多用户检测，并保持了较低的计算复杂度。

And if 64 points per period was sampled, the signal to noise ratio could be improved by more then 5.6 times by demodulate algorithm.

在每周期采样64点的情况下，解调算法可将信噪比提高5.6倍以上

This present algorithm further distinguishes itself through sufficiently utilizes the advantage that the vector sensors provide from other beam space DOA algorithms in several regards: 1 beams are formed in the vector-field domain; 2 produce at moderate signal-to-noise ratio estimation performance comparable to the traditional scale array methods;3 these vector-field beams are formed blindly using no apriori source information and coarse estimates of the direction cosine are derived to start off MUSICs iterative search so it demand less computation; 4 deploy agilely , since the fact that the output channel is various .

本文提出了矢量传感器阵列的自适应综合校准补偿方法，还提出利用单矢量传感器速度协方差矩阵分解来求解目标源方位，使得我们不要求校准源是合作性的，也无需知道校准源的先验知识，这比起常规辅助源校准方法具备较大宽容性。随着高性能阵列处理技术及数字信号处理硬件的快速发展和矢量传感器制造工艺的不断成熟，矢量传感器将在新型水雷、低频远程智能鱼雷、声纳浮标、低频拖曳线列阵和新型舰壳声纳，灵巧传感终端，战场监视系统，反隐形雷达，通讯等军民用领域取得良好的发展应用前景。

First, the closed-form expressions of the receiver output signal-to-noise ratio distribution are derived and validated via simulation.

推导了存在反馈时延时，STD系统的输出信噪比分布和BPSK调制的误比特率表达式。

To meet the needs of detection of space faint objects for a telescope with large aperture and short focal,a binding drawtube telescope scheme to detect space object is presented to overcome the shortcomings that focal length grows and field of view shrinks with the increasing of aperture size in traditional telescope for space detection.The software methods are used to stack collected images to restrain background random noises and to improve image Signal to Noise Ratio and the detecting ability of the whole system.

为了满足空间暗弱目标探测对大口径、短焦距望远镜系统的要求，克服普通望远镜随着口径的增加焦距变长、视场变小的不足，提出了将多镜筒捆绑在一起对同一空域进行观测，通过软件的方式对采集的图像进行叠加来抑制背景随机噪声、提高图像的信噪比和系统的整体探测能力的设想。

All phase Walsh transform ; biorthogonal transform ; dual biorthogonal base vectors ; JPEG image compression algorithm ; discrete cosine transform; peak signal to noise ratio

全相位沃尔什变换；双正交变换；对偶双正交基向量； JPEG压缩编码算法；离散余弦变换；峰值信噪比

Material and Methods:From March,2008 to January,2009,250 patients(146 Males and 104 Females,ranged from 18 to 82 years old,mean age was 48 years old) enrolled in the First Affiliated Hospital of Kunming Medical College were performed dual energy scan(Group A,200 patients) and Neuro-DSA scan(Group B,50 patients) using DSCT.The patients were randomly divided into Group A and Group B.Regarding to the justification of scan protocol,100 patients in Group A were selected as sub-group to explore the scan protocol.The image quality Was analyzed both in four categories(4.0/60、4.5/60、4.0/70、4.5/70) of flow rate and total amount of contrast-enhanced material and in three categories(100—150HU、150—200HU、200-250HU) of CT value of left common carotid artery.The comparison of two scan approach was based on image quality,radiation does, postprocessing methods,time of scanning and subtraction and data storage amount.To validate the diagnostic capability of DE-CTA virtual unenhanced images,100 patients in Group A were undergoing head scan both in routine non-contrast program and DE-CTA virtual unenhanced program.Mean CT values,signal-to-noise ratio,image quality,sensitivity of lesion identification,and radiation does were applied to comparison.According to diagnostic results of dual energy of cerebral arterial angiography,62 patients out of 200 patients in Group A were confirmed with cerebral vessel lesions,the results were complied with DSA findings(the time between the two methods were within 1 week).

材料与方法收集2008年3月到2009年1月间在昆明医学院第一附属医院行DSCT CTA检查者250例(男性146例，女性104例，年龄范围18-82岁，平均48岁)，随机分为A、B两组，A组200例行双能量头颅CTA扫描；B组50例行Neuro-DSA扫描。A组前100例按对比剂不同流率和总量分为4组(4.0/60、4.5/60、4.0/70、4.5/70)对图像质量比较；按触发时左颈总动脉内平均CT位分3组(100—150HU、150—200HU、200-250HU)，比较图像质量的差异；对A、B两组血管图像质量、辐射剂量、后处理的方法、扫描和后处理时间及数据的容量进行比较分析；A组中前100例行常规与DE-CTA虚拟平扫的平均CT值、信号噪声比、图像质量、病灶显示情况、辐射剂量的比较分析；A组中行DSA检查62例(两种方法间隔时间均1周内)，比较两种检查方法诊断结果是否符合，并对其中24例动脉瘤行动脉瘤部位、数目、形态、瘤颈显示程度、瘤颈大小及瘤体长径和短径的比较研究。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。