1) undersampling projection
欠采样投影
1.
This algorithm increases the contrast between the target and background and improves the resolution of target details by using adaptive bi-threshold mapping and undersampling projection,which reduces the redundant gray level and broadens the dyn.
该算法通过对原始图像的直方图进行自适应双阈值映射和欠采样投影处理,实现了对图像灰度级的重新分配;在减少冗余灰度级的基础上,有效拓宽了目标部分占据的动态范围,既提高了目标与背景间对比度又突出了目标细节层次。
2) spacing sample projection
间隔采样投影
3) undersampling
欠采样
1.
Uniform undersampling technique of bandpass signal and its engineering application in software digital IF receiver;
带通欠采样技术及在数字中频软件接收机中的工程应用
2.
Project of Convex Set Method for Reconstructing A Super-resolution Image from Multiframe Undersampling Images;
一种多幅欠采样图像的凸集投影超分辨率重建方法
3.
Application of bandpass undersampling principle in software radio;
带通欠采样定理在软件无线电中的应用
4) sub-sampling
欠采样
1.
Time-delay estimation for sub-sampling sinusoidal signals;
欠采样条件下的正弦信号时差估计
2.
In order to break through the limitation of Electronic analog-to-digital converter in speed and time-delay precision,a wideband digital frequency measurement method based on optical sub-sampling is proposed.
为了突破高速电模数转换器采样速率和时延控制精度对测频带宽的限制,文中提出了一种采用光脉冲欠采样的超宽带、高分辨率数字测频方法。
3.
In the algorithm for estimation of frequency of ultra-wideband LFM signal based on multi-channel and sub-sampling,even tiny error of the remainder can lead to huge error of the frequency.
针对基于多速率欠采样的超宽带LFM信号瞬时频率估计方法中,余数的很小测量误差将导致很大的测频误差问题,提出一种基于欠采样的超宽带LFM信号参数估计算法。
5) under-sampling
欠采样
1.
According to the characteristics of the wayside frequency-shift signal spectrum,and based on a great number of computer emulators and real-time experiments and on non-complete periods sampling,the feasibility of applying the under-sampling technology to the real-time FFT analytical method of tramroad FSK signal is validated.
针对轨道移频信号的频谱特点,采用欠采样技术对轨道移频信号进行非整周期的采样,经过计算机仿真实验,验证了基于非整周期采样方法对轨道移频信号进行实时傅里叶变换(FFT)分析检测的可行性,证明采样方法满足检测指标的要求。
2.
Based on the theoretic modeling and analysis of the IF GPS signals,an accurate software simulator of IF GPS signals is implemented in Matlab/Simulink,the effects of noise,under-sampling and receiver clock error are also simulated.
在对中频GPS信号理论建模与分析的基础上,采用Matlab/Simulink构建了一种精确的数字中频GPS信号软件模拟器,考虑了噪声、欠采样以及接收机时钟误差等的影响。
3.
The theoretical analysis has proved that in the condition of under-sampling, because the paired echoes will be appeared, the system’s multi-object resolution will be affected.
理论分析证明:在欠采样情况下,脉冲压缩后会出现成对回波,因而系统的多目标分辨能力受到影响;由于信号带宽的损失,脉压输出回波信号的主瓣展宽,距离分辨力下降;另外,主瓣幅度或相位还会受到调制。
6) sub-Nyquist sampling
欠采样
1.
Using Different Frequencies Method to Solve Bandpass sub-nyquist sampling;
欠采样信号多采样频率处理方法
2.
In view of the present sub-Nyquist sampling frequency estimation method,in order to overcome the existing problems such as complex arithmetic and difficult to engineer realizing,the paper puts forward a three-sample rates switching frequency estimation method based in virtual instruments.
为了克服现有的欠采样频率估计方法存在的算法复杂、工程实现困难等问题,本文提出了一种基于虚拟仪器的三采样率切换的频率估计方法。
3.
Based on an auxiliary time-delay channel and ESPRIT approach,a new algorithm for wide band frequency estimation with sub-Nyquist sampling was proposed.
基于时延和旋转不变子空间技术 (ESPRIT) ,本文提出了一种新的欠采样宽频带信号频率的高分辨估计方法 。
补充资料：滤波反投影或卷积反投影
滤波反投影或卷积反投影
影像学术语。当代影像学设备进行影像重建的数学方法。在直接用扫描后所获得的投影轨迹剖面图反投影重建出的CT图像中，无法避免角度卷入条纹伪影(angular aliasing streaks)造成的模糊和失真。这种现象与被扫描层面的空间频率中高频信息的损失有关。使用一种精密的数学方法去除这种模糊。称为“展现”(unfolding)或去卷积(deconvolution)，即在反投影前使用一种数学的“滤器”或卷积函数对原始数据进行修正，然后再进行反投影。两步数学处理过程合称为滤波(修正后)反投影或卷积(后)反投影。这种方法的优点是处理过程简单，速度快，所得图像逼真、清晰。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条