1)  Under-sampling
Under-sampling
2)  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。
3)  under-sampling
欠抽样
补充资料：two-stage sampling
分子式：
CAS号：

性质：第一步将总体划分为若干个样本群，从中抽取某些样本群，第二步是从已抽中的各样本群内所包括许多个样本单位中，抽取若干个样本单位。它与分层抽样和整群抽样不同占二步抽样在抽样的两个阶段，都只是抽取部分样品，而分层抽样在抽样的第一阶段是抽取全部样品，在第二阶段只抽取部分样品，整群抽样在抽样的第一阶段是抽取部分样品，在第二阶段是抽取全部样品。

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