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Description: 采样率小于一个连续时间信号最大频率的2倍时就叫undersampling，欠采样，根据抽样定理，当fs>=2fmax，也就是oversampling，过采样时，数字信号才能重建成原来的模拟信号，欠采样重建会发生混叠
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Size: 645641 |
Author: sheweidong |
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Description: 采样率小于一个连续时间信号最大频率的2倍时就叫undersampling，欠采样，根据抽样定理，当fs>=2fmax，也就是oversampling，过采样时，数字信号才能重建成原来的模拟信号，欠采样重建会发生混叠-Sampling rate of a continuous-time signal is less than the maximum frequency of 2 times is called undersampling, bandpass sampling, according to sampling theorem, when fs
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Size: 645120 |
Author: sheweidong |
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Description: 该程序模拟成像过程中的欠采样模型，可以从一帧高分辨力图像得到一帧欠采样的低分辨力图像。-The program simulated imaging process due to the sampling model, we can start a high-resolution images to be an undersampling of low-resolution images.
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Size: 89088 |
Author: 陈艳 |
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Description: Zooming: oversampling and Shrinking : undersampling
Zooming requires two steps:
Creation of new pixel locations,
Assignment of gray levels to those new locations.
To shrink an image by one-half, delete every other row and column.
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Size: 2048 |
Author: riyadh |
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Description: AdaBoost元算法属于boosting系统融合方法中最流行的一种，说白了就是一种串行训练并且最后加权累加的系统融合方法。
具体的流程是：每一个训练样例都赋予相同的权重，并且权重满足归一化，经过第一个分类器分类之后，
计算第一个分类器的权重alpha值，并且更新每一个训练样例的权重，然后再进行第二个分类器的训练，相同的方法.......
直到错误率为0或者达到指定的训练轮数，其中最后预测的标签计算是各系统*alpha的加权和，然后sign（预测值）。
可以看出，训练流程是串行的，并且训练样例的权重是一直在变化的，分错的样本的权重不断加大，正确的样本的权重不断减小。
AdaBoost元算法是boosting中流行的一种，还有其他的系统融合的方法，比如bagging方法以及随机森林。
对于非均衡样本的处理，一般可以通过欠抽样(undersampling)或者过抽样(oversampling)，欠抽样是削减样本的数目，
过抽样是重复的选取某些样本，最好的方法是两种进行结合的方法。
同时可以通过删除离决策边界比较远的样例。
-AdaBoost boosting systems dollar fusion algorithm is the most popular one, it plainly systems integration approach is a serial train and final weighted cumulative.
Specific process is: Each training example is given equal weight, and the weights satisfy normalization, after the first classifiers after
Calculating a first classifier weights alpha value for each sample and updates right weight training, and then the second classifier training, the same way .......
0, or until the specified error rate training rounds, wherein the label is the calculation of the final prediction system* alpha weighted and then sign (predicted value).
As can be seen, the training process is serial, and weight training examples is always changing, the right of the wrong sample weight continued to increase, the right to correct sample weight decreasing.
AdaBoost algorithm is an element, as well as other methods of boosting popular systems integration, such as bagging and random forest method.
For
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Size: 2048 |
Author: iihaozl |
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Description: In this paper, we firstly construct a wide-band undersampling array, then present a novel frequency and
direction of arrival (DOA) estimation method for a very wide frequency band (2-18GHz). Choosing a set
of appropriate sampling frequencies and antenna spacing, the method can provide unambiguous frequency
and DOA estimation under the sub-Nyquist spatio-temporal sampling. The proposed method can reduce
the computational complexity as it does not need the 2-D spectral peak search and high-dimensional
eigen decomposition. In addition, the proposed method uses the temporal filtering to cascade the
frequency estimation and DOA estimation so that the DOA estimation results are automatically paired
with corresponding frequency. Simulation results demonstrate the effectiveness of the novel method.
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Size: 436224 |
Author: rouakgb241 |
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Description: 代码附后
本设计结合 PCM 的抽样、量化、编码原理，利用 MATLAB 软件编程和绘图功能，完 成了对脉冲编码调制（PCM）系统的建模与仿真分析。课题中主要分为三部分对脉冲编码 调制（PCM）系统原理进行建模与仿真分析，分别为采样、量化和编码原理的建模仿真。 同时仿真分析了采样与欠采样的波形、均匀量化与 A 律 13 折线非均匀量化的量化性能及 其差异。通过对脉冲编码调制（PCM）系统原理的仿真分析，设计者对 PCM 原理及性能 有了更深刻的认识，并进一步掌握 MATLAB 软件的使用。 -This design combined with PCM sampling, quantization, coding theory, using MATLAB software programming and graphics capabilities, completed the pulse code modulation Modeling and Simulation (PCM) System. The issue is divided into three portions of pulse code modulation (PCM) system principle of modeling and simulation analysis, namely sampling, modeling and simulation quantization and coding principles. While the simulation waveform sampling and undersampling, uniform quantization and A-law 13 fold non-uniform performance and the quantized difference. By pulse code modulation (PCM) system principle of simulation analysis, the designer of the PCM principles and performance of a deeper understanding and further master the use of MATLAB software.
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Size: 1548288 |
Author: 高山 |
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Description: In the field of communication, signal, sampling, sampling, undersampling, transformation of matlab simulation and its spectrum.you can learn more communication knowledge by it.
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Size: 1024 |
Author: wuming |
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Description: ADXL362是一款超低功耗、3轴MEMS加速度计，输出数据
速率为100 Hz 时功耗低于2 μA ，在运动触发唤醒模式下功耗
为270 nA 。与使用周期采样来实现低功耗的加速度计不同，
ADXL362没有通过欠采样混叠输入信号；它采用全数据速
率对传感器的整个带宽进行采样(The ADXL362 is an ultra-low power, 3 axis MEMS accelerometer with output data
When the speed is 100 Hz, the power consumption is less than 2 A, and the power dissipation in the motion triggered wake-up mode
For 270 nA. Unlike using periodic sampling to achieve low power dissipation, accelerometers are different,
ADXL362 does not aliasing input signals via undersampling; it uses full data speed
The rate is sampled across the entire bandwidth of the sensor)
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Size: 1472512 |
Author: 蒋平
|
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Description: 对语音信号进行分析处理，欠采样、过采样的区别(Analysis and processing of speech signal, the difference between undersampling and oversampling)
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Size: 168960 |
Author: 何老三 |
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