1) Nyquist sampling theorem
奈奎斯特抽样定理
2) nyquist sampling theorem
奈奎斯特采样定理
1.
In view of the problem of that the nyquist sampling theorem astricts the sample rate and precision Measurement of high frequency signal must cost highly to match suitable high sample rate, in this paper we present a Frequency Measurement Algorithm based on Sub-nyquist Sampling.
针对奈奎斯特采样定理对采样率的限制,对高频信号进行精密测量需要花费昂贵成本来得到适合的高采样率问题,本文提出一种欠采样的频率测量算法,即用不符合采样定律的特定低采样率对高频信号进行采集,采用互相关算法对采集所得的数据进行处理,最终实现了对高频信号的精密测量。
3) Nyquist's theorem
奈奎斯特定理
4) Nyquist sampling rate
奈奎斯特采样率
5) Nyquist
奈奎斯特
1.
According to the design principle of the Nyquist filter of FIR, this article design a FIR filter which uses root raised cosine function of 33 taps.
本文根据奈奎斯特(Nyquist)FIR滤波器的设计原理,设计了33阶根升余弦函数FIR滤波器,并提出了用FPGA实现其硬件电路的方案,最后用Modelsim和matlab工具进行了仿真验证。
6) Nyquist sampling criteria
奈奎斯特取样准则
1.
The results of computer simulation show that this method does not require the sampling interval to satisfy the Nyquist sampling criteria and only needs few sampling points to attain very high testing precision,so we can improve the testing speed and effectively reduce the truncation error caused by finite scanning plane on the premise of ensuring t.
计算机模拟结果表明 ,这种方法不要求取样间隔一定要满足奈奎斯特取样准则 ,只需较少的取样点数即可达到很高的测试精度 ,从而能够在保证测试精度的前提下 ,提高测试速度并有效减小由于有限扫描面所引起的截断误差 。
补充资料：斯特瓦尔特定理
斯特瓦尔特(stewart)定理
设已知△abc及其底边上b、c两点间的一点d，则有
ab2·dc+ac2·bd-ad2·bc＝bc·dc·bd．
证明 在图2－6中，作ah⊥bc于h．为了明确起见，设h和c在点d的同侧，那么由[[广勾股定理]]有
ac^2=ad^2＋dc^2-2dc·dh，(1)
ab^2=ad^2+bd^2+2bd·dh． (2)
用bd乘(1)式两边得
ac^2·bd=ad^2·bd+dc^2·bd-2dc·dh·bd，(1)′
用dc乘(2)式两边得
ad^2·dc=ad^2·dc＋bd^2·dc＋2bd·dh·dc．(2)′
由(1)′+(2)′得到
ac^2·bd+ab^2·dc=ad^2(bd＋dc)+dc^2·bd＋bd^2·dc
=ad^2·bc+bd·dc·bc．
∴ab^2·dc＋ac^2·bd-ad^2·bc=bc·dc·bd．
说明：补充资料仅用于学习参考，请勿用于其它任何用途。