Skip to content Skip to navigation

Connexions

You are here: Home » Content » Multirate Filtering: Filter-Design Exercise in MATLAB (Chinese Version)

Navigation

Recently Viewed

This feature requires Javascript to be enabled.

Multirate Filtering: Filter-Design Exercise in MATLAB (Chinese Version)

Module by: Douglas L. Jones, Swaroop Appadwedula, Matthew Berry, Mark Haun, Jake Janovetz, Michael Kramer, Dima Moussa, Daniel Sachs, Brian Wade, Patrick Frantz, Kanglin Wang. E-mail the authors

Based on: Multirate Filtering: Filter-Design Exercise in MATLAB by Douglas L. Jones, Swaroop Appadwedula, Matthew Berry, Mark Haun, Jake Janovetz, Michael Kramer, Dima Moussa, Daniel Sachs, Brian Wade

User rating (How does the rating system work?)
Ratings

Ratings allow you to judge the quality of modules. If other users have ranked the module then its average rating is displayed below. Ratings are calculated on a scale from one star (Poor) to five stars (Excellent).

How to rate a module

Hover over the star that corresponds to the rating you wish to assign. Click on the star to add your rating. Your rating should be based on the quality of the content. You must have an account and be logged in to rate content.

:
(0 ratings)

Summary: You will design a low-pass finite impulse-response filter using the zero-placement method in MATLAB. The filter can be used as an anti-aliasing and anti-imaging filter in a multirate system.

Note: Your browser may not currently support MathML. See our browser support page for additional details. You can always view the correct math in the PDF version.

滤波器设计练习

使用置零的方法为Multirate Filtering: Introduction中的多频采样系统设计滤波器。一个长度为 N N 的FIR滤波器的 z z-变换在 z-1 z -1 中是一个多项式，这个多项式可被因式分解为 N−1 N 1 项。

Hz= h 0 + h 1 z-1+ h 2 z-2+⋯= z 1 −z-1 z 2 −z-1 z 3 −z-1⋯ H z h 0 h 1 z -1 h 2 z -2 ⋯ z 1 z -1 z 2 z -1 z 3 z -1 ⋯ (1)

利用这一关系在单位圆上的 ±3π8 ± 3 8 , ±π2 ± 2 , ±5π8 ± 5 8 , ±3π4 ± 3 4 , ±7π8 ± 7 8 和 ±π ± 处放置12个复数零来设计一个低通滤波器（用于多频采样系统中的anti-aliasing和anti-imaging滤波器）。你设计的这个滤波器既可被用作 FIR 1，也可被用作 FIR 3。而对于滤波器 FIR 2 则通过在单位圆上的 ±π4 ± 4 and ±3π4 ± 3 4 处放置四个等间距的零来设计一个低通滤波器（用于多频采样系统的 anti-aliasing 和 anti-imaging 滤波器）。调整设计好的滤波器参数以确保在任何频率下增益都不超过1。

在MATLAB中根据给定的零点来计算滤波器参数，并以此来设计滤波器。你可以使用MATLAB的poly函数。在MATLAB中键入help poly来获取使用细节。

在确定了滤波器参数后，使用MATLAB中的freqz函数来画出频率响应曲线。你会发现这些滤波器的频率响应具有很大的增益。通过除以适当数值的方法来调整滤波器参数，以确保增益最大不超过1。所得到的频率响应是否和你根据z-平面上零点位置所预计的频率响应相一致？

Content actions

Give Feedback:

E-mail the module authors | Rate module ( How does the rating system work?)

Rating system

Ratings

Ratings allow you to judge the quality of modules. If other users have ranked the module then its average rating is displayed below. Ratings are calculated on a scale from one star (Poor) to five stars (Excellent).

How to rate a module

Hover over the star that corresponds to the rating you wish to assign. Click on the star to add your rating. Your rating should be based on the quality of the content. You must have an account and be logged in to rate content.

(0 ratings)

Download:

Module PDF

Add module to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections directly in Connexions. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need a Connexions account to use 'My Favorites'.

| A lens (?)

Definition of a lens

Lenses

A lens is a custom view of Connexions content. You can think of it as a fancy kind of list that will let you see Connexions through the eyes of organizations and people you trust.

What is in a lens?

Lens makers point to Connexions materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

Who can create a lens?

Any individual Connexions member, a community, or a respected organization.

What are tags? tag icon

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks