HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Comments
View Comments: Newest First|Oldest First|Threaded View
William K.
User Rank
Platinum
Designing an FIR filter, or any other kind of filter.
William K.   9/9/2013 10:45:24 AM
NO RATINGS
Since creating a filter design would be a very smal portion of my job activities, I would need to find some source of the design, either published or for sale. So presentations like this do wind up being a very useful resource on many occasions.

ttemple
User Rank
Platinum
DFT of coefficients
ttemple   9/6/2013 8:10:52 AM
NO RATINGS
Jon,

I didn't know that performing an FFT on the filter coefficients would produce the same characteristic as the filter.  That is interesting.  I have always used software to produce the coefficients, and somewhat trusted the output.  I do usually verify the overall gain by summing the coefficients, however.

It seems that the FFT output produced by 65 coefficients of 0.015625 is skewed by the zero padding.  I would expect the FFT of a constant value to have all energy content to appear in the 0Hz bin, and absolutely nothing in the other frequency bins.  By padding it out to 128 points with zeroes, you have essentially created a square wave with approximately a 50% duty cycle, and the FFT result looks like it (the odd harmonic content).



Partner Zone
Latest Analysis
A middle school team from Rochester, Mich., has again nabbed the grand prize in the annual international Future City Competition, which drew students from 37 regions of the United States, as well as from England and China.
The actor captured imaginations and inspired scientists and engineers all over the world in his role as Star Trek's Mr. Spock.
You know you're an engineer if you chuckle whenever anyone says "centrifugal force," or you find yourself at the airport studying the baggage handling equipment.
The word “smart” is becoming the dumbest word around. It has been applied to almost every device and system in our homes. In addition to smartphones and smart meters, we now hear about smart clothing and smart shoes, smart lights, smart homes, smart buildings, and every trendy city today has its smart city project. Just because it has a computer inside and is connected to the Web, does not mean it is smart.
Are you being paid enough? Do you want a better job? According to a recent survey Manpower released just before Engineers Week, employers and engineers don't see eye-to-eye about the state of US engineers' skills and experience.
More:Blogs|News
Design News Webinar Series
2/25/2015 11:00 a.m. California / 2:00 p.m. New York
12/11/2014 8:00 a.m. California / 11:00 a.m. New York
12/10/2014 8:00 a.m. California / 11:00 a.m. New York
11/19/2014 11:00 a.m. California / 2:00 p.m. New York
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Mar 9 - 13, Implementing Motor Control Designs with MCUs and FPGAs: An Introduction and Update
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  67


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2015 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service