World Library  
Flag as Inappropriate
Email this Article

Center frequency

Article Id: WHEBN0000577454
Reproduction Date:

Title: Center frequency  
Author: World Heritage Encyclopedia
Language: English
Subject: Family Life Radio, Vermont Public Radio, Family Life Network, Bible Broadcasting Network, Yellowstone Public Radio
Collection: Electrical Engineering, Frequency Domain Analysis, Telecommunication Theory
Publisher: World Heritage Encyclopedia

Center frequency

The frequency axis of this symbolic diagram may be linearly or logarithmically scaled. Except in special cases, the peak response will not align precisely with the center frequency.

In electrical engineering and telecommunications, the center frequency of a filter or channel is a measure of a central frequency between the upper and lower cutoff frequencies. It is usually defined as either the arithmetic mean or the geometric mean of the lower cutoff frequency and the upper cutoff frequency of a band-pass system or a band-stop system.

Typically, the geometric mean is used in systems based on certain transformations of lowpass filter designs, where the frequency response is constructed to be symmetric on a logarithmic frequency scale.[1] The geometric center frequency corresponds to a mapping of the DC response of the prototype lowpass filter, which is a resonant frequency sometimes equal to the peak frequency of such systems, for example as in a Butterworth filter.

The arithmetic definition is used in more general situations, such as in describing passband telecommunication systems, where filters are not necessarily symmetric but are treated on a linear frequency scale for applications such as frequency-division multiplexing.[2]


  1. ^ John T. Taylor and Qiuting Huang (1997). CRC Handbook of Electrical Filters. CRC Press.  
  2. ^ Julie K. Petersen (2003). Fiber Optics Illustrated Dictionary. CRC Press.  

External links

  • Calculations and comparisons between the geometric mean and the arithmetic mean
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.