Advanced

A polyphase filter based on CMOS inverters

Tillman, Fredrik and Sjöland, Henrik LU (2007) In Analog Integrated Circuits and Signal Processing 50(1). p.7-12
Abstract
A new idea for generation of quadrature signals on chip is presented. The topology is based on a passive RC polyphase filter, where the resistive parts are made active by using inverters. The active filter combines quadrature generation, isolation, and gain without losing quadrature performance compared to a regular RC polyphase filter. The filter technique is demonstrated in a 10 GHz front-end application where a broadband VCO, having a tuning range of 1.44 GHz, drives an active polyphase filter to generate quadrature LO signals. According to simulations the quadrature phase error shows a typical tuned behavior and stays below 0.8 degrees for the complete tuning range. Since the signal amplitude is high throughout the filter the noise is... (More)
A new idea for generation of quadrature signals on chip is presented. The topology is based on a passive RC polyphase filter, where the resistive parts are made active by using inverters. The active filter combines quadrature generation, isolation, and gain without losing quadrature performance compared to a regular RC polyphase filter. The filter technique is demonstrated in a 10 GHz front-end application where a broadband VCO, having a tuning range of 1.44 GHz, drives an active polyphase filter to generate quadrature LO signals. According to simulations the quadrature phase error shows a typical tuned behavior and stays below 0.8 degrees for the complete tuning range. Since the signal amplitude is high throughout the filter the noise is low, below 160 dBc/Hz at 10 MHz offset. The high amplitude also reduces the need for high gain tuned buffers, thereby enabling significant reductions in chip area. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
quadrature generation, CMOS, polyphase filter
in
Analog Integrated Circuits and Signal Processing
volume
50
issue
1
pages
7 - 12
publisher
Springer
external identifiers
  • wos:000242611500002
  • scopus:33845472634
ISSN
0925-1030
DOI
10.1007/s10470-006-9152-z
language
English
LU publication?
yes
id
a5d88568-5b97-4474-8b51-9fa8e240baf0 (old id 683874)
date added to LUP
2008-01-03 10:39:16
date last changed
2017-01-01 07:07:53
@article{a5d88568-5b97-4474-8b51-9fa8e240baf0,
  abstract     = {A new idea for generation of quadrature signals on chip is presented. The topology is based on a passive RC polyphase filter, where the resistive parts are made active by using inverters. The active filter combines quadrature generation, isolation, and gain without losing quadrature performance compared to a regular RC polyphase filter. The filter technique is demonstrated in a 10 GHz front-end application where a broadband VCO, having a tuning range of 1.44 GHz, drives an active polyphase filter to generate quadrature LO signals. According to simulations the quadrature phase error shows a typical tuned behavior and stays below 0.8 degrees for the complete tuning range. Since the signal amplitude is high throughout the filter the noise is low, below 160 dBc/Hz at 10 MHz offset. The high amplitude also reduces the need for high gain tuned buffers, thereby enabling significant reductions in chip area.},
  author       = {Tillman, Fredrik and Sjöland, Henrik},
  issn         = {0925-1030},
  keyword      = {quadrature generation,CMOS,polyphase filter},
  language     = {eng},
  number       = {1},
  pages        = {7--12},
  publisher    = {Springer},
  series       = {Analog Integrated Circuits and Signal Processing},
  title        = {A polyphase filter based on CMOS inverters},
  url          = {http://dx.doi.org/10.1007/s10470-006-9152-z},
  volume       = {50},
  year         = {2007},
}