An adaptive impedance tuning CMOS circuit for ISM 2.4-GHz band
(2005) In IEEE Transactions on Circuits and Systems Part 1: Fundamental Theory and Applications 52(6). p.1115-1124- Abstract
- The difficulties encountered in matching an antenna to its optimal impedance are reduced with an adaptive 0.35-mu m CMOS circuit based on several switched shunt capacitors arranged in capacitor banks and on a few external series inductors. As high-quality inductors are difficult to obtain in CMOS, the inductors are placed either in an low-temperature cofired ceramic (LTCC) substrate or is a lumped component outside the core circuit. The circuits, presented here through a range of simulations, are optimized to function within the ISM 2.4-GHz band, but the general approach employed to improve matching can be used for other frequency bands as well. The circuits discussed provide a VSWR <= 2 match for every impedance with VSWR <= 5.... (More)
- The difficulties encountered in matching an antenna to its optimal impedance are reduced with an adaptive 0.35-mu m CMOS circuit based on several switched shunt capacitors arranged in capacitor banks and on a few external series inductors. As high-quality inductors are difficult to obtain in CMOS, the inductors are placed either in an low-temperature cofired ceramic (LTCC) substrate or is a lumped component outside the core circuit. The circuits, presented here through a range of simulations, are optimized to function within the ISM 2.4-GHz band, but the general approach employed to improve matching can be used for other frequency bands as well. The circuits discussed provide a VSWR <= 2 match for every impedance with VSWR <= 5. There is a 1-dB power loss for a perfect 50 Omega -> 50 Omega transformation, a break-even point at VSWR = 1.5, and a 3-dB increase in delivered power for VSWR = 4.3. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/236170
- author
- Sjöblom, Peter LU and Sjöland, Henrik LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- CMOS, antenna tuning unit (ATU), impedance matching, impedance tuning, reconfigurable matching, unit (ITU), ISM, capacitor, bank, switched capacitor
- in
- IEEE Transactions on Circuits and Systems Part 1: Fundamental Theory and Applications
- volume
- 52
- issue
- 6
- pages
- 1115 - 1124
- publisher
- IEEE - Institute of Electrical and Electronics Engineers Inc.
- external identifiers
-
- wos:000229818800009
- scopus:22144488501
- ISSN
- 1057-7122
- DOI
- 10.1109/TCSI.2005.849116
- language
- English
- LU publication?
- yes
- id
- cf512eef-16a9-4bff-8d1b-b007763b0982 (old id 236170)
- date added to LUP
- 2016-04-01 16:38:54
- date last changed
- 2024-04-17 02:49:34
@article{cf512eef-16a9-4bff-8d1b-b007763b0982, abstract = {{The difficulties encountered in matching an antenna to its optimal impedance are reduced with an adaptive 0.35-mu m CMOS circuit based on several switched shunt capacitors arranged in capacitor banks and on a few external series inductors. As high-quality inductors are difficult to obtain in CMOS, the inductors are placed either in an low-temperature cofired ceramic (LTCC) substrate or is a lumped component outside the core circuit. The circuits, presented here through a range of simulations, are optimized to function within the ISM 2.4-GHz band, but the general approach employed to improve matching can be used for other frequency bands as well. The circuits discussed provide a VSWR <= 2 match for every impedance with VSWR <= 5. There is a 1-dB power loss for a perfect 50 Omega -> 50 Omega transformation, a break-even point at VSWR = 1.5, and a 3-dB increase in delivered power for VSWR = 4.3.}}, author = {{Sjöblom, Peter and Sjöland, Henrik}}, issn = {{1057-7122}}, keywords = {{CMOS; antenna tuning unit (ATU); impedance matching; impedance tuning; reconfigurable matching; unit (ITU); ISM; capacitor; bank; switched capacitor}}, language = {{eng}}, number = {{6}}, pages = {{1115--1124}}, publisher = {{IEEE - Institute of Electrical and Electronics Engineers Inc.}}, series = {{IEEE Transactions on Circuits and Systems Part 1: Fundamental Theory and Applications}}, title = {{An adaptive impedance tuning CMOS circuit for ISM 2.4-GHz band}}, url = {{http://dx.doi.org/10.1109/TCSI.2005.849116}}, doi = {{10.1109/TCSI.2005.849116}}, volume = {{52}}, year = {{2005}}, }