A Self-Tuning Technique for Optimization of Dual Band LNA
2008 (English)In: European Wireless Technology Conference (EuWiT), EuMW 2008, October 27-28, 2008, Amsterdam, The Netherlands, IEEE , 2008, 178-181 p.Conference paper (Refereed)
This paper presents a self-tuning technique for optimization of a dual band LNAthat can be used in a flexible RF front-end suitable for IEEE 802.11a/b/g WLANapplications. With this tuning technique the LNA can perform self-calibrationfor the optimal performance. A possible shift in resonance frequency due toprocess and temperature variations can be compensated by this method. Theproposed self-tuning technique is implemented by using a simple RF detector atthe LNA output. Based on the DC value provided by this detector the LNA istuned for a maximum gain through the tuning loop, which incorporates ADC,digital base-band and DAC. We show that the tuning error can be within halfLSB of ADC provided the DAC and ADC resolutions are constraint by aspecified condition. For 4-bit case this value corresponds to a gain error of0.4 dB. The LNA has been implemented in 0.2μm GaAs process offered byOMMICTM. In measurements the LNA achieves a gain of 15.1 dB and 21.6 dBin the upper and lower band, respectively, with corresponding NF of 3.8 dB and2.8 dB. In the lower band the measured IIP3 is -3 dBm and 1dB_CP is -8 dBm.
Place, publisher, year, edition, pages
IEEE , 2008. 178-181 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-14862ISBN: 978-2-87487-008-8OAI: oai:DiVA.org:liu-14862DiVA: diva2:25372