Tunable CMOS LNA Using a Variable Inductor for a Reconfigurable RF Circuit

Hirotaka SUGAWARA  Kenichi OKADA  Kazuya MASU 

Publication
IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences  Vol.E92-A  No.2  pp.401-410
Publication Date: 2009/02/01
Online ISSN: 1745-1337
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Section on Analog Circuit Techniques and Related Topics)
Category: 
Keyword: 
reconfigurable RF,  variable inductor,  LNA,  MEMS, 

Full Text: PDF(1.5MB)

Summary: 
This paper proposes a novel wide-tunable CMOS low-noise amplifier (LNA) using a variable inductor. The variable inductance can be tuned by shielding the magnetic flux, which uses a metal plate above the inductor. The metal plate can be moved using a MEMS actuator. At the present time, the MEMS actuator has not been implemented yet. In this paper, we present a feasibility study on the proposed LNA using the variable inductor. The proposed LNA uses two variable inductors for input and output impedance matching-tuning. The LNA achieves a power gain (PG) of over 10 dB at a tuning range of 1.6-3.2 GHz.