An Enhanced Design of Multi-Band RF Band Pass Filter Based on Tunable High-Q Active Inductor for Nano-Satellite Applications

Abstract

This paper describes the design of a novel cascode-grounded tunable active inductor and its application in an active band-pass filter (BPF) suitable for multi-band radio frequency (RF) front-end circuits. The proposed active inductor circuit uses feedback resistance to improve the equivalent inductance and the quality factor. The novelty of this work lies on the use of a few number of multi-finger transistors, which allows reducing strongly the power consumption and the silicon area. In other words, we demonstrate that the use of variable P-type Metal-Oxide-Semiconductor (PMOS) resistor and controllable current source have a good potential for wide tuning in terms of inductance value, quality factor and frequency operation. The RF BPF is realized using the proposed active inductor with suitable input and output buffer stages. The tuning of the center frequency for multi-band operation is achieved through control voltages. The designed active inductor and RF BPF have been implemented in a standard 0.13[Formula: see text][Formula: see text]m Complementary Metal Oxide Semiconductor (CMOS) technology. The simulation results are compared between schematic and post-layout design for inductance value, quality factor, transmission coefficient S21 and noise. This design yields encouraging results: the inductance value can be tuned from 10.94 to 44.17[Formula: see text]nH with an optimal quality factor around 2,581. In addition, the center frequency of the BPF can be tuned between 2 and 4.84[Formula: see text]GHz with an average insertion loss of [Formula: see text][Formula: see text]dB. Throughout this range, the noise figure is between 10.49 and 9.22[Formula: see text]dB with an input referred 1[Formula: see text]dB compression point of [Formula: see text][Formula: see text]dBm and IIP3 of 7.36[Formula: see text]dBm. The filter occupies 25.43[Formula: see text][Formula: see text]m of active area without pads and consumes between 2.38 and 2.84[Formula: see text]mW from a 1[Formula: see text]V supplying voltage.