L. Pantoli

RF and microwave high‐Q floating active inductor design and implementation

Summary In this paper, a high-Q floating active inductor (FAI), suitable for RF and microwave applications, is presented. The proposed FAI is based on two cascaded pairs of highly linear capacitance gyrators, which provide a symmetric and reciprocal structure. The proposed FAI shows fully symmetrical two-port characteristics, high quality factor and high linearity. As a feasibility demonstration, a prototype of the designed FAI has been fabricated, together with an LC series band-pass filter. At the operating frequency, the real part of the impedance of the equivalent FAI is very low (Req = 0.0039 Ω), providing a very high quality factor. The filter has a central frequency of 430 MHz and a −3 dB bandwidth of about 9 MHz. Copyright

Single transistor high linearity and wide dynamic range active inductor

In this paper, an active inductor AI with high linearity and high dynamic range, including a minimum number of components, is presented. The AI is composed by a single transistor, and by a passive compensation network; the latter allows the control of the values of both the inductance and the series resistance.

Complete and Systematic Simulation Tools for Frequency Divider Design

In this study, a two-stage simulation method is presented for the efficient design of frequency dividers using harmonic balance. The first stage uses a modified conversion matrix approach to select the subharmonic loads of the active element enabling the frequency division by a given order N. The second stage makes use of an auxiliary generator to obtain and modify the sub-harmonic-power curve versus the input power or input frequency. Systematic simulation tools are used to eliminate common hysteresis phenomena, which require additional constraints to minimize the disturbance of the original frequency-division bands and output power. A harmonic-balance technique to distinguish between subcritical flip bifurcations, associated with hystereses, and supercritical ones is presented, to our knowledge, for the first time. A technique is also derived to transform subcritical bifurcations into supercritical ones. The techniques have been successfully applied to a frequency divider by 2 at 630 MHz.

TUNABLE ACTIVE FILTERS FOR RF AND MICROWAVE APPLICATIONS

In this paper, we present a low-voltage tunable active filter for microwave applications. The proposed filter is based on a single-transistor active inductor (AI), that allows the reduction of circuit area and power consumption. The three active-cell bandpass filter has a 1950 MHz center frequency with a -1 dB flat bandwidth of 10 MHz (Q ≈ 200), a shape factor (30–3 dB) of 2.5, and can be tuned in the range 1800–2050 MHz, with constant insertion loss. A dynamic range of about 75 dB is obtained, with a P1dB compression point of -5 dBm. The prototype board, fabricated on a TLX-8 substrate, has a 4 mW power consumption with a 1.2 V power supply voltage.

HIGH QUALITY FACTOR L-BAND ACTIVE INDUCTOR-BASED BAND-PASS FILTERS

In this letter, a tunable high-Q active inductor with high dynamic range is presented. The equivalent inductance and resistance values can be tunable in a wide frequency range by changing the compe...

Stability Analysis and Design Criteria of Paralleled-Device Power Amplifiers Under Large-Signal Regime

This paper describes a method for the stability analysis and stabilization criteria in multi-device paralleled power amplifiers (PA) under large-signal operating conditions. The symmetry of the amplifier is exploited for a simple and effective study of odd- and even-order modes. The overall stability analysis is transformed into a sequence of analyses on single-mode single-transistor large-signal equivalent amplifiers, which are carried out by using a conversion matrix approach. Examples of application of the method are provided on a 9-GHz GaAs pHEMT monolithic-microwave integrated-circuit (MMIC) PA and a 590-MHz power silicon bipolar hybrid microwave integrated-circuit (HMIC) PA.

Compact Tuning Circuit for Enhanced Linearity in a Ku-Band MMIC VCO

This work describes a compact, tunable linearization circuit able to provide enhanced linearity characteristics and low sensitivity of the VCO output signal, also regarding temperature variation between -30°C and +70°C. The proposed solution is applied to the design of a Ku-Band MMIC voltage-controlled oscillator in push-push configuration. The chip has been realized by UMS Foundry in HBT technology with the HB20M process. The measured oscillation bandwidth spans from 10.52 to 12.53 GHz with a tuning range of about the 16%; sensitivity has an average value of 200 MHz/V, while the phase noise at 100 kHz of frequency offset from the carrier at 11.7 GHz is -98.5 dBc/Hz.

Large-signal stability of oscillators by the conversion matrix method

In this paper a method for the control of the stability of power amplifiers is extended to oscillators under large-signal conditions. It is based on the conversion matrix of the oscillator, computed from a harmonic balance simulation. This allows the suppression of possible spurious frequencies or the intentional generation of spurious signals (e.g. at sub-harmonic frequency).

An assessment on low-voltage low-power integrated single transistor active inductor design for RF filter applications

In this paper an assessment of bandpass filter implementation based on a single transistor Active Inductor (AI) is presented. A minimum number of components, high linearity, high dynamic range, active inductor is first designed and then used for high frequency bandpass filter. The AI is designed by the use a compensation network that allows to control both the inductance and its series resistance value in the design phase. Analytical formulation is also presented and a simulated IC demonstrator proposed for the filter that has a center frequency of 2000MHz (useful for radio and radar applications) and a 3dB bandwidth of about 6MHz with a quality factor of about 330.

A GAUSSIAN MONOCYCLE PULSE GENERATOR/MODULATOR FOR UWB RADIOS APPLICATIONS

In this paper, we present, at transistor level, a very low complexity Gaussian monocycle pulse generator/modulator for DPSK low voltage and low power tunable ultra-wideband (UWB) applications. The pulse generator, simulated in a SMIC 0.13 μm CMOS technology, provides a tunable, both in pulse width duration and repetition time, Gaussian monocycle compliant with the sub-GHz ETSI band and suitable to be used in UWB radio applications. The preliminary IC simulation results show a pulse duration from 1 ns up to 20 ns with good pulse symmetry and with the DPSK modulation capability. The circuit power consumption is about 1 mW from a 1.8 V power supply.