Large-signal Characterization Research Articles

Automation of a bank of measurements for large signal characterization

El articulo presenta una estrategia para la medicion y caracterizacion de circuitos de Radio Frecuencia y microondas (RF/Microondas), aplicados a sistemas modernos de comunicaciones inalambricas, por medio del diseno de un software que permite capturar y controlar, de manera remota, los datos obtenidos en los equipos de medicion utilizados –en este caso, un analizador vectorial de redes R&S ZVA8 y un multimetro digital DM3061–. Como evidencia, se presenta el resultado de esta estrategia a partir de la caracterizacion de un amplificador de potencia [PA] altamente eficiente, a una frecuencia de prueba de 2.4 GHz.

Multiple-band large-signal characterization of millimeter-wave double avalanche region transit time diode

A large-signal method based on non-sinusoidal voltage excitation model is used to study the DC and RF characteristics of Double Avalanche Region (DAR) Silicon Transit Time diode. A large-signal simulation program based on drift-diffusion model is developed for this study. The simulation results show the existence of several distinct negative conductance bands in the admittance characteristics separated by positive conductance. Thus the DAR device is capable of delivering RF power not only at the design frequency but also at several frequency bands higher than the design frequency band in the mm-wave regime. A comparative study with DDR Si device designed to deliver RF power at a particular mm-wave frequency band shows that DAR Si device is capable of delivering significantly higher RF power not only at the designed mm-wave frequency band, but also at higher frequency bands.

Large-signal characterizations of DDR IMPATT devices based on group III–V semiconductors at millimeter-wave and terahertz frequencies

Large-signal (L-S) characterizations of double-drift region (DDR) impact avalanche transit time (IMPATT) devices based on group III–V semiconductors such as wurtzite (Wz) GaN, GaAs and InP have been carried out at both millimeter-wave (mm-wave) and terahertz (THz) frequency bands. A L-S simulation technique based on a non-sinusoidal voltage excitation (NSVE) model developed by the authors has been used to obtain the high frequency properties of the above mentioned devices. The effect of band-to-band tunneling on the L-S properties of the device at different mm-wave and THz frequencies are also investigated. Similar studies are also carried out for DDR IMPATTs based on the most popular semiconductor material, i.e. Si, for the sake of comparison. A comparative study of the devices based on conventional semiconductor materials (i.e. GaAs, InP and Si) with those based on Wz-GaN shows significantly better performance capabilities of the latter at both mm-wave and THz frequencies.

Large-signal characterization of DDR silicon IMPATTs operating in millimeter-wave and terahertz regime

The authors have carried out the large-signal characterization of silicon-based double-drift region (DDR) impact avalanche transit time (IMPATT) devices designed to operate up to 0.5 THz using a large-signal simulation method developed by the authors based on non-sinusoidal voltage excitation. The effect of band-to-band tunneling as well as parasitic series resistance on the large-signal properties of DDR Si IMPATTs have also been studied at different mm-wave and THz frequencies. Large-signal simulation results show that DDR Si IMPATT is capable of delivering peak RF power of 633.69 mW with 7.95% conversion efficiency at 94 GHz for 50% voltage modulation, whereas peak RF power output and efficiency fall to 81.08 mW and 2.01% respectively at 0.5 THz for same voltage modulation. The simulation results are compared with the experimental results and are found to be in close agreement.

Large-signal characterization of DDR silicon IMPATTs operating up to 0.5 THz

Large-signal (L-S) characterization of double-drift region (DDR) impact avalanche transit time (IMPATT) devices based on silicon designed to operate at different millimeter-wave (mm-wave) and terahertz (THz) frequencies up to 0.5 THz is carried out in this paper using an L-S simulation method developed by the authors based on non-sinusoidal voltage excitation (NSVE) model. L-S simulation results show that the device is capable of delivering peak RF power of 657.64 mW with 8.25% conversion efficiency at 94 GHz for 50% voltage modulation; whereas RF power output and efficiency reduce to 89.61 mW and 2.22% respectively at 0.5 THz for same voltage modulation. Effect of parasitic series resistance on the L-S properties of DDR Si IMPATTs is also investigated, which shows that the decrease in RF power output and conversion efficiency of the device due to series resistance is more pronounced at higher frequencies especially at the THz regime. The NSVE L-S simulation results are compared with well established double-iterative field maximum (DEFM) small-signal (S-S) simulation results and finally both are compared with the experimental results. The comparative study shows that the proposed NSVE L-S simulation results are in closer agreement with experimental results as compared to those of DEFM S-S simulation.

Large-Signal Measurements and Nonlinear Characterization of an Analog Frontend for Passive UHF CMOS RFID Transponders

This work focuses on the comprehensive measurement-based nonlinear characterization of an integrated analog frontend, which is implemented into a passive multifunctional radio-frequency-identification (RFID) transponder. It explains the necessity and the practical execution of large-signal characterization and nonlinear analyses of the frontend at ultra-high-frequencies. The fundamentals of the implemented source-pull measurement setup are described in detail and the results of selected measurements are presented. To the authors knowledge, this is the first time that a passive RFID frontend is characterized by nonlinear large-signal measurements.

DESIGN OF LOW-LOSS AND HIGHLY-SELECTIVE CMOS ACTIVE BANDPASS FILTER AT K-BAND

In this paper, a second-order Chebyshev active bandpass fllter (BPF) with three flnite transmission zeros is presented. The fllter utilizes a tapped-inductor feedback technique to compensate resistive losses of on-chip inductors, and a shunt-feedback inductor between input and output ports to achieve the transmission zeros. Moreover, one transmission zero is in the lower stopband, and two transmission zeros are in the upper stopband, thus improving the selectivity of the fllter signiflcantly. The fllter is designed and fabricated in a standard 0.18-m CMOS technology with a chip area of 0:57mm £ 0:65mm including all testing pads. The circuit draws 6mA from a 0.7-V supply voltage. Additionally, the fllter achieves a 1.65-dB insertion loss and 13.2-dB return loss with a 17% 3-dB bandwidth at 23.5GHz. The measured NF and input P1dB is 6.7dB and i3:5dBm. The rejection levels at the transmission zeros are greater than 15.2dB. Finally, the large-signal characterizations are also investigated by the 1-dB compression point (P1dB) of the fllter.

Magnetically Controlled Electronic Ballasts With Isolated Output: The Variable Transformer Solution

In this paper, the variable transformer solution is presented as a step forward in magnetically controlled electronic ballasts. The proposed technique takes advantage of the device's equivalent series inductance to provide a new flexible way for lamp's luminous flux regulation. Output electrical isolation and constant frequency operation are also guaranteed by the proposed realization. A simple method for large-signal characterization of the variable transformer is described. An FH 14W/840 Osram lamp was chosen to validate this new technique and experimental results clearly show its adequate behavior.

Highly Efficient InP/GaAsSb DHBTs With 62% Power-Added Efficiency at 40 GHz

We report the large-signal load-pull characterization of InP/GaAsSb double heterojunction bipolar transistors (DHBTs) with fT and fMAX cutoff frequencies as high as 380 and 320 GHz, respectively. Measurements were performed at 40 GHz in a passive load-pull system to characterize the output power and power-added-efficiency (PAE) performance. A PAE of 60% with an output power of 10 dBm (corresponding to power densities of approximately 870 mW/mm and 1.45 mW/μm2) was achieved in class AB operation. This excellent performance can be attributed to the low offset and knee voltages associated with the InP/GaAsSb type-II heterojunctions. To the best of our knowledge, the present performance exceeds published state-of-the-art results for HBTs at a frequency of 40 GHz.

Accurate large-signal characterization of LDMOSFET transistor in package

In this article, we present an accurate characterization of the RF LDMOSFET transistors for the extracting of the large-signal model. They are generally available encapsulated in package. A measurement of the package parameters are made only by removing the semiconductor chip. The transistor is then characterized by conventional method. The same component can be used in the desired function, thereby avoiding the technological dispersions. The LDMOSFET transistor used is a BLF2043F (NXP semiconductors). To validate our method, we implemented a 2.5-GHz 10-W power amplifier. The measured and simulated results match very well. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:575–579, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25800

Nonlinear characterization of GaN HEMT

DC I—V output, small signal and an extensive large signal characterization (load-pull measurements) of a GaN HEMT on a SiC substrate with different gate widths of 100 μm and 1 mm have been carried out. From the small signal data, it has been found that the cutoff frequencies increase with gate width varying from 100 μm to 1mm, owing to the reduced contribution of the parasitic effect. The devices investigated with different gate widths are enough to work in the C band and X band. The large signal measurements include the load-pull measurements and power sweep measurements at the C band (5.5 GHz) and X band (8 GHz). When biasing the gate voltage in class AB and selecting the source impedance, the optimum load impedances seen from the device for output power and PAE were localized in the load-pull map. The results of a power sweep at an 8 GHz biased various drain voltage demonstrate that a GaN HEMT on a SiC substrate has good thermal conductivity and a high breakdown voltage, and the CW power density of 10.16 W/mm was obtained. From the results of the power sweep measurement at 5.5 GHz with different gate widths, the actual scaling rules and heat effect on the large periphery device were analyzed, although the effects are not serious. The measurement results and analyses prove that a GaN HEMT on a SiC substrate is an ideal candidate for high-power amplifier design.

An impedance and power flow measurement system suitable for on-wafer microwave device large-signal characterization

A reflection based and thru-less de-embedding technique for impedance and absolute power flow measurements suitable for on-wafer large-signal characterization of microwave transistors is proposed. The developed system was tested for both 50 Ω and non-50 Ω terminated passive and active devices and the results obtained are compared with those obtained with commercial instruments. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.

Thru-less calibration algorithm and measurement system for on-wafer large-signal characterisation of microwave devices

A reflection-based thru-less de-embedding technique for voltage and current waveforms and absolute power flow measurements suitable for on-wafer large-signal characterisation of microwave transistors is proposed. Based on the novel calibration technique developed, which does not require any special `golden standard` for waveform calibration purposes, a comprehensive and relatively inexpensive power flow, impedance and waveform measurement system, using the microwave transition analyser as a two-channel receiver, is developed. The proposed calibration algorithm is fast, simple and accurate for power de-embedding and waveform measurements. This kind of on-wafer power de-embedding and waveform measurement is helpful in the design of switching-mode power amplifiers. The developed system was tested for both 50Ω and non-50Ω terminated passive and active devices, and the obtained results show very good agreement with those obtained with commercial instruments.

Magnetically-controlled dimming technique with isolated output

New advances on magnetically-controlled electronic ballasts can grant the ability to dim the lamp and simultaneously guarantee output electrical isolation. By means of a variable transformer, the model of which is presented, this new technique is developed and experimentally verified. In addition, a simple method for the large signal characterisation of the transformer is described. An FH 14W/840 Osram lamp was chosen to validate this new technique and experimental results clearly show its adequate behaviour.

Multisine Calibration for Large-Signal Broadband Measurements

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Classical calibration techniques use single-sine-wave measurements to maximize the signal-to-noise ratio (SNR). In large-signal characterization, the large number of instrument states to be calibrated results in unacceptably long calibration times. The proposed approach uses multisine excitation signals during the calibration to reduce the calibration time while having only a marginal influence on the measured device response. </para>

Versatile High-Frequency Inverter Module for Large-Signal Inductive Loads Characterization Up to 1.5 MHz and 7 kW

This paper presents the challenges encountered and the solutions adopted during the construction of a versatile voltage-fed high-frequency series-resonant half-bridge inverter module. It is used in the large-signal power generator of an inductive load characterization test-bench operating from 1 kHz up to 1.5 MHz and up to 7-kW output power for a variety of loads. Square wave operation of the module is established slightly above resonance under zero voltage switching conditions. Output power is controlled by means of a variable dc bus while resonant conditions are fixed by means of two adjustable capacitor banks. The control of every test-bench block and the triggering waveform generation is performed digitally with a field programmable gate array. Two prototype modules have been designed, constructed and evaluated for operation in half-bridge and full-bridge configurations showing rugged and stable operation under hazardous conditions such as voltage transients as high as dv/dt = 50 kV/mus at 1 MHz during the characterization of domestic induction heating loads.

New Time-Domain Voltage and Current Waveform Measurement Setup for Power Amplifier Characterization and Optimization

This paper reports a novel voltage and current waveform measurement system suitable for large-signal transistor and power amplifier characterization and optimization. This technique is original in its use of a double six-port (SP) reflectometer as a homodyne vector network analyzer, which is calibrated in magnitude and phase by means of a reference multiharmonic signal generator, to measure the waveforms at the output terminal of the device. An active branch load-pull setup is used to control the source impedance at the fundamental frequency, and the load impedance at the fundamental, second, and third harmonic frequencies. The capability of the proposed SP reflectometer-based configuration is demonstrated experimentally, by measuring the voltage and current waveforms of a GaAs metal-semiconductor field-effect transistor that is biased in class AB and tuned for maximum efficiency. To assess the level of accuracy of the proposed method, the same waveforms were also measured using a microwave-transition-analyzer-based system. A comparison of the results shows that the proposed SP reflectometer setup obtains results accurate enough for power amplifier characterization with lower equipment cost.

Simplified Analytical Model and High Power Characteristics of InGaP/GaAs HBTs at X-Band

Simplified large-signal analysis and high power characterization of InGaP/GaAs heterojunction bipolar transistors (HBTs) at X-band are reported. The simplified analytical model suggested in this work allows a first order prediction of the power performance trends as functions of device physical parameters. The solution to nonlinear equations governing the large signal behavior of the transistor is found by an iterative approach. The impact of different large signal parameters on the power performance of HBTs has been analyzed. Under class B operation, a 10-finger 2times20mum2 HBT at VCE= 10V achieves a maximum output power of 1.08W (5.4W/mm) with power-added efficiency of 44%

A new configuration to improve the active loop technique for transistor large signal characterization in the Ka band

AbstractThis article presents a new configuration to improve the conventional active loop technique with pre‐matching. This reduces the power requirements of the loop amplifier when synthesizing high reflection coefficient for high power transistors. The active loop technique is very efficient in characterizing power transistors but the output power of the loop amplifier can be a strong limitation as it can exhibit non‐linear behavior when high power is needed. The proposed new configuration improves the active loop capabilities as it allows a larger reflection coefficient to be synthesized with higher linearity of the loop amplifier. Theoretical results show the interest of the new active loop and experimental measurements in the Ka band validate the linear behavior improvement of the active loop for high reflection coefficients. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 589–593, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22220

A 210-GHz bandwidth electrooptic sampler for large signal characterization of InP-based components

We propose an electrooptic sampler at 1.55 μm (wavelength), which uses an ion-irradiated InP-based photoconductor for the optical-to-electrical conversion and a fiber-mounted LiTaO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> crystal as the electric-field sensor. A measurement bandwidth of 210 GHz is obtained with a signal-to-noise ratio higher than 17 dB. These results are found to be independent of the amplitude of the 2.1-ps excitation pulse, which reaches values as high as 0.81 V. Large signal characterization of InP-based components are thus allowed. The performance of our system is validated by test measurements performed on coplanar waveguides made on semi-insulating InP substrates.