Class-E power amplifier and its linearization using analog predistortion (original) (raw)

Linearity of X-band class-E power amplifiers in EER operation

IEEE Transactions on Microwave Theory and Techniques, 2000

Multifunctional RF front ends need to transmit different types of signals while maintaining efficiency and signal quality. This paper addresses efficient transmitter power amplifiers (PAs) for signals with varying peak-to-average ratios, requiring simultaneous efficiency and linearity. Linearity characterization of class-E high-efficiency PAs operating in envelope elimination and restoration (EER) mode is discussed. Specifically, a 67%-efficient 10-GHz MESFET PA is characterized in terms of its AM-AM, AM-PM conversion and intermodulation products. Measurements of intermodulation distortion are compared with harmonic-balance simulations using TriQuint's Own Model provided by the device manufacturer. It is shown experimentally and through simulations that the amplifier in the EER mode has improved linearity while maintaining high-efficiency operation.

A CMOS LOW VOLTAGE CLASS-E POWER AMPLIFIER FOR UMTS

In this paper we design a low-voltage class-E power amplifier (PA) in a standard CMOS 0.35µm integrated technology, to be used in a UMTS transceiver having the following specifications: f=1.95 GHz, V DC =1 V, P out =0.5 W. The designed class-E network accommodates the simultaneous presence of a parasitic ground inductance and losses in the switch and shunt-capacitor. The transistor is dimensioned for an optimum PAE (power added efficiency). Finally, we simulate the power control capabilities and highlight linearization methods.

Linearizing E- Class Power Amplifier by Using Memoryless Pre-Distortion

2020

Radio Frequency Power Amplifiers (PA) are essential components of wireless systems and nonlinear in a permanent way. So, high efficiency and linearity at a time are imperative for power amplifiers. However, it is hard to obtain because high efficiency Power Amplifiers are nonlinear and linear Power Amplifiers have poor efficiency. To meet both linearity and efficiency, the linearization techniques such as Digital Predistortion (DPD) has arrested the most attention in industrial and academic sectors due to provide a compromising data between efficiency and linearity. This thesis proposed on digital predistortion techniques to control nonlinear distortion in radio frequency transmitters. By using predistortion technique, both linearity and efficiency can obtain. In this thesis a new generic Saleh model for use in memoryless nonlinear power amplifier (PA) behavioral modelling is used. The results are obtained by simulations through MATLAB and experiments. We explore the baseband 13.56 ...

1 a Cmos Low Voltage Class-E Power Amplifier for Umts

2015

Abstract: In this paper we design a low-voltage class-E power amplifier (PA) in a standard CMOS 0.35µm integrated technology, to be used in a UMTS transceiver having the following specifications: f=1.95 GHz, VDC=1 V, Pout=0.5 W. The designed class-E network accommodates the simultaneous presence of a parasitic ground in-ductance and losses in the switch and shunt-capacitor. The transistor is dimensioned for an optimum PAE (power added efficiency). Finally, we simulate the power con-trol capabilities and highlight linearization methods.

Investigation on technological aspects of class E RF power amplifiers for umts applications

This paper presents results of investigation on the effects of technology on the performance of the class E power amplifier circuit. A typical class E circuit has been designed and simulated, for a typical UMTS Tx frequency (1.95 GHz) and output power ( 27dBm). Three different technologies have been used (silicon BJT, CMOS and GaAs HBT) and several important parameters (output efficiency, power added efficiency, stress put on the device) have been monitored and put in table form for comparison. Care has been taken to adapt the design in such a way to provide a maximum performance with each technology, for a fair comparison. The results are then analyzed and different tradeoffs are discussed. Possibilities for the linearization of the amplifier are considered.

Class-E CMOS RF Power Amplifier Using Voltage-Booster for Mobile Communication System

Efficiency enhancement techniques in switched Class-E power amplifier PA is usually obtained at the expense of the supply voltage. In cascode topology the supply voltage is limited by the breakdown voltage of the common-gate (CG) transistor. So voltage boosting technique is used at the CG to allow Radio Frequency (RF) swing at the gate to boost the biasing voltage above the supply voltage (VDD). This enables us to design the PA such that the cascode transistor has the same maximum drain-gate voltage. Consequently, larger signal swing will occurred at the output before encountering the breakdown. By using this combination, the gate of the NMOS is boosted above VDD and the power consumption is reduced. Simulation results using 0.13 m μ CMOS technology demonstrate 25.8 dBm output power with 38.8% Drain Efficiency at 2.4 GHz.

A 1.8 GHz Power Amplifier Class-E with Good Average Power Added Efficiency

Circuits and Systems, 2013

This paper presents a 1.8 GHz class-E controlled power amplifier (PA). The proposed power amplifier is designed with two-stage architecture. The main advantage of the proposed technique for output control power is a high 37 dB output power dynamic range with good average power adding efficiency. The measurement results show that the PA achieves a high power gain of 23 dBm and power added efficiency (PAE) by 38%. The circuit was post layout simulated in a standard 0.18 μm CMOS technology.

IJERT-An Efficient And Power Optimized Cascode Stage RF Tuned Class-E Power Amplifier

International Journal of Engineering Research and Technology (IJERT), 2012

https://www.ijert.org/an-efficient-and-power-optimized-cascode-stage-rf-tuned-class-e-power-amplifier https://www.ijert.org/research/an-efficient-and-power-optimized-cascode-stage-rf-tuned-class-e-power-amplifier-IJERTV1IS10410.pdf An efficient and power optimized cascode modulated CMOS class-E RF tuned power amplifier (PA) is presented in this paper. The main advantage of the proposed technique over other conventional modulation techniques is that it will provide a higher output power dynamic range and power added efficiency (PAE). Morever, an external supply modulator is not required if this technique is employed. A cascode modulated signal is applied to the gate of the power amplifier which in turn modulates the output power. The RF tuning of the proposed Class-E amplifier results in a PAE of approximately 64% which is an improvement over other conventional techniques. The cascode modulated CMOS class-E RF tuned power amplifier operates at a frequency of 2.4 GHz with 20.1 dBm output power and is implemented using 180 nm technology.

Using Analog Predistortion for Linearizing Class A–C Power Amplifiers

Analog Integrated Circuits and Signal Processing, 2000

An analog 5th order, complex-valued polynomial predistortion IC has been built to linearize the behavior of RF power amplifiers. The predistorter can be used either at baseband or low IF frequencies and it was tested using a simple IF amplifier that could be biased to operate in classes A, AB, B and C. Intermodulation products can be reduced by 20 to 30 dB in classes A and AB over a bandwidth of several MHz. In classes B and C the shape of nonlinearity is such that a low-order polynomial predistortion function is not sufficient for linearizing them.

Linearity of X-band Class-E Power Amplifiers in a Digital Polar Transmitter

2007 IEEE/MTT-S International Microwave Symposium, 2007

This paper discusses the linearity of a class-E Xband PA in a digital polar transmitter. The PA is nonlinear since it is compressed by 2.2 dB when achieving a 59% PAE at 10 GHz. Load-pull is performed under a two4one test and the resulting optimal efficiency impedance is found to be over 30% different from the single4one load-pull. In addition standard two4one load-pull measurements indicate that the impedance for max P0ut coincide with worst nonlinearity (IMD). Surprisingly, in the two4one polar load-pull, impedance for max P0ut differs significantly from the impedance corresponding to worst IMD. Therefore, under polar modulation a different matching circuit should be designed for optimal linearity and efficiency. The PA is part of a digital polar transmitter which enables linearization including phase predistortion, with IMD levels over 11 dB lower than in the standard two4one test. Load-pull performed on the polar class-E PA shows that the level of intermodulation products varies for different signals input into the PA.