Investigation on technological aspects of class E RF power amplifiers for umts applications (original) (raw)

On the feasibility of application of class E RF power amplifiers in UMTS

This paper investigates the feasibility of the application of class E RF power amplifiers in UMTS. A typical class E circuit has been designed and simulated, in conjunction with a linearization scheme based on the EER principle. The EER testbench uses ideal building blocks, since the emphasis is on the operation of the amplifier itself. Three different technologies have been used for the active device (Si BJT, GaAs HBT and CMOS) in order to examine the influence of the device technology on the PA performance. Relevant parameters have been monitored and put in the table form, for comparison of technologies. The simulation results indicate that class E PAs can successfully be used for power amplification of WCDMA RF signal and that GaAs technology is offering the highest efficiency.

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.

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.

A 1GHZ CLASS E POWER AMPLIFIER FOR WIRELESS APPLICATIONS

In this paper, a class E power Amplifier (PA) suitable for wireless applications (Wi-Max, cellular phones, cordless phones etc,) is proposed by using the device of RF3931GaN HEMT (Gallium Nitrate High Electron Mobility Transistor).The proposed class E power Amplifier for achieving high output power and increasing gain up to 14.327dB and operates in the frequency range of 1GHz. The designed Power Added Efficiency (PAE) is 64% after optimization and the maximum source power achieved is 32dBw.

Analysis and Design a 2.5 GHz Class-E Power Amplifier in Two Configurations

There are two circuit configurations that commonly used for Class-E power amplifiers, the Infinite DC-feed or Shunt capacitor configuration and the Finite DC-feed or Shunt inductor. Albeit these circuit configurations are not essentially different, however they show different behavior and performance. In this paper we have compared these Class-E configurations at 2.5 GHz. For this purpose, we have designed two class-E circuits, one with Infinite DC-feed configuration and the other with Shunt inductor configuration. We have used the GaN High Electron Mobility Transistor (HEMT) in both designs. Optimized simulations showed 69% drain efficiency, 64% PAE, and 21.46 dBm load power, in the case of Infinite DC-feed design and 71% efficiency, 64.5% PAE, and 15.93 dBm load power in the case of Shunt inductor design. It is obvious that we should consider the importance of PAE inhigh power circuits and the importance of DE in low power circuits. The results propose that Infinite DC-feed design...

Class-E Amplifier Design Improvements for GSM Frequencies

The Journal of Engineering Research [TJER], 2011

Efficient power amplifiers are essential in portable battery-operated systems such as mobile phones. Also, the power amplifier (PA) is the most power-consuming building block in the transmitter of a portable system. This paper investigates how the efficiency of the power amplifier (which is beneficial for multiple applications in communcation sector) can be improved by increasing the efficiency of switching mode class E power amplifiers for frequencies of 900 MHz and 1800 MHz. The paper tackles modeling, design improvements and verification through simulation for higher efficiencies. This is the continuation of previous work by the authors. These nonlinear power amplifiers can only amplify constant-envelope RF signals without introducing significant distortion. Mobile systems such as Advanced Mobile Phone System (AMPS) and Global System for Mobile communications (GSM) use modulation schemes which generate constant amplitude RF outputs in order to use efficient but nonlinear power a...

Design of a 2 GHz GaAs HBT-based Class-E power amplifier

This paper presents a design procedure for the GaAs HBT-based Class-E power amplifier for 2 GHz. An empirical approach, based on load-pull and source-pull sim- ulations has been used to find an optimal impedance point for high efficiency operation. The simulation results show that a single-stage single-ended Class-E PA can achieve PAE higher than 70 %, output power of 24 dBm and transducer power gain of 15 dB when driven from a standard 50 Ohm signal generator. Three different solutions for the imple- mentation of the load network are discussed, including both lumped and distributed components. designed and implemented in various technologies and in different frequency bands. In many papers it is shown how the circuit deviates from its nominal operation when dif- ferent kinds of non-ideal effects are taken into account. These effects include finite-inductance DC-feeding coil, finite Q-factor of the load network, non-zero fall time of the collector/drain current, variations in duty c...

Analysis and design of class-O RF power amplifiers for wireless communication systems

Analog Integrated Circuits and Signal Processing, 2016

In this paper, we present analysis, design and show experimental results of a new type of CMOS based power amplifier (PA) known as class-O Aref et al. (ISSCC Digest of Technical Papers, 2015). Modern CMOS based PAs design is constrained by three fundamental trade-offs, i.e. linearity, efficiency and reliability. More precisely, for a standalone PA, unless advanced and expensive solutions are employed, no such PA architecture exists which is able to meet aforementioned design trade-offs. Theoretical insight is needed to understand the origin of performance trade-offs and the possible solutions to counter them. Class-O is a novel out-of-the-box solution to meet these tough challenges. Our prototype amplifier is a highly linear low-band 706 MHz 4G long term evolution (LTE) compatible class-O RF power amplifier in 130 nm CMOS technology for handheld wireless applications. The class-O architecture uses two sub-amplifiers working together as one grand PA. These two sub-amplifiers are commonsource (CS) and common-drain (CD) amplifiers working in parallel feeding a common load with high linearity without the need for digital predistortion (DPD). The prototype chip is measured and characterized with continuous wave (CW), modulated signal and reliability measurements. With CW measurements, 1-dB compression point (P 1 dB) of 30.6 dBm and peak power added efficiency (PAE) of 45.2 % is achieved. For the modulated signal measurements, the amplifier is tested with 16-QAM 20 MHz LTE signal with peak-to-average-power ratio of 6.54 dB. The amplifier meets the stringent LTE specs with an adjacent channel power ratio (ACPR) less than-30 dBc for both EUTRA and UTRA1 with average output power of 27 dBm and PAE above 20 %. Owing to the voltage following between gate source junctions in the common-drain amplifier in addition to cascode structure of common source amplifier, the stress is significantly reduced at the transistor terminals. The reliability is demonstrated by operating the amplifier in nominal and worst voltage-standing-wave-ratio (VSWR) conditions.

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.