Highly efficient unsymmetrical doherty power amplifier with DPD for LTE application

Self Cite

This article presents a modified GaN Doherty power amplifier (PA) for 100 MHz long‐term evolution (LTE)‐advanced application at 2.5 GHz. To improve load modulation and consistency of the output power and efficiency in the operation bandwidth, a method was proposed by choosing optimal load impedances in Class C mode, properly increased gate bias voltage and optimized input matching network for the design of the peaking amplifier. When driven with 100 MHz LTE‐advanced signals, the designed PA achieves adjacent channel leakage ratio of −49 dBc after digital predistortion at 9 dB back‐off output power of about 40.5 dBm with efficiency of 42%. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:391–395, 2015

Section: Introductionmentioning

confidence: 99%

Doherty power amplifier with enhanced in‐band load modulation for 100 MHz LTE‐advanced application

Xia

Zhu

2014

Self Cite

Section: Introductionmentioning

confidence: 99%

“…Additionally, the power amplifier is regarded as the component which determines the power efficiency of the overall mobile system, as the amplifier consumes most of the power from the battery. Efficiency improvement methods for power amplifiers remain one of the major challenges in today's pursuit of efficient mobile systems . Recently, one challenging issue in the research on power amplifiers is the replacement of heterojunction bipolar transistor (HBT)‐based power amplifiers with CMOS‐based power amplifiers .…”

Section: Introductionmentioning

confidence: 99%

Numerical Analysis of the Supply Voltage of a Switching Mode RF CMOS Power Amplifier to Enhance Its Efficiency

Hwang

Seo

Lee

et al. 2013

In this work, we analyzed numerically the effects of an interstage capacitor related to the power-added efficiency of a power amplifier. In particular, we calculated the power consumption values induced by the on-resistances and short-circuit current of the class-Dtype driver-stage. After analyzing the results, the interstage capacitor between the driver and the power stages was removed to improve the overall efficiency. By removing the interstage capacitor, the supply voltage for the driver stage can be decreased compared to a normal power amplifier. The power consumption at the on-resistance of the driver stage can be reduced and the power consumption induced by the shortcircuit current can be reduced. Additionally, we measured the power consumption at the driver stages to verify the calculated results. In the experimental results, we noted improved efficiency of the proposed amplifier, while its output power was nearly identical to that of a normal amplifier.In this section, we describe numerically the effects of the supply voltage of the driver stage related to the overall efficiency of

“…Generally, the efficiency of a RF power amplifier determines the overall efficiency of the mobile system in which it is used, because the power amplifier is often the component that uses most of the battery power . Efficiency improvement methods for power amplifiers are still regarded as challenging issues in the area of RFIC design . However, a general power amplifier only reaches its peak efficiency in a maximum output power region .…”

Section: Introductionmentioning

confidence: 99%

Investigation of the power transistor size related to the efficiency of switching‐mode RF CMOS power amplifier

Hwang

Seo

Park

et al. 2013

In this work, we analyzed the efficiency of a switching‐mode RF CMOS power amplifier with the following design parameters: the on resistance and the parasitic capacitance of the power transistor. The power amplifier is composed of a class‐D type driver stage and a class‐E type power stage. The power consumption of the driver stage, the load impedance of the power stage, and the loss of the output matching networks are considered for a numerical analysis. We investigated the normalized drain efficiency according to the variable supply voltage of the power stage for polar transmitter applications. From the simulated results of the power amplifier, we successfully proved the feasibility of using the numerical analysis. The designed power amplifier is implemented using 0.13 μm RF CMOS process to verify the numerical results by means of an experiment. A distributed active transformer is used for an output matching network. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:110–117, 2014