Linearity and Noise Improvements of Driver-Stage Envelope-Injection Power Amplifier With Amplitude and Phase Shaping Functions for 5G New Radio Application

Wei-Ting Tsai,Chong-Yi Liou,Shau-Gang Mao,Zheng-An Peng

doi:10.1109/access.2019.2933475

Wei-Ting Tsai, Chong-Yi Liou + Show 2 more

Open Access

https://doi.org/10.1109/access.2019.2933475

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Abstract

The driver-stage envelope-injection power amplifier (EIPA) consisting of the wideband linear amplifier with the envelope amplitude and phase shaping functions is proposed. This SiGe BiCMOS EIPA is implemented without the switch amplifier and the off-chip inductor used in the conventional envelope tracking circuit. To improve the in-band distortion and the out-of-band intermodulation of power amplifier, the envelope amplitude and phase shaping functions of the driver-stage EIPA are investigated to equally generate the two-tone fundamental terms and symmetrically minimize the third-order intermodulations (IM3s) by using the three-tone harmonic balance analysis. The maximum linear output power of the driver-stage EIPA with the corresponding envelope amplitude and phase shaping functions is 23.5 dBm for -30-dBc third-order intermodulation distortion (IMD3) specification. The 2.35-GHz 256-quadrature amplitude modulation Time-Division Duplexing signal with the 50-MHz bandwidth is applied to validate the usefulness of the driver-stage EIPA for 5G New Radio (NR) applications. Compared to the conventional envelope tracking PA and the dc-supply PA, the measured results show that the out-of-band noise of the proposed driver-stage EIPA is significantly reduced and the maximum average output power is increased from 21 dBm to 23.5 dBm at the -30-dBc adjacent channel leakage ratio (ACLR) specification and the ACLR and error vector magnitude are improved by 5 dB and 1.3 % at 23.5-dBm average output power, respectively.

Highlights

Growing demand for ubiquitous wireless connectivity with high data rates, high connection density, high spectral efficiency, and low network latency is driving the deployment of fifth generation (5G) wireless communication system by 2020 [1]–[3]
Compared with the dc-supply power amplifier (PA) shown in Fig. 11(a), the driver-stage envelopeinjection power amplifier (EIPA) with the envelope amplitude and phase shaping functions achieves the 13-dB IMD3 improvement at 23.5-dBm output power and the asymmetric IMD3 effect is reduced from 20 dB to 0.1 dB at 19.4-dBm output power
The envelope amplitude and phase shaping functions of the wideband linear amplifier are investigated to enhance the linearity of the EIPA by controlling the envelope amplitude Eenv and the envelope phase φ3

Summary

INTRODUCTION

Growing demand for ubiquitous wireless connectivity with high data rates, high connection density, high spectral efficiency, and low network latency is driving the deployment of fifth generation (5G) wireless communication system by 2020 [1]–[3]. A novel driver-stage EIPA shown, consisting of the wideband linear amplifier with the envelope amplitude and phase shaping functions on the collector of the PA driver stage, is implemented to improve the in-band and out-of-band characteristics of 5G signal, such as error vector magnitude (EVM), ACLR, and IMD3. 3 to 8, the specific envelope amplitude and phase shaping functions demonstrate the usefulness of the linearity improvement of EIPA by achieving the symmetric and minimum IM3 and the equal fundamental terms. The vector signal analyzer with Keysight 89600 VSA software is used to measure the power spectra, ACLR, and EVM of the 5G NR TDD modulation signal

TWO-TONE CONTINUOUS SINUSOIDAL WAVE

Findings

CONCLUSION