Periodicity-Enabled Size Reduction of Symbol Based Predistortion for High-Order QAM
Artikel i vetenskaplig tidskrift, 2022

We experimentally demonstrate a novel size reduction approach for symbol-based look-up table (LUT) digital predistortion (DPD) of the transmitter impairments taking advantage of the periodicity in the pattern-dependent distortions. Compared to other reduced-size LUT schemes, the proposed method can significantly lessen the storage memory requirements with negligible performance penalty for high-order modulation formats. To further alleviate the storage memory restriction, a twice reduced-size LUT scheme is proposed to provide further size reduction. Importantly, given a targeted memory length, we verify the importance of averaging over sufficient occurrences of the patterns to obtain a well-performing LUT. Moreover, it is necessary to evaluate the performance of LUT-based DPD using random data. Finally, we demonstrate a neural network (NN) based nonlinear predistortion technique, which achieves nearly identical performance to the full-size LUT for all employed constellations and is robust against a change of modulation format. The proposed techniques are verified in a back-to-back transmission experiment of 20 Gbaud 64-QAM, 256-QAM, and 1024-QAM signals considering 3 and 5 symbol memory. The performance of the LUT-based DPD is further validated in a noise loading experiment.

signal processing

Look-up table

transmitter nonlinearity compensation

neural network

predistortion

Författare

Zonglong He

Chalmers, Mikroteknologi och nanovetenskap, Fotonik

Jinxiang Song

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

Kovendhan Vijayan

Chalmers, Mikroteknologi och nanovetenskap, Fotonik

Christian Häger

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

Alexandre Graell I Amat

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

Henk Wymeersch

Chalmers, Elektroteknik, Kommunikation, Antenner och Optiska Nätverk

Peter Andrekson

Chalmers, Mikroteknologi och nanovetenskap, Fotonik

Magnus Karlsson

Chalmers, Mikroteknologi och nanovetenskap, Fotonik

Jochen Schröder

Chalmers, Mikroteknologi och nanovetenskap, Fotonik

Journal of Lightwave Technology

0733-8724 (ISSN) 1558-2213 (eISSN)

Vol. 40 18 6168-6178

Frigöra full fiberoptisk kapacitet

Knut och Alice Wallenbergs Stiftelse (KAW 2018.0090), 2019-07-01 -- 2024-06-30.

Ämneskategorier

Telekommunikation

Kommunikationssystem

Signalbehandling

DOI

10.1109/JLT.2022.3191464

Mer information

Senast uppdaterat

2024-07-27