Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: PAPR reduction

Sortuj według:

Ogranicz wyniki do:

A Simple Nonlinear Companding Transfrom for Nonlinear Compensation of Direct-Detection Optical OFDM Systems

Ngo Trang T., Nguyen Nhan D.

International Journal of Electronics and Telecommunications

2020

Vol. 66, No. 3

515--520

In direct-detection OFDM systems, the nonlinear effects caused by optical modulation and fiber transmission can degrade the system performance severely. In this study, we propose a new nonlinear companding transform to improve the performance of direct detection optical OFDM transmission systems. The demonstration is realized by Monte-Carlo simulation of the intensity modulation and direct detection DCO-OFDM optical transmission system at 40 Gbps over a 80 km of standard single mode fiber link. The influence of the companding parameters on the performance of system in different nonlinear transmission conditions has been investigated via simulation.

Interleaving Technique Implementation to Reduce PAPR of OFDM Signal in Presence of Nonlinear Ampliﬁcation with Memory Eﬀects

Aimer Y., Bouazza B. S., Bachir S., Duvanaud C.

Journal of Telecommunications and Information Technology

2018

nr 3

14--22

In OFDM systems, peak-to-average power ratio (PAPR) reduction of the signal is one of the main challenges that need to be overcome in order to use the transmitter in an eﬃcient manner. As one of attractive techniques, interleaving can be used in PAPR reduction for multicarrier signals without spectrum distortion. In this paper, the authors propose to extend the possibilities of interleaving to improve PAPR reduction, to use a new coding of interleaver keys at the transmitter and a robust decoding procedure at the receiver. In order not to degrade the data rate, the use of null subcarriers to transmit side information to the receiver is proposed and evaluated. Simulation results in the context of the WLAN 802.11a standard in the presence of a nonlinear power ampliﬁer model with memory, show a reduction of PAPR of approximately 5.2 dB, and an improvement of bit error rate and error vector magnitude of about 2 decades and 4% respectively, while respecting the spectral mask speciﬁcation.