Enhancement of Power Efficiency in OFDM System by SLM with Predistortion Technique

Authors

  • Pankaj Kumar Sharma Motilal Nehru National Institute of Technology image/svg+xml
  • R. K. Nagaria Motilal Nehru National Institute of Technology image/svg+xml
  • T. N. Sharma Motilal Nehru National Institute of Technology image/svg+xml

DOI:

https://doi.org/10.26636/jtit.2011.4.1183

Keywords:

nonlinear HPA, OFDM, PAPR, SLM

Abstract

Orthogonal Frequency Division Multiplexing (OFDM) is considered as a strong candidate for future wireless communication because it is marked by its higher frequency multiplicity and greater immunity to multipath fading. However, the main drawback of OFDM is its high amplitude fluctuations measured by peak-to-average power ratio (PAPR), which leads to power inefficiency and requires expensive high power amplifier (HPA) with very good linearity. In this paper, we propose selected mapping (SLM) with predistortion technique to decrease the nonlinear distortion and to improve the power efficiency of the nonlinear HPA. In the proposed method SLM reduces the PAPR and improves the power efficiency, the predistorter improves the bit error rate (BER) performance of the system. The PAPR reduction is possible with SLM when compared with original OFDM. After reducing the PAPR with SLM the data goes into the HPA with and without predistorter. The BER performance curves of SLM method with or without predistorter shows that, predistorter operates more effectively in SLM method than original OFDM system. At 4 dB IBO (input backoff) the conventional method with predistorter achieves 1.8 dB SNR gain than conventional method without a predistorter and at 6 dB IBO the BER performance is towards the ideal linear amplifier. The proposed system will be evaluated for OFDM system in the presence of a nonlinear power amplifier.

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Published

2011-12-30

Issue

No. 4 (2011)

Section

RESEARCH ARTICLES

License

Copyright (c) 2023 Journal of Telecommunications and Information Technology

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

[1]
P. K. Sharma, R. K. Nagaria, and T. N. Sharma, “Enhancement of Power Efficiency in OFDM System by SLM with Predistortion Technique”, JTIT, vol. 46, no. 4, pp. 86–91, Dec. 2011, doi: 10.26636/jtit.2011.4.1183.