Enhancing PAPR performance of MIMO-OFDM systems using SLM technique with centering phase sequence matrix

Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO OFDM) is a key technology for contemporary communication systems due to its spectral efficiency, higher data rates, better diversity gain, good link reliability and both inter symbol interference (ISI) and multipath fading free transmission. However, due to the presence of OFDM, MIMO-OFDM suffers from high peak to average power ratio (PAPR). Even though, several schemes are available to mitigate PAPR, there is no standard solution. Selective Mapping (SLM) significantly reduces the PAPR in OFDM systems at the cost of computational complexity (CC). The CC of SLM can be reduced by proper design of SLM. This paper considers a low complexity SLM (LC SLM) scheme in which both the CC and length of the index of selected phase sequence are significantly reduced. The PAPR of an SLM-OFDM depends on the number of subcarriers in OFDM, the number of candidate blocks in SLM and selected phase sequence and this paper investigate various phase sequences and analyses their PAPR performance. Simulation results show the superior performance of Riemann sequence over the other phase sequences.

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Factors Influencing the PAPR Performance of OFDM and MIMO-OFDM Systems

International Journal of Interdisciplinary Telecommunications and Networking ◽

10.4018/ijitn.2019070103 ◽

2019 ◽

Vol 11 (3) ◽

pp. 23-33 ◽

Cited By ~ 1

Author(s):

Tahreer Mahmood ◽

Seshadri Mohan

Keyword(s):

Orthogonal Frequency Division Multiplexing ◽

Multiple Input Multiple Output ◽

Average Power ◽

Channel Fading ◽

Ofdm Systems ◽

Practical Applications ◽

Factors Influencing ◽

Mimo Ofdm ◽

Modulation Schemes ◽

Papr Performance

Multiple-input multiple-output technology together with orthogonal frequency division multiplexing (MIMO-OFDM) is an effective technique to combat multi-channel fading and to improve bandwidth efficiency. Simultaneously, it also increases the system's ability to provide reliable transmission. However, the main disadvantage of OFDM is the high peak-to-average-power ratio (PAPR), which, if not mitigated, will negatively impact practical applications. The high PAPR increases complexity and Bit Error Rate. In this research, the authors investigate the factors influencing the PAPR performance of both OFDM and MIMO-OFDM systems. The objective of this research is to make researchers in this field become familiar with this problem as well as to impart an understanding of the factors that influence PAPR. In this study, the authors classify the factors that impact PAPR into modulation schemes and a number of sub-carriers. These parameters influence the PAPR performance have been analyzed and simulated by using MATLAB. It is observed that the numbers of sub-carriers have a great effect on the PAPR performance. However, modulation schemes can have a small effect on PAPR performance.

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