PAPR reduction for FBMC/OQAM using hybrid scheme of different Precoding transform and mu-law companding

Abstract

The filter banks multicarrier with offset quadrature amplitude modulation (FBMC/OQAM) is developing multicarrier modulation technique used in the next wireless communication system (5G). FBMC/OQAM supports high data rate and high band width efficiency. However, one of the major drawbacks of FBMC system is high peak to Average Power Ratio (PAPR) of the transmitted signal, which causes serious degradation in performance of the system. Therefore, it is required to use a proper PAPR scheme at the transmitter to reduce the PAPR. In this paper, a hybrid scheme is investigated with the combination of preceding transform technique and Mu Law Companding technique to reduce PAPR in FBMC systems. Moreover, four preceding techniques are examined to find the best Precoding technique which can be used with Mu law commanding. We assessed the discrete Hartley transform (DHT). The discrete cosine transformed (DCT), the Discrete Sine Transform (DST), and the Walsh Hadamard transforms (WHT) which are applied separately with Mu Companding. The numerical results verify that the FBMC systems with all Precoding technique combined with Mu law commanding can improve PAPR performance of the signals greatly with the best results achieved when the combination scheme consists of the DST Precoding and Mu law commanding for both PAPR and BER performance.

A Novel Hybrid Precoding-Companding Technique for Peak-to-Average Power Ratio Reduction in 5G and beyond

“…The authors in [ 30 ] showed that DST- is better than the WHT- , DHT- , and DCT- from the PAPR reduction point of view. The model in [ 30 ] considered only the AWGN channel and neglected HPA. The authors in [ 31 ] introduced DST-A without any comparison with the previous precoding-companding techniques.…”

“…The limitations of the discussed works are summarized as follows: The authors in [ 22 , 24 , 27 , 28 , 30 , 32 , 33 , 34 , 36 , 37 ] hybridized -law with different precoding matrices due to its high PAPR reduction gain. However, BER and OOB radiation are more important metrics than PAPR reduction gain when working with PAPR reduction techniques that cause BER degradation, such as companding techniques.…”

“… Many precoding-companding techniques [ 26 , 29 , 31 , 36 , 37 ], are not compared with any previous works. HPA was neglected in the models [ 22 , 26 , 27 , 28 , 30 , 31 , 33 , 34 , 35 , 36 , 37 ], although HPA is the source of nonlinear distortion. The authors in [ 22 , 26 , 28 , 30 , 31 , 34 , 36 , 37 ] have not considered Rayleigh channel.…”

“…HPA was neglected in the models [ 22 , 26 , 27 , 28 , 30 , 31 , 33 , 34 , 35 , 36 , 37 ], although HPA is the source of nonlinear distortion.…”

“…The authors in [ 22 , 26 , 28 , 30 , 31 , 34 , 36 , 37 ] have not considered Rayleigh channel. However, OFDM was designed originally for Rayleigh channels.…”