Predistorders#

class Hard_Clipper(cr_dB: float, name: str = 'hard_clipping')#

Implements a hard clipping method to reduce the Peak-to-Average Power Ratio (PAPR) of a signal.

The Hard_Clipper class is designed to apply a hard clipping technique to a signal, which reduces its PAPR. Hard clipping limits the amplitude of the signal to a certain threshold, reducing the peaks of the signal while keeping the average power relatively unchanged.

Attributes#

cr_dBfloat

Clipping ratio in decibels (dB). Determines the threshold for clipping.

namestr

Name of the processor.

Reference#

  • [1] Y. Rahmatallah et S. Mohan, « Peak-To-Average Power Ratio Reduction in OFDM Systems: A Survey And Taxonomy », IEEE Commun. Surv. Tutorials, vol. 15, no 4, p. 1567 1592, 2013, doi: 10.1109/SURV.2013.021313.00164.

class ICT_PAPR_Reductor(PAPR_max_dB: float, filter_weight: float, N_it: int = 16, shift: bool = False, axis: int = 0, norm: str = 'ortho', name: str = 'ICT')#

Implements the Iterative Clipping and Filtering (ICT) method for Peak-to-Average Power Ratio (PAPR) reduction in OFDM signals.

The ICT_PAPR_Reductor class is designed to reduce the PAPR of an Orthogonal Frequency Division Multiplexing (OFDM) signal using the ICT method. This method involves iteratively clipping and filtering the signal to achieve a target PAPR level.

Attributes#

PAPR_max_dBfloat

Target maximum PAPR in decibels (dB).

filter_weightfloat

Weighting factor applied during the filtering step.

N_itint

Number of iterations for the clipping and filtering process. Default is 16.

shiftbool

Whether to apply an inverse FFT shift to the processed signal. Default is True.

normstr

Normalization mode for FFT and IFFT operations. Default is “ortho”.

namestr

Name of the processor. Default is “ICT”.

Reference#

  • [1] Wang, Y-C., and Z-Q. Luo. “Optimized iterative clipping and filtering for PAPR reduction of OFDM signals.” IEEE Transactions on communications 59.1 (2010): 33-37.

class PTS_PAPR_Reductor(phase_alphabet: None, N_sub: int = 16, name: str = 'PTS')#

Implements the Partial Transmit Sequences (PTS) method for Peak-to-Average Power Ratio (PAPR) reduction in OFDM signals.

The PTS_PAPR_Reductor class is designed to reduce the PAPR of an Orthogonal Frequency Division Multiplexing (OFDM) signal. It employs the PTS method, which involves dividing the signal into sub-blocks, applying different phase factors to each block, and then selecting the combination of phase factors that minimizes the PAPR.

Attributes#

phase_alphabetlist

List of phase factors to be used in the PTS method.

N_subint

Number of sub-blocks the OFDM signal is divided into.

namestr

Name of the processor. Default is “PTS”.

Reference#

  • [1] L. J. Cimini and N. R. Sollenberger, “Peak-to-average power ratio reduction of an OFDM signal using partial transmit sequences,” 1999 IEEE International Conference on Communications (Cat. No. 99CH36311), Vancouver, BC, Canada, 1999, pp. 511-515 vol.1, doi: 10.1109/ICC.1999.767992.