The final element of this
companding technique, expander, uses inverse compression function [c.sup.-1](x).
Chung, "PAPR reduced OFDM visible light communication using exponential nonlinear
companding," in Proceedings of the 2013 IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems, COMCAS '13, pp.
Sharaiha, "Performance improvement of a SOA-based coherent optical-OFDM transmission system via nonlinear
companding transforms," Optics Communications, vol.
Companding is another effective distortion based PAPR reduction technique in the OFDM system [18].
Companding is applied to the left-right signal (the stereo difference) and to second audio program signals.
adopted the
companding technology on Integer Wavelet Transform (IWT) coefficients to develop a reversible watermarking algorithm.
Several solutions were suggested by researchers to minimize the probability of occurrence of large PAPR in OFDM signals including Clipping and filtering method (Armstrong 2002), SLM (Bauml et al., 1996), PTS (Muller and Huber, 1997),
Companding Scheme (Huang et al., 2004) and certain time domain methods.
The PSD of the DWT and DCT OFDM systems were also simulated with and without [mu] -law
companding, and exponential transforms.
G.711 is the
companding system employing the piecewise linear approximation to the, [micro]-law or the A-law logarithmic compression function.
The other group processes the MCM signals directly, such as clipping [12]-[14] and
companding transform [15]-[19].
Psychalinos, "0.5-V fractional-order
companding filters", International Journal of Circuit Theory and Applications, vol.