[18.] Yuan Jiang, "New companding
transform for PAPR reduction in OFDM", IEEE Commun Letters, vol.14, no.4, pp.
For the coefficient z satisfying [absolute value of z] [greater than or equal to] T(p, q), the companding
error e between z and z' is given by
Fig.4 CCDF for DWT/DCT with 64DAPSK/64QAM for no companding
and exponential signals In figure 4, the continuous line graphs represent the complementary cumulative distribution (CCDF) vs.
The efficiency of the proposed algorithm is compared to the scalar companding
system based on the G.711 standard .
This unit is called companding
transform (CT), which will be addressed in the next section in detail.
schemes offer the advantages of low implementation complexity and capability of efficiently trading between PAPR and BER.
The aim of this study is to gain the advantages of KHN circuit structure, log-domain characteristics and companding
idea listed above.
On the other hand, clipping and companding
are low in complexity but cause significant signal distortion, that results in degraded error performance and spectral regrowth.
Motorised Unit,Sampling & Reconstruction ,Delta, Adaptive Delta and Delta Sigma Modulation/ Demodulation ,Data Formatting and Carrier Modulation/ Transmitter ,Data Reformatting & Carrier Demodulation Receiver,Error Detection and Correction-Cyclic Code,PCM Generation & Demodulation using CODEC Chip,4-Channel TDM-PCM Transmitter and Receiver,Digital Companding
A-Law and o-Law,Understanding Noise Generator and its applications,PAM, PPM, PWM and Line
determining the codebook, is often based on companding
technique by which non-uniform quantization is achieved by compression of the input signal x using a compressor with a non-linear characteristic c(*), then by the quantization of the compressed signal c(x) applying uniform quantizer and finally by expanding the quantized values of the compressed signal using a non-linear inverse compression characteristics [c.sup.-1](*).
The signal distortion algorithm limits the OFDM signal below a given threshold by nonlinear distortion and includes: signal clipping  and companding
In (9)-(10) parameter tmax denotes the maximal amplitude of the optimal companding
quantizer for the unit variance and its values, depending on the number of quantization levels, can be find in .