Q. What do you mean by Companding?

In order to lower the crest factor of a waveform, so as to produce better performance, a process known as companding is used. It works like a compressor which progressively compresses the larger amplitudes of a message when it is passed through a nonlinear network. The inverse operation in the receiver is known as an expandor, when it restores the original message. Figure 15.3.4 illustrates a typical set of input-output characteristics for a formof compandor.One can see that the action of the compressor is to increase the rms-signal value for a given peak magnitude.