PCM SIGNAL CODING

摘要

A signal having a non-uniform probability density is processed for transmission in pulse code modulated form. The signal is quantised using conventional methods and the quantised signal then coded using a non-sequential coding scheme in which binary codewords for the quantisation levels are chosen in accordance with the probability of the quantisation levels and number of ON bits in the codewords. Quantisation levels of higher probability are assigned codewords with few ON bits. An optical network embodying the present invention includes a central station1 having a master clock source 3. The central station1 is connected to a remote station 2 including signal processing means 6 arranged to process a signal for return transmission to the central station 1 by the method of the present invention.