Level regulator of the digital type

Claim 1

Level regulator for n frequency division multiplex transmission systems comprising n variable gain networks for adjusting the transmission level of said multiplex systems respectively, from the amplitudes of n pilot waves contained in said systems, a sampling device connected to said variable gain networks and rhythmed by a clock for sequentially sampling the multiplex systems downstream from said networks and delivering the samples concerning said n systems, in a time division multiplex form, an analog-digital converter for sending out digital values of the samples coming from the sampling device, digital filtering means having a narrow band and operating on a time sharing basis for said n systems for sending out, successively, at each sampling period in response to the n digital values of the samples of said n systems respectively, n digital values y1 to yn representing respectively the sampled amplitudes of the pilot waves extracted from the multiplex systems downstream from the networks, a calculation circuit receiving at each sampling period the values y1 to yn and operating on a time sharing basis for elaborating new values z1 to zn which are, respectively, function of the levels of the pilot waves downstream from the variable gain networks over a time interval of several sampling periods, a comparison element for comparing at each sampling period each of said values z1 to zn with a reference value and delivering as the results of these comparisons n values for the control of said n variable gain networks respectively, and a demultiplexing circuit connected to the output of said comparison element for applying said n values for the control to said n variable gain networks respectively.