Abstract: A device for the transmission of synchronous information by an asynchronous network, notably an ATM type network, where information elements are conveyed by packets of data bits between a transmitter unit and a receiver unit. Each of these packets is formed by an information cell comprising a header carrying an address and a useful field bearing the information to be transmitted. The transmitter unit and the receiver unit work with each other in a synchronous mode on the basis of respective plesiochronous local clocks. The device detects and compensates for a lengthy fading of transmission of the flow of information cells received by the receiver unit. The device also detects and compensates for a loss or insertion of cells in the flow of information cells received by the receiver organ.

Abstract: A process for the demodulation of an amplitude modulated signal composed of two suppressed carriers, at a same frequency F and in phase quadrature, which are respectively modulated by two modulation signals, the modulated signal being preceded by a reference signal at frequency F, bysampling the reference signal and the modulated signal, according to a frequency m.F (m being an integer);determining a polar angle .psi..sub.t of a rotating vector representing the reference signal, at time t, by calculating: ##EQU1## where x(t) and x(t-(1/4F)) are the values of two successive samples of the reference signal;determining polar coordinates (.rho..sub.t, .theta..sub.t) of a rotating vector representing the modulated signal, at time t, by calculating: ##EQU2## where y(t) and y(t-(1/4F)) are values of two successive samples of the modulated signal,calculating .gamma.=.theta..sub.t -.omega..sub.t -.phi..sub.o, where .phi..sub.o is the phase displacement between the reference signal and one of the carriers,calculating .