Patent ID: 6163230
Filing Date: 2000-12-19
Classification: H03C,H04L

Abstract:
An electronic phase-shift keying modulator circuit comprising an input (1) intended to receive a sinusoidal input signal Se of angular frequency .omega.e and an output (2) delivering a sinusoidal output signal Ss phase shifted with respect to the input signal by a value .phi.j which can vary among m values, .phi.1, . . . , .phi.j, . . . , .phi.m, m being an integer greater than or equal to 2, in accordance with a control signal SCj, the output signal Ss having an angular frequency .omega.s that is independent of the control signal Scj, wherein said circuit comprises:a distribution line (6) extending from the input and including n cells Co, . . . , Ci, . . . , Cn-1, of similar phase shift, n being a whole number greater than or equal to 2, the n phase-shift cells being mounted along the distribution line (6) with each phase-shift cell Ci of rank i along the distribution line (6) comprising:an input, referred to as the series input ISi, receiving the signal coming from the input of the circuit, either directly where i=0, or via (i-1) preceding phase-shift cells of rank less than i, interposed between the input (1) of the circuit and this phase-shift cell Ci,a first output, referred to as the series output OSi, delivering the signal on the distribution line to a subsequent phase-shift cell Ci+1 of higher rank i+1, or, where i=n-1, to a terminating device (7) of the distribution line (6),a tapping point Ni of the distribution line (6),a second output, referred to as the branched output ODi, connected to the tapping point Ni via a transistor Ti whose first terminal is connected to the tapping point Ni, whose second terminal is connected to ground, and whose third terminal supplies said branched output ODi of the phase-shift cell Ci, each phase-shift cell Ci being designed to deliver at its branched output ODi a signal SDi that is phase shifted with respect to the input signal Se, by the sum .phi.(Ci) of the phase shifts successively applied to the input signal Se, from the input (1) of the circuit by the phase-shift cells interposed between the input (1) of the circuit and said branched output ODi,connected to said branched output ODi of each phase-shift cell Ci, a switching/modulating circuit controlled by the control signal SCj, this switching/modulating circuit being:when n=m, a switching circuit (CO0, CO1) delivering either a zero signal, or the signal SDi received from the cell Ci, in accordance with the control signal SCj,when n.noteq.m, a modulating circuit Mo, . . . , Mi, . . . , Mn-1 with p phase states, p being a whole number less than m chosen so that m.ltoreq.p.sup.n, designed to phase-shift the signal SDi received from the phase-shift cell Ci by a value .phi.k, k being a whole number varying between 1 and p, in accordance with the control signal SCj,means (5) for summing in phase the signals Ssi coming from n switching/modulating circuits and to deliver at said output (2) of the circuit the result of this sum which forms the output signal Ss.