METHOD AND DEVICE FOR PHASE MODULATION OF A CARRIER WAVE AND APPLICATION TO THE DETECTION OF MULTI-LEVEL PHASE-ENCODED DIGITAL SIGNALS

摘要

The method for phase modulation of a carrier wave involves creating a set of signals sh(t) constituted by a wave of carrier frequency fc of which the phase φ(t) = hφ0(t) is modulated in time t such that sh(t) = cos(2πfct+ hφ0(t)), where h is an integer and where φ0(t) = 2arctan((t - t0)/w0). The modulation corresponds to a single-phase pulse centred at time t0 with positive characteristic duration w0 and incrementing the phase of the signal sh(t) by the quantity h2π, in such a way as to directly generate a single-sideband frequency spectrum. The carrier wave can be electromagnetic or acoustic. The method can be applied, in particular, to the transport of a piece of binary information by single sideband phase encoding, to the generation of orthogonal single-sideband signals, to the detection of multi-level phase-encoded digital signals having a single sideband, to the in-phase and out-of-phase transmission of phase-encoded binary signals having a single sideband, and to a mixed amplitude/phase single-sideband modulation.