| 摘要 |
The invention relates to a process and a device carrying out this process which makes it possible to increase simultaneously the signal/noise ratio and the data transmission speed. The process is based on phase-locking: psi m = pi /2 + m2 pi or phase locking: psi <1>m = 3/2 pi + m2 pi the carrier sinusoid, in the presence of the binary pulse whose duration is equal to an integer number of periods of the said sinusoid. The spectrum of the modulated signal is limited to the frequency of the carrier. The modulator consists of the synthesiser 3 of the digital sinusoid and of the synchronisation circuit 2 which halts the operation of the synthesiser 3 once a pulse is present at the input of the interface 1. The amplifier 6 converts the one-way variations in the sinusoid into two-way alternations. The summing unit 7, the integrator 8 and the comparator 9 render the modulator signal symmetrical with respect to zero volts. The process and the modulator according to the invention are particularly intended for the transmission of data in any telecommunications trunk. <IMAGE>
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