| 摘要 |
<p>Quaternary modulation system for digital data transmission applied to a Quaternary Phase Shift Keying (QPSK) system that corresponds to the sum of two bi-phase carriers duly phase-shifted, adapted to the transmission of digital data previously subdivided into two binary signal trains, in which the spurious amplitude modulation is compensated for, at least in part, by altering the amplitude of that component of the quaternary phase carrier which does not change its state in correspondence with the phase transitions of the modulated signal.</p> |
