| 摘要 |
The invention discloses an apparatus for code modulating digital signal. The appartus can tridimensionally code modulate the digital signal which needs to transmit, it comprises: characteristic fundamental wave frequency controller fi(t), characteristic fundamental wave waveform controller Zm, characteristic fundamental wave amplitude controller Vr(t), frequency and waveform controlled fundamental wave generator, D/A converter and buffering-gain controlled amplifier. In which, under controlling of characteristic fundamental wave frequency controller f(t) and characteristic fundamental wave waveform controller Zm, the frequency and waveform controlled fundamental wave generator generates frequency-modulation and waveform modulation(modulating waveform) signal Zm,f = Pi Zm {2Pif i (t)}. Then by using the D/A converter, the frequency and waveform controlled fundamental wave generator converts the digital signal expressed by frequency-modulation and waveform-modulation(modulating-waveform) signal Zm,f into analog signal. At last under controlling of characteristic fundamental wave amplitude controller Vr(t), the buffering-gain controlled amplifier amplitude modulates the analog signal Zm,f outputted by D/A converter so as to form modulated characteristic fundamental-wave signal output. In addition, the invention also discloses a method for code modulating the digital signal.
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