The invention discloses a
photon terahertz communication
system based on differential
Delta-Sigma modulation and independent double single side bands, and belongs to the field of terahertz communication. The
system specifically comprises a transmitting end and a receiving end, a TX-DSP module of the transmitting end generates two paths of independent high-order
baseband signals by applying differential DSM and independent double
single side band technologies, drives an IQ modulator to modulate an input optical carrier, and obtains a terahertz
signal by using a
photon beat frequency method; the method comprises the following steps: transmitting a
QAM sequence to an RX-DSP module at a receiving end through a single-mode
optical fiber, carrying out
resampling and
digital down conversion to obtain two QPSK signals, respectively carrying out matched filtering, QPSK
digital signal processing, hard decision, differential DSM
demodulation and low-pass filtering to obtain two DMT signals, carrying out DMT
demodulation again, carrying out FFT by removing a
cyclic prefix, and converting a
time domain signal back to a
frequency domain to obtain an original
QAM sequence; and the
QAM sequence is demapped and recovered into an original
binary information sequence. According to the invention, high-order modulation is realized, and the
bit error rate performance is excellent.