Abstract: A device and a method for receiving a differential quadrature phase shift keying (DQPSK) signal and a method for obtaining a DQPSK signal are provided. The device includes: a splitter, configured to split the DQPSK signal to obtain two optical signals; two optical bandpass filters, connected to the splitter and configured to optically bandpass filter the two optical signals respectively, in which the two optical bandpass filters respectively have a positive frequency offset and a negative frequency offset from a central frequency of the DQPSK signal received by the splitter; and two photoelectric detectors, correspondingly connected to the two optical bandpass filters and configured to photoelectrically convert the filtered optical signals to obtain data signals.

Abstract: In the field of communication and transmission, a method and a device for receiving an OPFDM-DQPSK signal are provided. The device includes a power splitter, adapted to split the OPFDM-DQPSK signal into two beams of signals; a polarization beam splitter (PBS), adapted to splitting one of the two beams of signals into a first signal and a second signal; a demultiplexer (Demux), adapted to demultiplex the other beam of signal to obtain a third signal and a fourth signal; two delayers, adapted to delay the third signal and the fourth signal respectively; a first frequency-mixing receiving module, adapted to perform frequency-mixing receiving on the first signal and the delayed third signal; a second frequency-mixing receiving module, adapted to perform frequency-mixing receiving on the second signal and the delayed fourth signal; and a decision recovery module, adapted to recover four logical sequences by performing decision on the four electrical signals.

Abstract: A differential quadrature phase shift keying (DQPSK) system, method, and device are disclosed. The DQPSK system includes: a transmitter, configured to: pre-code an input first signal and second signal, and generate an in-phase signal and a quadrature signal; modulate the in-phase signal to generate a first differential phase shift keying (DPSK) signal, and modulate the quadrature signal to generate a second DPSK signal; perform a 90 degree phase shift on the first DPSK signal or the second DPSK signal, and interfere with the other DPSK signal to obtain a DQPSK signal; and send the DQPSK signal to a receiver; the receiver, configured to: demodulate the DQPSK signal sent from the transmitter in detuned filter mode, and restore the first signal and the second signal through optical/electrical (o/E) conversion.

Abstract: A device and a method for receiving a differential quadrature phase shift keying (DQPSK) signal and a method for obtaining a DQPSK signal are provided. The device includes: a splitter, configured to split the DQPSK signal to obtain two optical signals; two optical bandpass filters, connected to the splitter and configured to optically bandpass filter the two optical signals respectively, in which the two optical bandpass filters respectively have a positive frequency offset and a negative frequency offset from a central frequency of the DQPSK signal received by the splitter; and two photoelectric detectors, correspondingly connected to the two optical bandpass filters and configured to photoelectrically convert the filtered optical signals to obtain data signals.

Abstract: In the field of communication and transmission, a method and a device for receiving an OPFDM-DQPSK signal are provided. The device includes a power splitter, adapted to split the OPFDM-DQPSK signal into two beams of signals; a polarization beam splitter (PBS), adapted to splitting one of the two beams of signals into a first signal and a second signal; a demultiplexer (Demux), adapted to demultiplex the other beam of signal to obtain a third signal and a fourth signal; two delayers, adapted to delay the third signal and the fourth signal respectively; a first frequency-mixing receiving module, adapted to perform frequency-mixing receiving on the first signal and the delayed third signal; a second frequency-mixing receiving module, adapted to perform frequency-mixing receiving on the second signal and the delayed fourth signal; and a decision recovery module, adapted to recover four logical sequences by performing decision on the four electrical signals.