Abstract: A communication method, a communications apparatus, and a storage medium are disclosed, to reduce a probability that consecutive bit errors occur in a communications system. A received to-be-sent signal is modulated to obtain a modulated signal, and N rounds of operations are further performed on the modulated signal to obtain an encoded signal. An output of the 1st-round operation in the N rounds of operations is determined based on the modulated signal and an output that is of the Nth-round operation and that is processed by a first delay circuit, and an output of the ith-round operation in the N rounds of operations is determined based on an output of the (i?1)th-round operation and an output that is of the Nth-round operation and that is processed by a second delay circuit, where i is an integer greater than 1 and less than or equal to N.

Abstract: A signal generation method and an electronic device pertain to the field of communications technologies, and include normalizing an I path of four-level signals and a Q path of four-level signals to obtain a normalized I path of four-level signals and a normalized Q path of four-level signals, mapping the normalized I path of four-level signals and the normalized Q path of four-level signals based on a normalization coefficient to obtain two paths of six-level signals, and driving a dual-drive Mach-Zehnder modulator (DDMZM) based on the six-level signals.

Abstract: This disclosure provides a signal generation method and an electronic device, and pertains to the field of communications technologies. A mapping process is increased in this disclosure, to convert a four-level signal into a six-level signal, so that a dual-drive Mach-Zehnder modulator DDMZM is driven based on the six-level signal, thereby reducing a signal-to-noise ratio requirement of an input signal, improving a noise resistance capability of a transmit end, reducing impact from crosstalk between signals, and reducing a requirement standard on components such as a DAC and a driver. In addition, in embodiments of this disclosure, an amplitude requirement of a drive signal is greatly reduced, so that the amplitude requirement of the drive signal is reduced, and a power consumption requirement is further reduced, thereby reducing working pressure of the DDMZM, and improving overall system performance.

Abstract: A communication method, a communications apparatus, and a storage medium are disclosed, to reduce a probability that consecutive bit errors occur in a communications system. A received to-be-sent signal is modulated to obtain a modulated signal, and N rounds of operations are further performed on the modulated signal to obtain an encoded signal. An output of the 1st-round operation in the N rounds of operations is determined based on the modulated signal and an output that is of the Nth-round operation and that is processed by a first delay circuit, and an output of the ith-round operation in the N rounds of operations is determined based on an output of the (i?1)th-round operation and an output that is of the Nth-round operation and that is processed by a second delay circuit, where i is an integer greater than 1 and less than or equal to N.

Abstract: Embodiments of the present disclosure disclose a signal modulation and demodulation method and system, and an apparatus, to eliminate SSBI generated in a modulation and demodulation method. The method includes: performing, by a transmit end, PAM encoding on an input signal to obtain a PAM signal; electrically modulating, by the transmit end, the PAM signal by using a first filter; converting, by the transmit end, the electrically modulated PAM signal into an analog signal; optically modulating, by the transmit end, the analog signal by using an electro-optic modulator to obtain an optical signal, and sending the optical signal. Another method includes receiving, by a receive end, the optical signal, and converting the optical signal into an electrical signal; electrically demodulating, by the receive end, the electrical signal by using a second filter; and performing PAM decoding, by the receive end, the electrically demodulated electrical signal to obtain a restored input signal.

Abstract: An optical signal processing method and a coherent receiver, wherein an in-phase signal XI in a first polarization direction and an in-phase signal YI in a second polarization direction are added up to obtain a signal I; a quadrature signal XQ in the first polarization direction and a quadrature signal YQ in the second polarization direction are added up to obtain a signal Q; and quantization, combination, and digital signal processing are performed on the I and the Q. After summation, two signals need to be quantized. Therefore, a quantity of ADCs is reduced by half. In addition, because power consumption of a summation component is less than that of an ADS, power consumption of optical signal processing can be reduced. In addition, because there is a preset value, the summation may be performed after phase-inversion is performed on one analog signal, thereby avoiding a signal loss caused by the summation.

Abstract: The present invention discloses a digital signal processor, including: a signal generation unit, configured to generate a first digital signal and a second digital signal; a first modulation unit, configured to modulate the first digital signal to obtain a third digital signal; a second modulation unit, configured to modulate the second digital signal to obtain a fourth digital signal; a first phase shifting unit, configured to perform phase shifting on the third digital signal, to output the third digital signal and a fifth digital signal; a second phase shifting unit, configured to perform phase shifting on the fourth digital signal, to output the fourth digital signal and a sixth digital signal; an adder, configured to calculate a sum of the third digital signal and the fourth digital signal, to obtain a seventh digital signal; and a subtractor, configured to subtract the sixth digital signal from the fifth digital signal.

Abstract: Embodiments of the present disclosure disclose a signal modulation and demodulation method and system, and an apparatus, to eliminate SSBI generated in a modulation and demodulation method. The method includes: performing, by a transmit end, PAM encoding on an input signal to obtain a PAM signal; electrically modulating, by the transmit end, the PAM signal by using a first filter; converting, by the transmit end, the electrically modulated PAM signal into an analog signal; optically modulating, by the transmit end, the analog signal by using an electro-optic modulator to obtain an optical signal, and sending the optical signal. Another method includes receiving, by a receive end, the optical signal, and converting the optical signal into an electrical signal; electrically demodulating, by the receive end, the electrical signal by using a second filter; and performing PAM decoding, by the receive end, the electrically demodulated electrical signal to obtain a restored input signal.

Abstract: An optical signal processing method and a coherent receiver, wherein an in-phase signal XI in a first polarization direction and an in-phase signal YI in a second polarization direction are added up to obtain a signal I; a quadrature signal XQ in the first polarization direction and a quadrature signal YQ in the second polarization direction are added up to obtain a signal Q; and quantization, combination, and digital signal processing are performed on the I and the Q. After summation, two signals need to be quantized. Therefore, a quantity of ADCs is reduced by half. In addition, because power consumption of a summation component is less than that of an ADS, power consumption of optical signal processing can be reduced. In addition, because there is a preset value, the summation may be performed after phase-inversion is performed on one analog signal, thereby avoiding a signal loss caused by the summation.

Abstract: The present invention discloses a signal modulation method, including: demultiplexing an input signal into 2N sub-signals; grouping every two of the 2N sub-signals into a pair; performing filtering on two sub-signals in each pair; performing carrierless amplitude phase (CAP) modulation on the two sub-signals in each pair; modulating the two sub-signals in each pair to a same frequency band, to generate N pairs of CAP signals, where frequency bands of different pairs of sub-signals are different, and a spacing between center frequencies of two neighboring frequency bands is greater than or equal to an average value of baud rates of sub-signals corresponding to the two neighboring frequency bands; and combining the N pairs of CAP signals, and performing electro-optic modulation on a signal obtained after the combining. A signal demodulation method corresponding to the signal modulation method is further disclosed.

Abstract: The present invention discloses a digital signal processor, including: a signal generation unit, configured to generate a first digital signal and a second digital signal; a first modulation unit, configured to modulate the first digital signal to obtain a third digital signal; a second modulation unit, configured to modulate the second digital signal to obtain a fourth digital signal; a first phase shifting unit, configured to perform phase shifting on the third digital signal, to output the third digital signal and a fifth digital signal; a second phase shifting unit, configured to perform phase shifting on the fourth digital signal, to output the fourth digital signal and a sixth digital signal; an adder, configured to calculate a sum of the third digital signal and the fourth digital signal, to obtain a seventh digital signal; and a subtractor, configured to subtract the sixth digital signal from the fifth digital signal.

Abstract: The present invention discloses a signal modulation method, including: demultiplexing an input signal into 2N sub-signals; grouping every two of the 2N sub-signals into a pair; performing filtering on two sub-signals in each pair; performing carrierless amplitude phase (CAP) modulation on the two sub-signals in each pair; modulating the two sub-signals in each pair to a same frequency band, to generate N pairs of CAP signals, where frequency bands of different pairs of sub-signals are different, and a spacing between center frequencies of two neighboring frequency bands is greater than or equal to an average value of baud rates of sub-signals corresponding to the two neighboring frequency bands; and combining the N pairs of CAP signals, and performing electro-optic modulation on a signal obtained after the combining. A signal demodulation method corresponding to the signal modulation method is further disclosed.