Abstract:
Embodiments of the present disclosure provide a signal processing method, an apparatus, and a system. The signal processing method includes acquiring a phase of each of transmit antennas when the lth OFDM data symbol is sent, and acquiring a phase of each of receive antennas when the lth OFDM data symbol is received. The method further includes compensating received signals of each of the receive antennas according to the phase of each of the transmit antennas when the lth OFDM data symbol is sent and the phase of each of the receive antennas when the lth OFDM data symbol is received, to obtain compensated signals of each receive antenna.
Abstract:
Embodiments of the present invention provide a frame synchronization method and apparatus, which can reduce impact of a carrier frequency offset. In those embodiment, a solution is provided and the solution includes: obtaining a received signal of a receiving antenna; calculating an auto-correlation value of the received signal and determining a time corresponding to the auto-correlation value that is of the received signal and that meets a first preset condition, as an initial estimation time; obtaining a carrier frequency offset estimation value according to the initial estimation time, the received signal, and a frequency offset estimation algorithm, and performing frequency offset compensation on the received signal by using the carrier frequency offset estimation value; calculating a cross-correlation value and an auto-correlation value of the received signal on which the frequency offset compensation has been performed. The embodiments of the present invention are used for frame synchronization.
Abstract:
Embodiments of the present invention provide a method for signal compensation. The method includes: receiving, by a receiver via N receiving antennas, a plurality of channel estimation preamble signals sent by M transmitting antennas of a remote transmitter, wherein the plurality of channel estimation preamble signals contain measurement signals of the M transmitting antennas; determining, by the receiver, channel estimation parameters and channel phase shift parameters according to the measurement signals of the M transmitting antennas of the remote transmitter; and determining, by the receiver, signal compensation according to the channel estimation parameters and the channel phase shift parameters. According to the method for signal compensation and the multiple-input multiple-output orthogonal frequency division multiplexing communication system provided by the embodiments of the present invention, accuracy of an estimated value of transmitted data is improved.
Abstract:
The present invention provides a signal demodulation method and device. The method includes: obtaining a symbol probability parameter, where the symbol probability parameter comprises: an amplitude ry and a phase angle φy of a receive signal, an amplitude rxj and a phase angle φxj of each constellation point xj in a decision constellation point set, and a standard deviation σn of Gaussian noise and a standard deviation πθ of phase noise; calculating, according to the symbol probability parameter, a symbol probability that a transmit signal is each constellation point xj in the decision constellation point set; and performing demodulation according to the symbol probability, and outputting demodulation information. The present invention improves an anti-phase-noise capability.
Abstract:
A transmitting circuit, a transceiver, a communication system, and a method for transmitting data. The transmitting circuit includes a digital interface circuit configured to obtain, in a predetermined bandwidth, data to be sent, and decompose the data into N parallel sub digital signal flows; a digital modulation circuit configured to modulate the N sub digital signal flows to obtain N modulated signals; a frequency relocation circuit configured to perform frequency relocation on the N modulated signals; a synthesizer configured to modulate M modulated signals of the N modulated signals that have undergone frequency relocation into a bandwidth signal; a digital to analog converter configured to receive the bandwidth signal, and perform digital to analog conversion on the bandwidth signal to obtain an analog signal; an up-conversion circuit configured to receive the analog signal, and convert the analog signal into a radio frequency signal.
Abstract:
Embodiments of this application provide a modulation method and apparatus. The method includes: receiving a code word sequence, where each code word includes N bits, and the code word sequence includes at least a first code word; mapping the code word sequence into M sequences, where each sequence includes N/M bits from the first code word; mapping the M sequences into a symbol sequence, where each symbol is corresponding to M bits, the M bits are respectively from the M sequences, first bits corresponding to N/M first-type symbols are from the first code word, and second bits corresponding to N/M second-type symbols are from the first code word. Thus a signal-to-noise ratio requirement during higher order modulation lowered.
Abstract:
Embodiments of this application provide a modulation method and apparatus. The method includes: receiving a code word sequence, where each code word includes N bits, and the code word sequence includes at least a first code word; mapping the code word sequence into M sequences, where each sequence includes N/M bits from the first code word; mapping the M sequences into a symbol sequence, where each symbol is corresponding to M bits, the M bits are respectively from the M sequences, first bits corresponding to N/M first-type symbols are from the first code word, and second bits corresponding to N/M second-type symbols are from the first code word. Thus a signal-to-noise ratio requirement during higher order modulation lowered.
Abstract:
A transmitting circuit, a transceiver, a communication system, and a method for transmitting data. The transmitting circuit includes a digital interface circuit configured to obtain, in a predetermined bandwidth, data to be sent, and decompose the data into N parallel sub digital signal flows; a digital modulation circuit configured to modulate the N sub digital signal flows to obtain N modulated signals; a frequency relocation circuit configured to perform frequency relocation on the N modulated signals; a synthesizer configured to modulate M modulated signals of the N modulated signals that have undergone frequency relocation into a bandwidth signal; a digital to analog converter configured to receive the bandwidth signal, and perform digital to analog conversion on the bandwidth signal to obtain an analog signal; an up-conversion circuit configured to receive the analog signal, and convert the analog signal into a radio frequency signal.
Abstract:
Embodiments of the present disclosure provide a signal processing method, an apparatus, and a system. The signal processing method includes acquiring a phase of each of transmit antennas when the lth OFDM data symbol is sent, and acquiring a phase of each of receive antennas when the lth OFDM data symbol is received. The method further includes compensating received signals of each of the receive antennas according to the phase of each of the transmit antennas when the lth OFDM data symbol is sent and the phase of each of the receive antennas when the lth OFDM data symbol is received, to obtain compensated signals of each receive antenna.