Patent classifications
H04L27/148
Receiver with frequency deviation detection capability and method therefor
A receiver includes an analog receiver and a digital processor. The analog receiver has an input for receiving a radio frequency (RF) signal, and an output for providing a digital intermediate frequency signal. The digital processor has an input for receiving the digital intermediate frequency signal, and an output for providing digital symbols. The digital processor measures peak-to-peak frequency deviation of the digital intermediate frequency signal, and performs a digital signal processing function on the digital intermediate frequency signal to provide the digital symbols based on the peak-to-peak frequency deviation so measured.
Circuit and method for compensating frequency offset in wireless frequency shift keying communication
Disclosed are a circuit and method for compensating frequency offset in wireless frequency shift keying communication, and belongs to the field of wireless communication technologies. The circuit includes an analog-to-digital converter, a first decimating module, a digital down-converter, a second decimating module, a frequency offset estimator, a frequency shift keying demodulator, a timing recovery module, a synchronization header detector, a frequency recovery module, a numerical-control oscillator, and a differential decoding and symbol decision module. A rough frequency offset estimation value is combined with a slicer error to generate a control signal related to frequency offset in a received signal, and the control signal is transmitted to the numerical-control oscillator to adaptively adjust a center frequency of an oscillated signal.
Circuit and method for compensating frequency offset in wireless frequency shift keying communication
Disclosed are a circuit and method for compensating frequency offset in wireless frequency shift keying communication, and belongs to the field of wireless communication technologies. The circuit includes an analog-to-digital converter, a first decimating module, a digital down-converter, a second decimating module, a frequency offset estimator, a frequency shift keying demodulator, a timing recovery module, a synchronization header detector, a frequency recovery module, a numerical-control oscillator, and a differential decoding and symbol decision module. A rough frequency offset estimation value is combined with a slicer error to generate a control signal related to frequency offset in a received signal, and the control signal is transmitted to the numerical-control oscillator to adaptively adjust a center frequency of an oscillated signal.
Transmit pre-coding
A method for receiving an Orthogonal Frequency Division Multiplexing (OFDM) signal transmitted by a user device in a wireless network comprises determining which subcarrier frequencies are allocated to the user device; converting the OFDM signal to a frequency-domain values corresponding to the subcarrier frequencies; and decoding the frequency-domain values to recover data symbols encoded by the user device on the subcarrier frequencies. The decoding employs codes that are inverse to, complex-conjugate of, or complementary to a set of complex-valued codes employed by the user device to shape the OFDM signal into a superposition of cyclic-shifted pulse waveforms, wherein each of the pulse waveforms has one of the data symbols modulated thereon.
Transmit pre-coding
A method for receiving an Orthogonal Frequency Division Multiplexing (OFDM) signal transmitted by a user device in a wireless network comprises determining which subcarrier frequencies are allocated to the user device; converting the OFDM signal to a frequency-domain values corresponding to the subcarrier frequencies; and decoding the frequency-domain values to recover data symbols encoded by the user device on the subcarrier frequencies. The decoding employs codes that are inverse to, complex-conjugate of, or complementary to a set of complex-valued codes employed by the user device to shape the OFDM signal into a superposition of cyclic-shifted pulse waveforms, wherein each of the pulse waveforms has one of the data symbols modulated thereon.
Carrier frequency offset processing method and apparatus and receiver
The invention provides a carrier frequency offset processing method, an apparatus and a receiver. The method comprises: receiving, through a software and hardware interface, an estimated value of frequency offset of a data packet transmitted by an automatic frequency offset control module; collecting the received estimated value of frequency offset of the data packet and performing statistical analysis to obtain a statistical value of carrier frequency offset between a receiving module and a transmitting module; and dynamically adjusting, according to the statistical value of carrier frequency offset, a bandwidth of a low-pass filter through the software and hardware interface. The invention realizes dynamic adjustment of the bandwidth of the low-pass filter in the process of a receiver receiving signals, solving the problem of the impact on processing performance brought by the fixed bandwidth of a low-pass filter in the prior art.
Carrier frequency offset processing method and apparatus and receiver
The invention provides a carrier frequency offset processing method, an apparatus and a receiver. The method comprises: receiving, through a software and hardware interface, an estimated value of frequency offset of a data packet transmitted by an automatic frequency offset control module; collecting the received estimated value of frequency offset of the data packet and performing statistical analysis to obtain a statistical value of carrier frequency offset between a receiving module and a transmitting module; and dynamically adjusting, according to the statistical value of carrier frequency offset, a bandwidth of a low-pass filter through the software and hardware interface. The invention realizes dynamic adjustment of the bandwidth of the low-pass filter in the process of a receiver receiving signals, solving the problem of the impact on processing performance brought by the fixed bandwidth of a low-pass filter in the prior art.
Symbol boundary detection method and processor
A symbol boundary detection method includes: calculating desired signal power according to a receiving signal by a receiver device; calculating interference power according to the receiving signal by the receiver device; calculating a signal-to-interference power ratio according to the desired signal power and the interference power by the receiver device; finding a best signal-to-interference power ratio to determine a reference symbol boundary time by the receiver device; and processing the receiving signal according to the reference symbol boundary time by the receiver device for a subsequent demodulation process performed by a demodulator circuit.
Symbol boundary detection method and processor
A symbol boundary detection method includes: calculating desired signal power according to a receiving signal by a receiver device; calculating interference power according to the receiving signal by the receiver device; calculating a signal-to-interference power ratio according to the desired signal power and the interference power by the receiver device; finding a best signal-to-interference power ratio to determine a reference symbol boundary time by the receiver device; and processing the receiving signal according to the reference symbol boundary time by the receiver device for a subsequent demodulation process performed by a demodulator circuit.
Signal processing device, method of processing signal, and recording medium
A signal processing device includes: an extraction section configured to extract a signal having a predetermined component from an obtained signal; and a detection section configured to determine a timing of decoding when a modulation part lasting for a first time period and a non-modulation part lasting for a second time period are detected from the signal extracted by the extraction section.