Patent classifications
H04L27/3872
JOINT NONCOHERENT DEMODULATION AND CARRIER FREQUENCY OFFSET CORRECTION BASED ON NON-LINEAR FILTERING
A wireless device, and corresponding method, having a receiver configured to receive a signal having in-phase and quadrature components; a non-linear filter demodulator configured to translate noncoherently the in-phase and quadrature components into phase and frequency domain signals, and to estimate and correct carrier frequency offset; a coherence signal parameter acquisition unit is configured to estimate and correct at least one correct coherence signal parameter based on the in-phase and quadrature components and the phase or frequency domain signal; and a symbol detector is configured to detect information in the phase or frequency domain signal. If optimal coherent information detection is desired, the at least one signal parameter is not only carrier phase offset and carrier timing offset, but also phase frequency offset, wherein the estimation and correction of the carrier frequency offset performed by the signal parameter acquisition unit is more precise than that performed by the non-linear filter demodulator. In such a case the detector is configured to detect information in the phase domain signal.
Method and apparatus for estimating and correcting phase error in wireless communication system
Provided are a method and apparatus for estimating and correcting the phase error in 5G or pre-5G communication systems providing much higher data rates compared to existing 4G communication systems including LTE systems. The existing phase error estimation scheme using a cyclic prefix in the time domain may fail to prevent performance degradation due to inter-carrier interference. In the present invention, it is possible to enhance reception performance of the receiver by estimating and correcting the phase error multiple times within a symbol using a time domain signal and by reducing the influence of inter-carrier interference.
Ultra-Compact Phase-Tracking Demodulation Reference for 5G/6G
In 5G-Advanced and 6G, due to the higher frequencies involved, phase noise is expected to be a major source of faults. Disclosed herein is a small (single resource element) phase-tracking reference signal that also provides an updated amplitude calibration. The compact phase-tracking reference signal, in QAM, includes a first branch at a maximum amplitude and an orthogonal second branch at either the maximum amplitude or zero amplitude, as transmitted. The receiver can readily determine a phase rotation angle according to a ratio of the two branch amplitudes, and also an amplitude calibration according to the vector magnitude of the received branches, thereby negating both amplitude noise and phase noise.
Techniques for partial transmit sequence transmission using multi-mode index modulation
Methods, systems, and devices for wireless communications are described. A transmitting wireless device may identify different sets of bits that are included in information bits of a signal to be transmitted. For example, a first set of bits may be used as an index for a second set of bits, and the second set of bits may include multiple groups of bits, where each group may have a same size (e.g., a same quantity of bits). Based on the groups of bits having the same size, the transmitting wireless device may obtain candidate partial transmit sequences (PTSs) based on applying phase rotations to respective inverse Fast Fourier Transform (IFFT) outputs associated with each group of bits. The transmitting wireless device may select a PTS from the candidate PTSs and may transmit the signal including the information bits to a receiving wireless device using the selected PTS.
Apparatus, system and method of communicating a transmission according to a rotated 256 quadrature amplitude modulation (QAM) scheme
Some demonstrative embodiments include apparatus, system and method of communicating a transmission according to a rotated 256 Quadrature Amplitude Modulation (QAM) scheme. For example, an apparatus may include logic and circuitry configured to cause a wireless station to modulate a Single Carrier (SC) transmission according to a rotated 256-QAM scheme; and to transmit the SC transmission over a millimeter Wave (mmWave) frequency band.
Homodyne receiver calibration
There is disclosed mechanisms for calibrating a homodyne receiver in a signal distribution network for time division duplex; a corresponding method is performed by a baseband calibration module. The method comprises acquiring a transmission signal being input to a homodyne transmitter of the signal distribution network; acquiring, from a heterodyne transmitter observation receiver of the signal distribution network, a first received version of the transmission signal; acquiring, from a homodyne receiver of the signal distribution network, a second received version of the transmission signal; and, calibrating the homodyne receiver using a comparison of the first received version of the transmission signal and the second received version of the transmission signal, using the first received version of the transmission signal as a reference signal, and using the transmission signal as a calibration signal.
Apparatus and Method for Reducing Effects of Phase Noise
The proposed solution relates to a method and an apparatus in a communication system. The solution includes receiving as an input a frame including of a set of data symbols and reference symbols, each data symbol forming a rectangular symbol constellation of samples, derotating the first symbol of the set on the basis of the reference symbols, and setting phase rotating angle of the first symbol as zero. The solution further includes for each following successive symbol in the set of symbols: performing equalization; reducing the number of samples in the constellation by selecting samples in two or more corners of the constellation by utilising two or more threshold values; estimating the phase rotating angle of the symbol from the reduced number of samples and derotating the symbol on the basis of the determined phase rotating angle.
System and method for enhancing channel estimation at a receiver
Disclosed is a receiver for enhancing estimation of a channel of a received signal. The receiver is being configured to (i) process at least one of (a) power control commands to obtain a pattern of processed power control commands or (b) phase estimation to obtain a pattern of processed phase estimation; (ii) match the pattern of at least one of (a) processed power control commands, or (b) processed phase estimation to a pattern corresponding to one or more channels; (iii) determine a type of channel of the one or more channels based on the matched pattern of at least one of (a) said processed power control commands, or (b) said processed phase estimation, (iv) determine filtering parameters based on a type of channel that is determined and (v) enhance estimation of the channel based on the filtering parameters associated with the type of channel that is determined.
OFDM-Based Data Transmission Method And Apparatus
Embodiments of the present disclosure relate to an OFDM-based data transmission method and an apparatus. In one example method, a transmitting device generates a data packet. The data packet comprises at least one orthogonal frequency division multiplexing (OFDM) symbol. The OFDM symbol comprises N sequentially numbered subcarriers. The N subcarriers are divided into L subblocks. Each subblock of the L subblocks comprises N/L subcarriers including M pilot subcarriers. Start subcarriers of adjacent subblocks are adjacently numbered subcarriers. A numbering interval is the same for adjacent subcarriers in each subblock of the L subblocks. Each subblock of the L subblocks corresponds to one phase rotation signal. Signals carried on the subcarriers in each subblock of the L subblocks are signals obtained by multiplying original signals by a corresponding phase rotation signal. The transmitting device sends the data packet.
HOMODYNE RECEIVER CALIBRATION
There is disclosed mechanisms for calibrating a homodyne receiver in a signal distribution network for time division duplex; a corresponding method is performed by a baseband calibration module. The method comprises acquiring a transmission signal being input to a homodyne transmitter of the signal distribution network; acquiring, from a heterodyne transmitter observation receiver of the signal distribution network, a first received version of the transmission signal; acquiring, from a homodyne receiver of the signal distribution network, a second received version of the transmission signal; and, calibrating the homodyne receiver using a comparison of the first received version of the transmission signal and the second received version of the transmission signal, using the first received version of the transmission signal as a reference signal, and using the transmission signal as a calibration signal.