Patent classifications
H04L27/3872
Phase-Noise Mitigation by Embedded Phase-Tracking Signals in 5G/6G
Access to FR2 (high frequency bands) is essential for anticipated high-demand networking in 5G-Advanced and 6G systems. Unfortunately, phase noise is an unavoidable barrier, greatly limiting message reliability. Therefore, a low-cost solution is provided in which the transmitter (either base station or user device) transmits a special phase-tracking reference signal consisting of zero amplitude in one branch, and a predetermined non-zero amplitude in the other branch. For example, in QAM, the I-branch may be powered according to the maximum branch amplitude of the modulation scheme, and the Q-branch may have zero amplitude as transmitted. The receiver, on the other hand, generally measures a non-zero amplitude in the received Q branch due to phase noise, which rotates the I and Q branches into each other. The receiver can then determine the phase rotation angle precisely by measuring the non-zero amplitude in the Q branch, negating phase noise at negligible cost.
TRANSMISSION DEVICE, RECEPTION DEVICE, AND TRANSMISSION METHOD
According to one embodiment, a transmission device includes an insertion unit, an allocation unit, a division unit, an IFFT unit, a phase rotation unit, and a transmission unit. The phase rotation unit performs a phase rotation to reduce a PAPR characteristic for each block on which inverse fast Fourier transform has been performed. The transmission unit combines transmission signals, on each of which a phase rotation has been performed by the phase rotation unit, and transmits the combined transmission signal to an external device. In addition, the division unit includes a predetermined band and at least one pilot symbol located outside another of end of this predetermined band on an opposite side of the one end into one block.
PHASE AMBIGUITY PROCESSING METHOD AND DEVICE FOR QUADRATURE AMPLITUDE MODULATION SIGNAL
A phase ambiguity processing method and device are provided. The phase ambiguity processing method includes: deciding symbols on a Y polarization state and an X polarization state of a received signal, and mapping to obtain first bit information, where the received signal includes a plurality of first signals; checking and analyzing the first bit information to generate a first check result; judging the first check result to obtain a judgment result as to whether the received signal has phase ambiguity; acquiring at least one of the plurality of first signals in the received signal when the judgment result indicates that the received signal has phase ambiguity; performing phase rotation on the first signal to obtain a second signal; and checking and analyzing the second signal, storing the second signal so that the first signal is replaced with the second signal for decoding processing if a check result is normal.
Multi-channel spread spectrum return channel for ultra small aperture terminals (USATS)
A return channel system for ultra-small aperture terminals has a spreader that receives an input signal and outputs a spread spectrum signal having multiple replicated signals with a lower power than the input signal. A de-spreader includes a de-multiplexer that receives the spread spectrum signal via satellite. The de-multiplexer separates the spread spectrum signal into a first channel having a first signal and a second channel having a second signal. The de-spreader also has an offset compensation circuit having a phase estimator configured to estimate a phase offset between a phase of the first signal and a phase of the second signal. And a phase adjustor that receives the second signal and adjusts the phase of the second signal to align with the phase of the first signal to provide a phase-adjusted second signal. A summer combines the first signal with the phase-adjusted second signal to provide a composite signal.
Module for a radio receiver
The disclosure relates to a module for a radio receiver. The module comprises an input terminal; an output terminal; a main signal path for communicating in-phase and quadrature signals between the input terminal and the output terminal; and a second signal path. The second signal path is connected in parallel with the main signal path and is configured to: extract in-phase and quadrature signals from the main signal path; filter the extracted in-phase and quadrature signals; detect an error in the filtered, extracted in-phase and quadrature signals; and apply a correction to in-phase and quadrature signals on the main signal path based on the error.
Method and apparatus for peak to average power ratio reduction
One of the embodiments of the present disclosure relates to a method for PARP reduction. The method comprises iteratively adjusting, based on a computed peak power value for a combined transmission signal including respective components of a plurality of frequency resource units, a phase rotation vector which is applied to said respective components of said plurality of frequency resource units to perform phase rotation on said respective components of said plurality of frequency resource units, until a newly-computed peak power value dependent upon the adjusted phase rotation vector is lower than or equal to a pre-defined peak power threshold or an iteration number reaches a pre-defined maximum value; performing phase rotation on said respective components of said plurality of frequency resource units by applying the adjusted phase rotation vector; and transmitting the combined transmission signal of said respective components of said plurality of frequency resource units phase-rotated by said adjusted phase rotation vector. The present disclosure also relates to corresponding transmitter.
Communication apparatus, demodulation apparatus, carrier reproduction apparatus, phase error compensation apparatus, phase error compensation method, and storage medium on which phase error compensation program has been stored
To enable a large-capacity, high-quality data communication that is excellent in bit error rate characteristic even in an adverse noise environment mainly caused by phase noises or thermal noises. [Solution] Included are: a first phase error detection filter that generates, on the basis of a forward sequence of received symbols, a first phase difference value and a first phase error estimated value; a second phase error detection filter that generates, on the basis of a backward sequence of received symbols, a second phase difference value and a second phase error estimated value; a phase error combination means that generates a third phase error estimated value on the basis of the first and second phase error estimated values and one of the first and second phase difference values; and a phase error compensation means that compensates the phase error of the received symbols in accordance with the third phase error estimated value.
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.
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.
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.