Patent classifications
H04L25/0212
Device and method for improving the reception quality of messages in a CAN bus system
A user station for a bus system and a method for improving a reception quality of messages in a user station of a bus system are provided. The user station includes an estimation device for estimating a channel impulse response when and/or after only one further user station of the bus system transmits a message to the bus system, or for determining necessary functions of filters directly from a signal received by the user station, and a correction device for correcting a signal received by the user station based on the channel impulse response estimated by the estimation device.
COMMUNICATION SYSTEM AND COMMUNICATION METHOD
Wireless communication wherein channel estimation accuracy is improved while keeping the position of each bit in a frame, even when a modulation system having a large modulation multiple value is used for a data symbol. An encoding operation encodes and outputs transmitting data (bit string) and a bit converting operation converts at least one bit of a plurality of bits constituting a data symbol to be used for channel estimation, among the encoded bit strings, into 1 or 0. A modulating operation modulates the bit string inputted from the bit converting operation by using a single modulation mapper and a plurality of data symbols are generated.
Matrix equalizer for CMFB transmission in dispersive channels
The present invention is concerned with Cosine Modulated Filter Band modulation, in particular for a matrix equalizer for equalising a modulated signal carrying digital data, wherein the signal is modulated using a CMF6 and transmitted through a transmission channel having a channel impulse response c(t), wherein the matrix equalizer comprises: matrix coefficients W(i) determined based on the discrete-time matrix channel impulse response C(i) that is determined from the channel impulse response c(t); wherein the matrix equalizer is configured to equalize the modulated signal in order to reduce signal distortion introduced by the transmission channel. The present invention also concerns a method for equalising the CMFB modulated signal.
Self-interference channel estimation system and method
The present application describes a self-interference channel estimation system. The system includes a signal generator configured to generate a swept tone having a frequency ranging from an upper edge of a reception band to a lower edge of the reception band, and configured to generate a message signal. The system includes an infinite impulse response (IIR) filter configured to determine an infinite impulse response of a self-interference channel based upon the swept tone. The system includes a processor configured to characterize the self-interference channel based upon the infinite impulse response.
DECISION FEEDBACK EQUALIZATION PROCESSING DEVICE AND METHOD
The present application disclosed a decision feedback equalization processing device and method. The device comprises: a channel estimator for receiving an input signal, and determining, based on the input signal, an input signal autocorrelation matrix R.sub.yy, an input-output signal cross-correlation matrix R.sub.yx and an input-output signal cross-correlation vector r.sub.yx; a tap coefficient calculator for receiving R.sub.yy, R.sub.yx and r.sub.yx, and calculating a feed-forward equalizer (FFE) tap coefficient vector g and a feedback equalizer (FBE) tap coefficient vector f, wherein at least one of the FFE tap coefficient vector g and the FBE tap coefficient vector f is calculated using a conjugate gradient descent algorithm. The tap coefficient calculator comprises: a circulant matrix construction unit and a fast Fourier transformation (FFT) calculating unit. And the device further comprises a decision feedback equalizer for receiving from the tap coefficient calculator the FFE tap coefficient vector g and the FBE tap coefficient vector f, and performing equalization on the input signal and generating an equalized output signal.
OTFS METHODS OF DATA CHANNEL CHARACTERIZATION AND USES THEREOF
Fiber, cable, and wireless data channels are typically impaired by reflectors and other imperfections, producing a channel state with echoes and frequency shifts in data waveforms. Here, methods of using OTFS pilot symbol waveform bursts to automatically produce a detailed 2D model of the channel state are presented. This 2D channel state can then be used to, optimize data transmission. For wireless data channels, an even more detailed 2D model of channel state can be produced by using polarization and multiple antennas in the process. Once 2D channel states are known, the system turns imperfect data channels from a liability to an advantage by using channel imperfections to boost data transmission rates. The methods can be used to improve legacy data transmission modes in multiple types of media, and are particularly useful for producing new types of robust and high capacity wireless communications using non-legacy OTFS data transmission methods.
COMMUNICATION DEVICE, INFRASTRUCTURE EQUIPMENT AND METHODS
A communications device comprising receiver circuitry, transmitter circuitry and controller circuitry controlling the transmitter circuitry and the receiver circuitry to receive data in accordance with an automatic repeat request (ARQ) type protocol in which the data is received as a plurality of encoded data packets encoded with an error correction code and the transmitter circuitry transmits a feedback signal depending on whether each of the data encoded packets is estimated as having been decoded successfully by the receiver circuitry. The controller circuitry is configured to evaluate a quality measure of each encoded data packet and in response to the evaluated quality measure to transmit an early indication of the feedback signal to the wireless communications network, before the encoded data packet has been decoded by the error correction decoder.
COMMUNICATION DEVICE, INFRASTRUCTURE EQUIPMENT AND METHODS
A communications device configured to receive data transmitted as encoded data packets from an infrastructure equipment of a wireless communications network. Each of the encoded data packets are transmitted as a control signal component and a data signal component. The control signal component carries control information for detecting and decoding the data signal component in which the encoded data carried by the encoded data packet is transmitted. As part of the ARQ-type protocol, at least the control signal component may be re-transmitted. By including with the control information carried by the retransmitted control signals an indication of at least a temporal location of the data signal component, which has already been transmitted and received in a buffer of a receiver, an improvement in a use of communications resource can be provided and also in some embodiments an improvement in a likelihood of correctly detecting and decoding an encoded data packet.
System and method for angular-domain channel estimation of massive MIMO system with low-resolution ADC with time-varying thresholds
A receiver for use in a wireless communication system to receive signals transmitted over a wireless channel. The receiver includes a plurality of radio-frequency (RF) chains coupled a plurality of antennas. Each RF chain has at least one-bit analog-to-digital converter (ADC) to convert each measurement of an analog signal received by the antenna into at least one bit of information representing a result of a comparison of the measurement with a randomly selected threshold to produce a sequence of bits and a corresponding sequence of thresholds. Each bit in the sequence of bits represents a relative value of the measurement of the analog signal with respect to a threshold from the corresponding sequence of thresholds. A processor coupled to the plurality of RF chains estimates parameters of the wireless channel using the sequences of bits and the corresponding sequences of thresholds received from the plurality of RF chains.
SUB-BAND BASED COMPOSITE DIGITAL TIME DOMAIN SIGNAL PROCESSING
Embodiments include digital signal processing units, a transmitting device for a wireless communication system and methods of processing a composite time domain signal having a plurality of parallel and independent signals that collectively form a parallel communication. It is proposed a new waveform configuration suitable for 5G and that is able to reduce out-of-band (OOB) emissions which are received on a first time domain signal associated to a first sub-band where the OOB emissions originate from an OFDM time domain signal associated with a second sub-band adjacent to the first sub-band. The proposed solution is partly based on filtered-OFDM with the exception that sub-band filtering is not performed on all the samples of the stream of OFDM symbols. Instead, filtering is performed only, for each OFDM time domain signal, where transition occurs between consecutive OFDM symbols.