Patent classifications
H04L25/03834
Modulation and equalization in an orthonormal time-frequency shifting communications system
A method for modulating data for transmission within a communication system. The method includes establishing a time-frequency shifting matrix of dimension N×N, wherein N is greater than one. The method further includes combining the time-frequency shifting matrix with a data frame to provide an intermediate data frame. A transformed data matrix is provided by permuting elements of the intermediate data frame. A modulated signal is generated in accordance with elements of the transformed data matrix.
Systems and methods for ultra wideband impulse radio transceivers
Ultra-Wideband (UWB) technology exploits modulated coded impulses over a wide frequency spectrum with very low power over a short distance for digital data transmission. Today's leading edge modulated sinusoidal wave wireless communication standards and systems achieve power efficiencies of 50 nJ/bit employing narrowband signaling schemes and traditional RF transceiver architectures. However, such designs severely limit the achievable energy efficiency, especially at lower data rates such as below 1 Mbps. Further, it is important that peak power consumption is supportable by common battery or energy harvesting technologies and long term power consumption neither leads to limited battery lifetimes or an inability for alternate energy sources to sustain them. Accordingly, it would be beneficial for next generation applications to exploit inventive transceiver structures and communication schemes in order to achieve the sub nJ per bit energy efficiencies required by next generation applications.
Systems and method for distortion compensation
A method and apparatus of distortion compensation during data transmission uses an interweaved look-up table (ILUT) to mitigate residual signal distortions in a signal transmitted over a transmission link. The ILUT interweaves states across both an I and a Q tributary to calculate mean error and an extended symbol basis. As a result, the method works particularly well against two-dimensional distortions like nonlinearity, IQ-imbalance, and quadrature error. The method may be used for either pre-compensation when it is combined with k-means clustering in a transmitter or post-compensation when it is combined with maximum likelihood (ML) detection in a receiver.
Apparatus and method for adjusting both a cyclic prefix length and a symbol interval of a complex symbol sequence
[Object] To adaptively adjust a symbol interval in accordance with a communication environment. [Solution] An apparatus including: a communication unit configured to perform radio communication; and a control unit configured to perform control such that control information for adjusting a symbol interval in a complex symbol sequence into which a bit sequence is converted is transmitted from the communication unit to a terminal, the control information being set on a basis of a predetermined condition.
Asynchronous polar transmitter and operation method thereof
A polar transmitter is provided. The polar transmitter includes a baseband generation unit configured to generate phase data bits and amplitude data bits of an output pulse. The polar transmitter further includes a bandwidth control unit downstream to the baseband generation unit configured to regulate the width of the output pulse. Moreover, the polar transmitter includes a pulse shaping unit downstream to the bandwidth control unit configured to generate a predefined amplitude envelope of the output pulse. In this context, the pulse shaping unit includes a delay-line with a plurality of taps, where each tap output is configured to be amplitude weighted in order to generate the amplitude envelope of the output pulse.
ANALOG FRACTIONAL-N PHASE-LOCKED LOOP
An analog fractional-N phase-locked loop includes an oscillator loop having a reference input, a feedback input, and a loop output, and a fractional feedback divider configured to divide signals on the loop output by a divisor. Output of the fractional feedback divider is fed back to the feedback input. A compensation circuit is coupled to, and configured to apply a time delay to, the reference input or the feedback input, to compensate for delay introduced by the fractional feedback divider. The compensation circuit may be a digital-to-time converter configured to convert a digital delay signal into the time delay. The digital-to-time converter may be coupled to the reference input to delay signals to match feedback delay introduced by the fractional feedback divider, or to the feedback input to subtract the time delay to cancel feedback delay introduced by the fractional feedback divider.
Spectral Shaping with Spectrum Extension for Reference Signals for Wireless Networks
A method may include receiving, by a user device from a network node, information indicating a set of frequency resources assigned to the user device for uplink transmission and a spectrum shaping configuration indicating at least spectrum shaping with spectrum extension for transmission of reference signals via the set of frequency resources; performing, by the user device, spectrum shaping with spectrum extension for a reference signal; and transmitting the spectrum shaped and extended reference signal via at least a portion of the set of frequency resources.
PILOT TRANSMISSION METHOD AND DEVICE
Embodiments of this application disclose a pilot transmission method and device. The method includes: inserting, by a communications device, a pilot symbol into a first data sequence to obtain a second data sequence; and transmitting, by the communications device, the second data sequence, where the second data sequence has been subjected to faster-than-Nyquist processing.
Pre-coding in a faster-than-Nyquist transmission system
The invention refers to faster than Nyquist communication system wherein a set of symbols is conveyed from a transmitter (21) to a receiver (23), wherein the transmitter (21) and the receiver (23) are coupled by means of a transmission channel (22), comprising a precoder (210) adapted for generating a set of precoded symbols from a set of input symbols by performing a matrix operation with a precoding matrix, a pulse filter (212) adapted for generating a transmission signal to be transmitted over the transmission channel (22) as a function of the precoded symbols, a receiving filter (230) adapted for generating a set of sampled symbols as a function of the transmission signal and noise added by the transmission channel, and a decoder (232) adapted for generating a set of decoded symbols as a function of the set of sampled symbols, wherein the elements of the precoding matrix are dependent on a property of the pulse filter (212), The invention further refers to a transmitter, a receiver and corresponding methods, and to a user equipment and a base station.
Systems and methods for transmitting data via a cable
A method for transmitting data via a coaxial electrical cable includes (a) converting symbols of each input data stream of a plurality of parallel input data streams from digital form to analog form, (b) individually filtering symbols of each input data stream, (c) transforming symbols of each input data stream from a first frequency-domain to a first time-domain, to generate parallel first time-domain samples, (d) converting the first time-domain samples to a serial multi-carrier signal, and (e) injecting the multi-carrier signal onto the coaxial electrical cable.