Patent classifications
H04L27/26265
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.
HETEROGENEOUS WEIGHTED OVERLAP-ADD WINDOWING AND FILTERING FOR ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING WAVEFORMS
Techniques for processing of symbols (e.g., orthogonal frequency division multiplexing (OFDM) or single carrier-frequency division multiple access (SC-FDMA) symbols) provide enhanced out-of-band (OOB) suppression of the symbols and also provide reduced inter-symbol interference (ISI) between a symbol and a subsequent symbol. Multiple frequency tones of a symbol may be divided into two or more subsets of tones. For example, subsets of tones associated with a head portion or a tail portion of an OFDM symbol may be processed with a relatively long weighted overlap-add (WOLA) weighting length or filtering length, and a subset of tones associated with a center portion of the OFDM symbol may be processed with a relatively short WOLA weighting length or filtering length. Such heterogeneous processing of tones within a symbol may provide enhanced inter-channel interference (ICI) and improved OOB suppression and also provide reduced ISI for the center tones of the symbol.
WIRELESS COMMUNICATION APPARATUS AND THE METHOD THEREOF
In one exemplary embodiment, a wireless communication apparatus transmitting data by using several sub-carriers. The wireless communication apparatus comprises a signal modulator, a signal processor, a storage, a computing processor, and a transmitter. The signal modulator generates a modulated signal in time domain based on the data. The signal processor perfoiliis signal processing on the modulated signal, and comprises a window module and a filter module. The window module performs windowing operation on the modulated signal to generate a window-operated signal. The filter module performs filtering operation on the window-operated signal to generate a transmitting signal in time domain. The computing processor perfoiiiis operations of setting up the window module and the filter module according to a window characteristic function and a filter characteristic function. The transmitter transmits the transmitting signal.
Communication device with power amplifier crest factor reduction
Various embodiments include a power amplifier with crest factor reduction embodied by first circuitry for producing a correlated out-of-band noise signal for controlling the adjacent channel leakage ratio (ACLR) of a communication device; and second circuitry for providing an output signal for controlling the error vector magnitude (EVM) of a digital radio. The ACLR and the EVM are concurrently individually controllable. Additional apparatus is described.
METHOD AND DEVICE FOR MITIGATING INTER-CELL INTERFERENCE
The present invention provides a method for mitigating inter-cell interference. To this end, the present invention can comprise a second signal transmission step in which, when a transmission symbol to be transmitted to a first receiver is S and a transmission symbol to be transmitted to a second receiver is Z, a symbol S2k (k is an integer) is transmitted to the first receiver through a first transmission antenna according to a first pattern, a symbol S2k* is transmitted to the first receiver through a second transmission antenna, a symbol S2k+1 is transmitted to the first receiver through a third transmission antenna, a symbol S2k+1* is transmitted to the first receiver through a fourth transmission antenna, and symbols Z4k to Z4k+3 and symbols Z4k* to Z4k+3* are transmitted to the second receiver through fifth to eighth transmission antennas according to a second pattern different from the first pattern.
VEHICLE RADAR SYSTEM USING SHAPED ANTENNA PATTERNS
A radar sensing system for a vehicle, the radar sensing system including a transmitter and a receiver. The transmitter is configured to transmit a radio signal. The receiver is configured to receive the transmitted radio signal reflected from objects in the environment. The transmitter includes an antenna and is configured to transmit the radio signal via the antenna. The antenna includes a plurality of linear arrays of patch radiators. An arrangement of the linear arrays of patch radiators is selected to form a desired shaped antenna pattern having a desired mainlobe shape and desired shoulder shapes to cover selected sensing zones without nulls or holes in the coverage.
Transmission apparatus, reception apparatus, and communication system
A transmission apparatus that transmits a block signal that includes a plurality of data symbols, includes: a symbol generation unit that generates data symbols; a fixed-symbol arrangement unit that generates a block symbol by arranging data symbols and fixed symbols such that the fixed symbols are inserted at predetermined positions in a block signal; a time-frequency conversion unit that converts the block symbol to a frequency domain signal that includes N samples; an interpolation processing unit that performs interpolation processing on the frequency domain signal; and a CP insertion unit that generates the block signal by inserting a Cyclic Prefix into a signal that has undergone the interpolation processing.
Partial channel filtering
Various communication systems may benefit from improved radio signaling. For example, communication systems may benefit from selective or partial filtering of a radio signal. A method, in certain embodiments, may include analyze at a network entity a radio signal comprising a plurality of orthogonal frequency division multiplexing symbols. The radio signal comprises at least one point of discontinuity between the plurality of symbols. The method may also include filtering a select time domain sample of the radio signal in the plurality of symbols. The select sample surrounds the at least one point of discontinuity. In addition, the method may include replacing the select time domain sample surrounding the at least one point of discontinuity of the radio signal with the filtered sample in the plurality of symbols.
Spectrum shaping for OFDM/DMT
There is provided spectrum shaping of a signal. A frequency-domain representation of the signal to be spectrum-shaped is provided. The signal is associated with a set of constellation points having a minimum distance. A spectrum-shaped signal is determined by altering a proper subset of the constellation points while maintaining the minimum distance between all of the constellation points. The spectrum-shaped signal is transformed into a time-domain signal.
Method of filtering digital signal for maintaining data transmission rate in TDD or TDMA system and communication system adopting the same
Provided is a digital filter implementing a function by using circular convolution of a digital input signal and a unit pulse response of the digital filter in applying a filter to the digital signal. In addition, a configuration sequence change of an output signal, which occurs as a result of digital filtering according to the present invention, in comparison to an input signal, is corrected by inversely performing circular shifting in a transmitter by amount of the configuration sequence change, or by reconstructing a signal after making synchronization and acquiring the signal previous to a time point of the synchronization by amount of the configuration sequence change, in a receiver.