Patent classifications
H04L27/3494
SPACE TIME BLOCK CODES FOR SEMI-ORTHOGONAL MULTI-ACCESS BASED WLAN SYSTEMS
The disclosed systems, structures, and methods are directed to a wireless local area network (WLAN) transmission architecture and transmitting methodology that combines space-time block code (STBC) encoding techniques with semi-orthogonal multiple access (SOMA) schemes to improve throughput rate performance for lower signal strength data. The transmission architecture and method includes a data processing module that is configured to digitally process and format data produced by two wireless stations. A SOMA constellation quadrature encoding module operates to apply quadrature-based modulation to the processed data and map the data to a modulation constellation based on data signal strength and data bit reliability. An STBC encoding module is configured to block encode the SOMA modulated data with orthogonal codes to produce STBC-based SOMA-symbol data having time and space diversity properties that improve throughput performance at lower signal strength levels.
High spectral efficiency data communications system using energy-balanced modulation
A data communications system and method having high spectral efficiency. The method includes encoding input digital data using a plurality of symbol waveforms. Each symbol waveform occupies a period of a composite encoded waveform and represents one or more bits of the input digital data. Each symbol waveform has a first elliptical segment and a second elliptical segment of opposite polarity. The encoding includes defining each symbol waveform so that (i) a zero crossing from the first elliptical segment to the second elliptical segment of the symbol waveform is different for each of the symbol waveforms, and (ii) an energy of the first elliptical segment of the symbol waveform is substantially equal to an energy of the second elliptical segment of the symbol waveform. An encoded analog waveform is generated, using a digital-to-analog converter, from a digital representation of the composite encoded waveform.
High spectral efficiency data communications system using encoded sinusoidal waveforms
A system and method for waveform modulation includes encoding input digital data at selected phase angles of an unmodulated sinusoidal waveform. The encoding includes selectively reducing a power of the unmodulated sinusoidal waveform at the selected phase angles in accordance with bit values of the input digital data so as to respectively define first, second, third and fourth data notches in the modulated sinusoidal waveform. An encoded analog waveform is then generated from a digital representation of the modulated sinusoidal waveform. The encoding is performed so that energies associated with the first and third data notches are balanced and energies associated with second and fourth data notches are also balanced. Each of the energies corresponds to a cumulative power difference between a power of the unmodulated sinusoidal waveform and a power of the modulated sinusoidal waveform over a phase angle range subtended by one of the data notches.
Communication system using shape-shifted sinusoidal waveforms
A data communication method in which input digital data is received and encoded into an encoded waveform having zero crossings representative of the input digital data. The encoding includes generating the encoded waveform based upon a continuous piecewise function having sinusoidal components. The continuous piecewise function may be used in generating a plurality of symbol waveforms, each of which occupies a period of the encoded waveform and represents bits of the input digital data. The plurality of symbol waveforms are defined so that a value of a phase offset used in the continuous piecewise function is different for each of the plurality of symbol waveforms, thereby resulting in each symbol waveform having a different zero crossing. An encoded analog waveform is generated from a representation of the encoded waveform and transmitted to a receiver.
Systems, devices and methods for communicating data over circularly pulse-shaped waveforms
Circularly pulse-shaped waveforms for communication systems are disclosed herein, including a single carrier modulation in which pulse-shaping is performed using a circular convolution by the transmitter for various modulation schemes. A transmitter, related method, and corresponding receiver are also disclosed for demodulation of the single carrier circularly pulse-shaped signal and data extraction.
System for encoding multi-bit features into sinusoidal waveforms at selected phase angles
A system and method for encoding multi-bit features into sinusoidal waveforms at selected phase angles. The method includes receiving input digital data and encoding the input digital data in a sinusoidal waveform by modulating the sinusoidal waveform at selected phase angles within a period of the sinusoidal waveform, thereby creating a modulated sinusoidal waveform. An encoded analog waveform is generated, using a digital-to-analog converter, from a digital representation of the modulated sinusoidal waveform. The modulating includes forming a first data notch at a first phase angle of the selected phase angles wherein the first data notch includes a first plurality of transition features and subtends a first phase angle range about the first phase angle, the first plurality of transition features being representative of a first plurality of bit values included within the input digital data.
TECHNIQUES FOR WAVEFORM COMPRESSION
Methods, systems, and devices for wireless communications are described. A user equipment (UE) may generate an input signal including information for transmission over a wireless channel. The UE may perform a first waveform shaping stage on the input signal to increase an in-band emissions ratio and reduce a peak-to-average power ratio (PAPR) of the input signal. The UE may perform a second waveform shaping stage on the output of the first waveform shaping stage to reduce an adjacent channel leakage ratio of the output of the first waveform shaping stage. The UE may then transmit a signal over the wireless channel based on an output of the second waveform shaping stage.
Multi-carrier data communications system having high spectral efficiency
A multi-carrier data communications system and method having high spectral efficiency. The method includes encoding input digital data at selected phase angles of a plurality of sinusoidal waveforms to create a plurality of modulated sinusoidal waveforms. An output analog waveform is generated where the output analog waveform includes a plurality of encoded analog communication signals corresponding to a plurality of digital representations of the plurality of modulated sinusoidal waveforms. The encoding is performed so that adjacent ones of the plurality of modulated sinusoidal waveforms are separated in frequency by less than 15 Hz and any sideband included within the output analog waveform is of a power at least 50 dB below a power of the encoded analog communication signal associated with the sideband.
DATA PROCESSING APPARATUS, DATA PROCESSING METHOD, AND PROGRAM
A data processing apparatus, a data processing method, and a program are disclosed. They improve communication performance by performing bit interleaving suitable for a modulation method that is a non-uniform constellation. One example of a data processing apparatus includes a mapping unit configured to generate a second bit sequence by mapping a first bit sequence to any symbol on a complex plane corresponding to a NUC modulation method, an inter-symbol interleaving unit configured to generate a third bit sequence by performing inter-symbol interleaving to the second bit sequence, an intra-symbol interleaving unit configured to generate a fourth bit sequence by performing intra-symbol interleaving for shifting M bits as a whole of the third bit sequence per a same number of M bits as the bit number M representing the symbol, and a modulation unit configured to wirelessly transmit the fourth bit sequence according to the NUC modulation method.
Receiver for high spectral efficiency data communications system using encoded sinusoidal waveforms
A method of recovering information encoded by a modulated sinusoidal waveform having first, second, third and fourth data notches at respective phase angles, where a power of the modulated sinusoidal waveform is reduced relative to a power of an unmodulated sinusoidal waveform within selected ones of the first, second, third and fourth data notches so as to encode input digital data. The method includes receiving the modulated sinusoidal waveform and generating digital values representing the modulated sinusoidal waveform. A digital representation of the unmodulated sinusoidal waveform is subtracted from the digital values in order to generate a received digital data sequence, which includes digital data notch values representative of the amplitude of the modulated sinusoidal waveform within the first, second, third and fourth data notches. The input digital data is then estimated based upon the digital data notch values.