Back to results
US 11,902,078 B2Granted
Methods and apparatuses for signaling with geometric constellations
AssigneeConstellation Designs, LLC
InventorsMaged F. Barsoum, Christopher R. Jones
Life of this patent
Estimating the term…
Abstract
Communication systems are described that use signal constellations, which have unequally spaced (i.e. ‘geometrically’ shaped) points. In many embodiments, the communication systems use specific geometric constellations that are capacity optimized at a specific SNR. In addition, ranges within which the constellation points of a capacity optimized constellation can be perturbed and are still likely to achieve a given percentage of the optimal capacity increase compared to a constellation that maximizes dmin, are also described. Capacity measures that are used in the selection of the location of constellation points include, but are not limited to, parallel decode (PD) capacity and joint capacity.
Claims47
A digital communication system, comprising:
- a transmitter configured to transmit signals via a communication channel;
- wherein the transmitter comprises:
- a coder capable of receiving bits and outputting encoded bits using a Low Density Parity Check (LDPC) code;
- a mapper, coupled to the coder, capable of mapping the encoded bits to symbols in a non-uniform quadrature amplitude modulation 1024-point symbol constellation (NU-QAM 1024);
- and
- a modulator, coupled to the mapper, capable of producing a signal for transmission via the communication channel based upon symbols selected by the mapper;
- wherein the NU-QAM 1024 constellation comprises an in-phase component and a quadrature component, where each component comprises 32 levels of amplitude such that the amplitudes scaled by a scaling factor are within 0.15 from the following set of amplitudes:
- −34.448, −30.817, −27.660, −24.807, −22.185, −19.751, −17.476, −15.333, −13.305, −11.366, −9.509, −7.701, −5.953, −4.220, −2.533, −0.834, 0.833, 2.533, 4.220, 5.953, 7.701, 9.509, 11.366, 13.305, 15.333, 17.476, 19.752, 22.186, 24.808, 27.660, 30.818, and 34.449.
5 more elements
A communication system, comprising:
- a receiver capable of receiving signals via a communication channel having a channel signal-to-noise ratio (SNR), wherein the receiver comprises:
- a demodulator capable of demodulating a received signal into a demodulated signal;
- a demapper, coupled to the demodulator, capable of determining likelihoods using the demodulated signal and a non-uniform quadrature amplitude modulation 1024-point symbol constellation (NU-QAM 1024);
- and
- a decoder, coupled to the demapper, capable of using likelihoods determined by the demapper to provide a sequence of received bits based upon a Low Density Parity Check (LDPC) code;
- wherein the NU-QAM 1024 constellation comprises an in-phase component and a quadrature component, where each component comprises 32 levels of amplitude such that the amplitudes scaled by a scaling factor are within 0.15 from the following set of amplitudes:
- −34.448, −30.817, −27.660, −24.807, −22.185, −19.751, −17.476, −15.333, −13.305, −11.366, −9.509, −7.701, −5.953, −4.220, −2.533, −0.834, 0.833, 2.533, 4.220, 5.953, 7.701, 9.509, 11.366, 13.305, 15.333, 17.476, 19.752, 22.186, 24.808, 27.660, 30.818, and 34.449.
4 more elements
A digital communication system, comprising:
- a transmitter configured to transmit signals to a receiver via a communication channel;
- wherein the transmitter comprises:
- a coder capable of receiving bits and outputting encoded bits using a Low Density Parity Check (LDPC) code;
- a mapper, coupled to the coder, capable of mapping the encoded bits to symbols in a non-uniform quadrature amplitude modulation 1024-point symbol constellation (NU-QAM 1024);
- and
- a modulator, coupled to the mapper, capable of producing a signal for transmission via the communication channel based upon symbols selected by the mapper;
- and
- a receiver capable of receiving signals via the communication channel at a channel signal-to-noise ratio (SNR), wherein the receiver comprises:
- a demodulator capable of demodulating a received signal into a demodulated signal;
- a demapper, coupled to the demodulator, capable of determining likelihoods using the NU-QAM 1024;
- and
- a decoder, coupled to the demapper, capable of using likelihoods determined by the demapper to provide a sequence of received bits based upon the LDPC code;
- wherein the NU-QAM 1024 constellation comprises an in-phase component and a quadrature component, where each component comprises 32 different of amplitude such that the amplitudes scaled by a scaling factor are within 0.55 from the following set of amplitudes:
- −34.448, −30.817, −27.660, −24.807, −22.185, −19.751, −17.476, −15.333, −13.305, −11.366, −9.509, −7.701, −5.953, −4.220, −2.533, −0.834, 0.833, 2.533, 4.220, 5.953, 7.701, 9.509, 11.366, 13.305, 15.333, 17.476, 19.752, 22.186, 24.808, 27.660, 30.818, and 34.449.
11 more elements
Dependencies are inferred from the claim text.