Patent ID: 11864007
Assignee: CONSTELLATION DESIGNS, LLC
Field: Digital communication (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 47:
48. A communication system, comprising:
a sink device capable of receiving data bits;
a receiver that receives signals via a communication channel having a channel signal-to-noise ratio (SNR) and provides data bits to the sink device;
wherein the receiver uses a symbol constellation selected from a set of symbol constellations and a low density parity check (LDPC) code selected from a set of LDPC codes having different code rates to transform the received signals into received bits;
wherein the set of symbol constellations comprises:
an unequally spaced Quadrature Amplitude Modulated 64 point (QAM-64) symbol constellation; and
a uniformly spaced QAM-64 signal constellation that maximizes the minimum distance, dmin, between the constellation points;

wherein use of a specific LDPC code having a code rate that is greater than 1/2 from the set of LDPC codes in combination with the unequally spaced QAM-64 symbol constellation provides a larger gain than the gains achieved using the unequally spaced QAM-64 symbol constellation in combination with any of the other LDPC codes from the set of LDPC codes.