Broadcom Corporation

Alvin Lai Lin

Andrew John Blanksby

Accumulating LDPC (Low Density Parity Check) decoder. The accumulating decoding architecture described herein is applicable to LDPC codes operating on a parity check matrix, H, consisting of CSI (Cyclic Shifted Identity) sub-matrices (or matrix sub-blocks) or permuted identity sub-matrices (or matrix sub-blocks). In such a structure, the entire LDPC matrix is broken into square sub-matrices such that each sub-matrix consists of either a CSI sub-matrix or a permuted identity sub-matrix, or a null matrix. The iterative decoding process operates by updating of APP (a posteriori probability) or gamma (&#x3b3;) values and check edge message (&#x3bb;) values, and this by updating one or more individual rows within a number of sub-matrix rows (or all sub-matrix or sub-block rows) are processed in parallel. The amount of parallelism is specified by the designer and is typically an integer divisor of the sub-matrix (or sub-block) size.

Accumulating LDPC (low density parity check) decoder

The accumulating decoding architecture described herein is applicable to LDPC codes operating on a parity check matrix, H, consisting of CSI (Cyclic Shifted Identity) sub-matrices (or matrix sub-blocks) or permuted identity sub-matrices (or matrix sub-blocks). In such a structure, the entire LDPC matrix is broken into square sub-matrices such that each sub-matrix consists of either a CSI sub-matrix or a permuted identity sub-matrix, or a null matrix. The iterative decoding process operates by updating of APP (a posteriori probability) or gamma (&#x3b3;) values and check edge message (&#x3bb;) values, and this by updating one or more individual rows within a number of sub-matrix rows (or all sub-matrix or sub-block rows) are processed in parallel. The amount of parallelism is specified by the designer and is typically an integer divisor of the sub-matrix (or sub-block) size.

Permuted accelerated LDPC (Low Density Parity Check) decoder. This decoding approach operates by processing, in parallel, selected rows for multiple individual LDPC matrix rows from various sub-matrix rows (e.g., first group of rows from a first sub-matrix row, second group of rows from a second sub-matrix row, etc.). A memory structure of daisy chains is employed for memory management of APP (a posteriori probability) values and also for check edge messages/intrinsic information (&#x3bb;) values. A first group of daisy chains may be employed for memory management of the APP values, and a second group of daisy chains may be employed for memory management of the check edge messages. These daisy chains operate to effectuate the proper alignment of APP (or gamma(&#x3b3;)) values and check edge message/intrinsic information (&#x3bb;) values for their respective updating in successive decoding iterations.

Permuted accelerated LDPC (Low Density Parity Check) decoder

Distributed processing LDPC (Low Density Parity Check) decoder. A means is presented herein that includes an LDPC decoding architecture leveraging a distributed processing technique (e.g., daisy chain) to increase data throughput and reduce memory storage requirements. Routing congestion and critical path latency are also improved thereby. Each daisy chain includes a number of registers, and a number of localized MUXs (e.g., MUXs having merely 2 inputs each). The means presented herein also does not contain any barrel shifters, high fan-in multiplexers, or interconnection networks; therefore, the critical path is relatively short and it can also be pipelined to further increase data throughput. If desired, a communication device can include multiple configurations of such daisy chains to accommodate the decoding of various LDPC coded signals (e.g., such as for an application and/or communication device that must decoded LDPC codes using different low density parity check matrices).

Distributed processing LDPC (low density parity check) decoder

Multi-code LDPC (Low Density Parity Check) decoder. Multiple LDPC coded signals can be decoded using hardware provisioned for a minimum requirement needed to decode each of the multiple LDPC coded signals. In embodiments where each LDPC matrix (e.g., employed to decode each LDPC coded signal) includes a common number of non-null sub-matrices, then a same number of memories are employed when decoding each LDPC coded signal. However, those particular memories employed can be different subsets for when decoding each LDPC coded signal. In embodiments where each LDPC code includes a different number of non-null sub-matrices within its respective LDPC matrix, then a different number of memories are employed when decoding each LDPC coded signal. Various degrees of parallelism in decoding can also be employed in which different numbers of bit engines and check engines can be employed when decoding different LDPC coded signals.

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Londonderry, United Kingdom

Alvin Lai Lin