493 research outputs found
Threshold-Based Fast Successive-Cancellation Decoding of Polar Codes
Fast SC decoding overcomes the latency caused by the serial nature of the SC
decoding by identifying new nodes in the upper levels of the SC decoding tree
and implementing their fast parallel decoders. In this work, we first present a
novel sequence repetition node corresponding to a particular class of bit
sequences. Most existing special node types are special cases of the proposed
sequence repetition node. Then, a fast parallel decoder is proposed for this
class of node. To further speed up the decoding process of general nodes
outside this class, a threshold-based hard-decision-aided scheme is introduced.
The threshold value that guarantees a given error-correction performance in the
proposed scheme is derived theoretically. Analysis and hardware implementation
results on a polar code of length with code rates , , and
show that our proposed algorithm reduces the required clock cycles by up
to , and leads to a improvement in the maximum operating frequency
compared to state-of-the-art decoders without tangibly altering the
error-correction performance. In addition, using the proposed threshold-based
hard-decision-aided scheme, the decoding latency can be further reduced by
at ~dB.Comment: 14 pages, 8 figures, 5 tables, submitted to IEEE Transactions on
Communication
Partitioned Successive-Cancellation List Decoding of Polar Codes
Successive-cancellation list (SCL) decoding is an algorithm that provides
very good error-correction performance for polar codes. However, its hardware
implementation requires a large amount of memory, mainly to store intermediate
results. In this paper, a partitioned SCL algorithm is proposed to reduce the
large memory requirements of the conventional SCL algorithm. The decoder tree
is broken into partitions that are decoded separately. We show that with
careful selection of list sizes and number of partitions, the proposed
algorithm can outperform conventional SCL while requiring less memory.Comment: 4 pages, 6 figures, to appear at IEEE ICASSP 201
- …